ML110240137
| ML110240137 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 01/17/2011 |
| From: | Repko R Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML110240137 (154) | |
Text
REGIS T. REPKO Duke Vice President r
Energy.
McGuire Nuclear Station Duke Energy MGO1 VP / 12700 Hagers Ferry Rd.
Huntersville, NC 28078 980-875-4111 980-875-4809 fax regis. repko@duke-energy. corn January 17, 2011 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555-0001
SUBJECT:
Duke Energy Carolinas, LLC McGuire Nuclear Station Docket No. 50-369, 370 Lake Norman Maintenance Monitoring Program:
2009 Summary Please find attached a copy of the annual "Lake Norman Maintenance Monitoring Program: 2009 Summary," as required by the National Pollutant Discharge Elimination System (NPDES) permit NC0024392. This report includes detailed results and data comparable to that of previous years. The report was submitted to the North Carolina Department of Environment and Natural Resources on January 11,2011.
Questions regarding the attached report should be directed to Kay L. Crane at (980) 875-4306.
Regis T. Repko www. duke-energy. com
U. S. Nuclear Regulatory Commission January 17, 2011 Page 2 Mr. L. A. Reyes, Regional Administrator U.S. Nuclear Regulatory Commission, Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 Mr. Jon H. Thompson NRC Senior Project Manager U. S. Nuclear Regulatory Commission Mail Stop 8G9A Washington, DC 20555-0001 Joe Brady NRC Senior Resident Inspector McGuire Nuclear Station
LAKE NORMAN MAINTENANCE MONITORING PROGRAM:
2009
SUMMARY
McGuire Nuclear Station: NPDES No. NC0024392 Principal Investigators:
Michael A. Abney John E. Derwort William J. Foris DUKE ENERGY Corporate EHS Services McGuire Environmental Center 13339 Hagers Ferry Road Huntersville, NC 28078 December 2010
LAKE NORMAN MAINTENANCE MONITORING PROGRAM:
2009
SUMMARY
McGuire Nuclear Station: NPDES No. NC0024392 Principal Investigators:
Michael A. Abney John E. Derwort William J. Foris 4
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ACKNOWLEDGMENTS The authors wish to express their gratitude to a number of individuals who made significant contributions to this report. First, we are much indebted to the EHS Scientific Services field staff in carrying out a complex, multiple-discipline sampling effort that provides the foundation of this report. Kim Baker, Dave Coughlan, Bob Doby, Duane Harrell, Glenn Long, and Todd Lynn conducted fisheries collections and sample processing. Jan Williams, Chase Fulk, Bill Foris, Josh Quinn, Chuck Campbell and Glenn Long performed water quality field collections and data analyses. John Williamson assembled the plant operating data. Jan Williams, Glenn Long, and John Derwort conducted plankton sampling, sorting, and taxonomic processing.
We would also like to acknowledge the valuable contributions of Sherry Reid. The benefit of her diligent efforts and patience in assembling and editing several drafts of the report can hardly be overstated.
Finally, we are indebted to multiple reviewers; including Penny Franklin, Duane Harrell, Ron Lewis, and John Velte.
The insightful commentary and suggestions from these individuals and also between co-authors have benefited the report in myriad ways.
ii
TABLE OF CONTENTS EXECUTIVE SUM M A RY...................................................................................................
v LIST OF TABLES............................................................................................................
xi LIST OF FIGURES............................................................................................................
xiii CHAPTER 1-MCGUIRE NUCLEAR STATION............................................................
1-1 IN TRODU CTION...........................................................................................................
1-1 OPERA TION A L DATA FOR 2009...............................................................................
1-1 CH APTER 2-W A TER Q UA LITY.....................................................................................
2-1 INTROD U CTION...........................................................................................................
2-1 M ETHO D S AN D M ATERIALS....................................................................................
2-1 RESULTS AN D D ISCU SSION......................................................................................
2-4 Precipitation and A ir Tem perature...............................................................................
2-4 Tem perature and D issolved Oxygen............................................................................
2-5 Reservoir-W ide Tem perature and D issolved Oxygen.................................................
2-8 Striped Bass H abitat...................................................................................................
2-10 Turbidity and Specific Conductance..........................................................................
2-11 pH and A lkalinity.......................................................................................................
2-12 M ajor Cations and Anions.........................................................................................
2-13 N utrients.....................................................................................................................
2-13 M etals.........................................................................................................................
2-13 FUTURE STUD IES......................................................................................................
2-14 SUM M ARY..................................................................................................................
2-15 CH A PTER 3-PH Y TO PLAN K TO N...................................................................................
3-1 INTROD UCTION...........................................................................................................
3-1 M ETHOD S AN D M ATERIALS....................................................................................
3-1 RESULTS AN D D ISCU SSION......................................................................................
3-2 Standing Crop..............................................................................................................
3-2 Chlorophyll a............................................................................................................
3-2 Total Abundance...........................................
3-4 Seston...........................................................................................................................
3-5 Secchi Depths...............................................................................................................
3-6 Com m unity Com position.............................................................................................
3-6 Species Com position and Seasonal Succession...........................................................
3-6 FUTURE STUD IES........................................................................................................
3-8 SUM M ARY....................................................................................................................
3-8 CH APTER 4-ZO O PLAN K TO N........................................................................................
4-1 INTR OD UCTION...........................................................................................................
4-1 M ETHOD S AND M ATERIALS....................................................................................
4-1 iii
RESULTS AND DISCU SSION......................................................................................
4-2 Total Abundance..........................................................................................................
4-2 Com m unity Com position.............................................................................................
4-4 Copepoda..................................................................................................................
4-5 Cladocera..................................................................................................................
4-5 Rotifera.....................................................................................................................
4-6 FUTURE STUD IES........................................................................................................
4-6 SUM M ARY....................................................................................................................
4-6 CH APTER 5-FISH ERIES..................................................................................................
5-1 INTRODU CTION...........................................................................................................
5-1 M ETHOD S AND M ATERIALS....................................................................................
5-1 Spring Electrofishing Survey.......................................................................................
5-1 Fall ElectrofishingYoung-of-Y ear Bass Survey..........................................................
5-2 Sum m er Striped Bass M ortality Surveys.....................................................................
5-2 Striped Bass N etting Survey.......................................................................................
5-3 Fall Hydroacoustics and Purse Seine Surveys.............................................................
5-3 Fall Crappie Trap-N et Survey......................................................................................
5-3 RESULTS AN D D ISCU SSION......................................................................................
5-4 Spring Electrofishing Survey.......................................................................................
5-4 Fall Electrofishing Young-of-Year Black Bass Survey...............................................
5-6 Sum m er Striped Bass M ortality Surveys.....................................................................
5-6 W inter Striped Bass N etting Survey............................................................................
5-6 Fall Hydroacoustics and Purse Seine Surveys.............................................................
5-6 Fall Crappie Trap-N et Survey......................................................................................
5-7 SUM M ARY..............................................................................................................
5-7 LITERATURE CITED.......................................................................................................
L-1 iv
EXECUTIVE
SUMMARY
In accordance with National Pollutant Discharge Elimination System (NPDES) permit number NC0024392 for McGuire Nuclear Station (MNS), the Lake Norman Maintenance Monitoring Program continued during 2009.
Overall, no obvious long-term impacts of station operations were observed in water quality, phytoplankton, zooplankton, and fish communities. The 2009 station operation data is summarized and continues to demonstrate compliance with thermal limits and cool water requirements.
Annual precipitation in the vicinity of MNS in 2009 totaled 144.3 cm or 25.3 cm more than observed in 2008 (119.0 cm) and 26.7 cm more than the long-term average of 117.6 cm.
Year 2009 annual rainfall was also the second highest measured since 1975, exceeded only in 2003.
Temporal and spatial trends in water temperature and dissolved oxygen (DO) concentration in 2009 were similar to those observed historically, and all data were within the range of previously measured values. Water temperatures in winter 2009 were either equal to or cooler than measured in 2008 and generally paralleled differences exhibited in monthly air temperature data, but with about a one-month lag time.
Summer (June, July, and August) water temperatures in 2009 were generally slightly cooler (maximum = 3.5 °C) than observed in 2008 in both zones, with the most pronounced differences observed in the upper 15 m of the water column. Fall and early winter water temperatures in 2009 were consistently either equal to or warmer in both zones than those measured in 2008, indicating that the reservoir was cooling at a slower rate in 2009 than 2008. This pattern followed the trend exhibited in air temperatures. Temperatures at the discharge location in 2009 were generally similar to 2008 and historical data. The warmest discharge temperature of 2009 (37.1 'C) occurred in September and was 1.4 'C cooler than the 2008 maximum measured in August.
Seasonal and spatial patterns of DO in 2009 were reflective of the patterns exhibited for temperature, i.e., generally similar in both the mixing and background zones. Winter DO values in 2009 were generally equal to or greater than measured in 2008 whereas spring values were either equal to or slightly less than observed in 2008 and were correlated with interannual differences in water temperatures.
Summer DO values in 2009 were highly variable throughout the water column in both the mixing and background zones ranging from highs of 6.0 to 8.0 mg/L in surface waters to lows of 0.0 to 2.0 mg/L in bottom waters. The temporal development of the negative heterograde DO curve in summer 2009 occurred earlier v
and progressed more rapidly than in 2008 and earlier years, and may have been related to increased inputs of allochthonous organic matter associated with above average spring rains.
Considerable differences were observed between 2009 and 2008 late summer and fall DO values in both the mixing and background zone, especially in the metalimnion and hypolimnion. The 2009 fall DO data indicate that convective reaeration of the water column proceeded at a somewhat slower rate than observed in corresponding months in 2008 despite exhibiting similar September profiles. Consequently, 2009 DO levels at most depths were either equal to or less than observed in 2008.
These between-year differences in DO corresponded strongly with the degree of thermal stratification which, in turn, was correlated with interannual differences in air temperatures. The seasonal pattern of DO in 2009 at the discharge location was similar to that measured historically, with the highest values observed during the winter and lowest observed in the summer and early fall.
The lowest DO concentration measured at the discharge location in 2009 (5.2 mg/L) occurred in July and August and was 1.1 mg/L higher than the historical minimum, measured in August 2003 (4.1 mg/L).
Reservoir-wide isotherm and isopleth information for 2009, coupled with heat content and hypolimnetic oxygen data, illustrated that Lake Norman exhibited thermal and oxygen dynamics characteristic of historical conditions and similar to other Southeastern reservoirs of comparable size, depth, flow conditions, and trophic status. Suitable pelagic habitat for adult striped bass, defined as that layer of water with temperatures < 26 °C and DO levels _>
2.0 mg/L, was found lake-wide from mid-September 2008 through mid-July 2009.
Beginning in late June 2009, habitat reduction proceeded rapidly throughout the reservoir both as a result of deepening of the 26 *C isotherm and metalimnetic and hypolimnetic deoxygenation. Habitat reduction was most severe from mid-July through early September.
Observed striped bass mortalities in 2009 totaled 362 fish.
All chemical parameters measured in 2009 were similar to 2008 and within concentration ranges previously reported during both preoperational and operational years of MNS.
Specific conductance values and all cation and anion concentrations were low. Values of pH were within historical ranges in both the mixing and background zones. A comparison of long-term (1999 - 2009) pH data for Lake Norman with a comparable site sampled by North Carolina Department of Environment and Natural Resources (NCDENR) illustrated discrepancies in descriptive statistics and no temporally decreasing trend, in contrast to that observed by the State. It's not clear why this disparity exists.
vi
Nutrient concentrations were low with most values reported close to or below the analytical reporting limit (ARL) for that test. Total phosphorus concentrations were slightly higher than measured in 2008 but within the historical range. Concentrations of metals in 2009 were low and often below the ARL. All values for cadmium and lead were reported as either equal to or below the ARL for that parameter. All zinc values except two were above the ARL of 1.0 pgg/L and all copper concentrations, measured as total recoverable copper, were < 2.5 jtg/L.
All 2009 values for cadmium, lead, zinc, copper and iron were below the State water quality standard or action level for each of these metals. Manganese concentrations were generally low in 2009, except during the summer and fall when bottom waters were anoxic and redox induced releases of manganese occurred. The highest concentration of manganese reported in 2009 (2,130 gtg/L) was measured in November in the bottom waters in the mixing zone.
Lake Norman is classified as oligo-mesotrophic based on long-term, annual mean phytoplankton concentrations. Lake-wide mean chlorophyll a concentrations (average of all samples collected during each season) were generally within historical ranges during 2009, but the lake-wide mean for November was very near the long-term minimum for that time of year. The lake-wide average in February was above the long-term mean, while averages for May and August were below long-term means for these periods. Seasonally, chlorophyll a concentrations decreased from February through May, increased through August to the annual lake-wide maximum and then declined in November to the annual minimum. All values were below the NC State Water Quality standard of 40 Rg/L.
Maximum chlorophyll a concentrations among sampling locations were observed at Location 69.0 (furthest uplake) during February and August, while the May and November maxima were recorded from Location 15.9. The trend of increasing chlorophyll concentrations from downlake to uplake, observed during many previous years, was apparent for the most part during all sampling periods of 2009.
Seston dry and ash-free weights were most often higher in 2009 than in 2008. A general pattern of increasing values from downlake to uplake was observed during May and August 2009, as was observed with chlorophylls and algal standing crops; however, in February and November, this pattern was not apparent. Maximum dry and ash-free weights were generally observed at Location 69.0, while minimum values occurred most often at Locations 2.0 through 9.5.
vii
Secchi depths reflected suspended solids, with shallow depths related to high dry weights.
The lake-wide mean secchi depth was slightly lower in 2009 than in 2008 and within historical ranges observed since data was first recorded in 1992.
Diversity, or the number of phytoplankton taxa in 2009 was the highest recorded since the beginning of the Program in 1987. Ten taxa previously unrecorded during the Lake Norman Maintenance Monitoring Program were identified during 2009.
The taxonomic compositions of phytoplankton communities during 2009 were similar to those of most previous years with the exception that diatoms were dominant in February rather than cryptophytes. Diatoms were dominant during all sampling months except August, when green algae dominated phytoplankton assemblages. Blue-green algae were slightly more abundant during 2009 than during 2008, but typically comprising 2% or less of total densities.
The diatom Tabellariafenestrata was the most important species during May and November at all locations.
The most abundant diatoms in May were Cyclotella stelligera and Fragillaria crotonensis. The small desmid, Cosmarium asphearosporum var. strigosum, was dominant in August 2009. All of these taxa have been common and abundant throughout the Lake Norman Maintenance Monitoring Program.
During 2009, seasonal maximum densities among zooplankton assemblages varied considerably and no consistent seasonal trends were observed. Maxima occurred in winter and fall, while minima most often occurred in the spring. As in past years, epilimnetic densities were higher than whole-column densities. Mean zooplankton densities tended to be higher among background locations than among mixing zone locations during 2009. Spatial trends of zooplankton populations were similar to those of the phytoplankton in winter and spring, with increasing densities from downlake to uplake. During summer and fall, this spatial trend was not observed.
Long-term trends showed much higher year-to-year variability at background locations than at mixing zone locations Epilimnetic zooplankton densities were generally within ranges of those observed in previous years. The exceptions were record high densities uplake in the winter and downlake in the fall.
viii
Since the Lake Norman Maintenance Monitoring Program began in 1987, 123 zooplankton taxa have been observed in samples. Of these, 53 taxa were identified in 2009 as compared to 48 in 2008.
During 2009, rotifers were dominant in most samples collected from Lake Norman.
Conversly, in 2008 microcrustaceans (copepods and cladocerans) showed overall predominance, especially in epilimnetic samples of the Mixing Zone (Locations 5.0 and 8.0) where their relative abundances were the highest yet recorded from 1988 - 2009. During 2009, the relative abundances of microcrustaceans were within historical ranges.
Overall, relative abundance of copepods in 2009 was less than in 2008.
Rotifers were dominant in over 60% of all samples. The relative abundance of microcrustaceans decreased substantially in the mixing zone in 2009 and their percent compositions at these locations were in the low historical range. At background locations, microcrustaceans showed less dramatic decreases during 2009 and percent compositions were within historical ranges of past years. Historically, copepods and rotifers have most often shown annual peaks in the spring, while cladocerans continued to demonstrate year-to-year variability.
Copepods were dominated by immature forms. Adults rarely accounted for more than 7% of zooplankton densities.
As in previous years, the most important adult copepod was Tropocyclops. Epishura was also important in winter and spring. Bosminopsis dominated cladoceran populations during the summer, while Diaphanosoma was an important constituent of spring populations. The most abundant rotifers observed in 2009, as in many previous years, were Polyarthra, Keratella, and Asplanchna. Plygura, Conochilus, and Ploeosoma were also important among rotifer populations.
In accordance with the Lake Norman Maintenance Monitoring Program, monitoring of specific fish population parameters continued during 2009. Spring electrofishing indicated that numbers and biomass of fish in 2009 were generally similar to those noted since 1993.
The fish populations in the three sampling areas were comprised of 16 to 20 species of fish and two hybrid complexes. Fish collections were numerically dominated by centrarchids.
Largemouth bass number of individuals and biomass were the lowest recorded since sampling began in 1993.
Spotted bass number of individuals and biomass continue to increase, possibly displacing largemouth bass. Summer striped bass mortalities were the highest since 2004. The forage fish population estimate was the second highest estimate ix
since surveys began in 1997. Alewife percent composition and modal threadfin shad total length class both increased and were the highest values since 2004.
Lake Norman Maintenance Monitoring Program results from 2009 are consistent with results from previous years. No obvious short-term or long-term impacts were observed in the water quality, phytoplankton, zooplankton, and fish communities of Lake Norman.
McGuire Nuclear Station continues to demonstrate compliance with thermal limits and cool water requirements.
x
LIST OF TABLES Table Title Page 1-1 Average monthly capacity factors (%) and monthly average discharge water tem peratures for M N S during 2009............................................................................
1-2 2-1 Water quality 2009 program for the MNS NPDES Maintenance Monitoring Program on Lake N orm an.........................................................................................
2-18 2-2 Analytical methods and reporting limits employed in the MNS NPDES Maintenance Monitoring Program for Lake Norman................................................
2-19 2-3 Heat content calculations for the thermal regime in Lake Norman for 2008 and 2009....................................................................................................................
2-20 2-4 A comparison of areal hypolimnetic oxygen deficits (AHOD), summer chlorophyll a (Chl a), Secchi depth, and mean depth of Lake Norman and 18 TV A reservoirs.....................................................................................................
2-21 2-5 Quarterly surface (0.3 m) and bottom (bottom minus 1 m) water chemistry for the McGuire Nuclear Station discharge, mixing zone, and background locations on Lake Norman during 2008 and 2009....................................................
2-22 3-1 Mean chlorophyll a concentrations (ptg/L) in composite samples and Secchi depths (in) observed in Lake Norman in 2009..........................................................
3-10 3-2 Mean phytoplankton densities (units/mL) and biovolumes (mm3/m3) by location and sample month from samples collected in Lake Norman during 2 00 9...........................................................................................................................
3-11 3-3 Total mean seston dry and ash free-dry weights (mg/L) from samples collected in Lake Norm an during 2009.....................................................................
3-11 3-4 Phytoplankton taxa identified in quarterly samples collected in Lake Norm an each year from 1994 to 2009.......................................................................
3-12 3-5 Dominant classes, their most abundant species, and their percent composition (in parentheses) at Lake Norman locations during each sam pling period of 2009............................................................................................
3-24 4-1 Total zooplankton densities (No. X 1000/m 3), densities of major zooplankton taxonomic groups, and percent composition (in parentheses) of major taxa in the epilimnion and whole column net tow samples collected from Lake Norman in winter (February), spring (May), summer (August),
and fall (N ovem ber) 2009...........................................................................................
4-9 4-2 Zooplankton taxa identified from samples collected quarterly on Lake N orm an from 1987 - 2009........................................................................................
4-11 4-3 Dominant copepod (adults), cladoceran, and rotifer taxa and their percent composition (in parentheses) of the copepod, cladoceran and rotifer densities by location and sample period in Lake Norman in 2009...........................
4-14 xi
LIST OF TABLES, Continued Table Title Page 5-1 Number of individuals (No.) and biomass (Kg) of fish collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake N orm an, A pril 2009...........................................................................................
5-9 5-2 Mean TL (mm) at age (years) for spotted bass and largemouth bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, M NS) in Lake Norm an, April 2009..........................................................................
5-10 5-3 Comparison of mean TL (mm) at age (years) for largemouth bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, April 2009, to historical largemouth bass mean lengths.......................................................................................................................
5-10 5-4 Striped bass mortalities observed in Lake Norman during weekly July and August surveys. No mortalities were observed Jul 10, 31 or Aug 13, 21, 24.......... 5-11 5-5 Lake Norman forage fish densities (No./ha) and population estimates from Septem ber 2009 hydroacoustic survey......................................................................
5-11 5-6 Number of individuals (No.), percent composition of forage fish, and threadfin shad modal TL class collected from purse seine surveys in Lake Norman during late summer/fall, 1993 -2009.........................................................
5-12 xii
LIST OF FIGURES Figure Title Page 2-1 Water quality sampling locations (numbered) for Lake Norman.
Approximate locations of MSS, and MNS are also shown.......................................
2-25 2-2a Annual precipitation totals in the vicinity of MNS...................................................
2-26 2-2b Monthly precipitation totals in the vicinity of MNS in 2008 and 2009.................... 2-26 2-2c Mean monthly air temperatures recorded at MNS beginning in 1989...................... 2-27 2-3 Monthly mean temperature profiles for the MNS background zone in 2008 and 2009....................................................................................................................
2-28 2-4 Monthly mean temperature profiles for the MNS mixing zone in 2008 and 2009...........................................................................................................................
2-30 2-5 Monthly surface (0.3 m) temperature and dissolved oxygen data at the discharge location (Location 4.0) in 2008 and 2009.................................................
2-32 2-6 Monthly mean dissolved oxygen profiles for the MNS background zone in 2008 and 2009...........................................................................................................
2-33 2-7 Monthly mean dissolved oxygen profiles for the MNS mixing zone in 2008 and 2009....................................................................................................................
2-35 2-8 Monthly reservoir-wide temperature isotherms for Lake Norman in 2009............... 2-37 2-9 Monthly reservoir-wide dissolved oxygen isopleths for Lake Norman in 2009...........................................................................................................................
2-4 0 2-1 Oa Heat content of the entire water column and the hypolimnion in Lake N orm an in 2009........................................................................................................
2-43 2-l0b Dissolved oxygen content and percent saturation of the entire water column and the hypolimnion of Lake Norman in 2009.........................................................
2-43 2-11 Striped bass habitat in Lake Norman in June, July, August, and September 2009...........................................................................................................................
2-44 2-12 Lake Norman lake levels, expressed in meters above mean sea level (mmsl) for 2002, 2003, 2004, 2005, 2006, 2007, 2008, and 2009. Lake level data correspond to the water quality sampling dates over this time period...................... 2-46 2-13 Lake Norman pH values for Locations 62.0 and 69.0 over period 1999 -
2009. Also included are corresponding descriptive statistical data.........................
2-47 3-1 Phytoplankton chlorophyll a, densities, biovolumes, and seston weights at locations in Lake Norman in February, May, August, and November 2009............. 3-25 3-2 Lake Norman phytoplankton chlorophyll a seasonal maximum and minimum lake-wide means since August 1987 compared with the long-term seasonal lake-wide means and lake-wide means for 2009........................................
3-26 3-3 Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman from February 1988 -2009.............................................
3-27 3-4 Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman from May 1988 - 2009...................................................
3-28 xiii
LIST OF FIGURES, Continued Figure Title Page 3-5 Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman during August 1987 - 2009 (Note: axis for 15.9 and 69.0, and that clear data points represent long-term maxima)...........................
3-29 3-6 Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman during November 1987-2009 (Note: change in axis, and that clear data points represent long-term maxima)...................................
3-30 3-7 Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 2.0 in Lake Norman during 2 009...........................................................................................................................
3-3 1 3-8 Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 5.0 in Lake Norman during 2009...........................................................................................................................
3-32 3-9 Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 9.5 in Lake Norman during 2 009...........................................................................................................................
3-34 3-10 Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 11.0 in Lake Norman during 2009...........................................................................................................................
3-34 3-11 Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 15.9 in Lake Norman during 2 009...........................................................................................................................
3-3 5 4-1 Total zooplankton density by location for samples collected in Lake Norman in 2009.......................................................................................................................
4-16 4-2 Zooplankton community composition by sample period and location for epilimnetic samples collected in Lake Norman in 2009...........................................
4-17 4-3 Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the winter periods of 1988 - 2009..............................
4-18 4-4 Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the spring periods of 1988 - 2009..............................
4-19 4-5 Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the summer periods of 1987 - 2009...........................
4-20 4-6 Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the fall periods of 1987 - 2009...................................
4-21 4-7 Annual percent composition of major zooplankton taxonomic groups from mixing zone locations (Locations 2.0 and 5.0 combined) during 1988 -
2009 (Note: Does not include Location 5.0 in the fall of 2002 or winter sam ples from 2005)...................................................................................................
4-22 4-8 Annual percent composition of major zooplankton taxonomic groups from background Locations (Locations 9.5, 11.0, and 15.9 combined) during 1988 -2009 (Note: Does not include winter samples from 2005)...........................
4-23 xiv
LIST OF FIGURES, Continued Figure Title Page 4-9 Copepod densities during each season of each year among epilimnetic samples collected in Lake Norman from 1990 - 2009 (mixing zone = mean of Locations 2.0 and 5.0; background = mean of Locations 9.5, 11.0, and 15.9)..........................................................................................................................
4-24 4-10 Cladoceran densities during each season of each year among epilimnetic samples collected in Lake Norman from 1990 - 2009 (mixing zone = mean of Locations 2.0 and 5.0; background = mean of Locations 9.5, 11.0, and 15.9)..........................................................................................................................
4-2 5 4-11 Rotifer densities during each season of each year among epilimnetic samples collected in Lake Norman from 1990 - 2009 (mixing zone = mean of Locations 2.0 and 5.0; background = mean of Locations 9.5, 11.0, and 15.9)......... 4-26 5-1 Sampling locations and zones associated with fishery assessments in Lake N orm an......................................................................................................................
5-13 5-2 Number of individuals (a) and biomass (b) of fish collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, March/April 1993 - 1997 and 1999 - 2009......................................
5-14 5-3 Number of individuals (a) and biomass (b) of spotted bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norm an, M arch/April 2001 - 2009..................................................................
5-15 5-4 Size distributions of spotted bass (a) and largemouth bass (b) collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake N orm an, A pril 2009.........................................................................................
5-16 5-5 Condition (Wr) for spotted bass (a) and largemouth bass (b) collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake N orm an, A pril 2009.........................................................................................
5-17 5-6 Number of individuals (a) and biomass (b) of largemouth bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, March/April 1993 - 1997 and 1999 - 2009.......................
5-18 5-7 Number of young-of-year black bass (< 150 mm) collected from electrofishing five 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norm an, November 2005 - 2009.................................................................
5-19 5-8 Mean TL and condition (Wr) by age of striped bass collected in Lake Norman, December 2009. Numbers of fish by age are inside bars..........................
5-19 5-9 Zonal and lake-wide population estimates of pelagic forage fish in Lake Norm an, Septem ber 1997 - 2009..............................................................................
5-20 5-10 Number of individuals and size distribution of threadfin shad and alewife collected from purse seine surveys in Lake Norman, September 2009.................... 5-20 xv
CHAPTER 1 MCGUIRE NUCLEAR STATION INTRODUCTION The following annual report was prepared for the McGuire Nuclear Station (MNS) National Pollutant Discharge Elimination System (NPDES) permit (# NC0024392) issued by North Carolina Department of Environment and Natural Resources (NCDENR).
This report summarizes environmental monitoring of Lake Norman conducted during 2009.
OPERATIONAL DATA FOR 2009 Station operational data for 2009 are listed in Table 1-1.
In most months, the average monthly capacity factor was near or slightly above 100% except in September and October when maintenance was performed on Unit 2. The monthly average capacity factors for MNS were 102.4, 100.4 and 57.0% during July, August and September, respectively. These are the months when conservation of cool water is most critical and compliance with discharge temperatures is most challenging. These three months are also when the thermal limit for MNS increases from a monthly average of 95.0 'F (35.0 'C) to 99.0 'F (37.2 °C). The average 2009 monthly discharge temperature was 95.8 'F (35.4 'C) for July, 98.3 'F (36.8 1C) for August and 94.0 'F (34.4 'C) for September. The volume of cool water in Lake Norman was tracked throughout the year to ensure that an adequate volume was available to comply with both the Nuclear Regulatory Commission Technical Specification requirements and the NPDES discharge water temperature limits.
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Table 1-1. Average monthly capacity factors (%) and monthly average discharge water temperatures for MNS during 2009.
MONTHLY AVERAGE MONTHLY AVERAGE NPDES DISCHARGE CAPACITY FACTORS (%)
TEMPERATURES Month Unit 1 Unit 2 Station OF oc January 105.38 105.65 105.51 68.6 20.3 February 104.99 105.60 105.29 67.2 19.6 March 105.17 105.56 105.36 71.8 22.1 April 105.08 105.24 105.16 77.2 25.1 May 104.19 104.64 104.42 83.8 28.8 June 103.12 103.83 103.48 90.7 32.6 July 102.01 102.74 102.38 95.8 35.4 August 101.27 99.54 100.40 98.3 36.8 September 101.77 12.17 56.97 94.0 34.4 October 103.45 66.60 85.02 84.3 29.1 November 104.16 105.27 104.72 80.1 26.7 December 104.71 105.54 105.13 73.4 23.0 Average 103.77 93.53 98.65 82.1 27.8 1-2
CHAPTER 2 WATER QUALITY INTRODUCTION The objectives of the water quality portion of the MNS NPDES Maintenance Monitoring Program (MMP) are to:
- 1. maintain continuity in the water quality data base of Lake Norman to allow detection of any significant station-induced and/or natural change in the physicochemical structure of the lake; and
- 2. compare, where applicable, these physicochemical data to similar data in other hydropower reservoirs and cooling impoundments in the Southeast.
This report focuses primarily on 2008 and 2009 data. Where appropriate, reference to pre-2008 data will be made by citing reports previously submitted to the NCDENR.
METHODS AND MATERIALS The complete water quality monitoring program for 2009, including specific variables, locations, depths, and frequencies is outlined in Table 2-1. Sampling locations are identified in Figure 2-1.
Sampling locations were selected at the initation of the Lake Norman Maintenance Monitoring Program in 1986 to provide a thorough assessment of water quality throughout the spatial expanse of the reservoir and include sites within the projected impact of the thermal discharge from MNS, and in background zones.
Physicochemical data collected at these locations also serve to track the temporal and spatial variability in striped bass habitat in the reservoir during the stratified period.
Measurements of temperature, dissolved oxygen (DO), DO percent saturation, pH, and specific conductance were taken, in situ, at each location with a Hydrolab Data Sonde (Hydrolab 2006) starting at the lake surface (0.3 m) and continuing at one-meter intervals to lake bottom. Pre-and post-calibration procedures associated with operation of the Hydrolab 2-1
were strictly followed, and documented in hard-copy format. Hydrolab data were captured and stored electronically, and following data validation, converted to spreadsheet format.
Water samples for laboratory analysis were collected with a Kemmerer or Van Dorn water bottle at the surface (0.3 in), and from one meter above bottom, where specified (Table 2-1).
Samples not requiring filtration were placed directly in single-use polyethylene terephthalate (PET) bottles which were pre-rinsed in the field with lake water just prior to obtaining a sample.
Samples requiring acidification, but no filtration, were placed directly in pre-acidified high density polyethylene (HDPE) bottles. Samples requiring filtration were first processed in the field by filtering through a 0.45-pm filter (Gelman AquaPrep 600 Series Capsule) which was pre-rinsed with 500 mL of sample water, and then placed in pre-acidified HDPE bottles (Table 2-1). Upon collection, all water samples were immediately stored in the dark, and on ice, to minimize the possibility of physical, chemical, or microbial transformation.
Analytical methods, reporting limits, and sample preservation techniques employed were identical to those used in 2008, except where noted, and are summarized in Table 2-2. All laboratory water quality analyses were performed by the Duke Energy analytical laboratory located in Huntersville, NC. This laboratory is certified to perform analytical assessments for inorganic and organic parameters in North Carolina (North Carolina Division of Water Quality, certificate number 248), South Carolina (South Carolina Department of Health and Environmental Control, certificate number 99005), and New York (New York Department of Health, certificate number 11717).
A comprehensive Quality Assurance/Quality Control Program (QA/QCP) is fundamental to the collection, reporting, and interpretation of water quality data, and most investigators implement some type of QA/QCP to identify, quantify, and document bias and variability in data resulting from the collection, processing, shipping, handling and analysis of samples by field and laboratory personnel. Both the United States Environmental Protection Agency (USEPA 1998a, b) and the United States Geological Survey (USGS 1998, 2002) require that any agency-funded project have an approved quality assurance program, and that this program incorporate both a field and laboratory component. USGS also requires that any agency funded study that includes laboratory assessments must also participate in their Standard Reference Program (SRP). This program was originally developed by USGS in the 1960s and currently involves analysis by participating laboratories of standards (blind unknowns) created by the agency on a biannual schedule (USGS 2002).
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The QA/QCP employed for this study followed the recommendation of the USEPA and USGS, and included both a field and laboratory component. Field blanks, i.e. deionized water placed in sample bottles, were subjected to the same sample collection and handling procedures, including filtration, applied to actual samples. Periodically, samples were also split prior to submittal to the laboratory for analysis with the goal of quantifying intra-sample analytical variability. The laboratory QA/QCP involved a variety of techniques commonly used in analytical chemistry and included reagent blanks, spikes, replicates, and performance samples.
To supplement this program, additional performance samples were run on the major ions and nutrients. Beginning in 2005, standards were purchased from the USGS, through the agency's SRP, and submitted biannually to Duke Energy's laboratory to serve as a "double blind" assessment of analytical performance.
These standards allowed quantification of the uncertainty of the analytical results against known values that were within the same concentration matrix as actual samples. The goal of this effort is to assemble analytical uncertainty data for chemical analytes which can be incorporated into statistical analyses assessing trends in time or space.
Water quality data were subjected to various numerical, graphical, and statistical techniques in an attempt to describe spatial and temporal trends within the Lake, and interrelationships among constituents. Whenever analytical results were reported to be equal to or less than the method reporting limit, these values were set equal to the reporting limit for numerical and statistical assessments.
Data were analyzed using two approaches, both of which were consistent with earlier Duke Power Company, Duke Power, and Duke Energy studies on the Lake (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; and Duke Energy 2006, 2007, 2008, 2009). The first method involved partitioning the reservoir into mixing, background, and discharge zones, consolidating the data into these sub-sets, and making comparisons among zones and years.
In this report, the discharge includes only Location 4.0; the mixing zone, Locations 1.0 and 5.0; the background zone includes Locations 8.0, 11.0, and 15.0 (Figure 2-1). The second approach, applied primarily to the in situ data, emphasized a much broader lake-wide investigation and encompassed the plotting of monthly isotherms and isopleths, and summer striped bass habitat. Several quantitative calculations were also performed on the in situ data; these included the calculation at the reservoir level of the areal hypolimnetic oxygen deficit (AHOD), maximum whole-water column and hypolimnion oxygen content, maximum whole-water column and hypolimnion heat content, mean epilimnion and hypolimnion heating rates over the stratified period, and the Birgean heat budget (maximum - minimum heat content).
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Heat and oxygen content were expressed on an area and volume basis for the entire water column, the epilimnion, and the hypolimnion and were calculated according to Hutchinson (1957), using the following equation:
Lt= A.-
TO.Azo dz fZo where; Lt = reservoir heat (Kcal/cm 2) or oxygen (mg/cm 2) content A0 = surface area of reservoir (cm 2)
TO = mean temperature (°C) or oxygen content (mg/L) of layer z Az = area (cm 2) at depth z dz = depth interval (cm) zo = surface Zm - maximum depth (m)
Precipitation and air temperature data were obtained from a meteorological monitoring site established near MNS in 1975. These data are employed principally by Duke Energy as input variables into meteorological modeling studies to address safety issues associated with potential radiological releases into the atmosphere by MNS (Duke Power 2004b), as required by the Nuclear Regulatory Commission. The data also serve to document localized temporal trends in air temperatures and rainfall patterns. Lake level and hydroelectric flow data were obtained from Duke Energy-Carolinas Fossil/Hydro Generation.
RESULTS AND DISCUSSION Precipitation and Air Temperature Annual precipitation in the vicinity of MNS in 2009 totaled 144.3 cm (Figures 2-2a, b) or 25.3 cm more than observed in 2008 (119.0 cm), and 26.7 cm more than the long-term precipitation average for this area (117.6 cm), based on Charlotte, NC airport data. Year 2009 annual rainfall was also the second highest measured since 1975, exceeded only in 2003.
Monthly rainfall in 2009 was greatest in May with 19.4 cm and the least in January with 5.6 cm. Monthly rainfall totals in 2009 exceeded 10 cm in eight separate months.
Air temperatures near the McGuire Nuclear Station in 2009 were generally similar to the long-term mean for most of the year, based on monthly average data, except in January, July 2-4
and December which were cooler than the long-term mean and June and November which were warmer than the historical mean (Figure 2-2c). Differences between 2008 and 2009 air temperatures were most pronounced in November and December (Figure 2-2c).
Temperature and Dissolved Oxygen Water temperatures measured in 2009 illustrated similar temporal and spatial trends in the background and mixing zones (Figures 2-3 and 2-4), as they did in 2008. This similarity in temperature patterns between zones has been a dominant feature of the thermal regime in Lake Norman since MNS began operations in 1983. When between-zone differences in temperatures are observed, they occur predominately during the cooling period, and can be traced to the influence of the thermal discharge at MNS on mixing zone temperatures.
Additionally, interannual differences in water temperatures in Lake Norman, particularly in surface waters in the background zone, typically parallel differences in air temperatures but with a one-month lag time (Duke Power 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Water temperatures in winter 2009 were either equal to or cooler than measured in 2008, with minor differences observed between zones (Figures 2-3 and 2-4).
These interannual differences in water temperatures generally parallel differences in air temperatures (Figure 2-2c), but because lake sampling is routinely performed in the first week of each month the observed data reflect the cumulative influences of meteorology and hydrology prior to that date. Minimum water temperatures in 2009 were recorded in early February and ranged from 7.3 'C to 10.0 'C in the background zone and from 8.0 *C to 11.5 'C in the mixing zone.
Minimum water temperatures measured in 2009 were within the observed historical range (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Summer (June, July, and August) water temperatures in 2009 were generally slightly cooler (maximum = 3.5 'C) than observed in 2008 in both zones, with the most pronounced differences observed in the upper 15 m of the water column. Fall and early winter water temperatures (October, November, and December) in 2009 were consistently either equal to or warmer in both zones than those measured in 2008, indicating that the reservoir was cooling at a slower rate in 2009 than 2008 (Figures 2-3, 2-4). This pattern followed the trend exhibited in air temperatures (Figures 2-2c).
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Temperatures at the discharge location in 2009 were generally similar to 2008 (Figure 2-5) and historical data (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). The warmest discharge temperature of 2009 (37.1
'C) occurred in September and was 1.4 'C cooler than the 2008 maximum measured in August.
Seasonal and spatial patterns of DO in 2009 were reflective of the patterns exhibited for temperature, i.e., generally similar in both the mixing and background zones (Figures 2-6 and 2-7). As observed with water column temperatures, this similarity in DO patterns between zones has been a dominant feature of the oxygen regime in Lake Norman since MNS began operations in 1983.
Winter DO values in 2009 were generally equal to or greater than measured in 2008 whereas spring values were either equal to or slightly less than observed in 2008 (Figures 2-6 and 2-7). The interannual differences in DO values measured during this period appeared to be related predominantly to the differences in water column temperatures in 2009 versus 2008 and were consistent with observations made during previous years (Duke Energy 2007, 2008, 2009). Cooler temperatures would be expected to exhibit higher oxygen values because of increased oxygen solubility and an enhanced convective mixing regime associated with increased water column instability. Conversely, warmer water would be expected to exhibit a lesser oxygen content because of the direct effect of temperature on oxygen solubility, which is an inverse relationship, and indirectly via a restricted convective mixing regime which would limit water column reaeration.
Summer DO values in 2009 were highly variable throughout the water column in both the mixing and background zones ranging from highs of 6.0 to 8.0 mg/L in surface waters to lows of 0.0 to 2.0 mg/L in bottom waters. This pattern is similar to that measured in 2008 and earlier years (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Water column summer DO values in 2009 were generally either equal to or lower than observed in 2008 and were well within historical ranges.
One distinct difference observed between the 2009 and 2008 early summer DO profiles was in the temporal and spatial trends of oxygen concentrations within the water column. Both 2-6
zones exhibited these trends but the differences were most pronounced in the mixing zone.
In 2009 DO levels from the lake surface to 7 m were fairly evenly distributed with depth with concentrations ranging from 6.5 to 7.0 mg/L. Beginning at 7 m, a depth corresponding closely to the thermocline, DO concentrations exhibited a sharp and rapid decline with depth culminating in a minimum concentration of 1.0 mg/L at 10 m. This vertical drop in oxygen equated to a 2.0-mg/L decline in oxygen for every 1 m increase in depth. The 1.0-mg/L concentration extended to a depth of about 20 m and then increased to 2.5 to 3.5 mg/L from 21 m to the lake bottom. The corresponding 2008 DO profile was generally similar except that DO concentrations in the 7 to 20 m depth were considerably higher than observed in 2009.
A vertical oxygen profile with a pronounced middle water layer (metalimnion) of low DO positioned between upper (epilimnion) and lower (hypolimnion) zones of higher oxygen content is described as a negative heterograde oxygen curve (Goldman and Home 1994).
Negative heterograde oxygen curves are commonly observed in Southeastern reservoirs and often caused by vertical differences in animal and microbial respiratory activites associated with the consumption and degradation of both autochthonous and allochthonous derived organic materials (Cole and Hannan 1985). In rare instances, the presence of these types of oxygen curves have been traced to interflows of low DO waters entering the waterbody, most frequently from an upstream reservoir (Cole and Hannan 1985).
The development and progression of the metalimnetic oxygen minimum in summer 2009 occurred earlier and progressed more rapidly than in 2008 and other years. No confirmatory evidence is available, but it's likely that the timing and magnitude of the metalimntic oxygen minimum in 2009 was related to higher than normal inputs of allochthonous organic matter associated with above average spring rains. The 2009 precipitation total for the period March
- June was 51% greater than the long-term average. Ford (1987) found that nutrient and organic loading to DeGray Resevoir in Arkansas was dominated by rainfall and associated terrestrial runoff events during the spring.
Considerable differences were observed between 2009 and 2008 late summer and fall DO values in both the mixing and background zones, especially in the metalimnion and hypolimnion, during the months of October, November and December (Figures 2-6 and 2-7).
These interannual differences in DO levels during the cooling season are common in Catawba River reservoirs and are explained by the effects of variable weather patterns on water column cooling (heat loss) rates and mixing. Cooler air temperatures increase the rate 2-7
and magnitude of water column heat loss, thereby promoting convective mixing and resulting in higher DO values earlier in the year (Figure 2-2c). Conversely, warmer air temperatures delay water column cooling which, in turn, delays the onset of convective mixing of the water column and the resultant reaeration of the metalimnion and hypolimnion.
The 2009 fall DO data indicate that convective reaeration of the water column proceeded at a somewhat slower rate than observed in corresponding months in 2008 despite exhibiting similar September profiles (Figures 2-6 and 2-7). Consequently, 2009 DO levels at most depths were either equal to or less than observed in 2008. These between-year differences in DO corresponded strongly with the degree of thermal stratification which, as discussed earlier, correlated with interannual differences in air temperatures (Figures 2-2c, 2-3, and 2-4). Interannual differences in DO patterns are common not only within the Catawba River Basin, but throughout Southeastern reservoirs and can reflect yearly differences in hydrologic, meteorologic, and limnologic forcing variables (Cole and Hannan 1985; Petts, 1984).
The seasonal pattern of DO in 2009 at the discharge location was similar to that measured historically, with the highest values observed during the winter and lowest observed in the summer and early fall (Figure 2-5). The lowest DO concentration measured at the discharge location in 2009 (5.2 mg/L) occurred in July and August and was 1.1 mg/L higher than the historical minimum, measured in August 2003 (4.1 mg/L).
Reservoir-Wide Temperature and Dissolved Oxygen The monthly reservoir-wide temperature and DO data for 2009 are presented in Figures 2-8 and 2-9. These data are similar to those observed in previous years and are characteristic of cooling impoundments and hydropower reservoirs in the Southeast (Cole and Hannan 1985; Hannan et al. 1979; Petts 1984). Detailed discussions on the seasonal and spatial dynamics of temperature and DO during both the cooling and heating periods in Lake Norman have been presented previously (Duke Power Company 1992, 1993, 1994, 1995, 1996).
The seasonal heat content of both the entire water column and the hypolimnion for Lake Norman in 2009 are presented in Figure 2-10a; additional information on the thermal regime in the reservoir for the years 2008 and 2009 are presented in Table 2-3. Annual minimum heat content for the entire water column in 2009 (8.86 Kcal/cm 2; 8.84 'C) occurred in early February, whereas the maximum heat content (28.51 Kcal/cm2; 28.08 °C) occurred in 2-8
August. Heat content of the hypolimnion exhibited a somewhat different temporal trend as that observed for the entire water column. Annual minimum hypolimnetic heat content also occurred in early February and measured 4.94 Kcal/cm 2 (7.72 °C), but the maximum occurred in late September and measured 15.77 Kcal/cm2 (24.17 'C).
Heating of both the entire water column and the hypolimnion occurred at approximately a linear rate from minimum to maximum heat content. The mean heating rate of the eplimnion equaled 0.10
°C/day and 0.08 °C/day for the hypolimnion and were either equal to or slightly less than observed in 2008 (Table 2-3). The 2009 heat content and heating rate data for Lake Norman were generally similar to that observed in previous years (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
The seasonal oxygen content and percent saturation of the whole water column, and the hypolimnion, are depicted for 2009 in Figure 2-10b. Additional oxygen data can be found in Table 2-4 which presents the 2009 AHOD for Lake Norman and similar earlier estimates for 18 Tennessee Valley Authority (TVA) reservoirs. Reservoir oxygen content was greatest in mid-winter when DO content measured 10.5 mg/L for the whole water column and 10.4 mg/L for the hypolimnion. Percent oxygen saturation values at this time approached 92% for the entire water column and 89% for the hypolimnion, indicating that reaeration of the reservoir did not achieve 100% saturation in 2009. Beginning in early spring, oxygen content began to decline precipitously in both the whole water column and the hypolimnion, and continued to decline linearly until reaching a minimum in late summer.
The minimum summer volume-weighted DO value for the entire water column measured 4.5 mg/L (60%
saturation), whereas the minimum for the hypolimnion was 0.3 mg/L (3.0 % saturation). The mean rate of DO decline in the hypolimnion over the stratified period, i.e., the AHOD, was 0.046 mg/cm2/day (0.071 mg/L/day) (Figure 2-10b), and is similar to that measured in 2008 (Duke Energy 2009).
Hutchinson (1938, 1957) proposed that the decrease of DO in the hypolimnion of a waterbody should be related to the productivity of the trophogenic zone. Mortimer (1941) adopted a similar perspective and proposed the following criteria for AHODs associated with various trophic states; oligotrophic
_< 0.025 mg/cm 2/day, mesotrophic 0.026 mg/cm 2/day to 0.054 mg/cm2/day, and eutrophic __ 0.055 mg/cm 2/day.
Employing these limits, Lake Norman should be classified as mesotrophic based on the calculated AHOD value of 0.046 mg/cm2/day for 2009. The oxygen-based mesotrophic classification agrees well with the mesotrophic classification based on chlorophyll a levels (Chapter 3). The 2009 AHOD value 2-9
is also similar to that found in other Southeastern reservoirs of comparable depth, chlorophyll a status, and Secchi depth (Table 2-4).
Striped Bass Habitat Suitable pelagic habitat for adult striped bass, defined as that layer of water with temperatures
> 26 'C and DO levels _> 2.0 mg/L, was found lake-wide from mid-September 2008 through mid-July 2009. Beginning in late June 2009, habitat reduction proceeded rapidly throughout the reservoir both as a result of deepening of the 26-°C isotherm and metalimnetic and hypolimnetic deoxygenation (Figure 2-11). Habitat reduction was most severe from mid-July through early September when no suitable habitat was observed in the reservoir except in the upper reaches of the reservoir. These conditions were similar to those observed in most previous years.
Historically, a small, but spatially variable zone of habitat is typically observed near and upstream of the confluence of Lyles Creek with Lake Norman. Historical data have illustrated that the presence of suitable habitat in the upper reaches of the reservoir is strongly influenced by both inflows from Lyles Creek and discharges from Lookout Shoals Hydroelectric facility, which generally are somewhat cooler than ambient conditions in Lake Norman. Upon entering Lake Norman, these cooler waters mix with ambient waters and create local refugia.
A refuge was observed in the metalimnion and hypolimnion near the Cowans Ford Dam during this period, but this lasted only until 20 July when DO was reduced to < 2.0 mg/L by microbial demands, thereby eliminating suitable habitat in the lower portion of the reservoir.
Summer habitat conditions for adult striped bass in 2009 were similar to 2008; both these years also exhibited habitat conditions that were more severe than 2004 when the largest striped bass die-off ever was observed in the reservoir (2,610 fish). Conditions in 2009 were most recently similar to those measured in 2007 and 2008 when habitat elimination was observed for a period of about 50 - 60 days. Observed striped bass mortalities in 2009 totaled 362 fish. Additional discussion on the 2009 striped bass mortalities can be found in Chapter 5.
Physicochemical habitat expanded appreciably by mid-September, primarily as a result of epilimnion cooling and deepening, and in response to changing meteorological conditions (Figure 2-2c). The temporal and spatial patterns of striped bass habitat expansion and reduction observed in 2009 were similar to those previously reported in Lake Norman, and many other Southeastern reservoirs (Coutant 1985; Matthews et al. 1985; Duke Power 2-10
Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Turbidity and Specific Conductance Surface turbidity values were generally low at the MNS discharge, mixing zone, and background locations during 2009, ranging from 0.9 to 2.9 NTUs (Table 2-5). Bottom turbidity values were also low over the 2009 study period, ranging from 0.7 to 5.3 NTUs.
Turbidity values observed in 2009 were near the low end of the historical range (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Specific conductance in Lake Norman in 2009 ranged from 65.6 to 105.0 pmhos/cm and was generally similar to that observed in 2008 (Table 2-5), and historically (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Specific conductance values in surface and bottom waters in 2009 were similar throughout the year except during the period of intense thermal stratification (i.e., August and November) when an increase in bottom conductance values was observed at locations within the mixing and background zones. These increases in bottom conductance values appeared to be related primarily to the release of soluble iron and manganese from the lake bottom under anoxic conditions (Table 2-5).
This phenomenon is common in both natural lakes and reservoirs that exhibit extensive hypolimnetic oxygen depletion (Hutchinson 1957, Wetzel 1975) and is an annually recurring phenomenon in Lake Norman.
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pH and Alkalinity During 2009, pH and alkalinity values were similar among MNS discharge, mixing and background zones (Table 2-5). Values of pH were also generally similar to values measured in 2008 (Table 2-5) and historically (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). Values of pH in 2009 ranged from 7.0 to 7.7 in surface waters and from 6.3 to 7.2 in bottom waters. Alkalinity values in 2009 ranged from 14.0 to 16.0 mg/L, expressed as CaCO3, in surface waters and from 14.0 to 22.0 mg/L in bottom waters.
The 2010 Catawba River Basinwide Summary (NCDENR 2010) concluded that pH values throughtout the basin exhibited a significant decline over the period 1997 -
- 2008, beginnining in 2003. Median pH values within the basin ranged from a high of 7.4 in 2001 to a low of 6.5 in 2008. Acid deposition impacts were implicated as a probable explanation.
Included in this database was a site (C3420000) in the upper, riverine reaches of Lake Norman (Figure 1). A plot of surface (0.3 m) pH values in Lake Norman from 1999 - 2009 for Locations 62.0 and 69.0, sites near C3420000 that were measured in conjuction with the MMP for MNS, was constructed for comparison with the State's database (Figure 2-13).
These data (N = 462) illustrated pronounced seasonal variability in pH with values ranging from 6.5 to 7 in the winter and from 8 to 9.3 in mid-summer when algal photosynthesis removed CO2 from solution thereby increasing pH. A slightly increasing temporal trend of pH over this 11-year period was also observed, in contrast to that reported by the State.
Descriptive statistical pH information was reported for site C3420000 for the 2003 through 2007 period and included calculations of maximum, minium and median (NCDENR 2008).
Similar calculations were made on the 2003 - 2007 Duke Energy data set for locations 62.0 and 69.0, as well as for the period 1999 - 2009, and compared to the State's data (Figure 2-13). Maximum, minimum and median statistics for the Duke Energy 2003 through 2007 data ranged from 0.7 to 1.4 pH units higher than comparable State data. Differences between statistical metrics generated from the two Duke Energy pH datasets were minimal (Figure 2-13).
It's unclear why a discrepancy exists between the Duke Energy and NCDENR databases, but a similar disparity was noted for comparable pH data collected by Duke Energy and NCDENR at sites located in lakes Mtn. Island and Wylie (Duke Energy, unpublished data).
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Major Cations and Anions The concentrations of major ionic species in the MNS discharge, mixing and background zones are provided in Table 2-5.
Lake-wide, the major cations were sodium, calcium, magnesium and potassium, whereas the major anions were bicarbonate, sulfate, and chloride.
The overall ionic composition of Lake Norman during 2009 was generally similar to that reported for 2008 (Table 2-5) and previously (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Nutrients Nutrient concentrations in the discharge, mixing and background zones of Lake Norman in 2009 (Table 2-5) were low and generally similar to those measured in 2008 and historically (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). For total phosphorus (TP), all 44 samples analyzed in 2009 except one exceeded 5 gg/L, the analytical reporting limit (ARL), and values were consistently greater than observed in 2008, but within the historical range. The maximum 2009 TP value (27 ptg/L) was observed in a bottom sample at Location 11.0.
All measurements of orthophosphorus (N = 44) in 2009 were recorded as _< 5 pig/L. Nitrite-nitrate and ammonia nitrogen concentrations were low at all locations (Table 2-5) and similar to historical values (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). Overall, nutrients in 2009 were somewhat higher uplake than downlake, but the differences were slight and not statistically significant (p < 0.05). Spatial variability in various chemical constituents, especially nutrient concentrations, is common in long, deep reservoirs (Soballe et al. 1992).
Metals Metal concentrations in the discharge, mixing, and background zones of Lake Norman for 2009 were similar to those measured in 2008 (Table 2-5) and historically (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). Iron concentrations in surface and bottom waters were generally low (_< 0.2 mg/L) 2-13
during 2009 with only 9 of 44 samples exceeding 0.20 mg/L.
The maximum iron concentration measured in 2009 was 0.614 mg/L in the bottom sample taken at Location 1.0 in November. No sample collected in 2009 exceeded the North Carolina water quality action level for iron (1.0 mg/L; NCDENR 2004).
Similarly, 2009 manganese concentrations in the surface and bottom waters were low (< 100 pgg/L), except during the summer and fall when bottom waters were anoxic (Table 2-5).
Manganese concentrations in the bottom waters rose above the State water quality action (200 gig/L; NCDENR 2004) at various locations throughout the lake in summer and fall, and were characteristic of historical conditions (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). The highest concentration of manganese reported in 2009 (2,130 gtg/L) was measured in the bottom waters at Location 1.0; this same sample also recorded the maximum iron concentration for 2009. This phenomenon, i.e., the release of manganese (and iron) from bottom sediments in response to low redox conditions (low oxygen levels), is common in stratified waterbodies (Stumm and Morgan 1970, Wetzel 1975).
Concentrations of other metals in 2009 were low, and often below the ARL for the specific constituent (Table 2-5). These findings are consistent with those reported for earlier years (Duke Power Company 1985, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996; Duke Power 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009). All values for cadmium and lead were reported as either equal to or below the ARL for those parameters. All zinc values except two were above the ARL of 1.0 jtg/L; the maximum 2009 zinc concentration of 10.8 gtg/L was measured in the August surface sample at Location 1.0. All copper concentrations, measured as total recoverable copper, were < 2.5 pgg/L and about 20% (9 of 44) of the values were listed as less than or equal to the ARL of 1.0 gg/L. All values reported for cadmium, lead, zinc, and copper in 2009 were below the State action level for each of these metals (NCDENR 2004).
FUTURE STUDIES No changes are planned for the water chemistry portion of the Lake Norman Maintenance-Monitoring Program.
2-14
SUMMARY
Annual precipitation in the vicinity of MNS in 2009 totaled 144.3 cm or 25.3 cm more than observed in 2008 (119.0 cm), and 26.7 cm more than the long-term of 117.6 cm. Year 2009 annual rainfall was also the second highest measured since 1975, exceeded only in 2003.
Temporal and spatial trends in water temperature and DO in 2009 were similar to those observed historically, and all data were within the range of previously measured values.
Water temperatures in winter 2009 were either equal to or cooler than measured in 2008 and generally paralleled differences exhibited in monthly air temperature data, but with about a one month lag time.
Summer (June, July, and August) water temperatures in 2009 were generally slightly cooler (maximum = 3.5 'C) than observed in 2008 in both zones, with the most pronounced differences observed in the upper 15 m of the water column. Fall and early winter water temperatures in 2009 were consistently either equal to or warmer in both zones than those measured in 2008, indicating that the reservoir was cooling at a slower rate in 2009 than 2008. This pattern followed the trend exhibited in air temperatures. Temperatures at the discharge location in 2009 were generally similar to 2008 and historical data. The warmest discharge temperature of 2009 (37.1 "C) occurred in September and was 1.4 'C cooler than the 2008 maximum measured in August.
Seasonal and spatial patterns of DO in 2009 were reflective of the patterns exhibited for temperature (i.e., generally similar in both the mixing and background zones). Winter DO values in 2009 were generally equal to or greater than measured in 2008 whereas spring values were either equal to or slightly less than observed in 2008 and were correlated with interannual differences in water temperatures.
Summer DO values in 2009 were highly variable throughout the water column in both the mixing and background zones ranging from highs of 6.0 to 8.0 mg/L in surface waters to lows of 0.0 to 2.0 mg/L in bottom waters. The temporal development of the negative heterograde DO curve in summer 2009 occurred earlier and progressed more rapidly than in 2008 and earlier years, and may have been related to higher than normal inputs of allochthonous organic matter associated with above average spring rains.
Considerable differences were observed between 2009 and 2008 late summer and fall DO values in both the mixing and background zone, especially in the metalimnion and hypolimnion. The 2009 fall DO data indicate that convective reaeration of the water column 2-15
proceeded at a somewhat slower rate than observed in corresponding months in 2008 despite exhibiting similar September profiles. Consequently, 2009 DO levels at most depths were either equal to or less than observed in 2008.
These between-year differences in DO corresponded strongly with the degree of thermal stratification which, in turn, was correlated with interannual differences in air temperatures. The seasonal pattern of DO in 2009 at the discharge location was similar to that measured historically, with the highest values observed during the winter and lowest observed in the summer and early fall.
The lowest DO concentration measured at the discharge location in 2009 (5.2 mg/L) occurred in July and August and was 1.1 mg/L higher than the historical minimum, measured in August 2003 (4.1 rng/L).
Reservoir-wide isotherm and isopleth information for 2009, coupled with heat content and hypolimnetic oxygen data, illustrated that Lake Norman exhibited thermal and oxygen dynamics characteristic of historical conditions and similar to other Southeastern reservoirs of comparable size, depth, flow conditions, and trophic status. Suitable pelagic habitat for adult striped bass, defined as that layer of water with temperatures < 26 'C and DO levels >
2.0 mg/L, was found lake-wide from mid September 2008 through mid-July 2009. Beginning in late June 2009, habitat reduction proceeded rapidly throughout the reservoir both as a result of deepening of the 26-°C isotherm and metalimnetic and hypolimnetic deoxygenation.
Habitat reduction was most severe from mid-July through early September. Observed striped bass mortalities in 2009 totaled 362 fish.
All chemical parameters measured in 2009 were similar to 2008 and within the concentration ranges previously reported during both preoperational and operational years of MNS.
Specific conductance values, and all cation and anion concentrations, were low. Values of pH were within historical ranges in both the mixing and background zones. A comparison of long-term (1999 - 2009) pH data for Lake Norman with a comparable site sampled by NCDENR illustrated discrepancies in descriptive statistics and no temporally decreasing trend, in contrast to that observed by the State. It's unclear why this disparity exists.
Nutrient concentrations were low with most values reported close to or below the (ARL) for that test. Total phosphorus concentrations were slightly higher than measured in 2008 but within the historical range. Concentrations of metals in 2009 were low and often below the respective ARLs. All values for cadmium and lead were reported as either equal to or below the ARL for each parameter. All zinc values except two were above the ARL of 1.0 gg/L and all copper concentrations, measured as total recoverable copper, were < 2.5 gg/L. All 2009 2-16
values for cadmium, lead, zinc, copper and iron were below the State water quality standard or action level for each of these metals. Manganese concentrations were generally low in 2009, except during the summer and fall when bottom waters were anoxic and redox induced releases of manganese occurred. The highest concentration of manganese reported in 2009 (2,130 gtg/L) was measured in November in the bottom waters in the mixing zone.
2-17
0 Table 2-1. Water quality 2009 program for the MNS NPDES Maintenance Monitoring Program on Lake Norman.
2009 McGUIRE NPDES SAMPLING PROGRAM 2.0 4.0 5.0 8.0 9.5 11.0 13.0 14.0 15.0 15.9 62.0 69.0 72.0 80.0 PARAMETERS LOCATION 1.0 DEPTH (in) 33 33 5
20 32 23 27 21 10 23 23 15 7
5 4
IN-SITU ANALYSIS Temperature
- Dissolved Oxygen In-situ measurements are collected monthly at the above locations at Im intervals from 0.3m to Im above bottom.
pH Measurements are taken -cvekly from July-August for striped bass habitat. All measurements are taken xvith a Hydrolab Datasonde.
Conductivity NUTRIENT ANALYSES Ammonia Q/T,B Q/T,B Q/T Q/T,B Q/TB Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Nitrate+Nitrite Q/TB Q/T,B Q/T Q/T,B Q/T,B Q/TB Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Orthophosphate Q/TB Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Total Phosphorus Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Silica Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/T,B Chloride Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B TKN Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T.B Q/TB Q/T Q/T,B Q/T,B Q/T,B Total Organic Carbon Q/T,B Q/T,B Q/T Q/T,B, Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/TB Q/T,B Dissolved organic carbon Q/T,B Q/T,B Q/T Q/TB Q/TB Q/T,B Q/T,B QITB Q/T Q/T,B Q/T,B Q/T,B ELEMENTAL ANALYSES Aluminum Q/T,B S/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T QIT,B Q/TB Q/T,B Calcium Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/TB Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Iron Q/TB Q/T,B Q/T Q/T,B Q/T,B Q/TB. Q/TB Q/T,B Q/T Q/TB Q/T,B Q/T,B Magnesium Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/TB Q/TB Q/T,B Q/T Q/T,B Q/T,B Q/T,B Manganese Q/T,B Q/TB Q/T Q/T,B Q/TB Q/TB Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/TB Potassium Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/T,B Q/TB Q/T,B Q/T Q/T,B Q/T,B Q/T,B Sodium Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/TB Q/TB Q/TB Q/T Q/T,B Q/T,B Q/T,B Zinc Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/T,B Q/TB Q/TB Q/T Q/T,B Q/T,B Q/T,B Arsenic Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/TB Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Cadminum Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Copper (TR)'
Q/T,B Q/T,B Q/T Q/T,B Q/T,B QIT,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Copper (Dissolved)
Q/TB Q/T,B Q/T Q/T,B Q/TB Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Lead Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/TB Selenium Q/T,B Q/T,B Q/T Q/TB Q/TB Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B ADDITIONAL ANALYSES Hardness Q/T,B Q/TB Q/T Q/TB Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Alkalinity Q/T,B Q/T,B Q/T Q/T,B Q/T.B Q/T,B Q/T,B Q/TB Q/T Q/T,B Q/T,B Q/T,B Turbidity Q/T,B Q/TB Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Sulfate Q/T,B Q/T,B Q/T Q/T,B Q/TB Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Total Solids Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Q/T,B Q/T,B Q/T Q/T,B Q/T,B Q/T,B Total Suspended Solids Q/T,B Q/T,B Q/T Q/TB Q/T,B Q/T,B Q/T,B QIT,B Q/T Q/T,B Q/T,B Q/T,B 00
- 1. TR= Total Recoverable CODES:
Frequency Q = Quarterly (Feb, May, Aug, Nov)
T = Top (0.3m)
B = Bottom (I m above bottom)
Table 2-2. Analytical methods and reporting limits employed in the 2009 MNS NPDES Maintenance Monitoring Program for Lake Norman.
Parameter Method (EPA/APHA)
Preservation Reporting Limit Alkalinity, Total Total Inflection Point, EPA 310.1 4 C 0.01 meglL Aluminum ICP, EPA 200.7 0.5% HN0 3 0.05 mg/L Cadmium, Total Recoverable ICP Mass Spectroscopy, EPA 200.8 0.5% HNO 3 1.0 pg/La Calcium ICP, EPA 200.7 0.5% HNO 3 30 pig/L Chloride Colorimetric, EPA 325.2 4 *C 1.0 mg/L Copper, Total Recoverable ICP Mass Spectroscopy, EPA 200.8 0.5% HNO 3 1.0 pg/L Copper, Dissolved ICP Mass Spectroscopy, EPA 200.8 0.5% HNO 3 1.0 Iag/L Iron, Total Recoverable ICP, EPA 200.7 0.5% HN0 3 10 pg/L Lead, Total Recoverable ICP Mass Spectroscopy, EPA 200.8 0.5% HNO 3 1.0 pg/L Magnesium Atomic Emission/ICP, EPA 200.7 0.5% HNO 3 30 pg/L Manganese, Total Recoverable ICP Mass Spectroscopy, EPA 200.8 0.5% HNO 3 1.0 pg/L Nitrogen, Ammonia Colorimetric, EPA 350.1 0.5% H2SO 4 20 pg/L Nitrogen, Nitrite + Nitrate Colorimetric, EPA 353.2 0.5% H2SO4 20 pg/L Nitrogen, Total Kjeldahl Colorimetric, EPA 351.2 0.5% H2SO 4 100 pg/L Phosphorus, Orthophosphorus Colorimetric, EPA 365.1 4 °C 5 pg/L Phosphorus, Total Colorimetric, EPA 365.1 0.5% H2SO4 5 pg/L Potassium ICP, EPA 200.7 0.5% HNO 3 250 pg/L Silica APHA 4500Si-F 0.5% HNO 3 500 pg/L Sodium Atomic Emission/ICP, EPA 200.7 0.5% HNO 3 1.5 mg/L Solids, Total Gravimetric, SM 2540B 4 °C 0.1 mg/L Solids, Total Suspended Gravimetric, SM 2540D 4 °C 0.1 mg/L Sulfate Ion Chromatography 4 "C 0.1 mg/L Turbidity Turbidimetric, EPA 180.1 0.5% H2SO4 0.05 NTU Zinc, Total Recoverable ICP Mass Spectroscopy, EPA 200.8 0.5% HNO 3 1.0 pg/L
References:
USEPA 1983, and APHA 1995 V
a Except in May when Reporting Limit equals 0.5 jig/L.
Table 2-3. Heat content calculations for the thermal regime in Lake Norman for 2008 and 2009.
2009 2008 Maximum Areal Heat Content (Kcal/cm2) 28.509 29.062 Minimum Areal Heat Content (Kcal/cm 2) 8.859 9.648 Birgean Heat Budget (Kcal/cm 2) 19.650 19.414 Epilimnion (above 11.5 m) Heating Rate (°C/day) 0.10 0.11 Hypolimnion (below 11.5 m) Heating Rate (0C/day) 0.08 0.08 2-20
Table 2-4.
A comparison of areal hypolimnetic oxygen deficits (AHOD), summer chlorophyll a (Chl a), Secchi depth, and mean depth of Lake Norman and 18 TVA reservoirs.
Reservoir AHOD (mg/cm 2/day)
Summer Chl a Secchi Depth (ptg/L)
(m)
Mean Depth (m)
Lake Norman TVAb Mainstem Kentucky Pickwick Wilson Wheelee Guntersville Nickajack Chickamauga Watts Bar Fort London Tributary Chatuge Cherokee Douglas Fontana Hiwassee Norris South Holston Tims Ford Watauga 0.046 0.012 0.010 0.028 0.012 0.007 0.016 0.008 0.012 0.023 0.041 0.078 0.046 0.113 0.061 0.058 0.070 0.059 0.066 5.1 9.1 3.9 5.9 4.4 4.8 2.8 3.0 6.2 5.9 5.5 10.9 6.3 4.1 5.0 2.1 6.5 6.1 2.9 1.7 1.0 0.9 1.4 1.1 1.1 1.1 1.0 0.9 2.7 1.7 1.6 2.6 2.4 3.9 2.6 2.4 2.7 10.3 5.0 6.5 12.3 5.3 5.3 6.8 5.0 7.3 7.3 9.5 13.9 10.7 37.8 20.2 16.3 23.4 14.9 24.5 b Data from Higgins et al. (1980), and Higgins and Kim (1981).
2-21
Table 2-5. Quarterly surface (0.3 m) and bottom (bottom minus 1 m) water chemistry for the MNS discharge, mixing zone, and background locations on Lake Norman during 2008 and 2009. Values less than detection were assumed to be equal to the detection limit for calculating a mean.
Mixing Zone 1.0 Mixing Zone
2.0 LOCATION
DU:'I-MNS Orucharge 4.0 Surface Mixing Zone
5.0 Background
8.0 Surface Bottom
Background
11.0 Surface Bottom Surface Bottom Surface Bottom Surface Bottom Turbidty (NTU)
Feb 1.9 2.0 1.8 1.6 2.6 1.2 3.9 1.5 2.8 1.1 2.3 1.4 3.8 1.2 2.1 1.5 5.3 1.7 2.9 1.5 4.3 1.4 May 1.6 1.3 2.3 1.7 1.9 1.3 3.1 1.2 1.8 1.3 1.8 1.3 2.5 2.1 1.1 1.4 2.3 1.4 1.1 1.6 3.0 4.1 Aug 1.0 1.9 0.7 1.1 1.9 3.3 0.7 1.0 0.9 2.1 1.0 1.7 4.1 29 1.1 1.5 1.2 1.4 1.4 2.0 1.0 1.7 Nov 1.8 2.1 2.7 2.0 1.6 1.9 2.4 1.6 2.0 1.1 1.7 1.1 2.9 2.6 1.9 1.7 3.9 3.7 2.4 2.9 4.5 3.9 Annual Mean 1.6 1.8 1.9 1.6 2.0 1.9 2.5 1.3 1.9 1.4 1.7 1.4 3.3 2.2 1.6 1.5 3.2 2.1 2.0 2.0 3.2 2.8 Specific Conductance (umhu/cm)
Feb 72.0 66.0 72.1 65.6 72.7 66.1 72.5 68.1 73.6 67.3 73.4 66.3 72.2 65.6 72.5 65.8 71.8 65.1 71.1 76.4 64.9 72.7 May 71.4 72.4 71.4 71.1 71.7 72.5 71.2 70.9 71.8 73.6 72.5 72.8 71.1 71.5 72.6 72.4 70.8 72.6 71.9 77.7 70.2 76.4 Aug 65.6 76.1 73.6 75.6 66.1 75.0 72.1 75.9 65.9 75.3 65.6 75.6 77.0 796.
65.9 75.3 72.7 74.4 67.4 80.6 73.9 75.0 Nov 69.0 76.8 105.0 78.2 69.0 76.9 88.0 77.6 70.0 77.3 69.0 77.0 69.0 76.6 69.0 76.9 71.0 77.3 69.0 78.4 69.0 76.6 Annual Mean 69.5 72.8 80.5 72.6 69.9 72.6 76.0 73.1 70.3 73.4 70.1 72.9 72.3 73.3 70.0 72.6 71.6 72.4 69.9 78.3 69.5 75.2 pH (unite)
Feb 7.0 7.2 6.9 7.1 7.3 7.4 7.1 7.2 7.3 7.3 7.4 7.4 7.1 7.2 7.5 7.3 7.2 7.2 7.3 7.3 7.0 7.2 May 7.0 7.4 6.6 6.9 7.2 7.5 6.6 6.9 7.1 7.4 7.5 7.5 6.7 6.9 7.6 7.6 6.7 6.9 7.7 7.6 6.6 6.8 Aug 7.1 7.6 6.3 6.2 7.1 7.4 6.3 6.3 7.0 7.1 7.1 7.4 6.5 6.4 7.4 8.0 6.3 6.3 7.4 8.4 6.3 6.3 Nov 7.3 7.5 7.0 7.2 7.3 7.6 6.8 7.2 7.4 7.6 7.4 7.6 7.0 7.2 7.3 7.5 7.0 7.2 7.3 7.5 7.2 7.2 Annual Mean 7.1 7.4 6.7 6.9 7.2 7.5 6.7 6.9 7.1 7.4 7.3 7.5 6.8 6.9 7.4 7.6 6.8 6.9 7.4 7.7 6.6 6.9 Alkalnity (rmg CaCO3IL)
Feb 14 16 14 16 15 16 14 18 15 16 14 16 14 16 15 16 14 16 14 16 14 16 May 15 13 14 15 14 13 14 13 14 13 14 13 14 14 14 13 14 15 14 14 14 15 Aug 15 16 15 16 15 15 15 15 14 15 14 16 19 18 14 15 15 16 14 16 15 16 Nov 15 16 22 16 16 16 17 17 16 16 16 16 17 16 16 17 18 16 16 15 16 15 Annual Mean 14.8 15.3 16.3 15.8 15.0 15.0 15.0 15.3 14.8 15.0 14.5 15.3 16.0 16.0 14.8 15.3 15.3 15.8 14.5 15.3 14.8 15.5 Chlonde (mg/L)
Feb 8.9 7.3 8.9 7.4 9.0 7.3 8.9 7.7 8..
7.3 8.8 7.2 6.7 7.1 9.0 7.4 8.9 7.3 8.3 10.0 7.1 9.1 May 8.6 8.3 8.7 8.2 8.6 8.2 8.8 8.1 8.9 8.4 8.9 8.3 8.7 8.3 8.8 8.3 8.8 8.6 8.4 9.7 8.4 9.3 Aug 7.1 9.0 8.0 8.3 6.9 8.8 8.0 8.3 7.0 9.0 6.9 9.0 7.7 8.4 7.2 8.9 8.1 8.4 7.3 10.0 7.8 8.5 Nov 7.0 9.4 7.2 9.4 7.1 9.5 7.3 9.4 7.2 9.5 7.2 9.5 7.2 9.4 7.2 9.4 7.5 9.4 7.1 9.8 7.3 9.6 Annual Mean 7.9 8.5 8.2 8.3 7.9 8.5 8.3 8.4 8.0 8.6 8.0 8.5 8.1 8.3 8.1 8.5 8.3 8.4 7.8 9.9 7.7 9.1 Sulfate (mg/L)
Feb 5.3 4.7 5.2 4.7 5.3 4.8 5.3 4.9 5.3 4.8 5.3 4.8 5.2 4.8 5.3 4.8 5.2 4.8 5.1 5.4 4.6 5.1 May 5.3 5.1 5.2 5.0 5.1 5.2 5.2 5.0 5.1 5.1 5.7 5.2 5.2 5.0 5.3 5.1 5.3 5.1 5.5 5.5 5.3 5.2 Aug 4.7 5.3 5.1 5.0 4.7 5.3 5.1 5.0 4.7 5.3 4.7 5.3 4.8 5.0 4.8 5.3 5.1 5.0 4.8 5.5 5.0 5.0 Nov 4.5 5.5 3.7 5.6 4.5 5.5 4.4 5.6 4.5 5.2 4.5 5.5 4.5 5.6 4.6 5.6 4.6 5.6 4.3 5.6 4.2 5.3 Annual Mean 5.0 5.2 4.8 5.1 4.9 5.2 5.0 5.1 4.9 9.1 5.1 5.2 4.9 5.1 5.0 5.2 5.1 5.1 4.9 5.5 4.8 5.2 Calcium (mg/L)
Feb 4.51 4.01 4.52 4.01 4.52 4.02 4.50 4.19 4.51 4.02 4.51 3.98 4.50 4.02 4.52 4.10 4.52 4.05 4.60 5.00 4.24 4.68 May 4.70 4.30 4.70 4.26 4.71 4.31 4.73 4.28 4.70 4.30 4.53 4.31 4.62 4.37 4.62 4.28 4.70 4.45 4.48 4.86 4.48 4.73 Aug 4.18 4.61 4.83 4.65 4.21 4.62 4.86 4.71 4.24 4.65 4.23 4.61 4.83 4.94 4.24 4.60 4.31 4.82 4.47 5.26 4.90 4.86 Nov 4.42 4.69 4.85 4.72 4.43 4.67 4.53 4.68 4.42 4.67 4.41 4.66 4.54 4.68 4.54 4.73 4.63 4.70 4.85 4.91 4.72 4.70 Annual Mean 4.45 4.40 4.73 4.41 4.47 4.41 4.66 4.47 4.47 4.41 4.42 4.39 4.62 4.50 4.48 4.43 4.54 4.51 4.60 6.01 4.59 4.74 Magnesiur (mg/L)
Feb 2.24 2.10 2.26 2.09 2.29 2.08 2.26 2.14 2.24 2.08 2.25 2.07 2.25 2.08 2.25 2.10 2.22 2.07 2.12 2.41 1.87 2.30 May 2.10 2.17 2.15 2.16 2.11 2.18 2.14 2.17 2.08 2.18 2.16 2.19 2.15 2.21 2.15 2.16 2.13 2.23 2.19 2.30 2.14 2.24 Aug 2.04 2.28 2.23 2.24 2.03 2.27 2.21 2.24 2.01 2.29 2.02 2.28 2.21 2.34 2.01 2.27 2.22 2.28 2.06 2.51 2.21 2.26 Nov 2.11 2.42 2.19 2.41 2.11 2.41 2.11 2.38 2.10 2.38 2.11 2.39 2.13 2.39 2.12 2.42 2.14 2.40 2.11 2.49 2.11 2.39 Annual Mean 2.12 2.24 2.21 2.23 2.14 2.24 2.18 2.23 2.11 2.23 2.14 2.23 2.19 2.26 2.13 2.24 2.18 2.25 2.12 2.43 2.08 2.30 t'J
0 Table 2-5 (Continued)
Mixing Zone
1.0 LOCATION
PARAMETERS YEAR' Mixing Zone 2.0 MNS Discharge 4.0 Surface Mixing Zone
5.0 Background
850 Surface Bottom
Background
11.0 Surface Bottom Surface 2009 2009 Bottom Surface Bottom Surface Bottom 20020091*
200 2000 2009 2000 2000 20001 200 20 2000 20001 2000 2Nix 2000 20001 2000 2000 2000 2000 Potassium (mrg/L)
Fab 2.00 1.97 2.01 1.96 2.01 1.96 2.01 1.90 2.05 1.96 2.04 1.94 2.01 1.97 1.98 1.95 2.01 1.05 1.98 1.98 1.94 1.95 May 1.98 1.93 2.01 1.90 1.98 1.93 2.00 1.92 1.94 1.91 2.04 1.93 2.02 1.92 2.03 1.90 1.99 1.91 1.97 1.88 1.93 1.87 Aug 1.94 1.94 1.96 1.94 1.94 1.98 1.96 1.96 1.91 1.92 1.86 1.92 1.99 1.99 1.94 1.94 1.94 1.91 1.87 1.88 1.95 1.85 Nov 2.02 2.02 2.07 2.01 2.05 2.02 2.05 1.99 2.05 2.05 2.04 2.03 2.04 2.00 2.05 2.01 2.07 2.05 2.05 2.02 2.04 2.01 Annual Mean 1.99 1.97 2.01 1.5 2.00 1.97 2.01 1.96 1.99 1.96 2.00 1.96 2.02 1.97 2.00 1.95 2.00 1.96 1.97 1.94 1.97 1.92 Soium (mg/L)
Feb 5.58 5.08 5.61 5,06 5.68 5.06 5.59 5.15 5.59 5.02 5.57 5.01 5.57 5.07 5.64 5.10 5.59 5.07 5.57 5.60 5.38 5.46 May 5.38 5.45 5.48 5.40 5.42 5.45 5.46 5.30 5.36 5.47 5.51 5.46 5.49 5.51 5.52 5.41 5.40 5.63 5.36 5.91 5.20 5.91 Aug 4.77 5.66 5.27 5.43 4.69 5.60 5.26 5.40 4.65 5.60 4.67 5.56 5.12 5.49 4.76 5.59 5.14 5.44 4.65 5.61 5.10 5.45 Nov 4.70 5.71 4.88 5.70 4.70 5.67 4.68 5.64 4.71 5.67 4.70 5.66 4.69 5.63 4.72 5.60 4.73 5.67 4.62 5.61 4.61 5.54 Annual Mean 5.11 5.48 5.31 5.40 5.12 5.45 5.25 5.40 5.08 5.45 5.11 5.42 5.22 5.43 5.16 5.43 5.22 5.45 5.05 5.68 5.07 5.59 Aluminum (mg/iL)
Feb 0.088 0.054 0.054 0.056 0.067 0.056 0.056 0.050 0.050 0.050 0.050 0.05 0.057 0.050 0.087 0.052 0.087 0.065 0.051 0.080 0.069 0.050 May 0.040 0.050 0.040 0.050 0.022 0.053 0.038 0.050 0.031 0.050 0.010 0.050 0.039 0.053 0.013 0,059 0.046 0.050 0.009 0.050 0.048 0.050 Aug 0.051 0.050 0.051 0.050 0.053 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.093 0.060 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 Nov 0.041 0.062 0.043 0.050 0.054 0.050 0.049 0.050 0.046 0.050 0.048 0.050 0.069 0.050 0.043 0.050 0.068 0.050 0.051 0.050 0.058 0.054 Annual Mean 0.055 0.054 0.047 0.052 0.049 0.052 0.048 0.050 0.044 0..SO 0.041 0.050 0.065 0.053 0.048 0.053 0.063 0.054 0.040 0.050 0.056 0.051 Iron (rng/L)
Feb 0.126 0.091 0.138 0.144 0.124 0.093 0.164 0.136 0.112 0.107 0.122 0.139 0.238 0.105 0.199 0.101 0.392 0.167 0.150 0.107 0.302 0.151 May 0.110 0.069 0.168 0.095 0.100 0.074 0.168 0.103 0.143 0.071 0.088 0.072 0.177 0.130 0.068 0.066 0.184 0.126 0.060 0.072 0.301 0.210 Aug 0.061 0.045 0.051 0.040 0.062 0.030 0.054 0.043 0.061 0.031 0.053 0.033 0.518 0.122 0.048 0.022 0.057 0.053 0.046 0.038 0.064 0.063 Nov 0.097 0.092 0.614 0.131 0.090 0.091 0.151 0.163 0.094 0.094 0.092 0.087 0.201 0.194 0.100 0.117 0.346 0.184 0.116 0.125 0.218 0.209 Annual Mean 0.090 0.074 0.243 0.102 0.096 0.072 0.134 0.111 0.102 0.076 0.089 0.083 0.284 0.138 0.104 0.077 0.245 0.133 0.003 0.086 0.221 0.158 Manganese (Ug/L)
Feb 13 1t 24 34 16 11 21 18 18 13 16 25 38 12 13 10 31 15 17 19 43 27 May 9
5 30 12 10 5
33 16 11 6
10 6
46 29 6
4 32 20 7
4 48 48 Aug 33 16 292 205 40 10 349 305 55 21 46 18 1800 1440 23 12 538 564 23 35 669 523 Nov 41 37 2130 50 45 37 08 106 46 37 44 38 216 105 41 28 676 60 52 46 86 75 Annual Mean 24 17 619 77 28 17 123 111 32 10 29 22 525 397 21 13 319 160 25 26 212 168 Cacinhu (ugIL)
Feb 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 May 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Aug 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 0.5 Nov 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1,0 1.0 1.0 1,0 1.0 1.0 t10 1.0 1.0 Annual Mean 0.9 0.6 0.9 0.6 0.9 0.625 0.9 0.6 0.9 0.6 0.9 0.6 0.9 0.6 0.9 0.6 0.9 0.6 0.9 0.6 0.9 0.6 Copper (ug/L)
Feb 1.6 2.0 1.7 2.0 1.7 2.0 1.6 2.0 1.7 2.0 1.7 2.0 1.8 2.0 1.6 2.0 2.0 2.0 2.3 2.8 2.0 2.3 May 2.5 2.0 2.3 2.0 2.3 2.0 2.3 2.0 2.4 2.0 2.2 2.0 2.2 2.0 2.0 2.0 2.2 2.0 2.2 2.2 2.5 2.2 Aug 1.4 2.0 1.2 2.0 1.5 3.7 1.1 2.0 1.6 2.3 1.5 2.3 1.0 2.0 1.3 2.0 1.1 2.0 2.2 2.9 2.0 2.1 Nov 1.8 1.5 1.0 1.4 1.0 1.5 1.0 1.4 1.0 1.6 1.0 1.5 1.0 1.5 1.0 2.1 1.0 2.0 1.9 3.3 1.8 2.1 Annual Mean 1.8 1.9 1.5 1.0 1.6 2.3 1.5 1.9 1.7 2.0 1.6 1.9 1.5 1.9 1.5 2.0 1.6 2.0 2.2 2.8 2.1 2.2 Lead (ug/L)
Feb 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 1.0 May 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 1.0 Aug 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 2.0 1.0 1.0 Nov 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 10 1.0 1.0 1.0 1.0 Annual Mean 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.8 1.0 1.0 f~jJ
Table 2-5 (Continued)
LOCATION:
PARAMETERS YEAR:
Mixing Zone 1.0 Surface Bottom 2009 2008 2009 2008 Mixing Zone 2.0 Surface Bottom 2009 2008 2009 2001 MNS Discharge 4.0 Surface 2009 2008 Mixing Zone
5.0 Background
8.0
Background
11.0 Surface Bottom 2009 2008 2009 2008 Surface Bottom Surface Bottom 2009 2008 2009 2008 2009 2008 2009 2008 Zinc (ughL)
Feb May Aug Nov Annual Mean 1.3 1.5 1.3 1.7 1.5 2.2 1.3 4.2 10.8 1.3 6.1 1.2 1.5 1.0 1.7 1.0 3.8 1.5 2.6 2.0 1.2 2.5 1.6 1.U 1.0 1.7 1.1 2.3 7.5 2.1 7.9 1.4 1.9 1.0 1.5 1.1 2.9 1.8 3.0 U.?
1.6 1.8 1.2 2.0 6.6 1.5 1.4 1.0 2.7 1.6 1.4 1.7 1.8 2.2 1.1 22 1.2 2.8 11.9 1.1 11.3 1.0 1.6 1.0 2.7 1.0 4.0 1.5 43 1.7 1.1 1.9 1.5 28 1.0 3.2 1.2 20 6.5 1.0 9.6 1.2 1.6 1.4 1.9 1.3 2.6 1.9 3.6 1.8 1.5 4.0 1.8 1.9 1.1 2.0 1.5 2.2 10.8 1.3 12.3 1.1 4.6 1.5 2.0 1.4 4.5 2.2 4.4 1.6 Nitrite-Nitrate (ug(L)
Feb May Aug Nov Annual Mean 89 150 99 130 200 280 240 510 65 150 290 390 48 110 320 110 101 173 237 285 88 140 91 16C 190 450 240 30C 76 150 280 37C 49 120 59 96 101 215 168 232 90 150 200 340 81 150 50 110 105 188 91 150 100 140 140 450 240 240 77 180 130 300 52 110 55 110 90 218 131 198 87 140 110 140 140 250 260 300 45 140 260 360 58 120 52 100 83 163 171 225 200 210 230 290 150 510 290 640 21 110 240 370 120 150 120 110 123 245 220 353 Ammonia (ugh)
Feb 33 120 33 83 28 130 28 130 29 140 29 59 33 150 26 81 33 94 26 71 53 92 May 32 270 25 210 65 200 20 250 37 190 24 200 24 280 110 270 41 280 54 220 210 240 Aug 45 20 66 20 36 20 51 20 36 20 39 20 120 55 73 24 33 20 34 20 84 25 Nov 130 50 300 57 130 59 160 78 140 120 150 61 180 55 210 45 200 79 130 48 140 76 Annual Mean 60 115 106 93 65 102 65 120 61 118 61 85 89 135 105 105 77 118 34 90 122 108 Total Phosphorous (ughL)
Feb 8
6 11 6
9 6
10 6
10 6
8 6
11 6
8 6
12 6
11 6
15 7
May 12 8
11 7
11 7
11 7
12 7
10 8
12 7
11 7
11 7
12 8
13 9
Aug 10 7
7 6
10 7
7 6
9 7
9 7
9 7
8 6
11 7
9 8
27 8
Nov 8
8 10 8
6 7
7 8
7 8
5 7
9 8
8 5
20 8
10 9
10 8
Annual Mean 9
7 10 7
9 7
9 7
9 7
8 7
10 7
9 6
14 781 8
16 8
Orthophosphate (ughL)
Feb 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
6 May 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 Aug 5
5 5
5 5
7 5
5 5
6 5
5 5
5 5
5 5
5 5
5 5
5 Nov 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 Annual Mean 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 5
5 Silicon (rng/L)
Feb 3.8 4.9 3.8 5.0 3.7 4.9 3.7 5.2 3.6 5.0 3.6 5.0 3.8 5.0 3.6 5.0 3.7 5.0 4.0 5.3 4.2 5.3 May 4.1 5.1 4.3 5.0 4.0 4.9 4.3 5.2 4.0 4.9 4.0 4.9 4.4 5.2 4.1 4.8 4.6 5.2 3.9 4.8 4.4 5.4 Aug 3.8 4.5 4.7 5.3 3.8 4.4 4.9 5.4 3.8 4.4 3.8 4.4 5.1 5.5 3.7 4.4 4.9 5.5 3.7 4.4 4.8 5.4 Nov 4.0 5.0 4.5 4.9 4.0 4.9 4.0 4.9 4.0 4.9 4.0 5.0 4.1 5.0 3.9 4.8 4.2 5.0 4.1 4.7 4.2 4.9 Annual Mean 3.9 4.9 4.3 5.1 3.9 4.8 4.2 5.2 3.9 4.8 3.8 4.8 4.4 5.2 3.8 4.8 4.3 5.2 3.9 4.8 4.4 5.3 0'-)
'1.
NC C3420'000 69.0 0
Water Quality Sampling Locations 15 Ma all Steam Statilo 13.
N
,62.0 J,
,I) 7'15.9
'I' i
.L *i~
+
%A 00.51 2
3 OMiles 0 1 2 4
Kilometers Cowans Ford DamnIW McGuire Nuclear Station Figure 2-1. Water quality sampling locations (numbered) for Lake Norman. Approximate locations of Marshall Steam Station and McGuire Nuclear Station are also shown.
2-25
E CD U,
0*
180 160 140 120 100 80 60 40 20 n
I__
_it I I I
I
. 50 Ui I I I
m I
I 70 60 m
40 30 0-C.,
30-20 10 0
Figure 2-2a. Annual precipitation totals in the vicinity of MNS.
25 1 20 15 CD E
10 5
U,-
U 0
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Figure 2-2b. Monthly precipitation totals in the vicinity of MNS in 2008 and 2009.
2-26
30 28 26 24 22 20
~18 o16 CL14 E
S 12 o10 8
6 X0 4
2 0 r=
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Long-term average N52008 2009 Figure 2-2c. Mean monthly air temperatures recorded at MNS beginning in 1989. Data were complied from average daily Qtemperatures which, in turn, were created from hourly measurements.
JAN TemperOte CC) 0 5
10 15 2X 25 30 35 FEB Teratfir CC) 0 5
10 15 20 25 30 35 MAR TeMperAtu 3C) 0 5
10 15 20 25 30 35 APR 0
5 10 15 20 25 30 35 MAY Tomerat (C) 0 5
10 15 20 25 30 35 JUN 0
5 10 15 20 25 30 35 0
5 10 115
%20 25 165 S 20 a
00 Figure 2-3. Monthly mean temperature profiles for the MNS background zone in 2008 (xx) and 2009 (**).
JUL Temperfe (C) 0 5
10 15 20 25 30 35 AUG Tuqeratfe (C) 0 5
10 15 20 25 30 35 SEP Temperature fC) 0 5
10 15 20 25 30 35 e,
0 5
10 15
[0 25 30 35 OCT Temperaure (C) 0 5
10 15 20 25 30 35 NOV TWeaM O (C) 0 5
10 15 20 25 30 35 DEC Tempe*iature C) 0 5
10 15 20 25 30 35 0
5 10 S15 120 25 30 35 0
5 10 15 120 25 3D 35 Figure 2-3. (Continued).
0 JAN Tempefatue CC) 0 5
10 15 20 25 30 35 FEB Tape'mu CC) 0 5
10 15 20 25 30 35 MAR Tunperatwe CC) 0 5
10 15 20 25 30 35 0
5 10
?15 25 30 35 0
5 ID 20 25 30 35 0
5 10 I20 25 30 35 APR Ternpa"fliO CC) 0 5
I1 15 20 25 30 35 MAY Temperature (C) 0 5
10 15 20 25 30 35 JUN Tenm Ure TC) 0 5
10 15 20 25 30 35 5
10
- 12 25 3D 35 0
5 10 E15 120 25 30 35 0
Figure 2-4. Monthly mean temperature profiles for the MNS mixing zone in 2008 (xx) and 2009 (**).
JUL Tmwierae CC) 0 5
10 15 20 25 30 35 AUG Tear*ta e CC) 0 5
10 15 20 25 30 35 SEP Taergrne CC) 0 5
10 15 20 25 30 35 10
,5 25 0
5 10 25 30 35 OCT TewWeramwe f'C) 0 5
10 15 20 25 30 35 NOV TeMneatil fC) 0 5
10 15 20 25 30 35 DEC Tmeer#ur fCC) 0 5
10 15 20 25 30 35 115 12D 25 30 35 o
5 10 115 25 30 35 Figure 2-4. (Continued).
45 40 35
-30 25 L-20 CL
~15-10 5
0
-O-- 2008
-'-2009 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month
-J E
C0)
X 0
'V 0W o
o0 12 11 10 9
8 7
6 5
4 3
2 0
2008 2009 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month Figure 2-5. Monthly surface (0.3m) temperature and dissolved oxygen data at the discharge location (Location 4.0) in 2008 and 2009.
2-32
JAN DiswoWe Oxygen L 0
2 4
0 8
10 12 FED 2 4 oxygen 8tm1) 0 2
4 8
8 10 12 MAR DWsOlve Oxygen MAL 0
2 4
6 8
10 12 0
5 t0
,15 20 25 30 35 0
5 10 120 25 3D 35 0
5 10 t15 120 25 30 35 APR Dissulme Oxygen (ngfl4 0
2 4
6 8
10 12 MAY DIssolved Oxygen (mi) 0 2
4 6
8 10 12 JUN DIo=ved Oxygen MW 0
2 4
6 8
10 12 0
5 10
!15 25 30 35 0
5 10 120 25 30 35 Iij Figure 2-6. Monthly mean dissolved oxygen profiles for the MNS background zone in 2008 (xx) and 2009 (* *).
JUL Dissolved Oxygen 6
mg 0
1 0
2 4
6 8
10 12 AUG Di0n2 Oxygen O8 0
2 4
8 8
0 2
4 8
a 10 12 0
5 10 E15 2D 30 35 0
6 10
.2D 25 30 35 10 1L0 25 30 36 OCT NOV Dissolved Oxygen (m*g4 Dissolved Oxygen (ngWLW 0
2 4
6 8
10 12 0
2 4
6 8
10 12 DEC Dissonved Oxygen #mIgj 0
2 4
6 8
10 12 10 DS 35 I")
Figure 2-6. (Continued).
JAN issov oxygen (Vr*
0 2
4 6
8 10 12 FEB 2 solved Oxygen 610 1
0 2
4 8
8 10 12 MAR Disso" d Oxygen OMN; 0
2 4
6 8
10 12 0
5 10 215 120 25 30 35 0
5 10
[15 2D 25 30 35 0
5 10
[15 20 25 3D 35 APR DIssolved Oxygen (mXA 0
2 4
6 8
10 12 MAY DsOIld Oxygen #n%14 0
2 4
6 8
10 12 JUN Dissolved Oxygen (mng) a 2
4 6
8 10 12 0
5 10 120 25 3D 36 0
5 1L0 25 30 35
,?
Figure 2-7. Monthly mean dissolved oxygen profiles for the MNS mixing zone in 2008 (xx) and 2009 (* *).
JUL Di2 led Oxygen 81 0
2 4
8 8
10 12 AUG Dsoved Oxygen (ng 0
2 4
6 8
0 2
4 8
8 10 12 10 12 0
5 10 115 r.2 25 35 OCT DIssoved Oxygen m44LI 0
2 4
6 8
10 12 NOV DssoPd Oxygen MIL) 0 2
4 a
8 10 12 DEC Dsoled Oxygen nLJ 0
2 4
6 8
10 12 115
.20 a
10 25 10 35 t*
Figure 2-7. (Continued).
.- 22 22 22 2
221 21 21 20 20 20 Temperature (0 C) 20 Jan 9, 2009 0
1"o
-IS 20 25 30 35 40 45
.50 55 Distance from Co.wans Ford Dom (km) 242 240 Sampling Locations 23
.0 8.0 11.0 13.0 ISO 15.5 62.0 69.0 720.
80,0 23 1,0 22
/2 220* *¢*I*
- --*23 22 22 21 1 i 21 21 20 20 20 Temperature (0o C) 20o Mar6,22009 519 10' A
15 203025 3
35 401 45 50 55 Distance from Cowans Ford Daon (kin) t Figure 2-8. Monthly reservoir-wide temperature isotherms for Lake Norman in 2009.
-,.I Distance from Cowaens Ford Dam (kin)
Distance from Cowans Ford Da.
(krn)
Sampling Locations Sampling Locations 23 1.0 6.0 11.0 13.0 16.0 15'9 62.0 69.0 72.0 60.0 235 1,0
.0 11.0 13.0 15.0 10.0 62.0 69.0 72.0 60.0 23 23 222 S22 22 I
___:~~
_E
_E-14 11 210 2j 18...
T0e mpe-tu (0
Temperature (° C) 20o Temperature(U C) 20Juo1o2 0
May 5, 2009 10 155 20 25 300 35 40' 45 50' s
5 35 255 195~~~~~~~~3 354 40 450 10 55
~
A 1711 S
=
6 itefomC odDm(m Distance from Cowans Ford Dam (kim) 0istanoe from Cowanl Ford Darn (kin) 4 Samplu Locatio ns Sampling Locations 23 1.0 6.0 11.0 13,0 15,0 15.9 02,0 09.0 72.0 so00 23 1.0 6.0 11.0 13.0 15.0 15.0 62.0 690 72.0 sol0 k23 2 3 2 9
__ ~ -~27 7
[1212_
_6 211..
21 14--
20 2
20~~J Teprtr 0C Temperature (I C)
J0Tmeaule 6,
C 200 Aug 3, 2009 0............10695120 25 130 150 401 45 510 55tac 10o 15an 20r 2a5 30 35 4k4 0
)
Distance from Cowans Ford Dam (kmn)Dltn.fmCwasorDm(i)
S Figure 2-8. (Continued).
00
I I
Oistance from Cowans Ford Dam (kin)
Distance from Cowans Ford Dam (kin)
L*
Distance from Cowans Ford Dam (kin)
Figure 2-8. (Continued).
Distance from Co-ans Ford Dam (kin)
23&'
23,--
225-215'"
I 210-20!;
20C-240 23&-
230>-
225-22o-
- 210, 205.
- 200, 1.0
&0 11,0 Sampling Locatons 13.0 15.0 15.9 02.0 09.0 4
£ 4
4 4
23 1,0 80 11.0 13,0 15.0 15.9 62.0 69.0 72,0 80.0 72ýO 60,0 Dissolved Oxygen (mg0L)
Jan 9,
2009 225-S220-215'-
210-205-200-Dissolved Oxygen (mg/L)
Feb 2, 2009 I-.....................
Distance from Cowans Ford Dam (kin)
Sampling Locations 13,0 15.0 15.9 62,0 89.0 I
I I
i I
,.o 8.0 110 4
4 72.0 0.0 10I Dissolved Oxygen (mgIL)
Mar 6, 2009 I
105g 9
4, 0
S l
.0,01 40 991, 0
0030.
35 40 93 5
50 5
Distance from Cowans Ford Dam (kin) 24 Samplingr~ Locations 23 1.0 8.0 11.0 13.0 15.0 1519 62.0 69.0 72.0 80.0 230 215 21 20 20 Dissolved Oxygen (mg/L)
Apr 13, 2009 19~ I.
I-t,,J J0
-. 11 o....
- Zi..
o A
o....
.415.
Vs I I V 10 Distance from Cowans Ford Dam (kin)
Figure 2-9. Monthly reservoir-wide dissolved oxygen isopleths for Lake Norman in 2009.
IS 20 2* 5 3 0 VA 3r 401 145 in5 Distance from Cowans Ford Dam (kin)
240A-Sampling Locations Sampling Locations 23 1.0
.0 1,.0 13.0 16,.0 1*0.
2.0 89.0 72.0 80*0 23 1.0 8.0
- 1.
13.0 15.0 15.9 82,0 8l.0 72.0
- 80. 0 i
4-
<4.4. 4 4.
........4 23 9'"
'2333 Q
220 22 21
.21 2=o Dissolved Oxygen (mg/L) 20 Dissolved Oxygen (mglL)
May 5, 2009 Jun 1, 2009 10 15 20 2
30 35 4
- 151 1
1 20 25 3
35 40 Distance from Cowens Ford Dom (kin)
Distance from Cowans Ford Dam (kmi) 240 240 Sampling Locations Sampling Locations 23 1.0 8.0 11.0 13.0 15.0 15.9 62.0 69.0 72.0 s0o0 23 1,0 8.0 11.0 13.0 15.0 1e.9 62.0 69.0 12.0 80.0 4~~~~~~~l
-b N ft 41 41.
23 2
2~-2 22-21 2
21 21 20 Dissolved Oxygen (mg/L)
Dissolved Oxygen (mg/L)
Jul 6, 2009 Aug 3, 2009 10 15 27027 37 315 A II 150 5'505 10 1 5 20
'2'5...
3'0 35' 40 45 50 5
Distance from Cowans Ford Dam (kin)
Distance from Cowans Ford Dam (kin)
Figure 2-9. (Continued).
Z4u
',V Sampling Locations Sampling Locations 23 1.0 0.0 110 130 15,0 15.
62.0 6.0 72.0o 0.0 23 10
.0 11.0 13.0 15.0 s
.s 62,0 G9.0 72.0
.0o o 23 a23 21 21 205o 20 a
Dissolved Oxygen (mg/L)
Dissolved Oxygen (mg/L)
Oct 6, 2009 10 15 2
2 5
3 3' 5 40 45 110' 55 2.0 A
A 0 A
Z I V I. A..
Distance from Cowans Ford Dam (kim)
Distance from Cowans Ford Dam (klm) 24 240" Sampling Locations Sampling Locations 23 1.0
- 0.
11.0 13,0 ISO10 s9 62o0 69,0 72,0
$Or0 23
,o0 8,0 i11.
13.0 15.0 15,9 02.0 00.,0 72,0 00.
23 1 b 23
-b 22
/
2ao C,.....
220 j21 21 21 21 205 20 Dissolved Oxygen (mg/L)
Dissolved Oxygen (mg/L)
Nov 2, 2009 Dec 8,2009 0
5 10 15 20 25 30 35 40 45 50 55 25 30 35 40 45 9
1 Distance from Cowans Ford Dam (kim)
Distance from Cowans Ford Dam (kin)
Figure 2-9. (Continued).
35 N
E~
30-25 20 15 0,
Cr",
0 0,ý00r, C10-0. 0, a0-10-5
'I 0
50 100 150 200 250 300 350 Julian Date Heat content of the entire water column (0) and the hypolimnion (o) in Lake Norman in 2009.
Figure 2-10a.
12
-J E
C
>1 00 0
10 8
6 4
2 100 90 80 70 60 50 40 30 20 10 0
C
.2 U)
(D CL 0
1 31 61 91 121 151 181 211 241 271 301 331 Julian Date Figure 2-1Ob. Dissolved oxygen content (-) and percent saturation (---) of the entire water column (a) and the hypolimnion (o) of Lake Norman in 2009.
2-43
24(
240 i
LA*KE NORMAN STRIPED BASS HABITAT LAK NORMAN STRIPED BASS HABITAT 23 810 IC0 13,0 15.0 15*9 62.0 69.0 72.0 W00 23 10
.0 11,0 13.0 1W.0 15,9 62,0 69,0 72.0 W0.0 23 223
,22
,"22 22 22 21 2o;?1 22g/1 20 26 OC 2026O 2
D2 mg/L DO 20 Jun 22, 2009 20 Jun 29, 2009 0
14 2 0 A
1 3 7 0 0
4 5 V I I o5 V6-2-
3 0 3 5 4 0 4 5 0
0 Dis*an)e from Cao.ans Ford Darn (kin)
Distance from Cowans Ford Dam (kin) 24 240 LAKE NORMAN STRIPED BASS HABITAT LAKE NORMAN STRIPED BASS HABITAT 23 1.0
.0C 11.0 13.0 15.0 15.9 62.0 690 72.0 900 23 1,0 6.0 11,0 13.0 15.0 15.9 62A 6910 72.0 80.0 23 23 222 22 22 21o 21o 20 26:* 'C....
20,o 26 O C 2
0 2
2 mgtL DO Jul 6, 2009 Ju114, 2009 V
1.20 T
70 75, 0
4 75 70 5'i' 1
01 A
37 30 35 40 45 0
0 Distance from Cowans Ford Dam (kin)
Dlsftano from Cowans Ford Dam (kin)
S Figure 2-11. Striped bass habitat (shaded areas; temperatures < 26 'C and dissolved oxygen > 2 mg/L) in Lake Norman in June, July, t
August, and September 2009.
24 LAKE NORMAN STRIPED BASS HABITAT 8.0 I.0
- 3.
1,. 15..
8 62.0 68.0o 20 8.
1.0
'o 72.0 80.0 I
I Distano-fr"m Cowans Ford Dam (ktm) 230.
225.
220-215-:
20!5.
200-195" 240.
235.
230.
225.
225.
i 215" 210o 205.
205>
0 115 ---- 270 ---- 25....
3YO ---- A ---- 4V 4.;S.
5"o A
Dislance fram Cowan. Ford Dam (k-i)
~26
'C f
2 mg/L DO
~Aug 17, 2009 LAKE NORMAN STRIPED BASS HABITAT 1.0 8.0 llo 13.0 15,0 15.9 62,0 69.0 72.0 8,o0 26 0 C
~2 mmgtL DO Oct 6, 2009 195 10 15 20 25 30 35 40 45 50 55 DIstance from Cowans Ford Dam (kin)
Daitance from Cowans Ford Dam (kin)
%J LtA Figure 2-11. (Continued).
0 232.0 Full Pond @ 231.65 mmsl 231.5 E
"Z 230.5 230.0 229.5 2 2 9.0 Figure 2-12. Lake Norman lake levels, expressed in meters above mean sea level (mmsl) for 2002, 2003, 2004, 2005, 2006, 2007, 2008, and 2009. Lake level data correspond to the water quality sampling dates over this time period.
10.00 9.50 9.00 8.50 8.00
, 7.50 7.00 I
6.50 6.00 5.50 5.00 1/4/99 1/4/00 1/4/01 1/4/02 1/4/03 1/4/04 1/4/05 Date 1/4/06 1/4/07 1/4/08 1/4/09 Figure 2-13. Lake Norman pH values for Locations 62.0 and 69.0 over period 1999-2009. Also included are corresponding descriptive statistical data.
CHAPTER 3 PHYTOPLANKTON INTRODUCTION Phytoplankton standing crop parameters were monitored in 2009 in accordance with the NPDES permit for McGuire Nuclear Station (MNS). The objectives of the phytoplankton study of the Lake Norman Maintenance Monitoring Program are to:
- 1. describe quarterly/seasonal patterns of phytoplankton standing crop and species composition throughout Lake Norman; and
- 2. compare phytoplankton data collected during the 2009 study with data collected in prior study years (1987 - 2008).
In studies conducted on Lake Norman prior to the Lake Norman Maintenance Monitoring Program, considerable spatial and temporal variability in phytoplankton standing crops and taxonomic composition were reported (Duke Power Company 1976, 1985; Menhinick and Jensen 1974; Rodriguez 1982). Rodriguez (1982) classified the lake as oligo-mesotrophic (low to intermediate productivity) based on phytoplankton abundance, distribution, and taxonomic composition. Past maintenance monitoring program studies have confirmed this classification (Duke Energy 2009).
METHODS AND MATERIALS Quarterly sampling was conducted at Locations 2.0 and 5.0 in the Mixing Zone, and Locations 8.0, 9.5, 11.0, 13.0, 15.9, and 69.0 in Lake Norman (Figure 2-1). Duplicate Van Dorn samples from 0.3, 4.0, and 8.0 m (i.e., the estimated euphotic zone) were taken and then composited at all locations except Location 69.0, where Van Dorn samples were taken at 0.3, 3.0, and 6.0 m due to the shallower depth. Sampling was conducted in February, May, August, and November 2009. Secchi depths were recorded from all sampling locations. As in previous years and based on the original study design (Duke Power Company 1988),
phytoplankton density, biovolume, and taxonomic composition were determined for samples collected at Locations 2.0, 5.0, 9.5, 11.0, and 15.9; chlorophyll a concentrations and seston dry and ash-free dry weights were determined for samples from all locations. Chlorophyll a 3-1
and total phytoplankton densities and biovolumes were used in determining phytoplankton standing crops. Field sampling and laboratory methods used for chlorophyll a, seston dry weights, and population identification and enumeration were identical to those used by Rodriguez (1982).
Data collected in 2009 were compared with corresponding data from quarterly monitoring beginning in August 1987.
RESULTS AND DISCUSSION Standing Crop Chlorophyll a Chlorophyll concentrations from all locations were averaged each quarter to calculate a lake-wide mean. Lake-wide mean chlorophyll concentrations were within ranges of those reported in previous years, but the lake-wide mean for November was very near the long-term minimum for that time of year (Figure 3-1). The lake-wide average in February was above the long-term mean, while averages for May and August were below long-term means for these periods.
Chlorophyll a concentrations (mean of two replicate composites) ranged from a low of 1.53 gtg/L at Location 69.0 in November, to a high of 13.24 jgg/L also at Location 69.0 in August (Table 3-1 and Figure 3-2). All values were below the North Carolina water quality standard for outfalls of 40 tig/L (NCDENR 1991). Seasonally, chlorophyll a concentrations decreased from February through May, and then increased through August to the annual lake-wide maximum followed by a decline to the annual lake-wide minimum in November. Based on quarterly mean chlorophyll concentrations, the trophic level of Lake Norman was in the oligotrophic (low) range during May and November and in the mesotrophic (intermediate) range in February and August of 2009. Over 37% of the mean chlorophyll a values were less than 4 gg/L (oligotrophic), while all but one of the remaining chlorophyll a values were between 4 and 12 pgg/L (mesotrophic). The chlorophyll concentration from Location 69.0 in August was the only one greater than 12 gg/L (eutrophic, or high range).
Historically, quarterly mean concentrations of <4 ptg/L have been recorded on 22 previous occasions, while lake-wide mean concentrations of >12 gtg/L were only recorded during May of 1997 and 2000 (Duke Power 1998, 2001; Duke Energy 2009).
3-2
During 2009, chlorophyll a concentrations showed typical spatial variability. Maximum concentrations among sampling locations were observed at Location 69.0 (furthest uplake) during February and August, while the May and November maxima were recorded from Location 15.9 (Table 3-1 and Figure 3-1). Minimum concentrations occurred at Locations 2.0, 5.0, and 8.0 during February, May, and August, respectively.
The minimum in November occurred at Location 69.0 The trend of increasing chlorophyll concentrations from downlake to uplake, which had been observed during many previous years, was apparent for the most part during all sampling periods of 2009 (Table 3-1 and Figure 3-1).
Flow in the riverine zone of a reservoir is subject to wide fluctuations depending, ultimately, on meteorological conditions (Thornton et al. 1990), although influences may be moderated due to upstream dams. During periods of high flow, algal production and standing crop are depressed due in great part to washout. Conversely, production and standing crop increases during periods of low flow which results in high retention time. However, over long periods of low flow, production and standing crop gradually decline once more. These conditions result in the comparatively high variability in chlorophyll a concentrations observed between Locations 15.9 and 69.0 throughout many previous years, as opposed to Locations 2.0 and 5.0 which have usually shown similar concentrations during sampling periods.
Quarterly chlorophyll a concentrations during the period of record (August 1987 - November 2009) have varied considerably, resulting in moderate to wide historical ranges. During February 2009, chlorophyll a values were in the mid to high ranges for this time of year (Figure 3-3). Long-term February peaks at Locations 2.0, 5.0, 8.0, and 9.5 occurred in 1996, while the long-term February peak at Location 11.0 was observed in 1991.
Long-term maxima at Locations 13.0 and 15.9 occurred in 2003. The highest February value at location 69.0 occurred in 2001.
All locations demonstrated higher chlorophyll concentrations in February 2009 than in February 2008 (Duke Energy 2009).
During May, mean chlorophyll a concentrations at all locations were in the low to mid historical ranges (Figure 3-4). Long-term May peaks at Locations 2.0 and 9.5 occurred in 1992; at Location 5.0 in 1991; at Locations 8.0, 11.0, and 13.0 in 1997; at Location 15.9 in 2000; and at Location 69.0 in 2001.
May 2009 mean chlorophyll concentrations at all locations were higher than those of May 2008 (Duke Energy 2009).
The lake-wide mean chlorophyll a concentration in August 2009 was slightly below the long-term mean for August. Concentrations from all but Location 8.0 were in the mid historical 3-3
range. The concentration from Location 8.0 was among the lowest August concentrations yet recorded from this location (Figure 3-5). Long-term August peaks at Locations 2.0, 5.0, and 15.9 were observed in 1998, while August peaks at Locations 8.0 and 9.5 occurred in 1993.
The long-term August peak at Location 11.0 was observed in 1991, while Location 69.0 experienced its long-term August peak in 2001.
The long-term peak at Location 13.0 occurred in 2008. Mean chlorophyll a concentrations at Locations 2.0, 5.0, 9.5, 15.9, and 69.0 in August 2009 were higher than those of August 2008, while Locations 8.0, 11.0, and 13.0 expressed lower concentrations in August 2009 than in August of the previous year (Duke Energy 2009).
The lake-wide mean chlorophyll a concentration in November 2009 was the lowest among all four sampling periods and was very near the long-term November minimum (Figure 3-2).
Chlorophyll a concentrations at locations were in the low historical range (Figure 3-6).
Long-term November peaks at Locations 5.0 and 8.0 occurred in 2006, while November maxima at Locations 11.0 and 15.9 occurred in 1996.
The highest November value at Location 13.0 was recorded for 1992, while the November maxima at Locations 2.0 and 9.5 were observed in 1997. The highest November chlorophyll a concentration at Location 69.0 occurred in 1991.
November 2009 chlorophyll a concentrations were lower than during November 2008 (Duke Energy 2009).
Total Abundance Density and biovolume are measurements of phytoplankton numbers and biomass. In most cases, standing crop parameters mirror the temporal trends of chlorophyll concentrations.
During 2009 this was not entirely the case.
Although phytoplankton densities and biovolumes were typically highest in August, as was the case with chlorophyll a, mean standing crop variables demonstrated lowest annual values in May instead of November. The lowest densities (536 units/mL) were recorded from Locations 2.0 and 5.0 in May, while the minimum biovolume (294 mm3/m3) occurred at Location 2.0 also in May (Table 3-2 and Figure 3-1). The maximum density (4,569 units/mL) and biovolume (3,855 mm 3/m3) were observed at Location 15.9 in August. Densities during May, August, and November of 2009 were lower than those observed during these periods of 2008. Biovolumes during February, May, and August of 2009 were higher than in 2008 (Duke Energy 2009). This disparity was likely due to taxonomic variations from year to year with shifts from taxa with lower individual biovolumes to those with higher individual biovolumes. Phytoplankton densities and biovolumes during 2009 never exceeded the NC state guidelines for algae blooms of 3-4
10,000 units/mL density and 5,000 mm 3/m 3 biovolume (NCDEHNR 1991). Densities or biovolumes in excess of NC state guidelines were recorded in 1987, 1989, 1997, 1998, 2000, 2003, 2006, and 2008 (Duke Power Company 1988, 1990; Duke Power 1998, 1999, 2001, 2004a; Duke Energy 2007, 2009).
During all sampling periods phytoplankton densities and biovolumes demonstrated a spatial trend similar to that of chlorophyll a; that is, lower values at downlake locations verses uplake locations (Table 3-2 and Figure 3-1).
Seston Seston dry weights represent a combination of algal matter and other organic and inorganic material. Dry weights during February and May of 2009 were most often higher than those recorded during these months in 2008, while August and November values in 2009 were generally lower than August and November of 2008 (Duke Energy 2009 and Table 3-3). A general pattern of increasing values from downlake to uplake was observed during May and August 2009, as was observed with chlorophylls and algal standing crops; however, in February and November, this pattern was not pronounced even though Location 69.0 demonstrated the highest dry weights (Figure 3-1). From 1995 through 1997, seston dry weights had been increasing (Duke Power 1998).
Values from 1998 through 2001 represented a reversal of this trend, and were in the low range at most locations during 1999 through 2001 (Duke Power 2002). Low dry weights during these years were likely a result of prolonged drought conditions (Figure 2-2a) resulting in low sedimentation from runoff.
From 2002 through 2006 dry weights gradually increased throughout the Lake followed by a dramatic decline in 2007. The lake-wide average dry weight in 2007 was the lowest since dry weights were recorded in 1988. These exceptionally low values were likely due to severe drought conditions throughout the watershed during 2007.
During 2008, dry weights increased again compared to 2007. This was followed by a slight decline in 2009.
Seston ash-free dry weights represent organic material and may reflect trends of chlorophyll a and phytoplankton standing crop values. This relationship held true for May and August of 2009, especially with respect to increasing values from downlake to uplake areas; however, as with dry weights, this trend was not apparent in February and November (Tables 3-1 through 3-3). Ash-free dry weights also showed the same temporal trend as dry weights when compared to 2008 with values in February and May 2009 higher than in 2008, while the opposite was true in August and November (Duke Energy 2009).
3-5
Secchi Depths Secchi depth is a measure of light penetration.
Secchi depths were often the inverse of suspended sediment (seston dry weight), with the shallowest depths at Locations 13.0 through 69.0 and deepest from Locations 9.5 through 2.0 downlake. Depths ranged from 1.1 m at Location 69.0 in August, to 2.8 m at Location 8.0 in May (Table 3-1). The lake-wide mean Secchi depth during 2009 was slightly lower than in 2008 and was within historical ranges for the years since measurements were first reported in 1992. The deepest lake-wide mean Secchi depth was recorded in 1999 (Duke Power 2000).
Community Composition One indication of "balanced indigenous populations" in a reservoir is the diversity, or number of taxa observed over time.
Lake Norman typically supports a rich community of phytoplankton species. This was certainly true in 2009. Ten classes comprising 99 genera and 271 species, varieties, and forms of phytoplankton were identified in samples collected during 2009, as compared to 98 genera and 247 species, varieties, and forms of phytoplankton identified 2008 (Table 3-4). The 2009 total represented the highest number of taxa recorded in any year since monitoring began in 1987 (Duke Energy 2008). Ten taxa previously unrecorded during the Lake Norman Maintenance Monitoring Program were identified during 2009.
Species Composition and Seasonal Succession The phytoplankton community in Lake Norman varies both seasonally and spatially.
Additionally, considerable variation may occur between years for the same months sampled.
During February 2009, diatoms (Bacillariophyceae) dominated densities at all locations (Table 3-5 and Figures 3-7 through 3-11).
During most previous years, cryptophytes (Cryptophyceae) and occasionally diatoms dominated February phytoplankton samples in Lake Norman. The most abundant diatom during February 2009 was the pennate, Tabellaria fenestrata, one of the most common and abundant forms observed in Lake Norman samples since monitoring began in 1987.
In May, diatoms once again dominated samples at all locations. The most abundant diatom at Locations 2.0, 5.0, and 9.5 was the centrate, Cyclotella stelligera. At Locations 11.0 and 3-6
15.9, the pennate diatom, Fragilaria crotonensis was the most abundant species. Diatoms have typically been the predominant forms in May of previous years; however, cryptophytes were dominant in May 2008 and often dominated May samples from 1988 - 1995 (Duke Power Company 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997; Duke Power 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
During August 2009, green algae (Chlorophyceae) dominated densities at all locations (Table 3-5, Figures 3-7 through 3-11).
The most abundant green alga was the small desmid, Cosmarium asphearosporum var. strigosum (Table 3-7). Prior to 1999, green algae, with blue-green algae (Myxophyceae) as occasional dominants or co-dominants, were the primary constituents of summer phytoplankton assemblages, and the predominant green alga was also C. asphearosporum var. strigosum (Duke Power Company 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997; Duke Power 1998, 1999). During August periods of 1999 through 2001, Lake Norman summer phytoplankton assemblages were dominated by diatoms, primarily the small pennate, Anomoeoneis vitrea (Duke Power 2000, 2001, 2002). A. vitrea has been described as typically periphytic and widely distributed in freshwater habitats, and it was identified as a major contributor to periphyton communities on natural substrates during studies conducted from 1974 through 1977 (Derwort 1982). The possible causes of this significant shift in summer taxonomic composition were discussed in earlier reports and included deeper light penetration (the three deepest lake-wide Secchi depths were recorded from 1999 through 2001), extended periods of low water due to drawdown, and shifts in nutrient inputs and concentrations (Duke Power 2000, 2001, 2002). Whatever the cause, the phenomenon was lake-wide and not localized near MNS or Marshall Steam Station (MSS),
therefore, it was most likely due to a combination of environmental factors, and not station operations. Since 2002, taxonomic composition during the summer has shifted back to green algae predominance (Duke Power 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
During November 2009, densities at all locations were once again dominated by diatoms and the most abundant species was again T. fenestrata (Table 3-5; Figures 3-7 through 3-11). As is the case with May, diatoms have typically been dominant during past November periods, with occasional dominance by cryptophytes (Duke Power Company 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997; Duke Power 1998, 1999, 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Blue-green algae, which are often implicated in nuisance blooms, were never abundant in 2009 samples. Their overall contribution to phytoplankton densities was slightly higher than 3-7
in 2008; however, densities seldom exceeded 2% of totals (Duke Energy 2009). Prior to 1991, blue-green algae were often dominant at uplake locations during the summer (Duke Power Company 1988, 1989, 1990, 1991, 1992).
FUTURE STUDIES No changes are planned for the phytoplankton portion of the Lake Norman Maintenance Monitoring Program.
SUMMARY
Lake Norman continues to be classified as oligo-mesotrophic based on long-term, annual mean chlorophyll concentrations.
Chlorophyll a concentrations during 2009 were within historical ranges. Lake-wide mean chlorophyll a decreased from February through May then increased through August to the annual maximum. Overall chlorophyll a concentrations declined through November to the annual minimum. Some spatial variability was observed in 2009; however, maximum chlorophyll a concentrations were most often observed uplake at Locations 15.9 (May, November) and 69.0 (February, August), while minimum chlorophyll a concentrations were typically recorded from downlake at Locations 2.0, 5.0 and 8.0. The highest chlorophyll a value recorded in 2009, 13.24 tg/L, was well below the NC State water quality standard of 40 gtg/L.
Most phytoplankton densities in February, May, and August 2009 were lower than in those months of 2008, while most biovolumes during those months were higher than during the previous year. This disparity was due to taxonomic shifts from taxa with lower individual biovolumes to those with higher biovolumes. Standing crop values in November 2009 were lower than during November of 2008. Phytoplankton densities and biovolumes during 2009 never exceeded the NC guideline for algae blooms of 10,000 units/mL density and 5,000 mm3/m3 biovolume. Standing crop values in excess of bloom guidelines have been recorded during eight previous years of the Program.
As in past years, standing crop spatial distribution typically mirrored that of chlorophyll a, with high values usually observed at uplake locations, while comparatively low values were noted downlake.
3-8
Seston dry and ash-free weights were higher in February and May 2009 than in February and May 2008, while the opposite was the case in August and November. Downlake to uplake differences were observed to an extent during all quarters; however, a clear pattern of continually increasing values from downlake to uplake was not as apparent in February and November as in the other two sampling periods. Maximum dry and ash-free weights were generally observed at Location 69.0. Minimum values were most often noted at Locations 2.0 through 9.5.
Secchi depths often reflected suspended solids, with shallow depths loosely related to high dry weights. The lake-wide mean Secchi depth in 2009 was slightly lower than in 2008 and was within historical ranges of lake-wide mean Secchi depths recorded since 1992.
Diversity or the number of taxa of phytoplankton in 2009 was the highest yet recorded. The taxonomic compositions of phytoplankton communities during 2009 were similar to those of most previous years with the exception that diatoms rather than cryptophytes were dominant in February. Diatoms were dominant during all but August, when green algae dominated phytoplankton assemblages. Blue-green algae were slightly more abundant during 2009 than during 2008; however, their contribution to total densities seldom exceeded 2%.
The most abundant alga, on an annual basis, was the diatom, T. fenestrata which was the most important species during May and November at all locations.
The most abundant diatoms in May were C. stelligera and F. crotonensis.
The small desmid, C.
asphearosporum var. strigosum, was dominant in August 2009. All of these taxa have been common and abundant throughout the Lake Norman Maintenance Monitoring Program.
Lake Norman continues to support highly variable and diverse phytoplankton communities.
No obvious short-term or long-term impacts of station operations were observed.
3-9
Table 3-1.
Mean chlorophyll a concentrations (gtg/L) in depths (m) observed in Lake Norman in 2009.
composite samples and Secchi Chlorophyll a Feb May Aug Nov Location 2.0 4.38 2.24 4.95 2.10 5.0 5.13 2.07 5.17 2.35 8.0 6.21 2.60 4.02 3.05 9.5 5.31 2.68 5.14 3.55 11.0 4.67 3.42 5.83 3.47 13.0 6.34 5.18 5.43 3.44 15.9 7.24 6.11 9.55 4.43 69.0 9.20 5.14 13.24 1.53 Secchi depths Feb May Aug Nov Location 2.0 2.00 2.20 2.90 2.00 5.0 2.00 2.10 2.40 1.82 8.0 2.10 2.80 1.71 2.26 9.5 2.10 2.70 2.70 2.44 11.0 1.90 2.20 2.35 2.48 13.0 1.50 1.50 1.25 1.50 15.9 1.60 2.10 2.80 1.63 69.0 1.40 1.30 1.10 1.26 Annual mean from all Locations: 2009 2.05 Annual mean from all Locations: 2008 2.09 3-10
Table 3-2. Mean phytoplankton densities (units/mL) and biovolumes (mm 3/m3) by location and sample month from samples collected in Lake Norman during 2009.
Density Locations Month 2.0 5.0 9.5 11.0 15.9 Mean Feb 1,789 2,045 2,166 1,919 2,715 2,126 May 536 536 700 1,089 1,949 962 Aug 2,472 2,573 2,946 3,369 4,570 3,186 Nov 1,467 1,496 1,764 1,735 2,025 1,697 Biovolume Locations Month 2.0 5.0 9.5 11.0 15.9 Mean Feb 2,235 2,846 3,243 2,064 3,460 2,770 May 294 326 369 843 1,199 606 Aug 1,869 1,741 2,473 2,793 3,855 2,546 Nov 1,406 1,570 2,019 2,025 2,839 1,972 Table 3-3. Total mean seston dry and ash free-dry weights (mg/L) from samples collected in Lake Norman during 2009.
Dry weights Locations Month 2.0 5.0 8.0 9.5 11.0 13.0 15.9 69.0 Mean Feb 3.19 2.56 2.21 2.03 1.84 2.06 1.93 3.76 2.45 May 1.62 1.48 1.09 1.23 1.62 1.83 2.27 4.40 1.94 Aug 1.36 1.61 1.33 1.48 1.83 1.56 1.95 6.25 2.17 Nov 1.05 1.30 0.98 1.57 1.28 1.20 0.92 1.96 1.28 Ash-free dry weights Month Feb 1.38 0.93 0.85 0.83 0.83 0.76 0.93 1.10 0.95 May 0.75 0.62 0.61 0.61 0.87 1.08 1.10 1.19 0.85 Aug 0.83 0.95 0.93 1.00 1.20 0.81 1.28 2.53 1.19 Nov 0.57 0.58 0.46 0.69 0.59 0.55 0.32 0.35 0.51 3-11
Table 3-4. Phytoplankton taxa identified in quarterly samples collected in Lake Norman each year from 1994 to 2009.
Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Class: Chlorophyceae Acanthosphaera zachariasi Lemm.'
Actidesmium hookeri Reinscha Actinastrum hantzchii Lagerheim X
X Ankistrodesmus braunji (Naegeli) Brunn X
X X
X X
X X
X X
X X
X X
X X
A. convolutus Corda X
A. falcatus (Corda) Ralfs X
X X
X X
X X
X X
X X
X X
X X
X A. fusiformis Corda sensu Korsch.
X A. nannoselene Skuja x
A. spiralis (Turner) Lemm.
X A. spp. Cordas Arthrodesmus convergens Ehrenberg X
X X
X X
X X
A. incus (Breb.) Hassall X
X X
X X
X X
X X
X X
A. incus v ralisii W. West X
A. octocornis Ehrenberg X
X X
X X
X X
A. ralfsii W. West X
X X
X A. subulatus Kutzing X
X X
-X X
X X
X X
X X
X X
A. validus v. increassalatus Scott & Gron.
X A. spp. Ehrenberg X
Asterococcus limneticus G. M. Smith X
X X
X X
X X
X A. superbus (Cienk.) Scherffel X
X Botryococcus braunii Kutzinga Carteriafritzschii Takeda X
X X
X X
X X
X C. globosa Korsch X
X X
X C. spp. Diesing X
X Characium ambiguum Hermann X
C. limneticum Lemmerman X
C. spp. Braun a Chlarydomonas spp. Ehrenber X
X X
X X
X X
X X
X X
X X
X X
X Chlorella vulgaris Beyerink X
X X
X Chlorogonium euchlorum Ehrenberg X
X X
X X X
X X
X C. spirale Scherffel & Pascher X
X X
X X
X X
X Closteriopsis longissima W. & West X
X X
X X
X X
X X
X X
X X
X X
X Closterium acutum Breb.
X X
X C. comu Ehrenberg X
X C. gracile Brebisson X
X C. incurvum Brebisson X
X X
X X
X X
X X
X X
X X
X X
X C. parvulum Nageli X
C. tumidum Johnson x
" spp. Nitzscha Coccomonas orbicularis Stein X
X X
X X
X X
X Coelastrum cambricum Archer X
X X
X X
X X
X X
X X
X X
X X
X C. microporum Nageli X
X X
x X
X X X
X X
C. proboscideum Bohlin X
" reticulatum (Dang.) Sinn.
X XXX C sphaericum Nageli X
X X
X X
X X
X X
X X
C. spp. Nageli a 3-12
Table 3-4. (Continued).
Page 2 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Cosmarium angulosum v. concin. (Rab) W&W X
X X
X X
C. asphaerosporum v. strigosum Nord.
X X
X X
X X
X X
X X
X X
X X
X X
C. contractum Kirchner X
X X
X X
X X
X X
X X
X X
X X
X C. moniliforme (Turp.) Ralfs x
X X
X X X
X C. notabile Brebisson X
C. phaseolus f. minor Boldt.
X X
X X
X X
X X
C. pokornyanum (Grun.) W. & G.S. West X
X X
X C. polygonum (Nag.) Archer X
X X
X X
X X
X X
X X
X X
X X
C portianum Archer I x C raciborskii Lagerheim X
X X
X X
C. regnelifi Wille X
X X
X X
X X
X X
X X
X X
X C. regnesi Schmidle X
C. regnesi v. montana Schmidle X
C. subreniforme Nordstedt X
X X
c subprotumidum Nordst.
X
. tenue Archer X
X X
X X
X X
X X
X X
X X
X X
C. tinctum Ralfs X
X X
X X
X X
X X
X X
X X
X X
X C. tinctum v. subretusum Messik.
I X
C. tinctum v. tumidum Borge.
X X
X X
X X
X X
X X
X X
C. trilobatum v. depressum Printz X
C tumidum Borge X
C spp. Corda X----
Crucigenia apiculata (Lemm.) Schmidl X
7 X
x C. crucifera (Wolle) Collins X
X X
X X
X X
X X
X X
X X
X X
C. fenestrata Schmidle X
X X
X X
X X
X
" irregularis Wille X
X X
X X
X X
X X
X X
C quadrata Morren X
X X
". rectangularis (A. Braun) Gay X
X X
C. tetrapedia (Kirch.) West & West X
7 X
X X x x
x x
X X
X x x
x x
Dictyospaerium ehrenbergianum Nageli X
X X
X X
X X
X X
D. pulchellum Wood X
X X
X X
7 X X
x X
X X x X
X X
Dimorphococcus spp. Brauna Elakatothrix gelatinosa Wille x
7 X
X X x x
x x
X X
X x x
x x
Errerella bornheimiensis Conrad X
X X
X X
X Euastrum ansatum v. dideltiforme Ducel.
X--
E. banal (Turp.) Ehrenberg x
E. denticulatum (Kirch.) Gay X
X X
X I X
x x
X X
X x
x X
X E. elegans Kutzing X
E. turneri West I-X E spp. Ehrenberg-X Eudorina elegans Ehrenberg X
x X
x X7 x
Franceia droescheri (Lemm.) G. M. Sm.
x 7 X
X X
X X
X x X X
X X 7 X
X F. ovalis (France) Lemm.
x7X 7
X X
X x X
X x
F. tuberculata G. M. Smith X
Gloeocystis botryoides (Kutz.) Nageli I-X x
7 x
x G. gigas KutzingI X
X X
7 X X
x X
X X X X
X X
3-13
Table 3-4. (Continued).
Page 3 of 12 Years Taxon 94 95 96 97 98 99 0
01 02 03 04 05 06 07 08 09 G. major Gemeck ex. Lemmermann X
X G. planktonica (West & West) Lemm.
X X
X X
X X
X X
X X
X X
X X
X X
G. vesciculosa Naegeli X
X X X
X X
X X
X G. spp. Nageli X
Golenkinia paucispina West & West X
X X
X X
X X
X G. radiata Chodat X
X X
X X
X X
X X
X X
X X
X X
X Gonium pectorale Mueller X
X X
X X
X X
G. sociale (Duj.) Warming X
X X
X X
X X
X X
X X
Kirchneriella contorta (Schmidle) Bohlin X
X X
X X
X K elongata G.M. Smith X
I X
X I Xx K lunaris (Kirch.) Mobius I
X x X
K lunaris v. dianae Bohlin X
X X
X X
X X
X X
X K lunaris v. irregularis G.M. Smith X
X X
K obesa W. West X
X XX K subsolitaria G. S. West X
X X
X X
X X
X X
X X
X X
X K spp. Schmidle I X X
X X
X X
Lagerheimia ciliata (Lagerheim) Chodat I
X X
L. citriformis (Snow) G. M. Smith X
I X
X X
X L. longiseta (Lemmermann) Printz I
X X
X X x L. longiseta v. major G. M. Smith I
X L. quadriseta (Lemm.) G. M. Smitha L. subsala Lemmerman X
X X
X X
X X
X X
X X
X X
Mesostigma viride Lauterborne X
X X
X X
X X
X X
X X
X X
X Micractinium pusillum Fresen.
X X
X X
X X
X X
X X
X X
X X
X X
Monoraphidium contortum Thuret X
M pusillum Printz X
Mougeitia elegantula Whittrock X
X X
X X
X X
X X
X X
X X
X X
M spp. Agardh X
X Nephrocytium agardhianum Nageli X
X X
X X
X X
X N. eeaysiscepanum W. West X
N. limneticum (G.M. Smith) G.M. Smith X
X X
X X
X N. obesum West & West IXI Oocystis borgii Snow X
X X
X X
X X
XX
- 0. eillyptica W. West X
I X
X xX
- 0. lacustris Chodat X
X X
X
- 0. parva West & West X
X X
X X
X X
X X
X X
X X
X X
- 0. pusilla Hansgirg X
X X
X X
X X
X X
X X
X X
X X
X
- 0. pyriformis Prescott X
X
- 0. solitaria Wittrock I
IX
- 0. submarina Lagerheim X
X
- 0. spp. Nagelia Pandorina charkowiensis Kprshikov X
X X
P. morum Bory X
X X
X X
Pediastrum biradiatum Meyen X
X X
X P. duplex Meyen X
X X
X X
XX X
X X
X X
X X
P. duplex v. clatheatum (A. Braun) Lag.
X X
P. duplex v. gracillimum West and West X
X X X X
X X
X X
P. duplex v. reticulatum Lagerheim X
3-14
Table 3-4. (Continued).
Page 4 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 P. tetras v. tetroadon (Corda) Rabenhorst X
X X
X X
X X
X X
X X
X X
X X
X P. spp. Meyen a Phacotus angustus Lemmermann X
Planktosphaeria gelatinosa G. M. Smith X
X X
X X
X X
Quadrigula closterioides (Bohlin) Printz X
X X
X X
X X
X X
X Q. lacustris (Chodat) G. M. Smith X X X
X X
X X
X Scenedesmus abundans (Kirchner) Chodat X
X X
X X
S. abundans v. asymetrica (Schr.) G. Sm.
X X
X X
X X
X X
X S. abundans v. brevicauda G. M. Smith X
X X
X X
X S. abundans v. longicauda G.M. Smith X
X S. acuminatus (Lagerheim) Chodat X
X X
X X
X X
X X
X X
X X
X X
S. arcuatus Lemmermann X
S. arcuatus v. platydisca G. M. Smith X
S. armatus (Chod.) G. M. Smith X
S. armatus v. bicaudatus (Gug.-Pr..)Chod X
X X
X X
X X
X X
X X
X X
X X
X S. byuga (Turp.) Lagerheim X
X X
X X
X X
X X
X X
X X
X X
X S. byuga v. alterans (Reinsch) Hansg.
X X
X S. brasiliensis Bohlin X
X X
X X
X X
X X
X X
X X
X X
S. denticulatus Lagerheim X
X X
X X
X X
X X
X X
X X
X X
S. denticulatus v. recurvatus Schumacher X
X X
X X
X X
S. dimorphus (Turp.) Kutzing X
X X
X X
X X
X X
X X
X X
S. incrassulatus G. M. Smith X
S. opoliensis P. Richter X
X X S. parisiensis Chodat X
X S. quadricauda (Turp.) Brebisson X
X X
X X
X X
X X
X X
X X
X X
S. smithii Teiling X
X X
X X
X S. serratus (Corda) Bohlin X
S. spp. Meyen X
Schizochlamys compacta Prescott X
X X
X X
X X
X X
S. gelatinosa A. Braun X
x X
X X
X X
X Schoederia setigera (Schroed.) Lemm.
X X
Selenastrum bibraianum Reinsch X
X X
S. gracile Reinsch X
X X
X X
S. minutum (Nageli) Collins X X X
X X
X X
X X
X X
X X
X X
X S. westii G. M. Smith X
X X
X X
X X
X X
X X
X Sorastrum americanum (Bohlin) Schm.
X X
S. spinulosum Nageli X
Sphaerocystis schoeteri Chodat X
X X
X X
X X
X X
X X
Sphaerozosma granulatum Roy & BI. a Stauastrum americanum (W&W) G. Sm.
X X
X X
X X
X X
X X
X X
X X
X S. apiculatum Brebisson X
X X
X X
X X
X X
X X
X X
S. aspinosum v. annulatum W.& G.S.Wst.
X S. brachiatum Ralfs X
X X
X X
X X
X X
X X
& brevispinum Brebisson X
S. chaetocerus (Schoed.) G. M. Smith X
S. capitulum Brebisson X
S. curvatum W. West X
X X
X X
X XIX X X
X X
X X
X X
3-15
Table 3-4. (Continued).
Page 5 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 S. curvatum v. elongatum G.M. Smith X
X S. cuspidatum Brebisson X
X X
X X
X X
X X
X X
X X
S. dejectum Brebisson X
x X
X X
S. dickeii v. maximum West & West X
S. dickeii v. rhomboidium W.& G.S. West X
X S. gladiosum Turnera S. leptocladum Nordstedt X
S. leptocladum v. sinuatum Wolle a S. manfeldtui v.fluminense Schumacher X
X X
X X
X X
X X
X X
X X
S. megacanthum Lundell X
X X
X X S. ophiura v. cambricum (Lund) W. & W.
X X
X S. orbiculare Ralfs X
X S. paradoxum Meyen X
X X
X X
X X
X S. paradoxum v. cingulum W. & W.
x X
X X
X X
S. paradoxum v. parvum W. West X
X X
X X
X X
X X
S. pentacerum (Wolle) G. M. Smith X
X X
X X
S. subcruciatum Cook & Wille X
X X
X X
X X
X X
X X
X X
S. tetracerum Ralfs X
X X
X X
X X
X X
X X
X X
X X
X S. turgescens de Not.
X X
X S. vestitum Ralfs X
X X
X S. spp. Meyen X
Stichococcus scopulinus Hazen X
S. spp. Nageli X
Stigeoclonium spp. Kutzing X
X Tetraedron arthrodesmiforme (W.) Wol.
x X
X X
X Tetraedron asymmetricum Prescott X
T. bifurcatum (Wille) Lagerheim X
T. bifurcatum v. minor Prescott X
T. caudatum (Corda) Hansgirg X
X X
X X
X X
X X
X X
X X
X X
T. caudatum v. longispinum x
T. limneticum Borge X
T lobulatum (Naegeli) Hansgirg X
X T. lobulatum v. crassum Prescott X
X T. minmum (Braun) Hansgirg X
X X
X X
XX X
X X
X X
X X
X T. muticum (Braun) Hansgirg X
X X
X X
X T. obesum (W & W) Wille ex Brunnthaler X
X X
T. pentaedricum West & West X
X X
X T planktonicum G. M. Smith X
X X
X X
X X
X X
X T regulare Kutzing X
X T. regulare v. bifurcatum Wille X
T. regulare v. incus Teiling X
T trigonum (Nageli) Hansgirg X
X X
X X
X X
X X
X X
X X
T. trigonum v. gracile (Reinsch) DeToni X
X X
X X
T. spp. Kutzinga Tetrallantos lagerheimui Teiling X
X X
X Tetraspora lamellose Prescott X
T. spp. Link X
3-16
Table 3-4. (Continued).
Page 6 of 12 Years TAXON 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Tetrastrum heteracanthum (Nor.) Chod.
X X
X X
T. staurogeniforme (Schroeder) Lemm.
X X
Tomaculum catenatum Whitford X
Treubaria setigerum (Archer) G. M. Sm.
X X
X X
X X
X X
X X
X X
X X
X X
Westella botryoides (W. & W.) Wilde.
X X
X X
X X
X W. linearis G. M. Smith X
X X
X X
X Xanthidium antiloparium. v. floridense Sc. & Gron.
X X cristatatum v. uncinatum Breb.
X X
X X
X X
X X spp. Ehrenberg X
X Class: Bacillariophyceae Achnanthes lanceolata Brebisson X
X A. microcephala Kutzing X
X X
X X
X X
X X
X X
X X
X X
A. spp. Bory X
X X
Amphiprora ornate Bailey X
Amphora ovalis Kutzing X
Anomoeoneis vitrea (Grunow) Ross X
X X
X X
X X
X X
X X
X X
X X
A. spp. Pfitzer X
Asterionellaformosa Hassall X
X X
X X
X X
X X
X X
X X
X X
Attheya zachariasi J. Brun X
X X
X X
X X
X X
X X
X X
X X
X Cocconeis placentula Ehrenberg X
X X
X X
C. spp. Ehrenberg X
I Cyclotella comta (Ehrenberg) Kutzing X
X X
X X
X X
X X
X X
X X
X X
X C glomerata Bachmann X
X X
X X
X X
X X
X X
X
. meneghiniana Kutzing X
X X
X X
X X
X X
X X
X X
X X
C. pseudostelligera Hustedt a C. stelligera Cleve & Grunow X
X X
X X
X X
X X
X X
X X
X X
X C. spp. Kutzinga Cymbella affinis Kutzing X
X C. gracilis (Rabenhorst) Cleve X
X C. minuta (Bliesch & Rabn.) Reim.
X X
X X
X X
X X
X X
X X
C. naviculiformis Auersw. ex Heib.
X C. tumida (Brebison) van Huerck X
X C. turgida (Gregory) Cleve X
C. spp. Agardh a Denticula elegans Kutzing X
X x
x D. elegans v. crassa (Naegeli) Hustedt X
D. thermalis Kutzing X
x__
x Diploneis ellyptica (Kutzing) Cleve X
D. marginestriata Hustedt X
D. ovalis (Hilse) Cleve X
D. puella (Schum.) Cleve x
x D. spp. Ehrenberga Eunotia flexuosa v. eurycephala Grun.
X E. zasuminensis (Cab.) Koemer X
X X
X X
X X
X X
X X
X X
X X
Fragilaria crotonensis Kitton X
X X
X X
X X
X X
X X
X X
X X
X F. construens (Ehrenberg) Grunow X
Frustulia rhomboides (Ehr.) de Toni X
3-17
Table 3-4. (Continued).
Page 7 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 F rhomboides v. saxonica (Rabh.) de T.
X Gomphonema angustatum (Kutz.) Rabh.
X G. gracile (Her.) Van Huerk X
X G. parvulum Kutz.
X X
X X
G. spp. Agardh X
Melosira ambigua (Grunow) O. Muller X
X X
X X
X X
X X
X X
X X
X X
X M distans (Ehrenberg) Kutzing X
X X
X X
X X
X X
X X
X X
X X
X M granulata (Ehrenberg) Ralfs X
x X
M granulata v. angustissima 0. Muller X
X X
X X
X X
X X
X X
X X
X X
X M italica (Ehrenberg) Kutzing a M italica v. tennuissima (Grin.) 0. Mull.
X X
M varians Agardh X
X X
X X
X M spp. Agardh X
X X
X X
X X
X X
X X
x Meridion circulare Agardh X
Navicula cryptocephala Kutzing X
X x
X N. exigua (Gregory) O. Muller X
X X
N. exigua v. capitata Patrick X
X N. radiosa Kutzing X--
X N. radiosa v. tenella (Breb.) Grun.
X X
X X
X N. subtilissima Cleve X
X X
X X
X X
N. spp. Bory X
X X
Nitzschia acicularis W. Smith X
X X
X X
X X
X X
X X
X X
X N. agnita Hustedt X
7 X
X X x X
X X
X X
X x X
X X
N. communis Rabenhorst X
N. holsatica Hustedt X
X X
X X
X X
X X
X X X
X X
N. kutzingiana Hilse X
X X
X X
N. linearis W. Smith X
X X
N. palea (Kutzing) W. Smith x
7 X
X X
X 7 x x
X X
X N. sublinearis Hustedt X
X X
X X
N. thermalis Kutzing-X N. spp. Hassall X
X x
X Pinnularia biceps Gregory X
P. mesolepta (Her.) W. Smith X
P. spp. Ehrenberg X
X X
Rhizosolenia spp. Ehrenberg X
X X
X X X X
X X
X X X
X X
X X
Skeletonema potemos (Weber) Hilse X
X X
X X
X X
X x
X x
x Stephanodiscus astraea (Her.) Grunow X
x x
S. spp. Ehrenberg X
7 X
X X
x X
X x
x X
Surirella angustata Kutz.
X S. linearis v. constricta (Her.) Gro.
X X
X S. tenuis Mayer X
Synedra actinastroides Lemmerman X
S. acusKutzing X
X X
X X
X X
X X
X X
S. amphicephala Kutzing X
X S. delicatissima Lewis X
S. filiformis v. exilis Cleve-Euler X
X X
X X
X X
X X
X X
S. planktonica Ehrenberg X
7 X
X X
X X X
X X
X X
X X
X X
S. rumpensKutzing 7
X X
X 7
7 X
X X
7 X
X X
x X
3-18
Table 3-4. (Continued).
Page 8 of 12 Years Taxon 94 95 96 97 98 99 0
01 02 03 04 05 06 07 08 09 S. rumpens v.fragilarioides Grunow a S. rumpens v. scotica Grunow x
S. ulna (Nitzsch) Ehrenberg x
x x
x X
X x
x X
X X
X X
X S. spp. Ehrenberg X
Tabellariafenestrata (Lyngb) Kutzing X
X X
X X
X X
X X
X X
X X
X X
X T flocculosa (Roth.) Kutzing*
X X
X X X Class: Chrysophyceae Aulomonas purdyii Lackey X
X X
X X
X X
X X
X X
X X
X Bicoeca petiolatum (Stien) Pringsheim X
X Calycomonas pascheri (Van Goor) Lund X
x Centritractus belanophorus Lemm.
X Chromulina nebulosa Pascher x
x x
C. spp. Chien.
X X
X X
X X
X Chrysococcus rufescens Klebs x
Chrysosphaerella solitaria Lauterb.
X 7
x x
x X X
x x
x X X
X X
X X
Codomonas annulata Lackey X
X X
X X
X X
X X
X X
X X
Dinobryon acuminatum Ruttner I
x D. bavaricum Imhof X
7 X
X X X X
X x x
X X
X X
X X
D. cylindricum Imhof X
X X
X x
X X
X X
X D. divergens Imhof X
X X
X X
X X
X X
X X
X D. pediforme (Lemm.) Syein.
X x
D. sertularia Ehrenberg X
7 X
7 7
X XXX D. sociale Ehrenberg I
x D. spp. Ehrenberg X
7 X
X X X
X X
X X x
x X
X X
Domatomococcus cylindricum Lackey X
X X
X Erkinia subaeguicilliata Skuja X
7 X x x
X X
X x x
x X
x X
x x
Kephyrion campanuliforme Conrad X
K littorale Lund X
X X
X X
X X
X X
K petasatum Conrad x
K rubi-claustri Conrad X
x X
X X
X X
X K skujae Ettl a K valkanovii Conrad X x K. spp. Pascher X
X X
X X X
X X
X X X
X X
X X
Mallomonas acaroides Perty X
X x
X X
M akrokomos (Naumann) Krieger X
X x
x X
x x
x X
M allantoides Perty x
x M allorgii (Deft.) Conrad x
M alpina Pascher X
X M caudata Conrad X
X X
X7 x X
7 7 X M. globosa Schiller X
x x
x x
x x
R x
x x
M. producta Iwanoff x
x x
X X
X X
M pseudocoronata Prescott X
7 x
x x X X
x x
x x X
X X
X X
M tonsurata Teiling X
X X
X X
X X
X X
X X
X X
X X
X M spp. Perty X
X X
Ochromonas granularis Doflein X
X X
X X
X X I X
X X
X
- 0. mutabilis Klebs X
X7
- 0.
spp. Wyss X7 X
X X 7 X X
X X 777777 3-19
Table 3-4. (Continued).
Page 9 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Pseudokephyrion concinum (Schill.) Sch.
X X
P. schilleri Conrad X
X X
X X
X X
P. tintinabulum Conrad X
P. spp. Pascher X
X X
X Rhizochrisis polymorpha Naumann X
X X
X X
X X
X X
X X
R. spp. Pascher X
Salpingoecafreguentissima (Zach.) Lem.
X X
X X
X Stelexomonas dichotoma Lackey X
X X
X X
X X
X X
X X
X X
Stokesiella epipyxis Pascher X
X X
X X
X Synura sphagnicola Korschikov X
S. spinosa Korschikov X
X X
X X
X X
X X
X X
X X
X X
S. uvella Ehrenberg X
X X
X X
S. spp. Ehrenberg X
Uroglenopsis americana (Caulk.) Lemm.
X X
X X
Class: Haptophyceae Chrysochromulina parva Lackey X
X X
X X
X X
X X
X X
X X
X X
X Class: Xanthophyceae Characiopsis acuta Pascher X
X X
X X
X C. cylindrica (Lambert) Lemm.
X X C. dubia Pascher X
X X
X X
X X
X X
X X
X X
X Dichotomococcus curvata Korschikov a Ophiocytium capitatum v. longisp. (M) L.
X X
X X
X X
X X
Stipitococcus vas Pascher X
Class: Cryptophyceae Cryptomonas erosa Ehrenberg X
X X
X X
X X
X X
X X
X X
X X
X C. erosa v. reflexa Marsson X
X X
X X
X X
X X
X X
X
" gracilia Skuja X
C marsonii Skuja X
X X
X X
C. obovata Skuja X
X X
X X
C. ovata Ehrenberg X X X
X X
X X
X X
X X
X X
X X
X C. phaseolus Skuja X
C reflexa Skuja XX X
X X
X X
X X
X X
X X
X X
X C spp. Ehrenberg X
X X
Rhodomonas minuta Skuja X
X X
X X
X X
X X
X X
X X
X X
X Class: Myxophyceae Agmenellum quadriduplicatum Brebisson X
X X
X X
X X
X X
X X
X X
X X
A. thermale Drouet and Daily X
X Anabaena catenula (Kutzing) Born.
X X
X Anabaena circinalis (Kutz.) Rabenhorst X
A. inaequalis (Kutzing) Born.
X x
X A. scheremetievi Elenkin X
X X
X X X X
A. wisconsinense Prescott X
X X
X X
X X
X X
X X
X X
X X
A. spp. Bory X
X X
XX X
X X
XX Anacystis incerta (Lemm.) Druet & Daily X
X -
X X
I 3-20
Table 3-4. (Continued).
Page 10 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 A. spp. Meneghini a Aphanocaspsa rivularis (Carm.) Raben.
X Chroococcus dispersus (Keissl.) Lemm.
X XX X X C. giganteous W. West X
C. limneticus Lemmermann X
X X
X X
X X
X X
X X
X C. minor Kutzing X
X X
X XX X
C. turgidus (Kutz.) Lemmermarma
". spp. Nageli X
x x
x x x X
X X
x x
x X X
X X
Coelosphaerium kuetzingiana Nag~elia C. neagleanum Unger X X Dactylococcopsis irregularis Hansgirg X
X X
X X
-X D. musicola Hustedt X
D. raphidiopsis Hansgirg X
D. rupestris Hansgirg X
D. smithii Chodat and Chodat X
X X
X X
X X
X X
D. spp. Hansgirg X
Gomphospaeria lacustris Chodat X
X Lyngbya contorta Lemmermanna L. limnetica Lemmermann X
L. ochracea (Kutzing) Thuret X
X X
X X
L. subtilis W. West X
L. tenue Agardh X
X X
L. spp. Agardh X
X X
X X
X X
X X
X X
X X
X Merismopedia tenuissima Lemmermann X
Microcystis aeruginosa Kutzing X
X X
X X
X X
X X
X X
X X
Oscillatoria amoena (Kutz.) Gomont X
- 0. amphibia Agardh X
X X
X X
- 0. geminata Meneghini X
X X
X X
X X
X X
X X
X X
X X
- 0. limnetica Lemmermann X
X X
X X
X X
X X
X X
X X
X X
- 0. splendida Greville X
X X
X
- 0. subtilissima Kutz.
X X
X X
X X
X X
X X
O. spp. Vaucher X
X x
X x
Phormidium angustissimum West & West X
P. spp. Kutzing X
Raphidiopsis curvata Fritsch & Rich X
X X
X X
X X
X X
X X
R. mediterranea Skuja X
R. spp. Fritsch & Rich X
Rhabdoderma sigmoidea Schm. & Laut.a Spirulina subsala Oersted X
X X
Synecococcus lineare (Sch. & Lt.) Kom.
X X
X X
X X
X X
X Class: Euglenophyceae Euglena acus Ehrenberg X
X X
X E. deses Ehrenberg X X X
E. fusca (KIebs). Lemmermann X
E. minuta Prescott X
X X
X X
X X
E. polymorpha Dangeard X
X X
X X
X X
E. proxima Dangeard -
X X
X X
3-21
Table 3-4. (Continued).
Page I11 of 12 Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 E. texia (Duj.) Hubn.
X E. spp. Ehrenberg X
X X
X X
X X
X X
X X
X Lepocinclus acicularis France X
L. acuta Prescott X
X L. fusiformis Lemmermann X
L. glabra Drezepolski X
L. ovum. (Ehr.) Lemm.
x X
X X Xx L. ovum. v. palatina Lemmermann L. sphagnophila Lemmermann X
L. spp. Perty X
Phacus acuminatus Stokes X
P. cuvicauda Swirenko X
P. longicauda (Her.) Dujardin X
X P. orbicularis Hubner X
X P. tortus (Lemm.) Skvortzowa P. triguter Playfair X
P. spp. Dujardin a Trachelomonas abrupta (Swir.) Deflandre X
T. abrupta v. minor Deflan.
X X
T. acanthostoma (Stk.) Deft.
X X
X X
X X
X T. ensifera Daday X
X T. euchlora (Ehrenberg) Lemmermann x
T hispida (Perty) Stein X
X X
X X
X X
X X
X T. lemmermanii v. acuminata Deflandre X
X T. pulcherrima Playfair X
T. pulcherrima v. minor Playfair X
T. varians (Lemm.) Deflandre X
T. volvocina Ehrenberg x
X X
X X
X X X X
T. spp. Ehrenberg X
Class: Dinophyceae Ceratium hirundinella (OFM) Schrank X
X X
X X
X X
C hirundinella v. brachyceras (Day.) Est.
x x
x Glenodinium borgei (Lemm.) Schiller X
X X
G. gymnodinium Penard X
X X
X X
G. palustre (Lemm.) Schiller X
G. penardiforme (Linde.) Schiller X X X
X X
X X
G. quadridens (Stein) Schiller X
X X G. spp. (Ehrenberg) Stein X
Gymnodinium aeruginosum Stein X
X X
X X
X X
X G. neglectum (Schilling) Lindemann X
G. spp. (Stein) Kofoid & Swezy X
X X
X X
X X
X X
X X
X X
Peridinium aciculiferum Lemmermann X
P. cinctum (Muller) Ehrenberg x
X P. godlewskii Wolzynska I
x P. inconspicuum Lemmermann X
X X
X X
X X
X X
X X
X X
X X
X P. intermedium Playfair X
X X
X X
X X
X X
X X
X P. limbatum (Stokes) Lemm.
X X
X 3-22
Table 3-4. (Continued).
Years Taxon 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 P. pusillum (Lenard) Lemmermann X
X X
X X
X X
X X
X X
X X
X X
P. quadridens Stein X
P. umbonatum Stein X
P. willei Huitfeld-Kass X
X X
X X
P. wisconsinense Eddy X
X X
X X
X X
X X
X X
X X
X X
X P. spp. Ehrenberg X
X Class: Chloromonadophyceae Gonyostomum depresseum Lauterbome X
X X
X X
X X
X X
X X
G. semen (Ehrenberg) Diesing X
G. spp. Diesing X
a= taxa found during 1987 - 93 only.
3-23
Table 3-5. Dominant classes, their most abundant species, and their percent composition (in parentheses) at Lake Norman locations during each sampling period of 2009.
Location February May 2.0 Bacillariophyceae (76.3)
Bacillariophyceae (66.0)
Tabellaria fenestrata (66.3)
Cyclote/la stelligera (30.9) 5.0 Bacillariophyceae (87.3)
Bacillariophyceae (71.1)
T.fenestrata (72.3)
C. stelligera (39.8) 9.5 Bacillariophyceae (89.9)
Bacillariophyceae (50.0)
T.fenestrata (80.5)
C. stelligera (35.0) 11.0 Bacillariophyceae (85.6)
Bacillariophyceae (60.4)
T.fenestrata (36.2)
Fragillaria crotonensis (21.2) 15.9 Bacillariophyceae (58.3)
Bacillariophyceae (69.5)
T.fenestrata (27.8)
F. crotonensis (40.0)
August November 2.0 Chlorophyceae (55.8)
Bacillariophyceae (45.4)
Cosmarnum asphearosporum variety Tabellania fenestrata (29.7) stngosum (30.0) 5.0 Chlorophyceae (55.0)
Bacillariophyceae (48.5)
C. asphear. var. strig. (28.3)
T. fenestrata (31.1) 9.5 Chlorophyceae (52.8)
Bacillariophyceae (52.3)
C. asphear. var. strig. (26.9)
T. fenestrata (39.9) 11.0 Chlorophyceae (46.6)
Bacillariophyceae (48.6)
C. asphear. var. strig. (26.4)
T. fenestrata (32.4) 15.9 Chlorophyceae (45.3)
Bacillariophyceae (53.4)
C. asphear. var. strig. (24.2)
T. fenestrata (24.8) 3-24
Chlorophyl a (pg/L)
Density (unds/mL) 14 12 10 8
6 4
2 0
/
//
i,
5,000 4,000 3,000 2,000 1,000 1f~
0 I
I I
I I
00 9
9 i
9 90)09 (N
kn M
M V
C)
)
MC C?
0 U) 0 C
(N LO (n
knU Seston Dry Weight (mgiL)
Biovolume (mm 3/rn3) 7 6
5 4
3 2
1 0
7 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1,000 500 0
0' 0,
(0 03 S) 9 CO-W4) 0)
(0 CD C2 In C2 M
(N 6f
- 0) 6 U
Locatons Feb May Aug Nov Figure 3-1.
Phytoplankton chlorophyll a, densities, biovolumes, and seston weights at locations in Lake Norman in February, May, August, and November 2009.
3-25
14 12 10 1-1 0t-o 8
6 4
2 0 4 I
I Feb May Aug Nov Maximum Minimum 2009
--- Mean I
Figure 3-2. Lake Norman phytoplankton chlorophyll a seasonal maximum and minimum lake-wide means since August 1987 compared with the long-term seasonal lake-wide means and lak-wide means for 2009.
3-26
C,)
30 25 20 15 10 5
0
20 Mixing Zone 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years 8 0
-- w-9.5 30
.5 I:a-2 C)
.5 a-C) 25 --------------------------
20 15 10 5
87 88 09 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years 11 -0
-- 4*- 13 -0 1
30 25 20 15 10 5
0 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years CL 2
C>
30 25 20 15 10 5
0 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years Figure 3-3.
Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman from February 1988 - 2009 (clear data points represent long-term maxima.
3-27
30 25 20 15 10 5
0 i-
-n
-Z n-5.0 Mixing Zone 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years 8.0
-. m-95 30 25 20 15 10 5
A AL I
IK v
\\6_ý -*-ý 0
30 25 20 15 10 5
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years
-'-110 13-0 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years
-'--15,9
-m--69.0 1
CL 2
30 25 20 15 10 5
9ý A I\\
IN I\\
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years Figure 3-4.
Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman from May 1988 - 2009 (clear data points represent long-term maxima).
3-28
2 30 25 20 15 10 5
0 2-0 50 Mixing Zone t~~77~77..
87 88 89 90 91 92 93 94 95 96 97 9e 99 00 01 02 03 04 05 06 07 08 09 Years 1
-8.0
--0-9-5 1-2 C,
30 25 20 15 10 5
0 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years 11.0 0a 0
Z.
(-3 30 25 20 15 10 5
0 Z
87 88 89 90 91 92 93 94 95 96 97 96 99 00 01 02 03 04 05 06 07 08 09 Years 1
159
--169.0
.5 a.
2a
(-3 35 30 25 20 15 10 5
0
-'V 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years Figure 3-5.
Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman during August 1987 - 2009 (Note: axis for 15.9 and 69.0, and that clear data points represent long-term maxima).
3-29
31 20 18 16 14 12 10 8
6 4
2 0
M l-i Z o--
- - - n e - --
.......................................................................................... 8-- - -- -- - ---- -------
ZE C3 20 18 16 14 12 10 8
6 4
2 0
I~ ~
~
~~-
0----'-95 67 68 89 90 91 92 93 94 95 96 97 90 99 00 01 02 03 04 05 06 07 0 09 Years S
11-0 130 2
20 18 16 14 12 10 8
6 4
2 0
I-87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years 1
- 15 9 690 1
(U a20 C) 20 18 16 14 12 10 8
6 4
2 0
/IR 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Years Figure 3-6.
Phytoplankton mean chlorophyll a concentrations by location for samples collected in Lake Norman during November 1987 - 2009 (Note: change in axis, and that clear data points represent long-term maxima).
3-30
3,500 3,000 I
- uuier
.-I2,500................
3 2,000 1,5 0 0 a) 0 1,000 500 1-Feb May Aug Nov 3,000----------------------------
~2,500 ----------------- ----------------------------------------------------------
4) 2,5 0 0
>.2 1,000 5 0 0 Feb May Aug Nov Figure 3-7.
Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 2.0 in Lake Norman during 2009.
3-31
3,500 -
3,000 E 2,500 -
- 2,000
.m 1,500 C
a, 1,000 500 0
-I
- Chlorophyceae OChrysophyceae
- Myxophyceae MOther E3 Baciftriophyceae
" Cryptophyceae
" Dinophyceae I. I
--- p
~-
Li1Iu-Feb May Aug Nov 3,000 2,500 E 2,000 E
E 1,500 500 n
Li ml m*
Feb May Aug Nov Figure 3-8.
Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 5.0 in Lake Norman during 2009.
3-32
5,000
" Chlorophyceae
" Chrysophyceae
" Myxophyceae
" Other O Bacilariophyceae
" Cryptophyceae
" Dinophyceae 4,000 3,00 3,000
- r. 2,000 0)
I---
1,000 0
.1~I Feb May Aug Nov 4,000 3,500 3,000 E
E 2,500 E 2,000
> 1,500 1,000 500 0
.4.
I F=9 L11' Feb May Aug Nov Figure 3-9.
Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 9.5 in Lake Norman during 2009.
3-33
5,000 4,000
-J E
E-3,000
- 2,000 0
1,000 0
4,000 3,500 S3,000 E
E 2,500 E 2,000
> 1,500 1,000
- Chlorophyceae
= Cryptophyceae M Other DBacillariophyceae 0 Chrysophyceae
- Myxophyceae
- Dinophyceae Feb May Aug Nov 500 0
Feb May Aug Nov Figure 3-10.
Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 11.0 in Lake Norman during 2009.
3-34
5,000
-,4,000
.-J S3,000 S2,000 0
1,000 0
4,000 3,500 E 3,000 -
2,500-E 2,000 -
500
> 1,500 -
o0 1,000 500 -
0 -
Feb May Aug Nov "t-........................................
May Feb Aug Nov Figure 3-11.
Class composition (mean density and biovolume) of phytoplankton from euphotic zone samples collected at Location 15.9 in Lake Norman during 2009.
3-35
CHAPTER 4 ZOOPLANKTON INTRODUCTION The objectives of the Lake Norman Maintenance Monitoring Program for zooplankton are to:
- 1. describe and characterize quarterly/seasonal patterns of zooplankton standing crops at selected locations on Lake Norman; and
- 2. compare and evaluate, where possible, zooplankton data collected during 2009 with historical data collected during the period 1987 - 2008.
Studies conducted prior to the Lake Norman Maintenance Monitoring Program, using monthly zooplankton data from Lake Norman, showed that zooplankton populations demonstrated a bimodal seasonal distribution with highest values generally occurring in the spring and a less pronounced fall peak. Considerable spatial and year-to-year variability has been observed in zooplankton abundance in Lake Norman (Duke Power Company 1976, 1985; Hamme 1982; Menhinick and Jensen 1974). Since quarterly sampling was initiated in August 1987, distinct bimodal seasonal distribution has been less apparent due to the lack of transitional data between quarters.
METHODS AND MATERIALS Duplicate 10-m to surface and bottom to surface net tows were taken at Locations 2.0, 5.0, 9.5, 11.0, and 15.9 in Lake Norman (Figure 2-1) during each season: winter (February),
spring (May), summer (August), and fall (November) 2009. For discussion purposes the 10-m to surface tow samples are called "epilimnetic" samples and the bottom to surface net tow samples are called "whole-column" samples.
Locations 2.0 and 5.0 are defined as the "mixing zone" and Locations 9.5, 11.0 and 15.9 are defined as "background" locations. Field and laboratory methods for zooplankton standing crop analysis were the same as those reported in Hamme (1982). Zooplankton standing crop data from 2009 were compared with corresponding data from quarterly monitoring begun in August 1987.
4-1
RESULTS AND DISCUSSION Total Abundance Highest epilimnetic zooplankton densities at Lake Norman locations have predominantly been observed in the spring, with winter peaks observed about 25% of the time. Peaks were observed only occasionally in the summer and fall (Duke Energy 2009). During 2009, there was a considerable amount of variability in annual maxima among Lake Norman locations.
The annual epilimnetic maxima were recorded from Locations 2.0, 5.0, and 9.5 in the fall, while Locations 11.0 and 15.9 demonstrated their peak annual densities in the spring and winter, respectively (Table 4-1 and Figures 4-1 and 4-2). The lowest epilimnetic densities occurred at Locations 2.0, 5.0, and 9.5 in the spring, while Locations 11.0 and 15.9 showed annual minima in the summer. Epilimnetic zooplankton densities ranged from a low of 34,507/M3 at Location 5.0 in May, to a high of 267,781/m 3 at Location 15.9 in February.
Maximum densities in 2009 whole-column samples were observed at all locations in the fall.
The seasonal whole-column minima at Locations 2.0, 5.0, and 9.5 occurred in the spring, while minima at Locations 11.0 and 15.9 were observed in the summer (Table 4-1 and Figure 4-1). Whole-column densities ranged from a low of 26,754/M3 at Location 2.0 in May, to 185,512/M3 at Location 15.9 in November.
During 2009, as has been the case in all past years, total zooplankton densities were most often higher in epilimnetic samples than in whole-column samples (Duke Energy 2009).
This is related to the ability of zooplankton to orient vertically in the water column in response to physical and chemical gradients and the distribution of food sources, primarily phytoplankton, which are generally most abundant in the euphotic zone (Hutchinson 1967).
Since epilimnetic zooplankton communities are far more representative of overall seasonal and temporal trends, most of the following discussion will focus primarily on zooplankton communities in this area of the water column.
Spatial distribution varied among locations from season to season. During winter and spring, lower average densities were observed from the mixing zone, as compared to background locations. During summer and fall this trend was not as apparent (Table 4-1; Figures 4-1 and 4-2). Location 15.9, the uppermost background location, had higher epilimnetic densities than mixing zone locations during winter and spring, while the spatial maxima in summer and fall occurred at Location 9.5 (Table 4-1). This spatial trend was similar to that of the 4-2
phytoplankton (see Chapter 3). In most previous years of the Program, background locations had higher mean densities than mixing zone locations (Duke Energy 2009 and Figures 4-3 through 4-6).
Epilimnetic zooplankton densities during 2009 were most often within historical ranges (Figures 4-3 through 4-6). The exceptions were at Location 15.9 in the winter and Location 5.0 in the fall.
On both occasions, these locations demonstrated long-term seasonal maximum densities (Figures 4-3 and 4-6).
The highest winter densities recorded from Locations 2.0 and 11.0 occurred in 1996, while the winter maximum at Location 9.5 was recorded in 1995 (Figure 4-3). The winter maximum from Location 5.0 occurred in 2004, while the long-term winter maximum from Location 15.9 occurred in 2009. Long-term maximum densities for spring were observed at Locations 2.0 and 5.0 in 2005, while the highest spring values from Locations 11.0 and 15.9 occurred in 2002. The highest spring peak at Location 9.5 was observed in 2005 (Figure 4-4). Long-term summer maxima occurred in 1988 at Locations 2.0, 5.0, and 11.0, while summer maxima at Locations 9.5 and 15.9 occurred in 2007 and 2003, respectively (Figure 4-5). Long-term maxima for the fall occurred at Locations 2.0, 9.5, and 11.0 in 2006. The long-term fall maximum at Location 5.0 occurred in 2009, while Location 15.9 demonstrated its fall maximum in 1996 (Figure 4-6).
Year-to-year fluctuations of densities in the mixing zone during the winter have occasionally been quite striking, particularly between 1991 and 1997. From 1998 - 2003, year-to-year fluctuations in the mixing zone were less apparent. Since 2004, higher annual fluctuations were apparent. From 1990 - 2003, the densities at mixing zone locations in the spring, summer, and fall demonstrated moderate degrees of year-to-year variability, and the long-term trend at mixing zone locations in the spring had been a gradual, long-term increase through 2005. During the spring of 2006, zooplankton densities in the mixing zone declined sharply, as compared to 2005, but were well within earlier historical ranges. During the spring of 2007, mixing zone locations demonstrated increases followed by sharp declines at both locations in 2008. In the spring of 2009, slight increases were noted. From 1989 -
2008, year-to-year fluctuations in the mixing zone during the summer were comparatively low, with the exception of a sharp increase in density at Location 5.0 in 2007. This was followed by a decline in 2008 and then increases in 2009. During fall periods of 1989 -
2008, mixing zone densities showed minimal fluctuations in the low range with the exceptions of 2006 and 2009 when values at both locations increased sharply. In fact, the 4-3
long-term fall peak at Location 5.0 was observed in 2009.
The background locations continue to exhibit considerable year-to-year variability in all seasons and all but Location 15.9 in the fall demonstrated higher densities in 2008 than in 2007 (Figures 4-3 through 4-6).
Community Composition One hundred and twenty-three zooplankton taxa have been identified since the Lake Norman Maintenance Monitoring Program began in August 1987 (Table 4-2). Fifty-three taxa were identified during 2009, as compared to 48 recorded for 2008 (Duke Energy 2009).
During 2008, copepods were dominant in two-thirds of the samples (Duke Energy 2009).
During 2009, dominance shifted toward the rotifers, as was the case in 2007, and these zooplankters were dominant in over 60% of the samples (Table 4-1).
Copepods were dominant in both epilimnetic and whole-column samples at Locations 2.0, 5.0 and 9.5 in the spring of 2009, and were dominant in whole-column samples from Locations 2.0, 9.5, and 11.0 during the summer. Rotifers were the dominant forms in all whole-column samples and in epilimnetic samples from Locations 11.0 and 15.9 during the winter. Rotifers were also dominant in both epilimnetic and whole-column samples at Locations 11.0 and 15.9 during the spring. During the summer, rotifers dominated epilimnetic samples at Locations 2.0, 5.0, and 9.5, as well as the whole-column sample at Location 9.5. During the fall, they were dominant in all samples. Cladocerans, typically the least abundant forms, were dominant in epilimnetic samples from Locations 2.0, 5.0, and 9.5 in the winter, in epilimnetic samples from Locations 11.0 and 15.9 in the summer, and in the whole-column sample from Location 15.9, also in the summer (Table 4-1). During most years, microcrustaceans (copepods and cladocerans) dominated mixing zone samples, but were less important among background locations (Figures 4-7 and 4-8). Compared to 2008, rotifers showed substantial increases in relative abundances in both the epilimnetic and whole-column samples of the mixing zone.
In fact, the percent composition of rotifers had increased dramatically since 2008 (Figure 4-7). This substantial increase in the relative abundances of rotifers in the mixing zone was more in keeping with historical trends. At background locations rotifer relative abundances showed more moderate increases in epilimnetic and whole-column samples since 2008 and percent compositions were within historical ranges (Figure 4-8).
4-4
Copepoda As has always been the case, copepod populations were consistently dominated by immature forms (primarily nauplii) during 2009. Adult copepods seldom comprised more than 7% of the total zooplankton density at any location. Epishura was the most important genus in most adult populations during spring and in most epilimnetic samples in the winter. Tropocyclops was dominant in the epilimnion of Location 11.0 and in whole column samples of Locations 5.0, 9.5, and 11.0 in the winter. Tropocyclops was dominant in all summer samples, as well as most epilimnetic samples in the fall. Similar patterns of copepod taxonomic distributions were observed in previous years (Duke Energy 2009).
Copepods tended to be more abundant at background locations than at mixing zone locations during all but the summer of 2009 (Figure 4-9). Copepod densities peaked at mixing zone locations in the summer and at background locations in the fall. During most past years peaks from both areas were observed in the spring.
Cladocera Bosmina was the most abundant cladoceran observed in 2009 samples, as has been the case in most previous studies (Duke Energy 2009 and Hamme 1982). Bosmina often comprised greater than 5% of the total zooplankton densities in both epilimnetic and whole-column samples, and was the dominant zooplankton taxon in two winter samples (Table 4-3).
Bosminopsis was important among cladocerans in the summer when it dominated cladoceran populations in all samples. Diaphanosoma was the dominant cladoceran in all but one sample during the spring. Similar patterns of cladoceran dominance have been observed in past years (Duke Energy 2008).
Long-term seasonal trends of cladoceran densities were variable. During 2008, maximum densities in the mixing zone occurred in the winter, while peaks at background locations were observed in the spring (Figure 4-10).
From 1990 to 1993, and in 2009, peak densities occurred in the winter, while in 1994, 1995, 1997, 2000, 2004, 2005, and 2007 maxima were recorded in the spring (Figure 4-10). During 1996 and 2002, peak cladoceran densities occurred in the spring in the mixing zone, and in the summer among background locations, while in 1999 they peaked in the mixing zone during the summer and among background locations in the fall. Maximum cladoceran densities in 1998 occurred in the summer. In 2001, maximum cladoceran densities in the mixing zone occurred in the fall, while 4-5
background locations showed peaks in the winter. During 2003, maximum densities in the mixing zone occurred in the fall, while peaks among background locations were observed in the summer. Spatially, cladocerans were well distributed among most locations (Table 4-1, Figure 4-2).
Rotifera Polyarthra was the most abundant rotifer in 40% of epilimnetic whole-column samples in the spring and fall of 2009 (Table 4-3). Keratella was the most abundant rotifer in 15% of epilimnetic samples and 25% of whole-column samples, mostly in the winter. Asplanchna was the most abundant rotifer in 15% of eplimnetic and whole column samples collected mostly in the winter. Ptygura dominated rotifer populations in one epilimnetic and two whole column samples during the summer. Other rotifers with occasional dominance were Conochilus, Ploeosoma, Kellicotia, Collotheca, and Tricocerca. All of these taxa have been identified as important constituents of rotifer populations, as well as zooplankton communities, in previous studies (Duke Energy 2009 and Hamme 1982).
Long-term tracking of rotifer populations indicated high year-to-year seasonal variability.
Peak densities have most often occurred in the winter and spring, with occasional peaks in the summer and fall (Figure 4-11). During 2009, peak rotifer densities were observed at both mixing zone and background locations in the fall.
FUTURE STUDIES No changes are planned for the zooplankton portion of the Lake Norman Maintenance Monitoring Program.
SUMMARY
During 2009, seasonal maximum densities among zooplankton assemblages varied considerably and no consistent seasonal trends were observed. Maxima occurred in winter and fall, while minima most often occurred in the spring. As in past years, epilimnetic densities were higher than whole-column densities. Mean zooplankton densities tended to be higher among background locations than among mixing zone locations during 2009. Spatial 4-6
trends of zooplankton populations were similar to those of the phytoplankton in winter and spring, with increasing densities from downlake to uplake. During summer and fall, this spatial trend was not observed. From around 1997 through 2005, a year-to-year trend of increasing zooplankton densities was observed among mixing zone locations in the spring.
Densities at these locations declined sharply in 2006, followed by an increase in 2007. The densities showed a decline in 2008, followed by an increase in 2009. In most cases, densities in 2009 were higher than in 2008.
Long-term trends showed much higher year-to-year variability at background locations than at mixing zone locations.
Epilimnetic zooplankton densities were generally within ranges of those observed in previous years. The exceptions were record high densities at Location 15.9 in the winter and Location 5.0 in the fall.
One hundred and twenty-three zooplankton taxa have been recorded from Lake Norman since the Program began in 1987. Fifty-three taxa were identified in 2009, as compared to 48 in 2008.
Overall, relative abundance of copepods in 2009 decreased over 2008.
Rotifers were dominant in over 60% of all samples. The relative abundance of microcrustaceans decreased substantially in the mixing zone in 2009 and their percent compositions at these locations were in the low range.
At background locations, microcrustaceans showed less dramatic decreases during 2009 and percent compositions were within historical ranges of past years.
Historically, copepods and rotifers have most often shown annual peaks in the spring, while cladocerans continued to demonstrate year-to-year variability.
Copepods were dominated by immature forms with adults rarely accounting for more than 7% of zooplankton densities. The most important adult copepod was Tropocyclops, as was the case in previous years. Epishura was also important in winter and spring. Bosmina was the predominant cladoceran, as has also been the case in most previous years of the Program.
Bosminopsis dominated cladoceran populations during the summer, while Diaphanosoma was an important constituent of spring populations. The most abundant rotifers observed in 2009, as in many previous years, were Polyarthra, Keratella, and Asplanchna. Ptygura, Conochilus, and Ploeosoma, were also important among rotifer populations.
4-7
Lake Norman continues to support a highly diverse and viable zooplankton community.
Other than somewhat lower productivity from MNS induced mixing at Locations 2.0 and 5.0, no impacts of plant operations were observed.
4-8
Table 4-1.
Total zooplankton densities (No. X 1000/mr3), densities of major zooplankton taxonomic groups, and percent composition (in parentheses) of major taxa in the epilimnion and whole column net tow samples collected from Lake Norman in winter (February), spring (May), summer (August), and fall (November) 2009.
Locations Sample Date Sample Type Taxa 2.0 5.0 9.5 11.0 15.9 2/13/2009 Epilimnion Copepoda 10.29 12.24 31.91 34.91 28.12 (20.5)
(18.2)
(35.2)
(24.5)
(10.5)
Cladocera 22.54 29.19 38.16 35.64 46.29 (44.8)
(43.3)
(42.0)
(25.0)
(17.3)
Rotifera 17.42 25.98 20.64 71.89 193.37 (34.7)
(38.5)
(22.8)
(50.5)
(72.2)
Total 50.25 67.41 90.71 142.44 267.78 Whole-column 2.0 5.0 9.5 11.0 15.9 Depth 30 m 19 m 20 m 25 m 20 m Copepoda 9.15 10.99 17.24 24.46 26.04 (15.1)
(18.4)
(29.5)
(25.8)
(15.0)
Cladocera 15.52 17.68 16.69 21.46 29.57 (25.6)
(29.7)
(28.5)
(22.7)
(17.0)
Rotifera 35.98 30.94 24.57 48.68 118.01 (59.3)
(51.9)
(42.0)
(51.5)
(68.0)
Total 60.65 59.61 58.50 94.60 173.62 Locations Sample Date Sample Type Taxa 2.0 5.0 9.5 11.0 15.9 5/22/2009 Epilimnion Copepoda 20.95 17.27 20.28 51.87 38.52 (41.7)
(50.0)
(42.3)
(28.8)
(17.5)
Cladocera 17.22 13.18 18.99 27.05 24.70 (34.3)
(38.2)
(39.6)
(15.0)
(11.2)
Rotifera 12.08 4.06 8.70 101.20 157.25
_24_0_
(11.8)
(18.1)
(56.2)
(71.3)
Total 50.25 34.51 47.97 180.12 220.47 Whole-column 2.0 5.0 9.5 11.0 15.9 Depth 30 m 20 m 21 m 25 m 21 m Copepoda 12.37 14.45 21.80 21.71 33.08 (46.3)
(46.3)
(49.0)
(26.3)
(23.2)
Cladocera 10.58 13.81 15.74 15.84 19.00 (39.5)
(44.2)
(35.3)
(19.2)
(13.3)
Rotifera 3.80 2.97 6.99 45.13 90.41 (14.2)
(9.5)
(15.7)
(54.5)
(63.5)
Total 26.75 31.23 44.53 82.68 142.49 4-9
Table 4-1. (Continued).
Locations Sample Date Sample Type Taxa 2.0 5.0 9.5 11.0 15.9 8/5/2009 Epilimnion Copepoda 21.83 25.01 15.81 26.38 19.41 (36.7)
(39.3)
(14.9)
(27.2)
(32.8)
Cladocera 7.54 9.19 22.64 35.65 32.36 (12.7)
(14.4)
(21.3)
(36.7)
(54.7)
Rotifera 30.04 29.48 67.87 35.00 7.34 (50.6)
(46.3)
(63.8)
(36.1)
(12.4)
Total 59.41 63.68 106.32 97.03 59.11 Whole-column 2.0 5.0 9.5 11.0 15.9 Depth 30 m 20 m 21 m 25 m 21 m Copepoda 15.84 19.95 14.40 14.52 14.84 (50.4)
(48.6)
(17.9)
(37.5)
(31.0)
Cladocera 4.64 5.04 21.60 14.26 27.24 (14.7)
(12.2)
(26.8)
(36.7)
(56.9)
Rotifera 10.88 16.12 44.52 10.03 5.53 (34.6)
(39.2)
(55.3)
(25.8)
(11.5)
Total 31.46a 41.11 80.52 38.81 47.88 Locations Sample Date Sample Type Taxa 2.0 5.0 9.5 11.0 15.9 11/24/2009 Epilimnion Copepoda 13.40 12.57 29.78 23.33 19.04 (7.9)
(6.4)
(12.3)
(17.2)
(9.6)
Cladocera 7.55 8.91 10.26 4.10 1.16 (4.5)
(4.6)
(4.3)
(3.0)
(0.6)
Rotifera 148.13 173.54 201.14 108.30 178.68 (87.6)
(89.0)
(83.4)
(79.8)
(89.8)
Total 169.08 195.02 241.18 135.73 198.88 Whole-column 2.0 5.0 9.5 11.0 15.9 Depth 30 m 19 m 21 m 25 m 21m Copepoda 10.25 16.58 28.35 27.63 18.28 (11.0)
(14.9)
(16.2)
(25.5)
(9.9)
Cladocera 6.73 5.54 3.58 6.02 3.96 (7.2)
(5.0)
(2.0)
(5.6)
(2.1)
Rotifera 76.42 88.92 143.30 74.61 163.28 (81.8)
(80.1)
(81.8)
(68.9)
(88.0)
Total 93.40 111.04 175.23 108.26 185.52 a = Chaoborus (102/M 3, 0.3%)
b = Chaoborus (272/M3, 0.6%)
4-10
Table 4-2. Zooplankton taxa identified from samples collected quarterly on Lake Norman from 1987 - 2009.
Taxon 87-94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Copepoda Cyclops thomasi Forbes X
X X
X X X
X X
X X
X X
X X
X C. vernalis Fischer X
C. spp. O. F. Muller X
X X
X X
X X
X X
Diaptomus birgei Marsh X
X D. mississippiensis Marsh X
X X
X X X X
X X
X X X
X X
X X D. pallidus Herick X
X X
X X
X X
D. reighardi Marsh X
D. spp. Marsh X
X X
X X
X X
X X
X X Epishurafluviatilis Herrick X
X X
X X
X X
X X
X X
X X
X X
Ergasilus spp. Smith X
X Eucyclops agilis (Koch)
X E. prionophorus Kiefer X
Mesocyclops edax (S. A. Forbes)
X X
X X
X X
X X
X X
X X
X X
X X
M spp. Sars X
X X
X X
X X
X Paracyclops limbricatus v. poppei X
'I Tropocyclops prasinus (Fischer)
X X
X X
X X
X X
X X
X X
X X
X X
T spp. (Fischer)
X X
X X
X X
X X
X X
X Cladocera Alona spp.Baird X
X X
X Alonella spp. (Birge)
X X
Bosmina longirostris (0. F.M.)
X X
X X
X X
X X
X X
X X
X X
B. spp. Baird X
X X
X X
X X
X Bosminopsis dielersi Richard X
X X
X X
X X
X X
X X
X X
X X
X Ceriodaphnia lacustris Birge X
X X
X X
X X
X X
X X
X X
C. spp. Dana X
X X
X X
X X
X X
X
-X X
Chydorus spp. Leach X
X X
X X
X X X
X X
Daphnia ambigua Scourfield X
X X
X X
X X
X X
X X
D. catawba Coker X
X X
D. galeata Sars X
D. Iaevis Birge X
X D. longiremis Sars X
X X
X X
X D. lumholzi Sars X
X X
X X
X X
D. mendotae (Sars) Birge X
X X
X X
X D. parvulda Fordyce X
X X
X XX X
X X
X X
X X
X X
X D. pulex (de Geer)
X X
X X
D. pulicaria Sars X
X D. retrocurva Forbes X
X X
X X
X X
X X
X X
D. schodleri Sars X
D. spp. Mullen X
X X
X X
X X
X X
X X
X X
X X
X Diaphanosoma brachyurum (Lievin)
X X
X X
X X
X X
X X
X X
X D. spp. Fischer X
X X
X X
X X
X X
X Disparalona acutirostris (Birge)
X Eubosmina spp. (Baird)
X Holopedium amazonicum Stin.
X X
X X
X X
X X
X X
X X
X H. gibberum Zaddach X
X X
Ex 4-11
Table 4-2. (Continued).
Page 2 of 3 Taxon 87-93 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 H. spp. Stingelin X
X X
X X
X X
X X
Ilyocryptus sordidus (Lieven)
X L spinifer Herrick X
I. spp. Sars X
X X
X Latona setifera (O.F. Muller)
X Leptodora kindtii (Focke)
X X
X X
X X
X X
X X
X X
X X
X X
Leydigia acanthoceroides (Fis.)
x L. spp. Freyberg X
X X
X X
X X Moina spp. Baird X
I Monospilus dispar Sars X
Oxurella spp. (Sars)
X Pleuroxus hamulatus Birge X
X P. spp. Baird X
Sida crystallina 0. F. Muller X
Simocephalus expinosus (Koch)
X Simocephalus spp. Schodler X
Rotifera Anuraeopsis fissa (Gosse)
X X
A. spp. Lauterbome X
X X
X X
X X
Asplanchna brightwelli Gosse X
X A. priodonta Gosse X
X X
X X
A. spp. Gosse X
X XX X X X X X XXX X
X X Brachionus calyciflorus X
Brachionus caudata Bar. & Dad.
X B. bidentata Anderson X
B. havanensis Rousselet X
X B. patulus 0. F. Muller X
X B. spp. Pallas X
X X
I X Chromogaster ovalis (Berg.)
X X
X X
I X
X X
X X
C. spp. Lauterborne X
X X
Collotheca balatonica Harring X
X X
X X
X X
X X
X X
X X
C. mutabilis(Hudson)
X X
X X
X X
X X
X X
X X
C. spp. Harring X
X X
X X
X X
X X
X X
Colurella spp. Bory de St. Vin.
X I
I I
I I
Conochiloides dossuarius Hud.
X X
X X
X X
X X
X X
X X
X C spp. Hlava X
X X
X X
X Conochilusunicornis(Rouss.)
X X
X X
X X
X X
X X
X X
X X
C. spp. Hlava X
X X
X X
X X
Filinia spp. Bory de St. Vincent X
X X
Gastropus stylifer Imhof X
X X
X X
X X
G. spp. Imhof X
X X
X X
X Hexarthra mira Hudson X
X X
X X
X X
X X
H. spp. Schmada X
X X
X X
Kellicottia bostoniensis (Rou.)
X X
X X
X X
X X
X X
X X
X X
X X
K longispinaKellicott X
X X
X X
X X
X X X
X X
X K spp. Rousselet X
X X
X X
X X
X X X
Keratella americana Carlin IIIX K cochlearis Raderorgan X
X X
X X
X 4-12
Table 4-2. (Continued).
Page 3 of 3 Taxon 87-93 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 K taurocephala Myers X
X X X X
X K spp. Bory de St. Vincent X
X X
X X
X X
X X
X X
X X
X X
Lecane luna 0. F. Muller X
Lecane spp. Nitzsch X
X X
X X
X X
X X Macrochaetus subquadratus P.
X X
M spp. Perty X
X X
X X
X Monommata spp. Bartsch X
X Monostyla stenroosi (Meiss.)
X M spp. Ehrenberg X
X X
X X
Notholca spp. Gosse X
X X
Platyias patulus Harring X
Ploesoma hudsonii Brauer X
X X
X X
X X
X X
X X
X X
X X
X P. truncatum (Levander)
X X
X X
X X
X X
X x X
X X
x X
P. spp. Herrick X
X X
XX X
Polyarthra euryptera (Weir.)
X X
X X
X P. major Burckhart X
X X
X X
X X
X X
X X
P. vulgaris Carlin X
X X
X X
X X
X X
X X
X X
P. spp. Ehrenberg X
X X
X X
X x
X x
X X
X X
X X
X Pompholyx spp. Gosse X
Ptygura libra Meyers X
X X
X X
X X
X X
X X
P. spp. Ehrenberg X
X X
X X
X X
Synchaeta spp. Ehrenberg X
X X
X X
x X
X X
X X
X X
X X
X Trichocerca capucina (Weir.)
X X
x X
X X
T. cylindrica (Imhof)
X X
X X
X X
X X
X X
X X
X T. longiseta Schrank X
X X
X T. multicrinis (Kellicott)
X X
X X
X X
X X
X X
X T porcellus (Gosse) x X
X x
x X
x T. pusilla Jennings X
T. similis Lamark X
X T spp. Lamark X
7 X
X X X X
X X
X X X X
x X
x Trichotria spp. Bory de St. Vin.
X X
X Unidentified Bdelloida X
X X
X X
X X
Unidentified Monogonata Unidentified Philodinidae X
X Unidentified Rotifera X
X X
X X X
Insecta Chaoborus spp. Lichtenstein X
X X
X X
X X
X X
X X
Ostracoda (unidentified)
X X
X 4-13
Table 4-3.
Dominant copepod (adults), cladoceran, and rotifer taxa and their percent composition (in parentheses) of the copepod, cladoceran and rotifer densities by location and sample period in Lake Norman in 2009.
Locations Winter Spring Summer Fall Copepoda:
Epilimnion 2.0 Epishura (3.1)
Epishura (5.7)
Tropocyclops (5.7)
Tropocyclops (7.0)r 5.0 Epishura (1.9)
Epishura (7.1)
Tropocyclops (5.9)
Tropocyclops (3.1) 9.5 Epishura (2.6)
Epishura (9.8)
Tropocyclops (9.3)c Tropocyclops (7.5)'
11.0 Tropocyclops (1.9)
Epishura (4.5)
Tropocyclops (4. 1)c Mesocyclops (2.8) 15.9 No adults present Epishura (4.1)
Tropocyclops (3.2)c Tropocyclops (5.3)c Copepoda:
Whole-column 2.0 No adults present Epishura (7.8)
Tropocyclops (5.9)
Tropocyclops (3.0) 5.0 Tropocyclops (13.5)
Epishura (10.0)c Tropocyclops (15.1)c Epishura (2.5) 9.5 Tropocyclops (4.0)
Epishura (7.3)
Tropocyclops (2.9)
Epishura (12.3) 11.0 Tropocyclops (5.5)
Epishura (5.4)
Tropocyclops (10.9)
Epishura (4.3) 15.9 Epishura (1.1)c Mesocyclops (1.4)
Tropocyclops (8.6)
Tropocyclops (1.6)
Cladocera:
Epilimnion 2.0 Bosmina (94.6)
Diaphanosoma (57.0)
Bosminopsis (70.7)
Bosmina (90.0) 5.0 Bosmina (67.7)
Diaphanosoma (54.8)
Bosminopsis (85.3)
Bosmina (97.8) 9.5 Bosmina (98.4)
Diaphanosoma (36.2)
Bosminopsis (71.8)
Bosmina (94.6) 11.0 Bosmina (96.4)
Diaphanosoma (61.4)
Bosminopsis (74.0)
Bosmina (75.0) 15.9 Bosmina (86.8)
Diaphanosoma (44.0)
Bosminopsis (74.2)
Bosmina (100.0)
Cladocera:
Whole-column 2.0 Bosmina (98.1)
Diaphanosoma (43.4)
Bosminopsis (65.2)
Bosmina (86.3) 5.0 Bosmina (98.0)
Diaphanosoma (50.0)
Bosminopsis (74.6)
Bosmina (92.3) 9.5 Bosmina (95.8)
Diaphanosoma (39.2)
Bosminopsis (76.1)
Bosmina (84.6) 11.0 Bosmina (86.2)
Diaphanosoma (63.4)
Bosminopsis (74.1)
Bosmina (60.1) 15.9 Bosmina (98.0)
Bosmina (61.0)
Bosminopsis (65.3)
Bosmina (92.6)
' = Only adults present in samples.
4-14
Table 4-3. (Continued).
Locations Winter Spinn Summer Fall Rotifera:
Epilimnion 2.0 Keratella (72.01)
Polyarthra (54.2)
Conochilus (58.2)
Polyarthra (95.4) 5.0 Keratella (80.0)
Kellicottia (50.9)
Ptygura (52.1)
Polyarthra (97.3) 9.5 Asplanchna (47.0)
Polyarthra (87.1)
Collotheca (71.2)
Polyarthra (84.3) 11.0 Asplanchna (57.7)
Keratella (80.1)
Trichocera (32.3)
Polyarthra (66.3) 15.9 Asplanchna (60.7)
Polyarthra (68.2)
PIoeosoma (36.3)
Polyarthra (47.0)
Rotifera:
Whole-column 2.0 Keratella (81.3)
Polyarthra (53.4)
Conochilus (43.9)
Poluarthra (90.6) 5.0 Keratella (90.2)
Keratella (51.6)
Ptygura (34.5)
Polyarthra (96.9) 9.5 Keratella (67.3)
Polyarthra (59.4)
Ptygura (66.5)
Polyarthra (79.4) 11.0 Asplanchna (44.8)
Polyarthra (81.9)
Asplanchna (31.3)
Polyarthra (65.7) 15.9 Asplanchna (57.6)
Polyarthra (63.7)
Ploeosoma (49.1)
Keratella (52.5) 4-15
Epilimnetic I --
Winter --*-Sprng --*-Summer --- Fall A"
C) a)3 300 250 200 150 100 50 0
2.0 5.0 9.5 11.0 Location 15.9 Whole-column S-----Winter Spring --*-Summer -F-FalI 0
0 6
z Z%
C a) 200 175 150 125 100 75 50 25 0
2.0 5.0 9.5 11.0 Location 15.9 Figure 4-1. Total zooplankton density by location for samples collected in Lake Norman in 2009.
4-16
Winter Spring 300 mRotners OCladocerans ECopepods 300 mRotifers oCladocerans ACopepods 250 250 E
E a0 8o 200 200 4
Z 6
150
<5150-
-100 100 c
C 0
500 0
0 '7
-G 2.0 5.0 9.5 11.0 15.9 2.0 5.0 9.5 11.0 15.9 Location Location Summer Fall 300 300 2 Rotfer3 OCladocerans lCopepodl lRotifers 0 Cladocerans eCopepods 250 E
250 o0 C
200 CO 200 6
150 150 z
2 100 100 C
C 50 50 00 2.0 5.0 9.5 11.0 15.9 2.0 5.0 9.5 11.0 15.9 Location Location Figure 4-2.
Zooplankton community composition by sample period and location for epilimnetic samples collected in Lake Norman in 2009.
4-17
0 0
U) 225 200 175 150 125 100 75 50 25 0
300 Mixing Zone Locations Winter
-ZO 5.0--------------------
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Background Locations i-9.5 110 "--15-79 T-
¥ V
v 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year E 250 200 X
o 150 i7_1 100 Co 50 0
Figure 4-3.
Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the winter periods of 1988 - 2009 (clear data points represent long-term maxima).
4-18
0 z
0S 225 200 175 150 125 100 75 50 25 0
600 500 0
o 400 X
6 300 200 o
100 Mixing Zone Locations Song 2-_--0
-'-5.0 -
88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Background Locations 9.-5 -11.0
-15.9 0
88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the spring periods of 1988 - 2009 (clear data points represent long-term maxima).
Figure 4-4.
4-19
Mixing Zone Locations Summer E
X 6
C 0<
0 150 125 100 75 50
-.-2.0 :-5.07 25 0
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Background Locations 0
X05 x.
6) tC-300 250 200 150 100 50
-9.5
-u-11.0 -15.9]
A ILI A A
A,,
V\\,A 0
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the summer periods of 1987 - 2009 (clear data points represent long-term maxima).
Figure 4-5.
4-20
Mixing Zone Locations Fall 0
X 6
S 0-0)
In 200 175 150 125 100 75 50 25 0
I I
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Background Locations 500 400 300 X
200 100 F-9.5 11.0 --- 15.
A
/A\\
Y 7
, 'r 0
87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 Year Total zooplankton densities by location and year for epilimnetic samples collected in Lake Norman in the fall periods of 1987 - 2009 (clear data points represent seasonal maxima).
Figure 4-6.
4-21
Mixing Zone: Epilimnion
] Rotifers 13 Cladocerans E Copepods 100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
I I--
88 89 90 9192 93 94 95 96 97 98 9900 0102 03 04 05 06 07 08 09 Mixing Zone: Whole-column 100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
88 89 90 91 92 93 94 95 96 9798 99 00 01 02 03 04 05 06 07 08 09 Years Figure 4-7.
Annual percent composition of major zooplankton taxonomic groups from mixing zone locations (Locations 2.0 and 5.0 combined) during 1988 - 2009 (Note: does not include Location 5.0 in the fall of 2002 or winter samples from 2005).
4-22
Background. Epilimnion I
0 Rotifers 0 Cladocerans 1U Copepods 100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
88 89 90 9192 93 94 95 96 97 98 99 00 0102 03 04 05 06 07 08 09
Background:
Whole-column 100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
88 89 90 91 92 93 94 95 96 9798 99 00 0102 03 04 05 06 07 08 09 Years Figure 4-8.
Annual percent composition of major zooplankton taxonomic groups from background locations (Locations 9.5, 11.0, and 15.9 combined) during 1988 -
2009 (Note: does not include winter samples from 2005).
4-23
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1991 1992 1993 4
199 1996 1997 1996 1999 200 01 2 002 2003 2004 2006 20 00 20 Seasons and Years Figure 4-9. Copepod densities during each season of each year among epilimnetic samples collected in Lake Norman from 1990 -
2009 (mixing zone = mean of Locations 2.0 and 5.0; background = mean of Locations 9.5, 11.0, and 15.9).
()0TTFT T
-T-7-T7--T-T7-T-T-T7-1
- .rrnFTT.-T---T7-T-T7-T-T--m=.TTTFF1 I
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i l H
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1991 1992 1993 1994 1995 95 19 1996 1999 2=0 2001 2002 2003 2004 2006 2006 2007 2
2009 Seasons and Years Figure 4-10. Cladoceran densities during each season of each year among epilimnetic samples collected in Lake Norman from 1990 -
2009 (mixing zone = mean of Locations 2.0 and 5.0; background = mean of Locations 9.5, 11.0, and 15.9).
0 350 ------
300 jLH I
Ill 1 I
. I I1 250 tttiHHh-tttt}HH I
I 4 I l i H Vi i lllt il,_
200 - 111.....I.;.1--L-L-L.'.
1111-r<iiii iii, ii llii l Ii i!,il iii iiiiiiW K W"H 1 i'iH i!
otil iJ i
100 i'.
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I i t i 11 ii 0~0
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'ý]E=
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"; ti "i M*
14 1991 1992 193 19 95 1M' M
20 0I 20 03 21207 20 0
Seasons and Years Figure 4-11.
Rotifer densities during each season of each year among epilimnetic samples collected in Lake Norman from 1990 -
2009 (mixing zone = mean of Locations 2.0 and 5.0; background = mean of Locations 9.5, 11.0, and 15.9).
ON
CHAPTER 5 FISHERIES INTRODUCTION In accordance with the NPDES permit for McGuire Nuclear Station (MNS) and associated requirements from the North Carolina Wildlife Resources Commission (NCWRC), Duke Energy (DE) personnel monitored specific fish population parameters in Lake Norman during 2009. The components of this program were:
- 1. spring electrofishing survey of littoral fish populations with emphasis on age, growth, size distribution, and condition of black bass (spotted bass Micropterus punctulatus and largemouth bass M salmoides);
- 2. fall electrofishing survey to assess black bass young-of-year abundance;
- 3. summer striped bass Morone saxatilis mortality surveys;
- 4. winter striped bass gill net survey with the NCWRC with emphasis on age, growth, and condition;
- 5. fall hydroacoustic and purse seine surveys of pelagic fish abundance and species composition; and
- 6. support NCWRC fall white crappie Pomoxis annularis and black crappie P.
nigromaculatus trap-net survey with emphasis on age and growth.
METHODS AND MATERIALS Spring Electrofishing Survey An electrofishing survey was conducted in Lake Norman in April at three areas (Figure 5-1):
near Marshall Steam Station (MSS, Zone 4), a reference (REF, Zone 3) area located between MNS and MSS, and near MNS (Zone 1). Ten 300-m shoreline transects were surveyed in each area and were identical to historical locations surveyed since 1993. Transects included habitats representative of those found in Lake Norman. Shallow flats where the boat could not access within 3 to 4 m of the shoreline were excluded. All sampling was conducted during daylight, when water temperatures were expected to be between 15 and 20 'C.
5-1
Surface water temperature ('C) was measured with a calibrated thermistor at each location.
Stunned fish were collected by two netters and identified to species. Fish were enumerated and weighed in aggregate by taxon, except for spotted bass and largemouth bass, where total length (TL, mm) and weight (g) were obtained for each individual collected. Catch per unit effort (number of individuals/3,000 m) and the number of species were calculated for each sampling area. Sagittal otoliths were removed from all black bass > 125 mm long (black bass
< 125 mm were assumed to be age 1 because young-of-year black bass are historically not collected in spring surveys) and sectioned for age determination (Devries and Frie 1996).
Condition (Wr) based on relative weight was calculated for spotted bass >100 mm long and largemouth bass >150 mm long, using the formula Wr = (W/Ws) x 100, where W = weight of the individual fish (g) and W, = length-specific mean weight (g) for a fish as predicted by a weight-length equation for that species (Anderson and Neumann 1996). Growth rates (age 2 to 6 years) were compared between species and among areas with analysis of variance (c =
0.05) and Tukey's pairwise comparison (Analytical Software 2008).
Fall ElectrofishingYoung-of-Year Bass Survey An electrofishing survey was conducted in November at the same three areas (MSS, REF, MNS) as the spring survey and consisted of five 300-m shoreline transects at each area.
Again, shallow flats where the boat could not access within 3 to 4 m of the shoreline were excluded.
Stunned black bass were collected by two netters, identified to species, and individually measured and weighed. A young-of-year "cut off' of 150 mm, based upon historical length-frequency data, was used for data analysis.
Summer Striped Bass Mortality Surveys Mortality surveys were conducted weekly during July and August to specifically search for dead or dying striped bass in Zones 1 to 4. All observed dead striped bass were collected during these surveys and their location noted. Individual TL was measured prior to disposal.
5-2
Striped Bass Netting Survey Striped bass were collected for age, growth, and condition determinations in December by DE and NCWRC personnel. At least four monofilament nets (76.2 m long x 6.1 m deep),
two each containing two 38.1-m panels of 38-and 51-mm square mesh and two each containing 38.1-rn panels of 63-and 76-mm square mesh, were set overnight in areas where striped bass were previously located. After three nights of low striped bass catch rates local fishermen were asked to retain their catch providing additional fish. Individual total lengths and weights were obtained for all striped bass collected. Sagittal otoliths were removed to determine age, growth, and condition, as described previously for largemouth bass.
Additionally, all catfish collected were identified and enumerated by species.
Fall Hydroacoustics and Purse Seine Surveys Abundance and distribution of pelagic forage fish in Lake Norman were determined using mobile hydroacoustic (Brandt 1996) and purse seine (Hayes et al. 1996) techniques. The lake was divided into six zones (Figure 5-1) due to its large size and spatial heterogeneity. An annual mobile hydroacoustic survey of the lake was conducted in mid-September with multiplexing, side-and down-looking transducers to detect surface-oriented fish and deeper fish (from 2.0 m depth to the bottom), respectively.
Annual purse seine samples were also collected in mid-September from the downlake (Zone 1), midlake (Zone 2), and uplake (Zone 5) areas of Lake Norman. The purse seine measured 122.0 x 9.1 m, with a mesh size of 4.8 mm. A subsample of forage fish collected from each area was used to estimate taxa composition and size distribution.
Fall Crappie Trap-Net Survey The Lake Norman black and white crappie population was surveyed by NCWRC personnel in late October as described by Nelson and Dorsey (2005). Fifteen locations in each of Zones 1, 2, and 3 were sampled with trap nets over two consecutive nights for a total of 90 net nights.
Trap nets measured 1.83 x 0.91 x 0.91 m with a 15.24 x 0.91-m lead and 1.91-cm mesh.
Individual total lengths and weights were obtained for all crappie collected. Sagittal otoliths were removed for age and growth analysis.
5-3
RESULTS AND DISCUSSION Spring Electrofishing Survey Spring 2009 electrofishing resulted in the collection of 5,227 individuals (24 species and two centrarchid hybrid complexes) weighing 314.36 kg at average water temperatures ranging from 16.5 to 21.2 'C (Table 5-1). The survey consisted of 1,418 individuals (20 species and two centrarchid hybrid complexes) weighing 152.64 kg in the MSS area, 2,219 fish (19 species and two centrarchid hybrid complexes) weighing 102.34 kg in the REF area, and 1,590 individuals (16 species and two hybrid centrarchid complexes) weighing 59.38 kg in the MNS area (Figure 5-2).
Overall, bluegill Lepomis macrochirus dominated samples numerically, while bluegill, common carp Cyprinus carpio, largemouth bass, and spotted bass dominated samples gravimetrically.
The total number of individuals collected in spring 2009 was highest in the REF area, intermediate in the MNS area, and lowest in the MSS area. Although the total number of individuals was also highest in the REF area from 2006 - 2008, there is no apparent temporal trend in the number of individuals collected within or among areas since 1993.
Total biomass of fish in 2009 was highest in the MSS area, intermediate in the REF area, and lowest in the MNS area, following the spatial trend of previous years. This spring trend in Lake Norman fish biomass supports the spatial heterogeneity theory noted by Siler et al.
(1986).
The authors reported that fish biomass was higher uplake than downlake due to higher levels of nutrients and resulting higher productivity uplake versus downlake. The spatial heterogeneity theory is further supported by higher concentrations of chlorophyll a, greater phytoplankton standing crops, and elevated epilimnetic zooplankton densities in uplake compared to downlake regions of Lake Norman (see Chapters 3 and 4). There is no apparent temporal trend in the biomass of fish collected within each area since 1993.
Spotted bass, thought to have originated from angler introductions, were first collected in Lake Norman in the MNS area during a 2000 fish health assessment survey. They have increased in number of individuals and biomass since the 2001 spring electrofishing survey (Figure 5-3) and, in 2009, were most abundant in the REF area, intermediate in the MNS area, and least abundant in the MSS area. Similarly, biomass was highest in the REF area, intermediate in the MNS area, and lowest in the MSS area. In 2009, small spotted bass (<
150 mm) dominated the black bass catch in all areas (Figures 5-4a and b).
5-4
Spotted bass mean Wr ranged from 66.6 for fish 350 to 399 mm in the MNS area to 81.9 for fish 250 to 299 mm also in the MNS area (Figure 5-5a). Overall, spotted bass mean Wr values were highest in the MSS area (78.4), intermediate in the REF area (74.6), lowest in the MNS area (73.0), and within the range of observed historical values (71.4 to 82.3) (Duke Power unpublished data, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Relative to 2008, the number of individual largemouth bass in 2009 decreased in all areas following a downward trend (Figure 5-6a). Largemouth bass biomass also decreased in all areas (Figure 5-6b). Number of individuals and biomass at all areas were generally similar to data from 2006 - 2008, and the lowest recorded since sampling began in 1993. As in most years, 2009 largemouth bass number of individuals and biomass were highest in the MSS area, intermediate in the REF area, and lowest in the MNS area following a longitudinal gradient reported from similar reservoirs in Georgia (Maceina and Bayne 2001) and Kentucky (Buynak et al. 1989).
Largemouth bass were distributed across all size classes (Figure 5-4b) with mean Wr ranging from 64.6 for fish 300 to 349 mm in the MNS area to 94.0 for fish 400 to 449 mm in the MNS area (Figure 5-5b). The low number of largemouth bass collected diminishes the significance of these comparisons. Overall, largemouth bass mean Wr values were highest in the MNS and MSS areas (83.6), lowest in the REF area (76.5), and within the range of observed historical values (76.0 to 89.9; Duke Power unpublished data, 2 0 04 a, 2005; Duke Energy 2006, 2007, 2008, 2009).
Largemouth bass numbers were inadequate for growth rate comparisons with spotted bass or with previous years of data (Table 5-2). However, both black bass species when combined showed a decreased growth rate in the REF area relative to the MSS and MNS areas, a difference also reported in the 2009 report when comparing largemouth bass growth rates over all years (1993 -
1994, 2003 - 2008) of data (Duke Energy 2009).
Additionally, largemouth bass had significantly lower growth rates from 1993 - 1994 than from 2003 -
2008 (Table 5-3).
Although the largemouth bass population parameters have decreased sharply since the introduction of spotted bass, a causal effect, although likely, is indeterminate due to possible confounding effects of other introduced species, including alewife Alosa pseudoharengus and white perch Morone americana (Kohler and Ney 1980, Madenjian et al. 2000).
5-5
Fall Electrofishing Young-of-Year Black Bass Survey Fall 2009 electrofishing resulted in the collection of 237 spotted, 7 largemouth, and 12 hybrid black bass young-of-year (< 150 mm), continuing an increasing trend in spotted bass young-of-year numbers since 2005 (Figure 5-7).
As in 2005 - 2008, young-of-year black bass numbers were highest in the MSS area.
Summer Striped Bass Mortality Surveys In 2009, a total of 362 dead striped bass were collected during weekly July and August surveys, mostly in Zone 1 (Table 5-4). Since the survey began in 1983, summer mortalities in excess of 25 dead striped bass have occurred previously in three years: 163 in 1983, 43 in 1986, and 2,610 in 2004.
Winter Striped Bass Netting Survey Striped bass (n = 101) collected in mid to late December 2009 were dominated by age 1 and 2 fish (Figure 5-8). Striped bass growth was fastest through age 3 and slowed with increasing age. Mean Wr was highest for age 4 fish (92.1) and declined thereafter. Mean Wr was 85.8 for all striped bass in 2009, above the range of observed historical values (78.5 to 84.1).
Growth and condition in 2009 were similar to historical values since consistent annual gillnetting began in 2003 (Duke Power 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
However, the predominance of age 1 and 2 striped bass collected in 2009 diminishes the significance of this comparison.
The December striped bass gillnetting also yielded 257 catfish.
Blue catfish Ictalurus furcatus (224) dominated the catch, followed by channel catfish L punctatus (19) and flathead catfish Pylodictis olivaris (14).
Fall Hydroacoustics and Purse Seine Surveys Mean forage fish densities in the six zones of Lake Norman ranged from 3,068 (Zone 1) to 20,706 (Zones 5 and 6) fish/ha in September 2009 (Table 5-5). Zone 6 fish densities were assumed to be the same as Zone 5, as the shallow nature of the riverine Zone 6 limits habitat available for acoustic sampling. The lakewide population estimate in September 2009 was 5-6
approximately 96.5 million fish, the second highest population estimate since surveys began in 1997 (Figure 5-9). As in most years since 1997, Zone 5 had the highest forage fish density estimates.
No temporal trends are evident in lakewide pelagic forage fish population estimates in Lake Norman from 1997 - 2009.
Threadfin shad Dorosoma petenense dominated the Lake Norman forage fish community purse seine survey in 2009 (88.4%), similar to surveys since 1993 (Table 5-6). Alewife, first detected in Lake Norman in 1999 (Duke Power 2000), have comprised as much as 25.0%
(2002) of mid-September pelagic forage fish surveys. Their percent composition remained relatively low from 2005 - 2008 (range = 1.7 to 5.1%) with a noticeable increase in 2009 (11.60%). The threadfin shad modal TL class increased after alewife introduction, returning to pre-introduction levels by 2005 (46 to 50 mm in 2009; Figure 5-10).
Fall Crappie Trap-Net Survey In 2009, NCWRC personnel expended 110 trap-net nights of effort in Lake Norman collecting no white crappie and 365 black crappie. Various life history data were collected for use in fish management reports by the NCWRC.
SUMMARY
In accordance with the Lake Norman Maintenance Monitoring Program for the MNS NPDES permit, specific fish monitoring programs continued during 2009.
Spring electrofishing indicated that 16 to 20 species of fish and two hybrid complexes comprised diverse fish populations in the three survey areas. The number of individuals and biomass of fish in 2009 were generally similar to those noted annually since 1993. Collections were numerically dominated by centrarchids. Largemouth bass number of individuals and biomass were the lowest recorded since sampling began in 1993. Spotted bass number of individuals and biomass continue to increase, possibly displacing largemouth bass.
During 2009, the number of summer striped bass mortalities (362) was the highest since 2004.
Mean Wr (85.8) in winter was slightly higher than in previous years although dominated by age 1 and 2 fish. Hydroacoustic sampling estimated a forage fish population of approximately 96.5 million in 2009, the second highest estimate since surveys began in 1997.
5-7
Alewife percent composition in fall purse seine surveys (11.6%) and modal threadfin shad TL class (46 to 50 mm) both increased to the highest values since 2004. The introduction of alewife and inherent, temporal fluctuations in clupeid densities contribute to the variable nature of forage fish populations.
Past studies have indicated that a balanced indigenous fish community exists in Lake Norman (Duke Power 2000, 2001, 2002, 2003, 2004a, 2005; Duke Energy 2006, 2007, 2008, 2009).
The present study adds another year of comparable data, reinforcing that conclusion. Based on the diversity and numbers of individuals in the Lake Norman littoral fish community during spring and the regular availability of forage fish to limnetic predators, it is concluded that the operation of MNS has not impaired the Lake Norman fish community.
5-8
Table 5-1.
Number of individuals (No.) and biomass (Kg) of fish collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, April 2009.
_SS RE_
Total Scientific Nane Common Name No.
Kg No.
Kg No.
Kg No.
Kg Lepisosteidae Lepisosteus osseus Longnose gar 4
7.97 4
7.97 Clupeidae Alosa pseudoharengus Alaw Ne 1
0.01 1
0.01 Dorosoma cepedianum Gizzard shad 20 8.02 5
2.77 4
2.12 29 12.91 Dorosoma petenense Threadfin shad 1
0.00 135 1.41 130 1.41 COprindae Cyprinella chlonstia Geeenfin shiner 1
0.00 23 0.07 19 0.05 43 0.13 Cyplnella nihea Vitefin shier 22 0.10 22 0.12 1
0.00 46 0.22 Cyprinus carpio Con'mon carp 25 62.17 6
12.18 2
6.11 33 80.45 Notemigonus crysoleucas Golden shiner 1
0.01 1
0.01 Notropis hudsonius Spottail shirer 8
0.07 71 0.36 67 0.50 146 0.93 Catostorridae Carpiodes cyprinus Qufilback 1
1.17 1
1.61 2
2.78 Moxostoma macrolepidotum Shorthead redhorse 1
0.34 1
0.34 Ictalurldae Ictalurus furcatus Blue catfish 1
0.99 1
2.28 2
3.26 Ictalurus punctatus Channel catfish 12 5.72 8
3.05 2
0.53 22 9.29 Py4/octis ofivaris Flathead catfish 5
1.67 15 1.96 3
0.07 23 3.71 Moronidae Morone amnercana Mte perch 11 0.57 11 0.57 Morone saxatilis Striped bass 8
8.76 2
1.76 10 10.52 Contrarchidae Lepomis auntus Redbreast sunfish 61 1.81 191 4.84 172 3.79 424 10.44 Lepomis cyanellus Green sunfish 77 1.45 49 0.98 126 2.43 Lepomisgulosus Warmouth 15 0.10 60 0.59 42 0.40 117 1.09 Lepomis macrochirus Bluegill 886 11.37 1,294 18.31 999 14.34 3,179 44.02 Lepomis microlophus Redear sunfish 51 4.71 59 6.14 34 2.49 144 13.35 Lepomis hybrid Hybrid sunfish 35 1.60 65 2.30 57 1.17 167 6.07 Micropteruspunctulatus Spotted bass 118 18.56 177 25.73 168 19.34 463 63.83 Micropterus salmoides Largersouth bass 51 21.72 26 9.36 10 4.34 87 35.42 Micrapterus hybrid Hybrid black bass 8
2.72 5
1.09 7
0.23 20 4.03 Pomaxis nigromaculatus Black crappie 1
0.38 1
0.38 Total 1,418 152.64 2.219 102.34 1,590 69.38 6,227 314.36 Total No. Species 20 19 16 24 Mean Water Temperature C) 19.2 16.5 21.2 5-9
Table 5-2.
Mean TL (mm) at age (years) for spotted bass and largemouth bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, April 2009.
Age (years)
Taxa Area 1
2 3
4 5
6 7
8 9
Spotted MSS 196 276 348 387 426 bass REF 169 254 352 392 438 501 450 MNS 194 293 332 373 376 432 Mean TL (mm) 186 274 344 384 413 466 450 Largemouth MSS 255 312 434 398 bass REF 216 294 335 377 363 374 410 413 484 MNS 184 265 326 350 375 346 504 Mean TL (mm) 218 290 331 364 391 374 385 459 484 Table 5-3. Comparison of mean TL (mm) at age (years) for largemouth bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, April 2009, to historical largemouth bass mean lengths.
Age (years)
Location and year 1
2 3
4 MSS 1974-788 170 266 310 377 MSS 19 9 3 b 170 277 314 338 MSS 1994 b 164 273 308 332 MSS 2003c 216 317 349 378 MSS 2004d 176 309 355 367 MSS 20050 190 314 358 396 MSS 20W6r 184 347 346 408 MSS 2 0 07 g 215 261 363 394 MSS 2008h 213 307 365 390 MSS 2009 255 312 REF 1 9 9 3 b 157 242 279 330 REF 1 9 9 4 b 155 279 326 344 REF 2003c 139 296 358 390 REF 2004d 143 288 364 415 REF 20050 139 307 357 386 REF 2006' 180 300 363 378 REF 20079 186 285 371 367 REF 2008h 167 236 346 384 REF 2009 216 294 335 377 MNS 1971-78a 134 257 325 376 MNS 1993b 176 256 316 334 MNS 1 9 9 4b 169 256 298 347 MNS 2003c 197 315 248 389 MNS 2 0 0 4d 170 276 335 370 MNS 20050 136 342 359 429 MNS 2006' 169 308 361 402 MNS 20079 355 402 433 MNS 2008h 81 399 364 MNS 2009 184 265 326 350 8 Siler 1981; b Duke Power unpublished data; C Duke Power 2004; d Duke Power 2005; e Duke Energy 2006; f Duke Energy 2007; 9 Duke Energy 2008; t Duke Energy 2009 5-10
Table 5-4. Striped bass mortalities observed in Lake Norman during weekly July and August surveys. No mortalities were observed Jul 10, 31 or Aug 13, 21, 24.
Date No.
Zone Mean TL (mm)
Jul 17 2
1 595 Jul 22 1
4 478 Jul 30 1
1 539 Aug 3 165 1
537 Aug 4 89 1
531 Aug 5 56 1
525 Aug 6 39 1
523 Aug 7 9
1 Total 362 531 Table 5-5.
Lake Norman forage fish densities (No./ha) and population September 2009 hydroacoustic survey.
estimates from Zone 1
2 3
4 5
6 No./ha 3,068 3,867 5,124 5,201 20,706 20,706a Population estimate 6,998,295 11,918,918 17,704,647 6,402,898 43,607,611 9,897,644 Lakewide total 96,530,013 95% Cl 73,328,424 - 119,731,602 a Zone 6 fish density was assumed to be the same as Zone 5 5-11
Table 5-6. Number of individuals (No.), percent composition of forage fish, and threadfin shad modal TL class collected from purse seine surveys in Lake Norman during late summer/fall, 1993 - 2009.
Species composition Threadflin shad modal Year No.
Threadfin shad Gizzard shad Alewife TL class (mm) 1993 13,063 100.00%
31-35 1994 1,619 99.94%
0.06%
36-40 1995 4,389 99.95%
0.05%
31-35 1996 4,465 100.00%
41-45 1997 6,711 99.99%
0.01%
41-45 1998 5,723 99.95%
0.05%
41-45 1999 5,404 99.26%
0.26%
0.48%
36-40 2000 4,265 87.40%
0.22%
12.37%
51-55 2001 9,652 76.47%
0.01%
23.52%
56-60 2002 10,134 74.96%
25.04%
41-45 2003 33,660 82.59%
0.14%
17.27%
46-50 2004 21,158 86.55%
0.24%
13.20%
51-55 2005 23,147 98.10%
1.90%
36-45 2006 14,823 94.87%
5.13%
41-45 2007 27,169 98.34%
1.66%
41-45 2008 47,586 95.58%
4.42%
41-45 2009 16,380 88.40%
11.60%
46-50 5-12
Purse seine locations Electrofishing transects 5
Zone 4 00Z51 2
3
- 00. 1 2
3 0
1 2
Ms Cowans Ford Dam Kilometers McGulre Nuclear Station Figure 5-1.
Sampling locations and zones associated with fishery assessments in Lake Norman.
5-13
3500 3000 0 MNS 2500 E
C 2000 0
- . 1500 1000 500 0
+9
.÷~
- 0) 0-W r--
W 0M
- 0)
CO0 0a 0>)
0 0
0 0
0
- 0)
- 0)
- 0)
- 0)
- 0)
- 0) 0 0*
0 0
0 0
0 0*
0 0
1-4-
1 N
¢ N
N 4
N 4
N 1
IN CN Year 200 2 MSS 387 180 EREF b
160 0JMNS 140 o
120 100 x:
80 80 L-60 40 20 a)
- 0)
- 0)
- 0)
- 0)
- 0) 0 0
0 0
0 0
0 0
0 0
Year Figure 5-2. Number of individuals (a) and biomass (b) of fish collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, March/April 1993 - 1997 and 1999 - 2009.
5-14
200 a
200
- S
-- /
MSS 180 GREF 160 4OMNS E
140 0C)
V 120 0z
--- 100 a80 60 40 20 0
-4 2001 2002 2003 2004 2005 2006 2007 2008 2009 Year 30
- MSS EREF 25 OMNS b
0020
~15 S10 0
5 0
--I 2009 2001 2002 2003 2004 2005 2006 2007 2008 Year Figure 5-3.
Number of individuals (a) and biomass (b) of spotted bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, March/April 2001 - 2009.
5-15
70" 101
- MSS E REF 0 MNS a
60 E
~40 30 20 nU 10 0
15-199 20024 250-29 3
9 3-39940 0
91 I 150-199 200-249 250-299 300-349 350-399 400-449
- !450
<150 TL class (mm) 16 T 14 +
- MSS
- REF OMNS b
E 0Z to 0
EU 12 t 10-8+
4+
2+4
<150 0 -
150-199 200-249 250-299 300-349 350-399 400-449
->450 TL class (mm)
Figure 5-4.
Size distributions of spotted bass (a) and largemouth bass (b) collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, April 2009.
5-16
85 T a
- REF OMNS 80 +
F C
E 0
75.
F 70 f 65-1 100-149 150-199 200-249 250-299 300-349 350-399 400-449 60
?450 TL class (mm) 95 T
- MSS
- REF OMNS 90 +
85 +
C E
-0
.0 Ew, FJ F-80 +
b 75 +
70 -
65 f 60 -
I i 150-199 200-249 250-299 300-349 350-399 400-449 2450 TL class (mm)
Figure 5-5.
Condition (Wr) for spotted bass (a) and largemouth bass (b) collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, April 2009.
5-17
300 OMSS a
250 E
200 0
M* 150 0E 100 50 z
50 70 60
.I.LLLL C14 CV C1 CV N
N N
N N
V C (4 Year E
0° 50 40 S30O 0E 2m 20
-J 10 0
Figure 5-6.
(M a)
M)
M)
C>
0 a
0 0
0 0
0 0
0 0
-I
-1
-1
-i-N N
N N
N*
N1 N*
Year Number of individuals (a) and biomass (b) of largemouth bass collected from electrofishing ten 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, March/April 1993 - 1997 and 1999 - 2009.
5-18
300 U Spotted bass 250 E
0
- z 200 0
150 100 I
, Largemouth bass OHybrid bass 0 ILL1 0
2005 2006 2007 2008 2009 Year Figure 5-7. Number of young-of-year black bass (< 150 mm) collected from electrofishing five 300-m transects each, at three areas (MSS, REF, MNS) in Lake Norman, November 2005 - 2009.
700 650
-. 600 E
550 500 450 400 Mean Wr
-*- Mean Tl 95 90 85 80 9 CD 75 70 65 60 1
2 3
4 5
Age (years) 6 7
8 9
Figure 5-8.
Mean TL and condition (Wr) by age of striped bass collected in Lake Norman, December 2009. Numbers of fish by age are inside bars.
5-19
120
-U-Zone Zone2 Zone 3
-e-Zone4
-..-- Zone 5 Zone 6 Lakewide 100 o
80
.2o E
C._
6 60 Z
0 CU 20 0
Figure 5-9.
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Year Zonal and lake-wide population estimates of pelagic forage fish in Lake Norman, September 1997 - 2009.
400 T *Threadfin shad 0 Alewife 350 t-300 t 0
(D 0
(U 250 t 200 +
150 +
100 t 50 0
.1,I.1 I,
0 U
0 U
0 U
0 U
OLD 0
U, 0
U, 0
TL class (mm)
A Figure 5-10.
Number of individuals and size distribution of threadfin shad and alewife collected from purse seine surveys in Lake Norman, September 2009.
5-20
LITERATURE CITED American Public Health Association (APHA). 1995. Standard Methods for the Examination of Water and Wastewater. 19th Edition. APHA. Washington, DC.
Analytical Software. 2008. Statistix 9. Analytical Software. Tallahassee, FL.
Anderson, RA and RM Neumann. 1996. Length, weight, and associated structural indices.
Pages 447-482 in BR Murphy and DW Willis, editors.
Fisheries Techniques.
American Fisheries Society. Bethesda, MD.
Brandt, SB. 1996. Acoustic assessment of fish abundance and distribution. Pages 385-432 in BR Murphy and DW Willis, editors. Fisheries Techniques. American Fisheries Society. Bethesda, MD.
Buynak, GL, LE Kornman, A Surmont, and B Mitchell. 1989. Longitudinal differences in electrofishing catch rates and angler catches of black bass in Cave Run Lake, Kentucky. North American Journal of Fisheries Management. 9:226-230.
Cole, TM and HH Hannan. 1985. Dissolved oxygen dynamics. in Reservoir Limnology:
Ecological Perspectives. KW Thornton, BL Kimmel and FE Payne, editors. John Wiley & Sons, Inc. New York, NY.
Coutant, CC.
1985.
Striped bass, temperature, and dissolved oxygen: A speculative hypothesis for environmental risk. Transactions of the American Fisheries Society.
114:31-61.
Derwort, JE. 1982. Periphyton. Pages 279-314 in JE Hogan and WD Adair, editors. Lake Norman Summary, Volume II. Duke Power Company, Technical Report DUKE PWR/82-02. Duke Power Company, Production Support Department, Production Environmental Services. Huntersville, NC.
Devries, DR and RV Frie. 1996. Determination of age and growth. Pages 483-512 in BR Murphy and DW Willis, editors. Fisheries Techniques. American Fisheries Society.
Bethesda, MD.
Duke Energy. 2006.
Lake Norman maintenance monitoring program:
2005 summary.
Duke Energy Corporation, Charlotte, NC.
Duke Energy. 2007.
Lake Norman maintenance monitoring program:
2006 summary.
Duke Energy Corporation, Charlotte, NC.
Duke Energy.
2008.
Lake Norman maintenance monitoring program:
2007 summary.
Duke Energy Corporation, Charlotte, NC.
L-1
Duke Energy. 2009.
Lake Norman maintenance monitoring program:
2008 summary.
Duke Energy Corporation, Charlotte, NC.
Duke Power. 1997. Lake Norman maintenance monitoring program.
Energy Corporation. Charlotte, NC.
Duke Power. 1998. Lake Norman maintenance monitoring program:
Energy Corporation. Charlotte, NC.
Duke Power. 1999. Lake Norman maintenance monitoring program:
Energy Corporation. Charlotte, NC.
Duke Power. 2000. Lake Norman maintenance monitoring program:
Energy Corporation. Charlotte, NC.
Duke Power. 2001. Lake Norman maintenance monitoring program:
Energy Corporation. Charlotte, NC.
Duke Power. 2002. Lake Norman maintenance monitoring program:
Energy Corporation. Charlotte, NC.
Duke Power. 2003. Lake Norman maintenance monitoring program:
Energy Corporation. Charlotte, NC.
1996 summary.
1997 summary.
1998 summary.
1999 summary.
2000 summary.
2001 summary.
2002 summary.
Duke Duke Duke Duke Duke Duke Duke Duke Duke Duke Duke Duke Duke Duke Power. 2004a. Lake Norman maintenance monitoring program:
2003 summary.
Duke Energy Corporation. Charlotte, NC.
Power. 2004b. McGuire Nuclear Station. Updated Final Safety Analysis Report.
Duke Energy Corporation. Charlotte, NC.
Power. 2005. Lake Norman maintenance monitoring program: 2004 summary. Duke Energy Corporation. Charlotte, NC.
Power Company. 1976. McGuire Nuclear Station, Units 1 and 2, Environmental Report, Operating License Stage.
6th rev. Volume 2.
Duke Power Company.
Charlotte, NC.
Power Company.
1985.
McGuire Nuclear Station, 316(a) Demonstration.
Duke Power Company. Charlotte, NC.
Power Company.
1987.
Lake Norman maintenance monitoring program: 1986 summary. Duke Power Company. Charlotte, NC.
Power Company.
1988.
Lake Norman maintenance monitoring program:
1987 Summary. Duke Power Company, Charlotte, NC.
L-2
Duke Power Company.
1989.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1990.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1991.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1992.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1993.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1994.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1995.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
Duke Power Company.
1996.
Lake Norman maintenance summary. Duke Power Company, Charlotte, NC.
monitoring program:
monitoring program:
monitoring program:
monitoring program:
monitoring program:
monitoring program:
monitoring program:
monitoring program:
1988 1989 1990 1991 1992 1993 1994 1995 Ford, DE. 1987. Mixing processes in DeGray Reservoir. in Proceedings of the DeGray Lake Symposium. RH Kennedy and J Nix (editors). USACE Technical Report E87-4.
Hamme, RE. 1982. Zooplankton. Pages 323-353 in JE Hogan and WD Adair, editors. Lake Norman Summary, Technical Report DUKEPWR/82-02.
Duke Power Company.
Charlotte, NC.
Hannan, HH, IR Fuchs, and DC Whittenburg.
1979.
Spatial and temporal patterns of temperature, alkalinity, dissolved oxygen and conductivity in an oligo-mesotrophic, deep-storage reservoir in Central Texas. Hydrobiologia. 51 (30):209-221.
Hayes, DB, CP Ferrier, and WW Taylor. 1996. Active fish capture methods. Pages 193-220 in BR Murphy and DW Willis, editors. Fisheries Techniques. American Fisheries Society. Bethesda, MD.
Higgins, JM and BR Kim.
1981.
Phosphorus retention models for Tennessee Valley Authority reservoirs. Water Resources Research. 17:571-576.
L-3
Higgins, JM, WL Poppe, and ML Iwanski. 1980. Eutrophication analysis of TVA reservoirs.
Pages 412-423 in Surface Water Impoundments.
HG Stefan, editor. American Society of Civil Engineers. New York, NY.
Home, AJ, and CR Goldman. 1994. Limnology, 2nd Ed. McGraw-Hill, Inc. 525 pp.
Hutchinson, GE 1938.
Chemical stratification and lake morphometry.
Proceedings of National Academy of Sciences. 24:63-69.
Hutchinson, GE 1957.
A Treatise on Limnology. Volume I. Geography, Physics and Chemistry. John Wiley & Sons, Inc. New York, NY.
Hutchinson, GE. 1967. A Treatise on Limnology. Volume II. Introduction to Lake Biology and the Limnoplankton. John Wiley & Sons, Inc. New York, NY.
Hydrolab Corporation. 2006. Hydrolab DS5X, DS5 and MS5 water quality multiprobes.
Users manual. February 2006, Edition 3.
Kohler, CC and JJ Ney. 1980. Piscivority in a land-locked alewife (Alosa pseudoharengus) population. Canadian Journal of Fisheries and Aquatic Sciences. 37:1314-1317.
Maceina, MJ and DR Bayne. 2001. Changes in the black bass community and fishery with oligotrophication in West Point Reservoir, Georgia.
North American Journal of Fisheries Management. 21:745-755.
Madenjian, CP, RL Knight, MT Bur, and JL Forney. 2000. Reduction in recruitment of white bass in Lake Erie after invasion of white perch. Transactions of the American Fisheries Society. 129:1340-1353.
Matthews, WJ, LG Hill, DR Edds, and FP Gelwick. 1985. Influence of water quality and season on habitat use by striped bass in a large southwestern reservoir. Transactions of the American Fisheries Society. 118:243-250.
Menhinick, EF and LD Jensen.
1974.
Plankton populations.
Pages 120-138 in Environmental Responses to Thermal Discharges from Marshall Steam Station, Lake Norman, North Carolina.
LD Jensen, editor. Electric Power Research Institute, Cooling Water Discharge Research Project (RP-49) Report No. 11. Johns Hopkins University. Baltimore, MD.
Mortimer, CH. 1941. The exchange of dissolved substances between mud and water in lakes (Parts I and 1I). Ecology. 29:280-329.
Nelson, C, and L Dorsey. 2005. Population characteristics of black crappies in Lake Norman 2004. Survey Report, Federal Aid in Fish Restoration Project F-23-S. North Carolina Wildlife Resources Commission. Raleigh, NC.
L-4
North Carolina Department of Environment, Health, and Natural Resources (NCDEHNR).
1991.
1990 Algal Bloom Report. Division of Environmental Management (DEM),
Water Quality Section.
North Carolina Department of Environment and Natural Resources (NCDENR). 2004. Red Book. Surface Waters and Wetland Standards. NC Administrative Code. 15a NCAC 02B.0100,.0200 and.0300. August 1, 2004.
NCDENR. 2008. Catawba river basin ambient monitoring system report. December 2008.
NCDENR. 2010. Catawba river basinwide water quality plan. September 2010.
Petts, GE. 1984. Impounded Rivers: Perspectives for ecological management. John Wiley
& Sons, Inc. New York, NY.
Rodriguez, MS. 1982. Phytoplankton. Pages 154-260 in Lake Norman summary. JE Hogan and WD Adair, editors.
Technical Report DUKEPWR/82-02.
Duke Power Company. Charlotte, NC.
Siler, JR. 1981.
Growth of largemouth bass, bluegill, and yellow perch. in Lake Norman, North Carolina - A summary of 1975 through 1979 collections. Research Report PES/81-6. Duke Power Company. Huntersville, NC.
Siler, JR, WJ Foris, and MC McInerny.
1986.
Spatial heterogeneity in fish parameters within a reservoir. Pages 122-136 in Fisheries Management: Strategies for the 80's.
GE Hall and MJ Van Den Avyle, editors. Reservoir Reservoir Committee, Southern Division American Fisheries Society. Bethesda, MD.
Soballe, DM, BL Kimmel, RH Kennedy, and RF Gaugish.
1992.
Reservoirs.
in Biodiversity of the southeastern United States aquatic communities. John Wiley &
Sons, Inc. New York, NY.
Stumm, W and JJ Morgan.
1970.
Aquatic Chemistry: An Introduction Emphasizing Chemical Equilibria in Natural Waters. John Wiley & Sons, Inc. New York, NY.
Thornton, KW, BL Kimmel, and FE Payne, editors. 1990. Reservoir Limnology: Ecological Perspectives. John Wiley & Sons, Inc. New York, NY.
U.S. Environmental Protection Agency (USEPA). 1983. Methods for the Chemical Analysis of Water and Wastes.
Environmental Monitoring and Support Lab, Office of Research and Development. Cincinnati, OH.
USEPA. 1998a. Quality assurance project plans. Technical Report. EPA QA/G-5.
USEPA.
1998b. EPA requirements for quality assurance project plans for environmental data. Technical Report. EPA QA/R-5.
L-5
United States Geological Survey (USGS). 1998. National field manual for the collection of water quality data. United States Geological Survey. TWRI Book 9.
USGS. 2002. Policy for the evaluation and approval of analytical laboratories. Office of Water Quality. Technical Memoranda 2002.05.
Wetzel, RG. 1975. Limnology. WB Saunders Company. Philadelphia, PA.
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