ML20003G987
| ML20003G987 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 03/31/1981 |
| From: | Jason White VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | |
| Shared Package | |
| ML20003G985 | List: |
| References | |
| NUDOCS 8105040425 | |
| Download: ML20003G987 (165) | |
Text
.. -. - _ .
O ENVIRONMENTAL STUDY OF
~ LAKE ANNA, VIRGINIA ANNUAL REPORT
, January 1, 1980 - December 31, 1980 1
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' Prepared for:
[}
THE VIRGINIA ELECTRIC AND POWER COMPANY j
Prepared by:
l James R. Reed and Associates, Inc. ,
Environmental Testing and Consulting 813 Forrest Drive :
Newport News, Virgina 23606 ,
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March 31, 1981
.(]) l 81050.40 Nf ;
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ENVIRONMENTAL STUDY OF LAKE ANNA, VIRGINIA ANNUAL REPORT January 1, 1980 - December 31, 1980 TABLE OF CONTENTS t Page Table of Contents ii List of Tables y List of Figures vii Acknowledgements viii
() General Introduction ix Summary 0-1 Chapter 1 Heavy Metals and Nutrients 1.1 Introduction 1-1 1.2 Methods and Materials 1-2 1.E.1 Heavy Metals 1-2
- . 1.2.2 Nutrients 1-4
! 1.2.3 Station Descriptions 1-6 1.3 Results 1-8 1.3.1 Heavy Metals 1-8 1.3.2 Nutrients 1-13 1.3.2.1 Nitrate Nitrogen 1-13 1.3.2.2 Ammonia Nitrogen 1-14 1.3.2.3 Phosphate 1-14 1.3.2.4 Sulfate 1-15 1.4 Summary 1-18 1.5 References 1-20 Chapter 2 Chlorophyll, Primary Productivity and l
Temperature Studies l
2.1 Introduction 2-1
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Page 2.2 Methods and Materials 2-1 2.2.1 Chlorophyll 2-1 2.2.2 Primary Productivity 2-3 2.2.3 Statistical Analyses 2-6 2.3 Results and Discussion 2-6 2.3.1 Chlorophyll 2-6 2.3.2 Primary' Productivity 2-6 2.3.3 Temperature 2-13 2.4 Summary 2-13 2.4.1 Chlorophyll 2-13 2.4.2 Primary Productivity 2-13 2.4.3 Temperature 2-14 2.5 References 2-15 .
Chapter 3 Phytoplankton Studies 3.1 3-1 Introduction 3.2 Methods and Materials 3-1 3.3 Results and Discussion 3-3 3.4 Summary 3-6 3.5 References 3-13 .
() Chapter 4 Zooplankton Studies 4.1 Introduction 4-1 4.2 Materials and Methods 4-1 4.3 Results and Discussion 4-3 4.4 Summary 4 10 4.5 References 4-13 Chapter 5 Macrobenthos 5.1 Introduction 5-1 5.2 Methods 5-1 5.3 Resul ts 5-5 5.3.1 Sample Collection 5-5 5.3.2 Density and Percentage Composition 5-6 5.3.3 Diversity 5-17 5.3.4 Horizontal Distribution 5-17 5.3.5 Vertical Distribution 5-17 5.3.6 Surface Community 5-21 5.4 Summary 5-21 5.5 References 5-22 Chapter 6 Fish Studies 6.1 Introduction 6-1
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O Page 6.2 Methods 6-1 6.2.1 Fish Collection Techniques and Station Designations 6-1 6.2.2 Water Quality Analyses 6-4 6.2.3 Abundance and Distribution of Populations 6-5 6.2.4 Age and Growth of Largemouth Bass 6-5 6.3 Results 6-7 6.3.1 Physical and Chemical 6-7 i 6.3.2 Relative Abundance Based on Gill Net Observations 6-7 6.3.3 Cove Rotenone Studies 6-29 6.3.4 Gonosomatic Index of the Female, Micropterus salmoides 6-44 '
6.3.5 Age and Growth of the Largemouth Bass, Micropterus salmoides 6-46 6.3.6 Food Habits of the Largemouth Bass, Micropterus salmoides 6-47 6.4 Summary 6-53 6.4.1 Physical and Chemical 6-53 Relative Abundance Based on Gill Net i 6.4.2 i Observations 6-53 Cove Rotenone 6-54 Q- 6.4.3 v 6.4.4 Gonosomatic Index of the female, Micropterus salmoides 6-54 6.4.5 Age and Growth of the Largemouth Bass, Micropterus salmoides 6-55 6.4.6 Food Habits of the Largemouth Bass, Micropterus salmoides 6-55 6.4.7 Fish Species 6-55 6.5 References 6-58 I
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O LIST OF TABLES Number Page 1.2.1.1 Average Detection Limits for Heavy Metals
< in Lake Antia Water Samples 1980. 1-2 1.2.2.1 Nutrient Methodology. 1-4 1.2.2.2 Average Detection Limits for Nutrients 1-4 1.3.1.1 A Comparison of Mean Heavy Levels in Lake Anna Water from 1975-1980. 1-10 1.3.2.1 A Comparison of Mean Anton Levels in Lake Anna Water 1975-1980. 1-16 2.2.2.1 Analytical Procedure for Determination of Water Quality Parameters at Productivity Stations. 2-7 2.3.1.1 Comparison of Mean Quarterly Chlorophyll a -
Values (mg/m3). 2-8
(]) 2-9 4 2.3.1.2 A Ranking of Mean Chlorophyll a Values.
2.3.2.1 Tukey's w-procedure Test of Primary 2-10 Productivity Data, Date by Station.
Mean Primary Productivity Values. 2-11 2.3.2.2 3.3.1 Tukey's w-procedure Test of Phytoplankton 3-4 Data, Date by Station.
3.3.2 Phytoplankton Taxa and Corresponding Unit 3-7 Volumes.
4.3.1 Tukey's w-procedure Test of Zooplankton 4-4 j Data, Date by Station.
4.3.2 Relative Abundance Ranking of Zooplankton Density by Month. 4-6 4.3.3 Relative Abundance Ranking of Zooplankton Density by Station. 4-7 Zooplankton Master List. 4-11 4.3.4 O
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Number page 5.3.2.1 Taxonomic List of Macrobenthic Organisms Collected. 5-7 5.3.2.2 Density and Percentage Composition of Dominant Macrobenthos During 1980 5-11 5.3.4.1 Horizontal Distribution of Dominant Macrobenthos. 5-18 5.3.5.1 '!ertical Distribution of Dominant Macrobenthos. 5-20 ,
6.3.2.1 Catch Per Net Day in Number of Individuals by Species, 1973-1980. 6-8 i
( 6.3.2.2 Catch Per Net Day as Expressed by Weight,
! 1975-1980. 5-19 I 6.3.2.3 Total Catch Per Net Day Expressed as
() Numbers of Individuals, 1973-1980. 6-30 6.3.2.4 . Total Catch Per Net Day Expressed as Weight, 1975-1980. 6-31 i 6.3.3.1 Fish Standing Crop Estimates Based Upon Cove Rotenone Samples by Species 6-32 l
6.3.4.1 Gonosomatic Index (%) of the Female Largemcuth Bass in Lake Anna, 1980 6-45 6.3.5.1 Back Calculated Length Attained by Each Year Class of Largemouth Bass (Lower Reservoir, 1980). 6-48 6.3.5.2 Back Calculated Length Attained by Each Year Class of Largemouth Bass (WHTF, 1980). 6-50
- 6.3.6.1 Gut Content of the Largemouth Bass in
- Lake Anna, 1980. 6-52 6.4.7.1 Fish Species List. 6-56 i
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LIST OF FIGURES Number Page 4
1.2.1.1 Approximate Location of Sampling Statinns for Heavy Meta's. 1-3 1.2.2.1 Nutrient Sampling Locations. 1-5 2.2.1.1 General Location of Chlorophyll Sampling Stations. 2-2 2.2.2.1 General Location of Primary Productivity Sampling Stations. 2-4 .
3.2.1 General Location of Phytoplankton Sampling Stations. 3-2 42 !
f 4.2.1.1 Zooplankton Sampling Stations. 1 1
! 5.2.1 Location of Macroinvertebrate Stations. 5-2 !
Diagram of Typical Benthic Staticn. 5-4 j
(]) 5.2.2 6-2 6.2.1.1 General Location of Gill Netting Stations.
I General Location of Rotenone Stations. 6-3 6.2.1.2 I
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ACKNOWLEDGMENT James R. Reed and Associates, Inc. would like to acknowledge the support of the following organizations in the completion of this project: Virginia Coramission of Game and Inland Fisheries, Virginia State Water Control Board and the Virginia Electric and Power Company at the North Anna Power Station for their cooperation in all phases of the study. .
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GENERAL INTRODUCTION Lake Anna Reservoir with a surface area of approximately 3.24 x 104 hectares is utilized to provide cooling water for the Virginia Electric and Power Company's second nuclear facility, the North Anna Power Station. It is divided into a waste heat treatment system which comprises 8.4 x 10 3 hectares and the main Reservoir containing 2.4 x 10 4 hectares. .
To avoid confusion, the following terminology will be used to refer to the different, or collective, water bodies:
Lake Anna - Both reservoirs or the entire project; Reservoir - Main body of Lake Anna; Upper Reservoir - Lake above Rt. 208 bridge;
{) Lower Reservoir - Lake below Rt. 208 bridge; Waste Heat Treatment Facility (WHTF) - Lagoon complex the smaller reservoir or lagoons.
Sampling dates associated with plankton and productiv'ity
- data use 3 letter abbreviations for the corresponding month (i.e. JAN, FEB, MAR). JUN1 and JUN2 denote the first and second samplings within the month of June.
The Reservoir and WHTF were filled from separate drainage basins. Very little mixing has occurred between waters of the WHTF and of the Reservoir due to earthen dikes between them.
In addition, the area of the WHTF was not directly subjected to acid and metal mine drainage from Contrary Creek, a site of pyrite mining until the 1920's.
This study summarizes the ecological and water quality studies carried sut from January 1, 1980 through December 31, 1980 and is intended to supplement previous Virginia Electric and Power Company Preoperational Environmental Reports. ,
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SUMMARY
0.1 Heavy Metals and Nutrients Studies
- 1. Operation of the North Anna Power Station did not adversely affect water quality in Lake Anna in 1980.
- 2. The Contrary Creek area continues to show the influence of acid mine drainage and tailing deposits. Heavy metals concentrations are greater and pH 1evels are low-er in that region of Lake Anna than in other areas.
({) 1979 data. Iron concentrations are greater in hypolim-netic water than at other depths.
- 4. Iron was detected in only 33% of the September water samples and was totally absent in September WHTF samples..
- 5. In 1980 only 35% of the iron values recorded in Lake Anna exceeded the Virg. inia State Water Control Board drinking water reference level of 0.3 mg/l compared to 58% in 1979.
- 6. Copper occurred in 15% of the samples analyzed snd was absent in September and December samples. Most of the copper detected occurred in June samples.
- 7. Zinc levels were similar to those noted in 1979. As in previous years, the Contrary Creek stations, especially station 222, exhibited the highest zinc concentrations and zinc occurred most frequently in water samples from that area.
Quantities and distribution patterns of lead in 1980 were similar to those noted in 1979.
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- 9. High lead values reported in 1979 for the 4th quarter (December, 1979) sampling period are attributed to sample container contamination, based upon 1980 results.
- 10. Nitrate nitrogen increased in concentration in areas under the greatest influence of the North Anna Power Station. December values were greater at all stations than in 1979. No adverse effects of increased nitrate levels in Lake Anna were noted in 1980.
- 11. Ammonia nitrogen was low in 1980, following a trend of declining concentrations since 1975. The Upper Reservoir 1xhibited the highest ammonia levels in 1980 and as in
- previous years, the hypolimnetic wa'er contained more ammonia than water at other depths.
- 12. Total phosphorus declined in Lake Anna in 1980. Highest levels were detected in June and December, while March samples contained the lowest concentrations of phosphate.
The Upper Reservoir and Contrary Creek phosphorus levels were higher than other areas of Lake Anna. No ortho-phosphate (soluble inorganic' phosphate) was detected in O 1980.
- 13. The sulfate concentration in Lake Anna water in 1980 was similar to that recorded in 1979. The Upper Reservoir contained the lowest sulfate levels while the WHTF and Lower Reservoir were higher. As in previous years, Contrary Creek exhibited the highest sulfate concentra-tion especially in the spring due to acid mine drainage
- and runoff from fron pyrite deposits.
0.2 Chlorophyll, Primary Productivity and Temperature Studies Chlorophyll
- 1. The two Upper Reservoir stations (211 and 212) showed the highest levels of chlorophyll in 1900, particularly sta-tion 211. This was also the case in 1979.
- 2. Mean chlorophyll values for the four quarters of 1980 showed the 1st, 2nd and 3rd quarters to be significantly higher than the 4th quarter.
Primary Productivity f 1. The JUL2 and SEP samplings were the only dates to show a significant difference between stations.
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- 2. SamplinginthemontgofOctobershowedthehighest mean value for mgC/m /hr for the year.
Temperature
, 1. Station 111 showed higher temperatures than other sta-
- tions during the cooler months, which is a result of being located directly downstream from the reactors discharge canal.
- 2. Comparisons of the stations showed relatively little difference in mean temperature values. This was also the case in 1978 and 1979.
0.3 Phytoplankton Studies
- l. Station 221 had the highest mean density of the
- phytoplankton stations during 1980.
- 2. Bacillariophyta (diatoms) appeared to dominate the phyto-plankton community in the spring. Chlorophyta (green algae) was the next dominant group in the late spring /
early summer followed by Cyanophyta (blue green algae)
O in the late summer / autumn.
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- 3. This pattern of diatoms-greens-bluegreens is a typical successional series for temperate lakes.
- 0.4 Zooplankton Studies Characteristics that occurred in Lake Anna zooplankton in both 1978, 1979 and 1980
- 1. Stations 211, 212 and 221 had the highest mean densities of zooplankton.
- 2. Rotifera were numerically dominant.
- 3. Stations 223 and 111 showed consistantly lower numbers of zooplankton compared to other stations.
0.5 Macrobenthos Studies
- 1. The macrobenthos density did not show any significant increase during 1980 (Student T-Test o' =.05).
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'2. The actual numbers of organisms collected in 1980 in-creased over 1979 by a factor of 2.5, primarily due to increased numbers of Corbiculidae.
- 3. Corbicula became the dominant macroinvertebrate in the Lake in 1980 although it's increase occurred primarily in the WHTF.
- 4. The Ephemeroptera population declined slightly in 1980.
- 5. Isopoda continued to increase in numbers in 1980.
0.6 Fish Studies .
Physical and Chemical
- 1. Dissolved oxygen values were generally high throughout
- the water column at all fish stations for 1980.
- 2. Turbidity values for the Upper Reservoir fish stations, were higher than all other sampling stations.
I Relatite Abundance Based on Gill Net Observations
- 1. The gizzard shad increased in gill net catches since its appearance from 3.1 and 7.5% to as much as 68% of the total catch. A gradual decline in relative abundance of shad was noted in recent years, but 1980 showed an in-crease in shad standing crop.
- 2. The chain pickerel has suffered a decline in numbers j
throughout the study.
- 3. The carp has displayed an increase in catch per day as well as kg per net day, but during 1980 a decrease was noted in catch per net day.
- 4. The creek chubsucker has declined steadily in relative abundance throughout the study period.
- 5. The brown bullhead and the yellow bullhead have shown a decrease in catch per unit effort during the study perfsd.
! 6. The channel catfish has shown an increase in catch per
. unit effort.
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- 7. The largemouth bass displayed a decrease in relative abundance in Lake Anna compared to 1979.
- 8. The white perch has shown a marked increase in relative abundance over the study period.
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- 9. The striped bass has shown an increase in catch per unit effort in the Lower Reservoir, however no striped bass were caught in the WHTF in 1980.
- 10. The WHTF produced lower values for kg of fish caught per net day than the other study areas in 1980 rev9rsing the trend shown in 1978 and 1979.
Cove Rotenone Studies
- l. The gizzard sh..' was the most important fish in terms of standing crop.
- 2. The Upper Reservoir displayed the highest value for stand-ing crop of gizzard shad.
- 3. The carp has increased in standing crop since 1979.
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- 4. The creek chubsucker was collected at more stations than other suckers, but this species remains on a steady decline.
- 5. The channel catfish has steadily increased.in standing crop over the past two years in the WHTF, but no channel catfish were collected in the WHTF during the 1980 rotenone sampling.
- 6. The white perch displayed an increase in standing crop during 1980.
- 7. Higher standing crop values were obtained from the Upper Reservoir in 1980 than for other areas of ',ake Anna as has historically been the case.
Gonosomatic Index of the female, Micropterus salmoides
- 1. During 1980, female bass at the Mid-Reservoir electro-fishing station displayed a peak gonad development in the third week of April, but female bass observed in the WHTF reached their peak gonad development during the first week of April.
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- 2. Female bass were observed in the " squeeze ripe" or spawning condition in the WHTF on April 10, 1980, where as the female bass collected in the Reservoir started spawning three weeks later on April 24, 1980.
Age and Growth of the largemouth Bass, Micropterus salmoides
- 1. The 1980 Lake Anna largemouth bass population was putting on more weight with length than the national average.
- 2. The age I largemouth bass in the WHTF grew significantly j faster than the first year bass in the other sampling ,
locations during 1979, but displayed no significant
, difference during 1980.
Food Habits of the Largemouth Bass, Micropterus salmoides
- 1. Throughout the study period from 1977-1980, it was evioent that the family Clupeidae, renresented by the single Q species, Dorosoma cepedianum, was the most frequently selected forage fish in the diet of the largemouth bass in Lake Anna.
- 2. The 1979-1980 operational years did not affect the food habits of the largemouth bass.
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O 1.0 Heavy Metals and Nutrients 1.1. Introduction As in the past, Lake Anna is defined in terms of four major areas. The Upper Reservoir represented
.by stations 211 and 212, is characterized by the relatively shallow arms (8 meters or less) of the North Anna River and '
Pamunkey Creek, both of which feed into the reservoir.
) Progressing down the reservoir, Contrary Creek is the next area to be encountered, represented by stations 221, 222, 223, 224, 225 and 231.
According to the Virginia State Water Control Board (1976), there are three now inactive pyrite mines and mining spoils piles that are contributing high concentrations of O dissolved metal and acid leachate to Contrary Creek, and ultimately to Lake Anna. The Board is developing a feasi-i l bility study to address the dissolved metals problem, and is using the EPA Demonstration Grant to reclaim the mine waste i areas'and abate the water quality problem.
' The Board speculates deleterious effects on the reser- '
voir's biotic components from significant concentrations of dissolved heavy metals and mentions the problems that could arise from the use of the reservoir as a thermal collector during power plant operations, but does not elaborate with any specific information in their 1976 Inventory Report. One warning made, however, regards massive uncontrolled develop-ment of the surrounding land, which could produce siltation problems, wastewater loadings, and water quality degradation 4
unless preventative steps are taken.
The Waste Heat Treatment Facility (WHTF) is on the re-ceiving end of the discharge canal from the North Anna Power Station and is represented by stations 111, 121, 131 and 132.
The Lower Reservoir, the furthest downstream point, is j represented by stations 241 and 243, where the waters from the WHTF return to the main body of the reservoir.
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The purpose of this sampling program was to provide enough data to characterize the existing water quality situation in Lake Anna and detect trends.
1.2 Methods and Materials 1.2.1 Heavy Metals Thirty-six water samples were collected quarterly from Lake Anna and the WHTF (Figure 1.2.1.1) dur-ing 1980 and analyzed for iron, copper, zine and lead. Sam-ples were drawn from three depths where possible: surface (epilimnion), middle (metalimnion) and bottom (hypolimnion).
Bottom samples were taken 1 meter from the bottom to avoid disturbing sediments which could give inaccurate readings for the metal content of the water column. Metalimnion sam-ples were not taken from stations 111, 131, 211, 212, 222 and 223 because the depths were less than 8 meters.
A non-metallic Hiskin water sampler (General Oceanics) was used in obtaining the samples, which were placed in acid-cleaned, sample-rinsed polyethylene bottles. A pH reading was taken to correspond with each metal sample, then the samples were volumetrically preserved with nitric acid, fil-tered through acid-cleaned filtering apparatus using 0.45
{sg/ micron filter membranes, and were returned to their original containers. Blank samples and standards w.ers prepared and carried through with each set of samples. An atomic absorp-tion spectrophotometer (Instrumentation Laboratories Model 251) was utilized for the analyses of iron, copper and zinc.
An attachment unit (Flameless Model 455) was also used for the detection of lead. The sample concentrations were calculated from the least-squares line of best fit of the standards for each analysis. Detection limits are given in Table 1.2.1.1. Values below detection limits are noted by the symbol ND. Values in Table 1.3.1.1 appearing to be less than detection limits are the rrsult of averaging.
l TABLE 1.2.1.1 AVERAGE DETECTION LIMITS FOR HEAVY METALS IN LAKE ANNA WATER SAMPLES IN 1980.
Detection Limits (ma/1)
Iron (Fe) 0.03 Copper (Cu) 0.03 Zinc (Zn) 0.01 Lead (Pb) 0.001 1-2 l
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l.2.2 Nutrients Water samples were collected quarterly in l conjunction with the metals samples and analyzed for ammonia nitrogen, nitrate nitrogen, total phosphate, orthophosphate, and sulfate. Samples were collected at four depths (0, 2, 4 and 6 meters) from the stations shown in Figure 1.2.2.1, yielding a total of 40 nutrient samples per collection. Sam-ples were placed into acid-cleaned, sample rinsed, brown polyethlene bottles. In the laboratory, duplicate samples were prepared for each analysis to insure accurate results, and were analysed according to the methods summarized in Table 1.2.2.1.
TABLE 1.2.2.1 NUTRIENT METHODOLOGY Analysis Method 1 Ammonia Nitrogen Phenate Method, p. 416 Nitrate Nitrogen Cadmium Reduction Method, p. 413 Total Phosphate Persulfate Digestion, p. 476 and 4 Ascorbic Acid Method, p. 481 W Orthophosphate Ascorbic Acid Method, p. 481 Metaphosphate Subtraction,p. 469 -
Sul f a te Turbidimetric Method, p. 496 I Standard Methods for the Examination of Water and Waste-water, 14th. Edition; 1976).
Detection limits are shown in Table 1.2.2.2.
TABLE 1.2.2.2 AVERAGE DETECTION LIMITS FOR NUTRIENTS IN LAKE ANNA WATER SAMPLES IN 1980 l
l Detection Limit (mg/1) i Ammonia (NH4 +) 0.01 l Total Phosphate (T-PO4) 0.01 Orthophosphate (0-P04 ) 0.01 i Nitrate (NO3 ) 0.01 l - Sulfate (504 ) 0.3 bq 1-4
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, Ammonia nitrogen was determined directly using the col-
! orimetric phenate method. Levels of ammonia were low and interferences few enough to eliminate the need for predistil-l' lation. Nitrate nitrogen was determined by reducing nitrate to nitrite through a column of amalgamated cadmium filings and measuring colorimetrically.
t Total phosphate (total filtrable and nonfiltrable phos-
[ phate) samples were treated with a mild persulfate- digestion i
to release all bound forms of phosphate to the liberated orthophosphate form, and were then determined colorimetrically using th.e Absorbic Acid Method. Orthophosphate (total filtr-able or dissolved phosphate) samples were filtered, and ~ the
- filtrates were retained for analysis by direct colorimetry. ,
Sulfate was measured by nephelometry, i.e. the absorb-ance of a barium sulfate suspension from which the natural turbidity of the sample was subtracted.
1.2.3 station Descriotion Station 243 is the furthest down-stream station on Lake Anna and is in the Old North Anna j river channel about 450 m (1500 f t) from the dam. The reser-voir at this point is approximately 2.1 km (1.3 mi) wide and l
Q 21~m (70 ft) deep in the channel, however deeper soundings have been recorded off the southwest corner of the dam at a
! quarry site. This station is located about 1.2 km (.8 mi) from the center of the dike at Rock Creek, and is approxi-mately 4.3 km (2.7 mi) downstream from station 241, nearly 8.8 km (5.5 mi) from the power station. This area is fairly exposed to wind conditions due to the lack of prominent shorelines.
Station 241 is located approximately halfway between the power station and the dam in the reservoir. It is 4.6 km (2.8 mi) from the power station, just downstream from Duke's Creek and about 230 m (750 ft) southwest of a point of shoro.
I The depth at this station is about 16 m (42 f t) and lies in j the original channel of the North Anna River.
Station 231 is located about 460 m (1500 ft) from the intakes to the power station in water approximately 8 m (25 ft) deep. The reservoir is almost 1.2 km (.8 mi) wide in this area. The mid-chanr:el depth at the power station is about 15 m (50 ft). This site is located just downstream from Sturgeon Creek.
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O Station 225 is locat'ed on the original channel of the North Anna River approximately 1.7 km (1.0 mi) upstream from Station 231. It is beneath power lines crossing the reservoir, off the southern shore about 38 m (125 ft). The depth of the water is 15 m (50 f t), and the span across the reservoir is about 300 m (1000 ft). It is approximately 1.2 km (.8 mi) downstream from Contrary Creek.
Station 224 is in the lower reaches of Contrary Creek, approximately .9 km (.6 mi) from the mouth. It is about 9 m (30 f t) from the northwest shore at the site of rock outcrop-pings. The depth here is 12 m (40 ft), located over the
. original creekbed, and the width of the impoundment is about 380 m (1250 ft).
Station 223 is midway between the Route 652 bridge over Contrary Creek and station 224, in an enlarged bay-like area, approximately 1.2 km (.8 mi) from each of these sites. The stations site is slightly off-center over the original creek-bed in water that is about 8 m (26 ft) deep. The width of this bay-like area is close to 610 m (2000 ft).
Station 222 is the uppermost station on Contrary Creek,
\ just downstream from the bridge crossing of Route 652. The
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~_ water is about 8 m (26 ft) deep, and impoundment reaches approximately 2.3 km (1.4 mi) upstream. Feshwater Creek empties into Contrary Creek upstream from Station 222 and could be diluting the effects of mine dumps along the creek-bed of Contrary Creek about 4.6 km (2.8 mi) upstream.
Station 221 is upstream from the mouth of Contrary Creek just below the Route 208 bridge on the original North Anna River channel in 15 m (50 ft) of water. Tha reservoir is approximately 1.1 km (.7 mi) wide at station 221. This is the approximate mid-point in the length of the reservoir, and is about 3.4 km (2.1 mi) upstream from the power station.
Station 221 is located approximately 10.5 km (6.5 mi) upstream from the power station, just below the Route 719 bridge on the North Anna arm of the reservoir. The depth of the water is about 7m (23 ft), and the width of the impound-ment-is around 300 m (1000 ft).
Station 212 is located just downstream from the Route 719 bridge crossing of the Pamunkey Creek arm of the reser-voir. The water is naarly 9 m (30 ft) deep and the area is about 115 m (375 ft) wide. This station is about the same distance from the power station as is station 211.
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Stations 111, 121, 131 and 132 are located in the Waste Heat Treatment Facility. Station 111 is located at the end of the discharge canal from the power station in the vicinity
- of ths original Sedges Creek channel. It is 1.4 km (.9 mi) from the discharge point at the reactor site. The water is approximately 8 m (26 ft) deep at this point and 300 m (1000 ft) wide.
Station 121 is approximately 300 m (1000 ft) from the dike on Elk Creek in water 18 m (60 f t) deep, and the width of the impoundment is .8 km (.5 mi). This station is 5.8 km (3.6 mi) from the power station discharge.
Station 131 is near the end of the third canal where it empties into Coleman Creek. The impoundment is constricted ,
here, approximately 300 m (1000 ft) wide and 7 m (23 ft) deep. A strong flow in the direction of the third dike per-sists when the station pumps are functioning. This station -
is about 10.1 km (6.3 mi) from the power station discharge point.
Station 132 is located 300 m (1000 ft) from the dike near the original Rock Creek basin. The water is 15 m (50 :
ft) deep and the distance from shore to shore is about .9 km 0 (.6 mi)'. This station is about 12.8 km (8.0 mi) from the power station discharge point. From this station, cooling i
water from the WHTF reenters the reservoir and may recircu-late up to the power station. The entire recirculation distance is approximately 22.0 km (13.6 mi). i 1.3 Results 1.3.1 Heavy Metals From 1979 to 1980 the overall water temperature taken during heavy metals sampling in Lake Anna increased approximately 1.5*C. The increase was largerly ,
attributable to a 7.94*C greater average value in September, !
1980 compared to the same period in 1979. This large in-crease offset a lower 1980 March temperature which was i 2.46*C less than 1979. Water temperatures were greater in ;
all areas of Lake Anna during 1980 than in 1979. The great- ;
est average increase (1.88 C) was recorded in Area 3 which i is comprised of the WHTF stations, while the smallest in- ,
crease in water temperature occurred in Area 2 which includes .
the Mid-Reservoir stations 221, 222, 223, 224, 225 and 231.
Station 111, nearest the discharge canal in the WHTF again l had the highest average temperatures, while staticos 211 and !
l 212 in the Upper Reservoir had the coolest water in Lake Anna l l
(Data Base). This pattern is similar to that observed in l
1979. f
, <s i
\-)
1-8 l l
l L
I
i LO Annual overall mean temperatures showed no stratifica-tion between the surface and six meters, however straticica-tion did occur at greater depths at some stations. Water 1 temperatures at the WHTF stations were generally more homoge-l neous in any sampling period due to mixing created by the
[
flow from the discharge canal.
The pH in Lake Anna was similar to that recorded in j 1979 with a few exceptions. The March 1980 overall mean pH i was 7.0, compared to 6.4 in March 1979. Only stations 222 and 223 in the Contrary Creek arm had average pH values less than 7.0 in March. Yearly pH averages at these stations were the lowest of all stations as well, 6.1 and 6.5 respec-tively and Station 222 again exhibited the lowest single pH value (5.3 in March). December 1980 pH samples were de-l
! stroyed in the laboratory and thus the 1980 pH data represents -
l only March, June and September numbers.
I Table 1.3.1.1 is a comparison of heavy metal levels in Lake Anna from 1975-1980 for all stations except stations 132, 223, 224 and 231 which were not included in the study until 1976.
The overaT1 iron concentration decreased in Lake Anna
-() in 1980, reaching historically 1cw levels at several stations.
The iron values were approximately one-third of those record-ed in the study area of Lake Anna in 1979 (Data Base). The
! Upper Reservoir exhibited the lowest iron levels, while the
! highest concentrations were obtained from stations 222 and l 223 in Contrary Creek. The single highest value (4.27 mg/1) was recorded from a 16 meter hypolimnetic sample at station 243 in December. A value of 3.54 mg/l was also obtained in December from a 6 meter bottom sample at station 223. High concentrations of iron were noted in 8 meter bottom samples at station 222 in March (1.97 mg/1), June (1.58 mg/1) and September (3.96 mg/1), following a pattern noted in 1979 for hypolimnetic samples in Lake Anna, and in Contrary Creek in pa rti'cul a r. It is interesting to note that iron was detect-ed in only 33% of the September samples and was totally absent in September WHTF samples but occurred commonly at all stations at other times of the year, as noted in pre-vious studies.
In 1980 only 35% of the iron ve. lues exceeded the Virginia State Water Control Board reference level of 0.3 mg/l for drinking water compared to 58% in 1979.
l Copper occurred in small quantities in Lake Anna water, in 1980 as noted previously. None was detected in Septe nber l
()
1-9
O TABLE 1.3.1.1 A COMPARISON OF MEAN HEAVY METAL LEVELS IN LAKE ANNA WATER FROM 1975-1980 FOR EACH STATION Fe Cu Zn Pb Station Year (mg/1) (mg/1) (mg/l) (mg/1) 3 111 1975 0.37 0.01 0.01 0.04 1976- 0.80
~
0.014 0.0 0.001 1977 0.53 0.0 0.0 0.0 1973 0.74 0.002 0.004 0.002 1979 0.38 0.0 0.0 0.0 1980 0.12 0.0 0.001 0.0002 121 1975 0.21 0.01 0.0 0.04 1976 0.39 0.007 0.001 0.002 1977 0.50 0.0 0.0 0.0 1978 0.14 0.0 0.0 0.0 1979 0.35 0.0 0.001 0.003 1980 0.14 0.005 0.003 ND 131 1975 0.33 0.01 0.01 0.07 1976 0.04 0.015 0.0 0.004 1977 0.94 0.0 0.0 0.0 1978 0.90 0.0 0.007 0.001 1979 0.60 0.0 0.0 0.0 1980 0.21 0.003 ND ND 132 1976 0.59 0.013 0.0 0.0 1977 0.82 '0.0 0.0 0.0 197S 0.33 0.001 0.004 0.002 1979 0.48 0.0 0.0 0.005 1980 0.17 0.005 0.015 0.0001 211 1975 2.17 0.01 0.0 0.03 1976 0.33 0.007 0.002 0.0 1977 0.45 0.0 0.001 0.0 1978 0.69 0.0 0.0 0.001 1979 1.33 0.0 0.0 0.001 1980 0.37 0.003 0.009 ND 212 1975 1.20 0.02 0.01 0.02 1976 0.30 0.009 0.003 0.0 1977 0.60 0.0 0.0 0.0 '
1978 0.56 0.0 0.0 0.001 1979 1.73 0.0 0.0 0.0
(~D 1980 0.34 ND ND U.0005 u) 1-10
. - ~ . -
4 l
O TABLE 1.3.1.1 (Continued) A COMPARIS0N OF MEAN HEAVY METAL LEVELS IN LAKE ANNA WATER FROM 1975-1980 FOR EACH STATION i
Cu Zn Pb Fe (mg/1)
(mg/1) (mg/1) (mg/1) ]
Station Year 0.01 0.02 0.04 221 1975 1.70 0.003 1976 0.70 0.021 0.0 0.0 0.0 0.0 1977 0.86 0.001 1978 0.42 0.001 0.003 0.0 0.016 0.001 1979 2.75 0.0002 1980 0.32 0.005 0.018 0.065 0.19 0.06 222 1975 1.59 0.0 1976 0.47 0.076 0.047 1.67 0.059 0.030 0.0 1977 0.182 0.007 1978 0.80 0.051 1.48 0.180 0.229 0.001 1979 0.186 0.009 1980 1.13 0.030 0.19 0.043 0.022 0.0 1976
(]) 223 1977 1.11 0.036 0.019 0.0 0.001 1978 0.60 0.005 0.012 3.39 0.026 0.162 0.006 1979 0.0020 1980 0.64 0.008 0.143 1.47 0.020 0.002 '0.0 224 1976 0.011 0.0 1977 1.82 0.027 0.93 0.037 0.132 0.005 1978 0.068 0.002 1979 1.51 0.002 0.33 0.008 0.165 0.0002 1980 1.63 0.01 0.02 0.09 225 1975 0.0 1976 1.02 0.012 0.0 0.77 0.005 0.0 0.0 1977 0.001 1978 0.52 0.004 0.0 0.0 0.009 0.001 1979 0.90 0.0033 1980 0.39 NO 0.013 0.05 0.0 0.0 231 1976 0.46 )
1977 0.0 0.002 l 1978 0.48 0.006 1 1979 0.62 0.0 0.002 0.0 1980 0.50 ND 0.008 ND O 1-11
O TABLE 1.3.1.1 (Continued) A COMPARISON OF MEAN HEAVY METAL LEVELS IN LAKE ANNA WATER FROM 1975-1980 FOR EACH STATION Fe Cu Zn Pb Station Year (mg/1) (mg/1) (mg/1) (mg/1) 241 1975 0.51 0.01 0.01 0.97 1976 0.76 0.042 0.0 0.0 1977 0.20 0.0 0.0 0.0 1978 0.91 0.001 0.0 0.001 1979 1.04 0.0 0.0 0.0 '
1980 0.26 0.003 0.013 0.0015 243 1975 0.75 0.03 0.02 0.94 1976 3.24 0.015 0.002 0.004 1977 0.23 0.0 0.0 0.0 1978 0.50 0.0 0.004 0.002 1979 0.57 0.001 0.001 0.0 1980 0.49 0.008 0.019 0.0003 4
1-12
O or December. Overall, copper was detected in approximately 15% of the samples, generally in the June sampling period.
The highest copper concentration (0.1 mg/1) occurred in a surface sample taken at station 222 in March. The only other sample in which copper was detected in March also came from station 222. None of the copper levels observed in 1980 Lake Anna water samples exceeded the 1.0 mg/l VSWCB -
(1976) reference level .
Zinc levels in 1980 Lake Anna samples were similar to those in 1979. March samples which were obtained from the Contrary Creek stations 221, 222, 223 and 225 contained the highest zine levels. As in previous studies, station 222 exhibited the highest levels of zinc throughout the year.
- The single highest concentration of zine (1.97 mg/1) was recorded from a 4 meter bottom sample at station 222 in March. Zinc occurred less frequently in September and December samples in Lake Anna and overall occurred in 34%
of the samples analyzed. As noted in 1979, zinc levels were higher in hypolimnetic water. None of the zinc values re-corded in 1980 exceeded the VSWCB (1976) reference levels of 5.0 mg/1.
() Lead continues to occur in Lake Anna in trace amounts.
Quantities and distribution patterns were similar to those noted in 1979. Lead was detected at the Contrary Creek stations during all sampling periods except December with the single highest value (0.01 mg/1) recorded from 6 meter bottom water at station 223 in September. Lead occurred in approximately 10% of the water samples analyzed during 1980, ~
but none of the levels _ recorded exceeded the 0.05 mg/l t VSWCB (1976) reference level.
i Based upon 1980 data it is felt that the high lead values recorded for the 1979 December (4th quarter) sampling ,
period were attributable to contamination of the sample l containers, and are not representative of lead in Lake Anna i
water. In 1980 lead occurred in only 5.5% of the December ;
samples and at levels shnilar to those obtained in previous studies, (Data Base). ;
1.3.2 Nutrients I
The overall mean for nitrate
. 1.3.2.1 Nitrate Nitrocen <
l nitrogen in Lake Anna water in 1980 was approximately 0.19 mg/l compared to 0.16 mg/l in 1979. Levels exceeding 0.20 !
i mg/l were recorded at stations lil, 121, 132, 231, 241 and 243 (Table All of these stations are in the sec- l tion of Lake1.3.2.1). Anna under the greatest influence by the power l Stations lil,121 and 132 are located in the WHTF, ;
{} station.
1-13
..,,---.-.,,w -
,.....m --.-.-.v_y.,,,,-----.,-**.,-w ,--
.,,-r+weww,,r--,e-si.- + + - -
l l
l l
4
'( )
while' stations. 231, 241 and 243 are in the Mid-or Lower Reservoir. Nitrate levels also increased at all other stations in 1980 compared to 1978 and 1979 levels (Table 1.3.2.1). The March and December samples exhibited the
. highest nitrate concentrations, 0.21 mg/l and 0.36 mg/l re-
.spectively. A similar. trend was noted in 1979, however, the December,1980 value (0.36 mg/1) is much higher. In general, the December,1980 nitrate values were greater for all stations than in 1979 and contributed to the higher overall average for nitrates noted above. June and September nitrate concentrations were lower (0.10 mg/l and 0.08 mg/1) as in noted past years. The highest single nitrate value, 0.66 mg/1, was recorded at 6 meters from station 121 in -
December. There was no significant difference in mean nitrate levels at the various depths sampled. None of the
< nitrate levels recorded exceeded the reference level of 0.9
- mg/l given by the VSWCB (1976) Water Quality Inventory.
l.3.2.2 Ammonia Nitrogen Ammonia in Lake Anna was low in 1980, following the trend of declining concentrations since 1975 (Table 1.3.2.1 ) . The overall mean, 0.3 mg/1, was lower than the 1979 value (0.4 mg/1) and well below the 0.29 mg/l
! , level given by the VSWCB Water Quality Inventory (1976).
Ammonia was detected in 62% of the samples analyzed. The largest mean values were recorded from September and December samples. Station 212 had the overall highest ammonia con-centration repeating the pattern noted in 1979. As observed in the past, hypolimnetic samples contained more ammonia than those from other depths. The single highest value (0.24 mg/1) was obtained from a 6 meter sample at station 212'in June. A concentration of 0.21 mg/l ammonia was ob-tain'ed from a 6 meter sample at station 223 in December.
1.3.2.3 Phosphate Total phosphorus in Lake Anna declined in 1980 compared tu 1979 and previous years (Table 1.3.2.1).
i It was detected in 87.5% of the samples compared to 98% in I
1979. Highest levels were detected in June and December (0.04 mg/1), while the March samples contained the lowest concentration of total phosphate, 0.02 mg/1. The Upper Reservoir and Contrary Creek total phosphate levels were higher than those of the Lower Reservoir and the WHTF as had been noted in 1979. The highest overall mean con-
! centration of total phosphate was obtained-from 4 meter samples, followed by the 6 meter samples. The maximum level
! recorded was 0.20 mg/l at 6 meters from station 231 in l December. Also in December a value of 0.18 mg/l total phos-
! phate was obtained from a 2 meter sample at station 212. No orthophosphate (soluble inorganic phosphate) was detected in the 160 samples analyzed.
{ 1-14 i
~ , _ _ , , - . , . _ _ _ . . . - - . _ , _ . ~,.-...m. - - - . . . - . . ,
( l.3.2.4 Sulfate The sulfate content of Lake Anna in 1980 (8.52 mg/l) was similar to that observed in 1979 (8.63 mg/1). Increases in concentration were noted at stations lil, 121, 132, 211, 212 and 241,. while sulf ate declined at stations 221, 223, 231, 241 and 243 (Table 1.3.2.1 ) . The Upper Reser-voir contained the lowest sulfate levels while the WHTF (8.5 mg/1) and Lower Reservoir were higher and similar in sulfate concentration (Table 1.3.2.1). As in previous years station 223, Contrary Creek, exhibited the highest levels of sulfate (14.0 mg/1) as a result of the iron pyrite and mine tailings in the Contrary Creek watershed. The highest overall con-centrations of sulfate in Lake Anna were noted in December, while the lowest occurred in September. The single high value (22.8 mg/1) was recorded from the March 2 meter sample at station 223, followed by the surface sample-(22.6 mg/1) from that station on the same date. The sulfate concentra-tions at st: tion 223 have historically been high during spring sampling due to iron pyrite runoff from the abandoned pyrite mine spoils along Contrary Creek. The trend of de-clining sulfate concentrations observed at station ?23 may be related to erosion control measures implemented at the mine spoils site through the State Water Control Board EPA () demonstration project. O 1-15
m
%Y TABLE 1.3.2.1 A COMPARISON OF MEAN ANION LEVELS (mg/l) IN LAKE ANNA WATER, 1975-1960 Station Year NH4 + 0-P0 4 T-PO 4 NO3 - SO4 =
111 1978 0.07 0.0 0.04 0.23 9.9 1979 0.04 0.0 0.03 0.17 8.1 1980 0.02 0.0 0.02 0.20 8.4 121 1975 0.488 0.02 0.11 0.238 9.0 9.0 1976 0.138 0.01 0.14 0.440 1977 0.086 0.01 0.30 0.256 11.9 1978 0.04 0.0 0.03 0.19 9.6 1979 0.03 0.0 0.02 0.17 8.4 1980 0.02 0.0 0.02 0.21 8.5 132 1975 0.411 0.02 0.10 0.226 9.0 1976 0.157 0.01 0.18 0.343 9.0 1977 0.100 0.02 0.37 0.205 10.4 () 1978 1979 0.05 0.02 0.0 0.0 0.03 0.03 0.14 0.17 11.1 8.4 1980 0.03 0.0 0.02 0.20 8.5 211 1975 0.515 0.06 0.26 0.135 10.0 1976 0.135 0.06 0.19 0.790 10.0 1977 0.118 0.02 0.29 0.254 16.7 1978 0.06 0.0 0.04 0.07 7.9 1979 0.03 0.0 0.07 0.11 5.7 1980 0.03 0.0 0.06 0.14 6.8 212 1975 0.709 0.09 0.25 0.155 19.0 1976 0.215 0.05 0.21 0.750 9.0 1977 0.117 0.03 0.38 0.211 18.8 1978 0.03 0.01 0.05 0.07 8.4 1979 0.07 0.0 0.06 0.16 6.0
. 1980 0.07 0.0 0.05 0.18 6.7 221 1975 0.585 0.02 0.16 0.147 10.0 1976 0.251 0.02 0.16 0.523 10.0 1977 0.160 0.02 0.40 0.221 10.8 1978 0.06 0.01 0.03 0.16 9.3 i 1979 0.05 0.0 0.05 0.16 8.0 1980 0.02 0.0 0.03 0.17 7.9 i ()
i 1-16 l
,----e -
% .--r y *r-=y-w-- e 9"*"***"t' e7 P* *9"7--'7-*t-w- *v--+=r-e-_
O TABLE 1. 3.2.1 (Continued) A COMPARIS0N OF MEAN ANION LEVELS l (mg/1) IN LAKE ANNA WATER, 1975-1980 Station Year NH4 + 0-P0 4 T-P0 4 NO3 - SO4 = 223 1976 0.113 0.03 0.14 0.245 19.7 1977 0.088 0.02 0.35 0.019 15.5 1978 - - - - - 1979 0.05 0.0 0.06 0.12 16.0 1980 0.04 0.0 0.04 0.16 14.0 231 1978 0.07 0.0 0.03 0.18 10.0 1979 0.04 0.0 0.05 0.17 8.5 1980 0.02 0.0 0.03 0.23 8.0 241 1975 0.507 0.02 0.11 0.139 9.0 1976 0.215 0.02 0.13 0.605 9.0 1977 0.115 0.02 0.48 0.245 8.7 1978 0.07 0.0 0.03 0.17 9.7 s 1979- 0.02 0.0 0.04 0.18 8.7 1980 0.04 0.0 0.04 0.20 8.0 243 1975 0.504 0.02 0.12 0.114 10.0 1976 0.108 0.02 0.18 0.594 10.0 1977 0.067 0.02 0.39 0.237 8.7 1978 0.08 0.0 0.05 0.17 9.6 1979 0.03 0.0 0.04 0.17 8.5 1980 0.04 0 -0 0.02 0.?0 8.3 () 1-17 l I
I l l ()
?
1.4 Summary i
- 1. Operation of the North Anna Power station did not adversely affect water quality-in Lake Anna in 1980.
- 2. -The Contrary Creek area continues to show the influence of acid mine drainage and tailings deposits. Heavy metals concentrations are greater and pH levels are low-er in that region of Lake Anna than in other areas.
- 3. Iron levels are greatly reduced in Lake Anna compared to 1979 data. Iron concentrations are greater in hypolim-netic water than at other depths.
- 4. Iron was detected in only 33% of the September water samples and was totally absent in September WHTF samples.
- 5. In 1980 only 35% of the iron values recorded in Lake Anna exceeded the Virginia State Water Control Board drinking water reference level of 0.3 mg/l compared to 58% in 1979.
- 6. Copper occurred in 15% of the samples analyzed nd was
)' (]) absent in September and December samples. Most of the copper detected occurred in June samples.
- 7. Zinc levels were similar to those noted in 1979. As in previous years, the Contrary Creek stations, especially station 222, exhibited the highest zinc concentrations and; zinc occurred most frequently in water samples from that area.
i 8. Lead continues to occur in trace amounts in Lake Anna. Quantities and distribution patterns of lead in 1980 were similar to those noted in 1979. t
- 9. High lead values reported in 1979 for the 4th quarter (December, 1979) sampling period are attributed to sample container contamination, based upon 1980 results.
- 10. Nitrate nitrogen increased in concentration in areas under the greatest influence of the North Anna Power ,
. Station. December values were greater at all stations ! I than in 1979. No adverse effects of increased nitrate levels .c Lake Anna were noted in 1980. 1-18 e emsi y w- , - y wa- + -g-pi.e---w3 wgy--gw--y e- '-wpii v pes e w my*wg*g*y -TW't e v y weg--- y se y'*wi-iewWMemywygw_
O
- 11. Ammonia nitrogen was low in 1980, following a trend of declining concentrations since 1975. The Upper Reservoir exhibited the highest ammonia levels in 1980 and as in previous years, the hypolimnetic water contained more ammonia than water at other depths.
- 12. Total phosphorus declined in Lake Anna in 1980. Highest levels were detected in June and December, while March samples contained the lowest concentrations of phosphate.
The Upper Reservoir and Contrary Creek phosphorus levels were higher than other areas of Lake Anna. No ortho-phosphate (soluble inorganic phosphate) was detected in 1980.
- 13. The sulfate concentration in Lake Anna water in 1980 was similar to that recorded in 1979. The Upper Reservoir contained the lowest sulfate levels while the WHTF and Lower Reservoir were higher. As in previous years, Contrary Creek exhibited the highest sulfate concentra-i l
tions especially in the spring due te acid mine drainage and runoff from iron pyrite deposits. O I i O 1-19
f o 1.5 Reference American Public Health Association, American Water Works Association, Water Pollution Control Federation. Standard methods for the examination of water and wastewater,14th Edi tion, Washington , D.C. ; 1976. Lee, G. F. Critical levels of phosphorus and nitrogen in Texas impoundments. Texas J. of Science. XXVIII (1-4); 347-350; 1977. National Academy of Sciences; National Academy of Engineering. EPA-Water quality criteria,1972. Washington, D.C. : R3-73-033; 1973. ' Reid, G.K. Ecology o" inland waters and estuaries. New York: D. Can Nostrand Company; 1961. Simmons, G.M., Jr., Annual report 1976. Preoperational envi-ronmental study of Lake Anna, Virginia. Richmond, VA: Virginia Electric and Power Company; 1977.
. Annual report 1977. Preoperational envi-ronmental study of Lake Anna, Virginia. Richmond, VA:
Virginia Electric and Power Company; 1978. O. Virginia Electric and Power January Company, Environmental 1,1978 - DecemberStudy 31, of Lake Anna, Virginia: 1978. A report of James R. Reed and Associates, Inc. to the Virginia Electric and Power Company. March 1979. Located at Virginia Electric and Power Company, Richmond, - Virginia. Virginia Electric and Power Company, Environmental Study of Lake Anna, Virginia: January 1, 1979 - December 31, 1979. A report of James R. Reed and Associates. Inc. to the Virginia Electric and Power Company. March 1980. Located at Virginia Electric and Power Company, Richmond, Virgina. Virginia State Water Control Board. Water quality inventory (305(b) Report), Virginia, 1976 Report to EPA Admin-istrator and Congress. Information Bulletin 526. 313-342: 1976. 1-20 - . . ... ~ '- - . ,
o productivity and Temperature Studies _ 2.0 Chlorophyll, primary The thermal profile nf the reservoir and Introduction 2.1 waste heat treatment facility is of primary interest when Most studies of thermal components in the aquatic system. effects on algae are focused on the measurements of primary productivity, i.e., Weiss, 1972). the rate of photosynthesis (Gurtz andprimary prod dent upon a number of variables such as changes in temp-erature, light and available nutrient In this study, supply primary (McMahondeter-productivity and Docherty, 197C).minations and temperature profiles were utilized in correlv: ing observed trends. Chlorophyll studies are useful in determining algal () s+anding crop and in the trophic system of lake classifica-Thus far, Lake Anna has been classed as a mesotrophic l tion. lake based uponChlorophyll its chlorophyll and phytoplankton composition analysis was undertaken and the f (V EP CO , 1976 ) . results evaluated in relation to phytoplankton, primary pro-ductivity and physical factors. , 2.2 Methods and Materials Chlorophyll _ .At the five primary productivity stations 2.2.1 (121,132, 221, 241, 243), (Figure 2.2.1.1) water samples were drawn at one-meter intervals from zero to five meter depths. Only surface samples were drawn at the remaining five 1).produc-tivity stations (111, 211, 212, 223, 231), (Figure 2.2.1. All chlorophyll stations are located in open water areas with l the exception of 211 and 212, which are located near the Route 719 bridges in the North Anna and Pamunkey Rivers, re-spectively. Sampling frequenci was once per month with the exception of June, July and tagast when samples were drawnCol twice per month. hours using a plastic water sampler. O 2-1
O O O 2 1 0 2 212 Kilometers L i f N I 9 Rt.719 1 Rt '208 d k 21 l ; I 211 * . 241 223 , i 231 y Power /
- Station ,
j l 11
, 243 e
121 132 Piqure 2.2.1.1 General location of chlorophyll sampling station in Lake Anna, 1980. Primary , productivity stations are underlined. e
O Magnesium carbonate (MgC0 2 ) was added to the samples following the procedure outlined in Standard Methods for the Cooled Examination of Water and Wastewater (APHA,Reed 1976). and Associates, samples were transported to the James R. Inc. biological laboratory in Newport News, Virginia for filtration. Samples were filtered onto glass fiber filters which were then placed into centrifuge tubes containing 10 ml. of 90% acetone (V/V). The tubes were kept at 0*C over-night furing the extraction process, then centrifuged at The chlorophyll extract was 500 x G for twenty minutes. decanted into graduated centrifuge tubes and absorption read-ing, were taken on a Turner Model 350 Specteophatometer. 3 In deiermining the amount of chlorophyll (mg/m ), the , following calculations were used (APHA, 1976): Chl . a concentration in sample = 11.640663 -2.160 645 -0.100 630 Chl. b concentration in sample = 20.97D645 -3.94D663-3.66D630 Chl. c concentration in sample = 54.22D630-14.810645-5.550663 Chl n (mg/1) x Ex. tract Vol. (ml.) Chlorophyll n (mg/m3 ) = ({} Filtered Volume (liters) where D = Optical Density (Absorbance) n = a, b or c 2.2.2 Primary Productivity At primary productivity stations (121, 13'2, 221, 241, 243) (Figure 2.2.2.1), samples for primary productivity, total alkalinity, pH and background readings were drawn with a non-metallic water sampler at one-meter Sampling frequency intervals was from depths of zero to five meters. twice per month in June, July and August and once per month at all other times in 1980. All primary productivity stations are located in open water areas with an average depth of 14 meters. Total alkalinity was determined by potentiometric titra-tion to pH = 4.5 (APHA,1976). Both alkalinity and pH measure-ments were made with a Corning Model 5 pH Meter. Primary productivity analysis was performed following the I procedure outlined in Standard Methods for the Samples Examination from each depth of Water and Wastewater (APHA, 1976)." dark" bottles (300-ml . 800 bottles were placed into light and painted black then wrapped with duct tape) 1 containing a broken The samples ampoule of 5 uCi of 14C (labelled as NaH 4C03). were then placed at the depths from which they were drawn via an anchored and buoyed hanger. Hangers were set between 0830 incubation O and 1130 hours and left for a four hour in situ-- l period. 2-3
" i o ,
f g a Z = g N 8
- A8
. ~
~
! si '
!} 3 t.
$8 C
82 O ;! as t2 a 44 e4 o a 88 D'u 83 S* E' 0d E s' c 83
~.
N o
-u O
2-4 ,
O Each background, light and dark subsample was filtered onto HC1. a 0.45 um pore size membraue filter and rinsed with 5 tion vials containing 10 ml. of scintillation cocktail The I (scintillation grade toluene and Liquifluor (NEN). samples were then counted by Analytics Laboratory in Richmond, Virginia. ductivity (Vollenweider,1969, Lind,1974, and APHA,1976) L cpm -D epm +BKG cpm
. Net x 1.06 xAlk. xC Photosynthetic Rate = E 3 7 (mgC/m /hr 1.11 x 10 dpm
= counts per minute as recorded where: L cpm, Depm, BKG cpm by the scintillation counter E = scintillation counter efficiency 4 C
i.08 = compensat4on for slower upteke of O 12 C molecule in relation to 14C added 1.11 x 10 7 = disintegration per minute of Alk. = recorded as mg/ liter Bottled Vol. C = (0.25) (- ) (1000)( Alk. correction factor) Filtered Vol. where: 0.25 = factor to reduce measurements to an hourly rate 1000 = factor to convert measurements to m3 Alk. correction factor = dependent upon l temperature and pH reading To assess other factors influencing primary production, solar radiation, light penetration aid dissolved oxygen were InstrumentCompanypyrhel{ometer also measured. A Belfort
'Model S-3850A) measured solar radiation (gm-cal /cm / day) f or fMontedoro-WhitneyCorporation),andtransparencywasmeasured O
2-5 Imm
1 l with a secchi disc. Dissolved oxygen readings were taken via a Yellow Springs Instrument Company, Inc. Model 54A Dissolved Oxygen Meter. Table 2.2.2.1 lists methods and equipment utilized in the course of productivity analysis. General climatic conditions such as wind velocity, precip-itation and cloudiness were also noted to aid in data interpretation. These conditions are stated in the physical-chemical portion of the Data Base. The primary productivity stations 2.2.3 Statistical Analyses (121, 132, 221, 241, 243) _(Fi3ure 2.2.2.1) were analyzed using an ANOVA on dates by station. These results were then placed
- into statistically significant groups using a Tukey's w-procedure. Stations that were not significantily different A space sepa-were grouped together by a horizontal line.
rating two lines indicates that the two groups were statistically different. Chlorophyll for the complete lake couldMeans only for be analyzeda_ chlorophyll using surface water data (see 2.2.1). were determined by quarters and analyzed by an ANOVA by quarter by station. The results were ordered and analyzed as above us-ing Tukey's w-procedure. 221, 223, 231, O During the month of February, 1980 stations 241 and 243 could not be sampled for primary productivity or chlorophyll because of ice cover. 2.3 Results and Discussion 2.3.1 Chlorophyll Chlorophyll a, b, c and total chlorophyll (the sum of chlorophyll a, b and c)_d'eterminations for all samples are given in the Data Base. Results of an ANOVA of chlorophyll data by quarter by station The shows first,a second significant and difference between quarters in 1980. third quarters are within one group and the fourth quarter is ra:.ked lowest in another group (Table 2.3.1.1). A review of the mean chlorophyll a values for each station throughout t.'te year shows station 221 with the highest mean and stations 212 and 221 following with 8.4 value (12.4 mg/m3)3 mg/m3 and 7.1 mg/m respectively. This correlates well with 211, 212 and 221 had the highest phytoplankton data as stationsnumbers of phytoplankton /ml within the lake (Tab 2.3.2 primary Productivity The five primary productivity sta-tions (121,132, 221, 241, 243) were compared using an ANOVA O 2-6
O TABLE 2.2.2.1 ANALYTICAL PROCEDURE FOR DETERMINATION OF WATER QUALITY PARAMETERS AT PRODUCTIVITY STATIONS I Method Parameter Belfort Instrument Company Solar Radiation Pyrhelioneter Model LMD-8A Whitney Photometer - Light Penetration (Montedoro-Whitney Corporation) Transparency Secchi disc (20 cm diameter) APHA Standard Methods, 1976 Alkalinity Corning Model 5 pH Meter pH Yellow Springs Instrument Model Dissolved Oxygen 54 0xygen Meter {]) Yellow Springs Instrument Model Temperature 54 0xygen Meter Chlorophyll a, b and c Spectrophotometric Determination b and c APHA of chlorophyll Standard a, T976 Methods, Carbon 14 Method, APHA, Standard Primary Productivity Methods, 1976 l llI 2-7
o _ S r E e U t L r A a 2 V u . Q 1 a h L t L 4 Y H P r O e R t . O r L a H u 7 C Q . 3 _ Y d L r _ R 3 E T0 R8 r A9 e U1 t Q r a O NA AN EN MA Q u t 5 7 e e-s .- FE e 1 w OK - e A w NL r O e m m SN t w IO r w R a e w A) u 7 m P3 Q . w _ Mm 7 v w v O/ d - w Cg n w
=
=
m 2 A( _ 1 a_ - 1 l
. l
_. 3 y
. h
_ 2 p o _ E r L 0 o B 8 l A 9 h T _ 1 C O 7m
O o o TABLE 2.3.1.2 .A RANKING 0F MEAN CHLOROPHYLL a, VALUES (mg/m3) 0F SAMPLING STATIONS ON LAKE ANNA, 1980. 211 212 221 231 111 223 241 121 132 243 Station Chlorophyll a 12.4 8.4 7.1 3.8 3.3 3.1 3.1 3.0 3.0 2.9 7o 6 e
O TABLE 2.3.2.1 TUKEY'S w-procedure TEST OF PRIMARY PRODUCTIVITY DATA, DATE BY STATION, LAKE ANNA, 1980 i Month Stations JAN 132 221 241 121 243 FEB No sampling due to ice cover MAR 121 221 241 243 132 APR 121 241 243 221 132 MAY 243 121 221 132 241 JUN1 221 241 243 121 132 JUN2 121 132 221 241 243 JUll 121 132 221 243 241 (]} JUL2 221 241 121 243 132
, AUG1 121 221 132 243 241 AUG2 221 121 132 243 241 f SEP 221 132 243 121 241 OCT 221 243 121 241 132 NOV 132 121 221 241 243 DEC 221 241 243 121 132 i
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I O 3 TABLE 2.3.2.2 MEAN PRIMARY PRODUCTIVITY VALUES (mgC/m /Hr), LAKE ANNA, 1980 Stations Month 121 132 221 241 243 Monthly Mean JAN 1.8 1.8 1.7 1.6 1.1 1.5 FEB No simpling due to ice cover 6.5 5.9 MAR 9.1 5.1 7.6 6.8 . APR 4.6 1.6 2.3 4.3 3.0 3.2 MAY 6.7 4.3 6.5 3.8 7.0 5.7 JUN1 6.9 6.2 14.1 7.7 7.2 8.4 , JUN2 11.7 10.6 9.5 8.7 5.3 9.2 JUL1 9.4 8.6 6.6 2.4 4.0 6.2 JUL2 6.6 4.3 18.1 11.8 4.8 9.1 , AUG1 12.2 11.4 12.0 6.6 7.1 9.9 AUG2 4.5 4.0 5.9 1.6 3.2 3.8 SEP 2.3 9.0 20.6 ,1. 3, 3.6 7.4 OCT ,14.0 8.5 15.1 10.0 14.1 12.3 NOV 5.2 7.1 5.0 3.7 2.5 4.7 0.8 0.7 DEC 0.6 0.3 0.8 0.8 l t h 2-11 ; i
i l') \
%.J and Tukey's w-procedure. The ANOVA of date by station showed that in 12 of 14 samplings there was no significant oifference in productivity between the five stations (Table 2.3.2.1).
Two months, JUL2 and SEP, did show a difference between stations. During the JUL2 sampling stations 221 and 241 were ordered in a higher grquping. Stations 221 and 241 had values while the other stations of18.1and11.8mgC/m3/hrresSectivelhadvalueslessthan7.0mgC/a/hr(Table During 2.3.2.2). ignificantly higher the thanSEP sampling other stations stations 221 and with 20.6 and9.0 132mgC/m3 were g/hr respectively while the other stations had values of less than 4.0 mgC/m3/hr (Table 2.3.2.2). Reviewing mean productivity values for the overall year3 shows October with the highest mean value of 12.3 mgC/m /hr. The summer months in general were higher than other months, except October, with values averaging around 8.4-9.1 (Table 2.3.2.2). Photosynthetic rates are influenced by many variables such as temperature, light intensity, nutrient availability, phytoplankton density and alkalinity. Overoptimum light con-ditions can provoke a reduction in photosynthetic rates (~}
\- (Wetzel, 1975; Prescott, 1968; Tilzer and Horne, 1979). The de-crease in primary production is associated with photo-oxidative destruction of enzymes and does not involve destruction of the chlorophyll (Wetzel, 1975).
Generally moderate increased in temperature stimulates photosynthesis, however, the effects of light and temperatures on phytosynthesis and growth of algae are inseparable.because of the interrelationships in metabolism and light saturation. In this investigations of the effects of thermal effluents
, upon phytoplankton populations, Lind found that a definite light-temperature relationship existed (Lind,1974). A common change in photosynthetic rates of phytoplankton is an increase in the rate of which light saturation occurs at higher temperatures (Wetzel, 1975).
Estimation of primary productivity rates is of importance in analyzing the state of an aquatic system as algal photo-synthesis is the major process in which energy is supplied for higher trophic levels such as zooplankton and fish (Wetzel, 1975). There is a limited number of investigations based on long term, constant exposure of an aquatic ecosystem to thermal effluent and cycling associated with nuclear reactor O 2-12
sites such as Lake Anna. The comparisons of data within and between report years affords observations useful in projecting trends as construction of the reactor site progresses toward completion. 2.3.3 Temperature Temperature data for all stations and sampling dates are listed in the Physical and Chemical tables (Data Base). The water temperature peaked at 34 C on August 15, 1980 at station 111. It can be assumed that the thermal effluent has an effect on station 111, but surface tempera-tures throughout the lake ranged from 28.0*C to 34.0*C on that same'date. A review of the temperature data for the year shows station 111 higher than other stations only in the cooler , months, particularly February, April and October. This would be expected as it receives a direct input of thermal effluent which would dissipate quickly in the cooler months and not necessarily affect other stations. A comparison of the stations in the WHTF to the sta-tions in the main body of the lake did not show any great differences in temperature except at station 111 (Data Base). This was also the case in 1978 and 1979 (VEPC0 1978, VEPC0 O 1979). 2.4 Summary 2.4.1 . Chlorophyll
- 1. The two upper reservoir stations (211 and 212) showed the highest levels of chlorophyll in 1980, particularly
. station 211. This was also the case in 1979.
- 2. Mean chlorophyll values for the four quarters of 1980 showed the 1st. 2nd and 3rd quarters to be significantly higher than the 4th quarter.
2.4.2 Primary Productivity
- 1. The JUL2 and SEP samplings were the only dates to show a significant difference between stations.
- 2. Sampling in the month of October showed the highest mean value for mgC/m3/hr for the year.
() 2-13
2.4.3 Temperature
- 1. Station 111 showed higher temperatures than other sta-tions during the cooler months, which is a result of ,
being located.directly downstream from the reactors' ; discharge canal.
- 2. Comparisons of the stations showed relatively little differences in mean temperature values. This was also the case in 1978 and 1979.
O t e i l O l 2-14 \
(
- 2. 5 - Reference A. P.-H. A., et. al. Standard Methods for the Examination of Water and Wastewater.14th Edition; Washington, D.C.;
1976. Gurt:, Martin E. ; Weiss , Charles M. Field Investigations of the response of phytoplankton to thermal stress; E.S.E. Publication No. 321; December 1972 Illinois Natural History Survey; Lake Sangchris Project. Annaul Report for Fiscal Year 1974. Urbana, Illinois; 1974. Located: Illinois Natural History Survey, Urbana, Illinois. . Lind, Owen T. Handbook of Common Methods in Limnology; The C.V. Mosby Company; Saint Louis, Mo.; 1974.
, Venables, B.J.,'iysong, Mark,; Lukins, D.L.
The relationship of electric power station thermal cir-culation to biological productivity of reservoirs; Baylor University; Project Number B-091-TEX; January, ([) 1974. McMahon, J.W.; Docherty, A.E. Effects of heat enrichment on species succession and primary production in freshwater plankton. Environmental Effects of Cooling Systems at Nuclear. Power Plants; Symposium IAEC; 1975. Prescott, G.W. The Algae: a Review. Houghton Mifflin Company, Boston, Mass; 1968. Tilzer, M. M.; Horne, A. J. Diel patterns of phytoplankton productivity ar.d extracellular release in ultra-oligo-tropic Lake Tahoe. Int. Revue ges. Hydrobiol. 64(2):157-176; 1979. Virginia Electric and Power Company, Environmental Study of Lake Anna, Virginia: January 1, 1976 - December 31, 1976. Virginia Electric and Power Company, Richmond, Virginia. Virginia Electric and Power Company, Environmental Study of Lake Anna, Virginia: January 1, 1978 - December 31, 1978. A report of~ James R. Reed and Associates, Inc. to the Virginia Electric and Power Company, March 1979. Located at Virginia Electric and Power Company, Richmond, Virginia. O 2-15 l l . .
l l l Virginia Electric and Power Company, Environmental Study of [ Lake Anna, Virginia: January 1, 1979 - December 31, 1979. A report of James R. Reed and Associates, Inc. l to the Virginia Electric and Power Company. March 1980. Located at Virginia Electric and Power Company, Richmond, Virginia. Vollenweider, Richard A. A Manual on Methods for Measuring Primary Production in Aquatic Environments, IBP Hand-book No. 12; F.A. Davis Company; Philadelphia, Pa.,
.1969.
Wetzel, Robert G. Limnology. W. B. Saunders Company; 1975. i l 2-16
(~) L.) 3.0 Phytoplankton Studies 3.1 Introduction Phytoplankton . microscopic free-floating algae, are an important component of the aquatic ecosystem, performing the vital ecological function of-photosynthesis (the storage of solar energy through the synthesis of organic matter from carbon dioxide and water). They are positioned at the base of the aquatic food web and as such are a necessary focal point for studies of thermal effects upon aquatic commu-nities (Gurtz and Weiss,1972). 3.2 Methods and Materials 3.2.1 Sampling Procedure Individual 60-ml. phytoplankton samples were drawn at one-meter intervals from depths of zero () to five meters at the primary productivity stations (121,132, 221, 241, 243), (Figure 3.2.1). At each of the remaining pro-ductivity stations (111, 211, 212, 223, 231), a-composite 250-ml. sample from 0,2,4 and 6-meter depths was collected. All
.phytoplankton sampling stations were located in open water areas with the exception of stations 211 and 212, which were located near the Rt. 719 bridges in the North Anna and Pumunkey river area of the' impoundment, respectively. Data were col-lected twice per month in June, July and August and once per month at all other times of the year. In most cases, samole collection took place between 1800 and 1200 hours.
A non-metallic water sampler was used for collection purposes. The samples were preserved with 4% Lugol's and 30% formalin. Each sample was introducted into a 50-ml. settling column positioned on plate chambers (Wild Heerbrugg Instruments, Inc.) and allowed to settle for a minimum of eight hours. A Wild Heerbrugg Model M40 Inverted Microscope with phase con-trast optics and 10X, 40X and 100X objectives was used in identifying and enumerating phytoplankton. Standard keying texts were utilized to assist in identification (Whitford and Schumacher 1973, Cocke 1967, Prescott 1979, and Smith 1950). With few exceptions taxonomic classifications were made to the genus level. After analysis, the sample was then transferred to a 10-ml. vial for the reference collection. Data were reported as number of organisms per milliliter of sample. O 3-1 l
O o o 2 1 0 2 212 O Kilometers Rt.719 i I R .208 H 221 211 , b.
^
u 223 , 231
.?
N Power, . Station
'lll e 243 121 132 Figure 3.2.1. General location of phytoplankton sampling stations in Lake Anna, 1980. Primary productivity stations are underlined.
e
DV 3.2.2 Statistical Analyses The technical specifications of int monTtoring program required two types of sampling; con-
'nuous and composite. Data were collected from 0,1,2,3,4 and s depths for continuous sampling while composite sampling
- . lected data from 0,2,4 and 6 m depths. The continuous
- ions were 121, 132, 221, 241 and 243, while the composite
. _.lons were-111, 211, 212, 223 and 231.
Due to ice cover in February only stations 111, 121, 132 211 and 212 were sampled. For the remainder of the year data were collected at all stations. An ANOVA of the phytoplankton density by date and by r station was performed on the continuous data. These results . were then placed into statistically significant groups using - the Tukey's w-procedure. Stations that were not significantly different were grouped together by a horizontal line. A space separating two lines indicate that the two groups were statis-i tically different. It is possible for two groups to overlap l and a station may be included in two or more groups. l l 3.3 Results and Discussion The ANOVA of phytoplankton data for date oy station is summarized in Table 3.3.1. A Tukey's
.(]) test statistically grouped and ordered the stations by de-creasing mean density.
Station 221 had the highest mean density of the continuous stations (primary productivity stations) for 10 of the 15. 1 samplings. It was in the highest grouping for 12 of the 15 samplings (Table 3.3.1). This station aeaked during the i JUL2 ampling with a average of 5317.6 2eganisms/ml. Although not statistically analyzed, stations 211 and 212 had compar-able numbers with 4039/ml and 4763/ml respectively (Data Base). In 1979 station 221 had the highest mean density of continuous stations as it was in the highest group 13 of 15 samplings (V PCO, 1979). However, in 1978 it was in the highest group-ing only 6 of 15 samplings (VEPC0, 1978). Station 121 was ranked lowest of the continuous stations i for 8 of.15 samplings. This was different from 1979 where station 121 was ranked lowest only 1 of 15 samplings (VEPCO, 1979). Although not statistically analyzed station 223 had lower densitities (Data Base). This may be attributed to acid mine drainage upstream of station 223. The blue-greens are ; more likely to tolerate fluctuations in pH that can occur at :' station 223 due to acid-mine drainage in Contrary Creek and may actually dominate at this station due to the lower pH, since l I ($) f 3-3 i I
O
-' uJ
-TABLE 3.3.1 TUKEY'S w-procedure TEST OF CONTINU0US PHYTOPLANKTON DATE, DATE BY STATION, LAKE ANNA, 1980 JAN 221 241 1 21 243 132 FEB 132 121 MAR 221 121 243 132 241 APR 221 132 121 243 241 MAY 241 221 132 243 121 JUN1 221 241 132 121 243 JUN2 243 221 241 132 121 1
JUL1 221 241 243 132 121 (]) JUL2 221 132 241 243 121 AUG1 221 243 132 121 241 AUG2 221 132 243 241 121 l t SEP 132 243 221 241 121 OCT 221 241 243 132 121 ; l NOV 221 132 121 354 241 DEC 121 132 241 243 221 l l l i i i O 3-4
(3 x> it has been shown that blue-greens out-compete greens at low-er pH values (Broch 1973, Shapiro,1973). An investigation of the raw data base revealed that the abundance of-phytoplankton was largely dominated (numerically) by Cyanophyta (blue-green algae) and Chlorophyta (green alagae). In terms of biomass'or unit volume, which may be biologically more important, Chlorophyta was more dominant. Representative volumes for genera found in Lake Anna are presented in Table 3.3.2. The cooler months (January through April) c?peared to be dominated by Bacillariophyta (diatoms) with Asterionella, Tabellaria and Cyclotella as typical genera. Cold water temper-atures and increasing light are believed to be the major factors.
- influencing the increase in diatom numbers in the late winter and their dominance in the spring (Marcus, 1972 and Watzel, 1975).
As temperatures warmed up in the summer months t Chlorophyta began to increase in numbers. Genera such as ' Crucigenia, Microspora, Dictosphaerium and Closterium were evi-dent in the summer samplings. In the autumn Cyanophyta popula-(s tions increased in numbers, particularly Microcystis, Chroccoccus (-) and Aphanocapsa. The predominance of Cyanophyta in the late summer and early fall months is generally expected in the annual cyclic fluctuatio'ns of this group (KreN 1973, Wetzel,1975, Sha pi r41973 ; Illinois Natural History Survey,1974). Since blue-greens are able to withstand higher temperatures than other algae they are generally the only algal organisms tolerant of temperatures greater than 35*C (Wetzel, 1975). This progression of Bacillariophy,ta to Chlorophyta to Cyanophyta populations within a lake is typical of temperate lakes. In the spring with decreased completion, cool temperatures and high nutrient availability, Bacillariophyta can dominate the phytoplankton populations. After a spring maximum of diatoms, rilica concentrations become limiting and warmer temp-l eratures occur, which favor Chlorophyta and Cyanophyta. This is ! particuraly evident at temperatures above 15*C (Wetzel, 1975). The phytoplankton community is an appropriate. target for , dynamic investigation in that algae are the primary sources of l ' energy for other trophic levels and that they have the capacity ! at high bloom densities of raising the pH values of water through the removal of carbon dioxide during growth resulting , in die-offs of zooplankton (Pulis, 1971). In the most severe : situations, changes in the composition of the algal community j I'l !'
\./
f 3-5
m
' G9 can disturb the base of the normal aquatic food web, perhaps eliminating many consumer species and resulting in the de-struction of the existing food web and the construction of new webs of less value. In cases where nuisance species dominate due to a lack of consumer species capable of uti-lizing them, the formation of obnoxious blooms is possible.
The production of extracellular substances and products of decaying algae on a large scale may be toxic to other aquatic life (Marcus 1972). Investigating the postoperational effects on the phyto-plankton community of a power plant during its first year of operation, Kreh (1973) observed no influence of plant opera-tion on algae numbers, biomass, species composition and . diversity. For Lake Anna, there also appears to be no observ-able impact of the operation of Unit 1 or Ur,it 2 upon the algal community. 3.4 Summary
- 1. Station 221 had the highest mean density of the primary productivity stations during 1980.
- 2. Bacillariophyta (diatoms) appeared to dominate the phyto-plankton community in the spring. Chlorophyta (green algae) was the next dominant group in the late spring /
early summer followed by Cyanophyta (blue green algae) in the late summer / autumn.
- 3. This pattern of diatoms-greens-bluegreens is a typical successional series for temperate lakes.
l I a 3-6
s () TABLE 3.3.2 PHYTOPLANKTON TAXA AND CORRESPONDING UNIT VOLUMES FOUND IN LAKE ANNA, 1980 Taxa Unit Volumes (um3 ) Division Cyanophyta Order Chroococcales Family Chroococcaceae Genus Agmenellum 3.0 , A>hanocapsa 4.0 Aphanothece 13.0 , _Chroococcus 905.0 [ Dactylococcopsis 77.0 ; Gloeocapsa 19.0 Gloeothece 15.0 (]) Microcystis 1.2 Entophysalis 40.0 l Order Oscillatoriales (Hormogonales) ; Family Oscillatoriaceae l Genus Arthrospira 41.0 l Lyngbya 4.7 ; Oscillatoria 18.0 l i 39.3 Spirulina l Trichodesmium 300.0 ; I Order Nostocales l i Family Nostocaceae 270.0 l Genus Anabena 270.0 j Division Chlorophyta 350.0 . Order Volvocales l Family Chlamydomonadaceae ; Genus Chlamydomonas 384.0 C) l i 3-7 ! l < i i
G.
\J TABLE 3.3.2 (Continued) PHYTOPLANKTON TAXA AND CORRESPONDING UNIT VOLUMES FOUND IN LAKE ANNA, 1980 Taxa Unit Volumes (pm3)
Family Volvocaceae
~
Genus Eudorina L .0 , Order Tetrasporales Family Coccomyxaceae Genus Elakatothrix 16.0 Order Microsporales Family Microsporaceae Genus Microspora 430.0 l Order Chlorococcales () Family Mic'ractiniaceae ! Genus Golenkinia 180.0 i Family Coelastraceae Genus Coelastrum 115.0 Family Hydrodictyaceae Genus Pediastrum 79.0 Family 00cystaceae , i Genus Ankistrodesmus 105.0 Chodatella 167.b Closteriopsis 1,232.0 Dictyosphaerium 14.0 Franceia 190.0 Kirchneriella 43.0 Nephrocytium 65.0 Oophila 1,300.0 i Pachycladon 400.0 i Quadrigula 115.0 ; () : 3-8
. - - . - - - - - - - - I
O
.a TABLE 3.-3.2 (Continued) PHYTOPLANKTON TAXA AND CORRESPONDING UNIT VOLUMES FOUND IN LAKE ANNA, 1980 Taxa Unit Volumes (um3)
Schroederia 140.0 , Selenastrum . 126.0 Tetraedron 179.0 Family Scenedesmaceae Genus Actinastrum 4 400.0 Crucigenia 32.0 Scenedesmus 135.0 Tetradesmus 150.0 Tetrastrum 134.0 ( Order Zygnematales 700.0 Family Desmidiaceae Genus Arthrodesmus 188.0 Closterium 2,048.0 Cosmarium 2,027.0 Cosmocladium 400.0 Euastrum 1,827.0 Groenbladia . 475.0 Hyalotheca 1,454.0 l l Micrasterias 26,546.0 l Pleurotaenium 552,905.0 l Soondylosium 624.0 f Staurastrum 3,190.0 Division Chrysophyta ! Order Ochromonadales l ! Family 0chramonadaceae Genus Ochromonas 85.0 ! l h 3-9 ; l [
\
rs
'\
TABLE 3.3.2 (Continued) PHYTOPLANKTON TAXA AND . CORFESPONDING UNIT VOLUMES FOUND IN LAKE A N N.'4 , 1980 Taxa Unit Volumes (um3) Family Dinobryonaceae Genus Dinobryon 93.0 Family Synuraceae l Genus Synura 87.0
- Order Mischococcales Family Sciadaceae l
Genus Ophiocytium, 289.0 - - i- Division Bacillariophyta Order Eupodiscales () Family Coscinodiscaceae Genus Cyclotella 292.0 Melosira 216.0 Order Fragilariales Family Fragilariaceae l Genus Asterionella 600.0 Diatoma . 2,937.0 Fragilaria 150.0 Synedra 250.0 Tabellaria 775.0 i Order Achnanthales Family Cymbellaceae Genus Amphora 200.0 l Cymbella 300.0 Family Gomphonemaceae Genus Gomohonema 176.0 0 3-10
-O V
TABLE-3.3.2 (Continued) PHYTC'OLANKTON TAXA AND CORRESPONDING UNIT VOLUMES FOUND IN LAKE l ANNA, 1980 Taxa Unit Volumes (mm3) Family Naviculaceae Genus Navicula 168.0 Pinnularia 1,080.0 Order Surirellales Family Surirellaceae ^ Genus Sulj rell a 3,800.0 Order Nitzschiaies Family- Nitzschiaceae 240.0 Genus Nitzschia () Division Euglenophyta Order Euglenales Family Euglenaceae Genus Lepocinclis 1,800.0 Phacus 14,807.0 Trachelomonas 10,016.0 Division- Pyrrophyta
. Order Gymnodiniales Family Gymnodiniaceae Genus Gymnodinium 194,052.0 Order Peridiniales Family Certiaceae Genus Ceratium 10,513.0 Family Peridiniaceae .
1 Genus Peridinium 3,889.0 3-11
TABLE'3.3.2 (Continued)* PhY'TOPLNAKTON TAXA AND CORRESPONDING UNIT VOLUMES FOUND IN LAKE ANNA, 1980 , Taxa Unit Volumes (um3 ) Division Crytophyta
. Order Cryptophyceae Family 'Cryptochrysidaceae Genus Cryptomonas 550.0 O
e 0 3-12
' ^
O 3.5 Reference Brock, T.D. Lower' pH limit for the existence of blue-green algae: Evolutionary and ecological implications. Science 179: 480-483. 1973. Cocke, Elton C. The Myxophyceae of North Carolina. Wake Forest University; .Winston-Salem, North Carolina; 1967. Gurtz, Martin E., Weiss, Charles M. Field investigations of the response of phytoplankton to thermal stress; E.S.E. Publication No. 321; December 1972. Illinois Natural Survey. Lake Sangchris Project. Annual Report for Fiscal Year 1974. Urbana, Illinois; 1974. Located: Illinois Natural History Survey, Urbana, Illinois. Kreh, Thomas V. An Ecological Evaluation of a Thermal Dis-
' charge. Part VII: Postoperational effects of a power plant on phytoplankton and community metabolism ia western Lake Erie. Technical Report Number 321; Institute of Water Research; Michigan State University; July, 1973.
(]} 4 Marcus, Michael D. An Ecological Evaluation of a Thermal Discharge. Part II: The distribution of phytoplankton and primary productivity near the western shore of Lake Erie. Technical Report No. 14; Thermal Discharge Series; Institute of Water Research; Micnigan State University;
- May, 1972.
Prescott, G.W. How to Know the Freshwater Algae. Wm. C. Brown Company Publishers; Dubuque, Iowa; 1970. Pulis, L.C. The influence of stream condenser effluent on freshwater phytoplankton. Cornell University; Ithaca, N.Y.; January, 1971. Shapiro, J. Blue-green algae: Why they become dominant. Science 179: 382-384. 1973. , Smith, Gilbert M. The Fresh-water Algae of the United States. I Second edition; McGraw-Hill Book Company, Inc.; N.Y.; 1950. () l 3-13
.(-).
'v'
' Virginia Electric and Power Company. North Anna Power Station Preoperational Environmental Report. A report'of VPI & SU and Virginia Commonwealth Univ. for Virginia Electric and Power Company; 1976. Located at Virginia Electric and Power Company, Richmond, Virginia.
Virginia - Electric and Power Company. Environmental Study of Lake Anna, Virginia: January 1, 1978 - December 31, 1978. A report of James R. Reed and Associates, Inc. to the Virginia Electric and Power Company. March 1979. Located at Virginia Electric and Powftr Company, Richmond, Virginia. Virginia Electric and Power Company. Environmental Study of Lake Anna, Virginia: January 1, 1979 - December 31, 1979. - A report of James R. Reed and Associates, Inc. to the Virginia Electric and Power Company. March 1980. Located at Virginia Electric and Power Company, Richmond, Virginia. Wetzel, Robert G. Limnology. W. B. Saunders Company; 1975. Whitford, L. A.; Schumacher, G. J. A Manual of Fresh-water () Algae. Sparks Press; Raleigh, N.C.; 1973. I I I O 3-14 l {
I i l 1 V 4.0 7.ooplankton Studies 4.1 Introduction This study was performed to determine the effects of the power plant on the zooplankton population of Lake Anna. It was an important study in that zooplankton are a major aquatic food source and they are among the organisms ' identified as having "the grettest potential for being affect-ed by station operation" (Nuclear Regulatory Commission,1977). 4.2 Materials and Methods 4.2.1 Sampling Procedure Zooplankton samples were collected in accordance to Environmental Technical Specifications for Virginia Electric and Power Company (Nuclear Regulatory Commission, 1977). The samples were collected at the surface r-) (_,- and at one meter intervals to a depth of five meters at sta-tions 121, 132, 221, 241 and 243. Samples were taken at the surface and at even meter depths to a depth of six meters at stations 111, 211, 212, 223 and 231 (Figure 4.2.1.1). The samples were collected using a 5 liter Niskin sampler. The 5 liter samples were filtered through funnels with 37 pm nylon mesh glued to a pair of " windows" cut out of each funnel. The funnels were plugged and held in place on ring stands with clamps. After filtering, the concentrated samples were then drained into 4 ounce glass sample jars. The funnels were rins-ed into sample jars using distilled water. Two milliliters of club soda were added immediately and the samples were preserved as soon as possible with 2 ml of 30% formalin. The addition of club soda acts to relax the zooplankton so they do not contract when the formalin is introduced. After allowing the samples to settle 2-3 days they were drawn down to approximately 30 ml and l 2 ml of 30% formalin were added. Two complete Sedgwick-Rafter cell counts were made under 4X magnification for each sample collected. The 1 ml aliquot l sub-sample for the counts was obtained using a Hensen-Stemple , pipet. After two 1 ml aliquots were removed, the remaining i sample volume was determined with a graduated cylinder and used to estimate zooplankton dens 1ty per liter. This volume O 4-1 "y c - --
O O O 2 1 0 2 E2 En C S f Pamunkey Creek I 212 I 5 221 211 * ', North Anna River 4 223 s 231 Power
- 6 Station 23 111 132 Figure 4.2.1.1 Zooplankton sampling stations on Lake Anna, 1980.
~
\
l l N_] was returned to the sample jar and allowed to resettle 2-3 days. Using a pasteur pipet, the settled zooplankton were transferred to 10 ml vials for long-term storage. The iden-tification of zooplankton was performed to the lowest taxa feasible. 4.2.2 Statistical Analyses The technical specifications of the monitoring program required two types of sampling; con-tinuous and discrete. Data were collected from 0, 1, 2, 3, 4 and 5 m depths for continuous sampling while discrete sampling collected data from 0, 2, 4 and 6 m. The continuous data stations were 121, 132, 221, 241 and 243 and-the discrete stations were 111, 211, 212, 223 and 231. In order to compare all stations the common depths (0,2 and 4 m) were used for ' statistical analysis. The data were analyzed using an ANOVA and a Tukey's w-procedure Test (alpha =0.05). Due to ice cover in February, only stations lil,121, 132, 211 and 212 were sampled. For the~ remainder of the year data were collected at all stations. gs An ANOVA of the zooplankton density by date by station (_) was performed on both continuous and discrete data. These results were then placed into statistically significant groups using the Tukey's w-procedure. Stations that were not sig-nificantly different were grouped together by a horizontal line. A space separating two lines indicates that the two groups are statistically different. It is possible for two groups to overlap and a station may be included in two or more groups. Finally a comparison of zooplankton densities per month was made. 4.3 Results and Discussion The ANOVA of zooplankton data for date by station is summarized in Table 4.3.l. A Tukey's Test statistically grouped and ordered the stations by de-creasing mean density. Station 212 had the highest mean density for almost the i complete year. *1978 was similar in that station 212 was numerically dominate (VEPCO,1978), but in 1979 station 221 showed the highest mean density (VEPC0, 1979). In 1980 sta-tion 212 had the highest mean density 8 times out of 15 samplings. It was in the highest Tukey's grouping 13 out of 15 samplings (Table 4.3.1). Abundi,-* of zooplankton (in terms of total numbers) in ! 1980 was lu.lely due to the Rotifera population, which made up approximately 88% of the total zooplankton population for (_) l 4-3
~
l
- o TABLE 4'.3.1 TUKEY'S w-procedure TEST OF ZOOPLANKTON DATA, DATE BY STATION LAKE ANNA, 1980 JAN 212 221 121 111 241 243 132 231 211 223 FEB 21 2 121 132 111 211 MAR 212 241 231 221 121 111 243 132 223 211 APR 243 121 241 132 111 231 221 212 211 223 MAY 211 21 2 243 231 241 132 221 121 111 223 t
JUN1 211 -212 2,21 243 231 111 121 132 241 223 JUN2 212 211 221 132 243 231 241 111 223 121 () JUL1 212 211 223 132 231 241 221 121 l 'i l 243 JUL2 212 211 223 231 221 111 243 121 241 132 AUG1 212 211 223 221 132 243 111 121 231 241 AUG2 223 221 211 132 231 243 212 241 111 121 SEP 212 211 221 231 121 111 241 132 245 223 OCT 132 211 912 221 231 223 241 111 121 2/3
- NOV 221 132 111 212 121 231 243 223 241 111 DEC 211 221 223 111 241 231 212 121 132 ~243
() 4-4 l
,--w- - *,
1980. Copepoda contributed 8% while Cladocera, contributed l the remaining 4% (Data Base). Compared with 1979 Rotifera increased from 83%, Copepoda decreased from 12% and Cladocera decreased from 5%. (VEPC0,1979). While sheer numbers of Rotifera may be impressive, it is suggested by Hutchinson that in terms of biomass and-hence biological importance the Rotifera population may be insignificant (Hutchinson, 1967). A comparison of relative abundance of zooplankton by month showed MAY and JUN1 to have the highest density per liter with 1672. organisms /1 and 1285 organisms /1 respectively (Ta,ble 4.3.2). This corresponds with an expected increase in , numbers along with a growing phytoplankton populations. The months which had a particularly low density included October, November and December (all < 155 organisms / liter). This can be - attributed to the cooler weather and declining summer-fall populations. A comparison of relative abundance of zooplankton density by station showed sta' tion 212 and 211 to have particularly higher densities (1081 organisms /l and 885 organisns/1 respec-tively) than the other stations on the lake (Table 4.3.3.). G- This same high diversity at these two stations was evident in U 1979 (VEPCO, 1979) and 1978.(VEPC0, 1978). Stations 211 and 212 had the highest mean levels of total phosphate in 1978 and 1979 (VEPCO, 1978 and 1979)~and 1980 was no different (Table
- 1. 3. 2.1 ) . These levels of phosphate exceed the recommended level of 0.05 mg/l for tributary waters entering a reservoir so as to control accelerated or cultural eutrophication (EPA, 1976). These enriched waters promote algal growth and in turn
; contribute to the high density of zooplankton found at station 223 with 302 organisms /1 (Table 4.3.3). This low value may be -
- - due to acid mine #rainage upstream of station 223. pH values
' as low as 4.2 have been recorded just upstream of station 223 (VEPCO, 1979). A characterization of zooplankton populations of stations 121 and 243 is presented below to compare 1979 and 1980. This offers a description of two open water stations , station 121 in the WHTF and station 243, the first lake station to receive WHTF water. The mean zooplankton density for station 121 peaked during the JUN1 sampling of 1980. The mean density at that time was () 4-5
O O 'O l TABLE 4.3.2 RELATIVE ABUNDANCE RANKING OF ZOOPLANKTON DENSITY BY MONTH, LAKE ANNA, 1980 Month MAY JUN1 JUN2 JUL1 APR JUL2 JAN FEB AUG1 SEP. MAR AUG2 OCT NOV DEC Mean f/L 1672 1285 926.9 824 715 400 388 358 273 264 243 187 152 150 127
?
cn a 9
- TABLE 4.3.3 RELATIVE ABUNDANCE RANKING 0F ZOOPLANKTON DENSITY BY STATION, LAKE ANNA, 1980 1
-Station 212 211 221 243 241 132 231 121 111 223 Mean #/L 1081 885 558 531 458 451 434 418 357 302 O
4 e 4 e O 4-7
p) 1105 zooplankton per liter. Rotifera dominated with Keratella and Polyarthra contributing 838 of the 1105. April was second behind the JUN1 sampling with 1098 zooplankton per liter. This sample was clearly dominated by Polyarthra which contributed 877Hof the 1093. . In 1979 station 121 peaked during she JUN2 sampling with 1040 per liter. Rotifera dominated again with Keratella, Polyarthra and Conochilus contributing 890 of the 1040 organ-isms per liter. Station 243 peaked with a mean density of 1748 zooplankton per liter in May of 1980. This was similar to station 121 in that Polyarthra and Keratella made up 1401 of the 1748. The , second highest month for station 243 was JUN1 with 1430 per liter. This sample was dominated by Keratella which numbered -' 882 organisms per liter. The mean density of station 243 peaked during the JUL1 ,, sampling of 1979 with 1244 zooplankton per liter. As at sta-tion 121, Ratifera was numerically dominant with Keratella and Polyarthra accounting for 971 of the 1244 zooplankton per liter. The next significant grouping included the summer
-(]) months with JUN1, highest at 627 zooplankton per liter. This decrease in mean density is associated with a decrease in Rotifera, especially Polvarthra (Data Base). A master list of all zooplankton genera identified in the reservoir during 1980 is presented in Table 4.3.4.
The effects of thermal loading on the zooplankton popula-
. tion appears to be minimal with two reactors on line. The temperatures at station 111 peaked at 34*C on August 5, 1980.
This is close to the tolerance limit for certain Cladocerans, , which is 33.8 + 2.5*C for 48 and 72 hour periods respectively ! (Carson,1972). Copepoda shows c temperature tolerance : ranging from 3-33*C. This degree of thermal flexibility allows : i it to acclimate to a wide variety of thermal environments ! (Bradely, 1975). ! The depth of the thermal effluent is important in that ; i if it is confined to the surface water, many zooplankton have >
. the ability to select a preferred depth. Depth selection would have to take into account food availability and predator ,
i influences. The result of a higher temperature may be in- i creased metabolic activity and therefore decrease the develop-mental stages of eggs (Gallager, 1974). Temperature plays a critical role in the development of diapausing aggs in C) - ! 4-8
l
~
(
- copepods. Should the adults not survive the winter and not produce subitaneous eggs, then the spring cohort would re-sult from overwintering, diapausing eggs. This would not necessarily change the generic richness, only the type of copepod eggs that reach maturity (Cooley, 1978). ;
A study of temperature verses zooplankton densities in Lake Erie showed that cladocerans, copepods and total zooplank-L ton correlated highly to temperature. In the same study zoo-i plankton density and biomass were compared with primary productivity, fish biomass and density, oxygen concentration, temperature, particulate organic carbon and suspended solids. ; The three _that corelated best to zooplankton density were i primary productivity, fish biomass and density and oxygen concentration (Nalepa, 1970). ,
; While direct monitoring of zooplankton productivity was ~
not performed in this study, it is known that filter-feeding zooplankton are more productive than predaceous zooplankton (Wetzel, 1975). This is significant in that 88% of the zoo-plankton present in 1980 were rotifers, which are in large part filter-feeders. Filter-feeding zooplankton are known to correlate directly with primary productivity (Wetzel, 1975) and with little significant change in primary productivity in (]) 1980 it may be that the numbers of herbivorous zooplankton did not change appreciably. This is supported by the fact that there is no significant change in the total zooplankton numbers from 1978 to 1980. The zooplankton community in Lake Anna can be divided into two feeding classes: filter-feeding and raptorial ' (piercing). The majority of rotifers are filtering or sedi-menta'ry suspension feeders, as are the cladocerans and calanoid copepods (Hutchinson, 1967). The few raptorial types ' include cyclopoid copepods and rotifers such as Asplanchna, Ascomorpha and Synchaeta. Trophic relationships can be chaeacterized by the feeding types. Among the Rotiferr, there are fine detrital filter-feeders such as Filinia and Conochilus and live algal filter-feeders such as Polyarthra. Filter-feeding cladocerans and copepods tend to be larger and live longer than the rotifers and therefore influence the food availability for other filter-feeders. The raptorial copepods and rotifers represent tne predaceous input of zooplankton trophic relationships (Hutchinson, 1967). The zooplankton population of Lake Anna has all the above feeding types present in the water column. O 4-9 _~
l l O The filter-feeders are numerically dominant which is evident by the fact that 88% of the zooplankton are rotifers. It follows that a lower number of predaceous zooplankton should exist at the trophic level above herbivorous zooplankton, and is demonstrated in that 8% of the population were copepods (Data Base). 4.4 Summary Characteristics that occurred in Lake Anna zooplankton
'n both 1979 and 1980.
. 1. Stations 211, 212 and 221 had the highest mean densities of zooplankton.
- 2. Rotifera were numerically dominant.
- 3. Stations 223 and 111 showed consistantly lower numbers of zooplankton compared to other stations.
O e I i 4-10 l
-------_____l_---- -. -- - , -
() , 1 TABLE 4.3.4 ZOOPLANKTON MASTER LIST FOR LAKE ANNA, 1980. Phylum Rotifera Class Monogononta Order Ploima Family Brachionidae Genus Brachionus { Kellicottia I Keratella ,- Lepadella i Family Lecanidae Genus Lecane Monostyla ! () Family Notommatidae ! Genus Cephalodella Family Trichocercidae l Genus Trichocerca ! Family Gastropidae Genus Ascomorpha G'stropus a Family Asplanchnidae Genus Asplanchna l Family Synchaetidae . Genus Polyarthra Synchaeta Pleosoma , ' Family Conochiloidea Genus Conochilus Collotheca i 4-11
CZ) TABLE 4.3.4 (Continued) ZOOPLANKTON MASTER LIST FOR LAKE ANNA, 1980 Order Flosculariaceae Family Testudinellidae Genus Filinia Family Hexarthridae Genus Hexarthra Phylum Arthropoda Class Crustacea Order Cladocera Family Sididae Genus Diaphanosoma [} Family Holopedidae l Genus Holopedium Family Daphnidae Genus Ceriodaphnia Daphni,3 $ Family Bosminidae Genus Bosmina Order Copepoda Suborder Calanoida Suborder Cyclopoida O 4-12
1 U 4.5 Reference Bradely,-B.P. Adaption to copepod populations of thermal stress. College Park, MD. Water Resources Research Center; 1975.- Carson, D. M. Geographical variation in upper thermal tolerances of a planktonic cladoceran. Ithaca, New York. Cornell University; 1972. Cooley, J. M. The effect of temperature on the development of diapausing and subitaneous eggs in several fresh-water copepods. Crustaceana 35, vol .1; 1978. Edmondson, W.T., editor. Fresh-water biology, 2nd ed. New . York: John Wiley & Sons, Inc.; 1959. Gallager, B. J. Lake Sangchris: Case History of an Illinois Cooling Lake. Proceedings of a Symposium on Energy Production and Thermal Effects. Ann Arbor, Michigan. Science Publishers, Inc.; 1974. Hutchinson, G. E. A Treatise on Limnology. Vol. 2. New York: () John Wiley & Sons, Inc..; 1967. McMahon, J. W.; Docherty, A. E. Effects of heat enrichment on species succession and primary production in freshwater plankton. Proceedings of a symposium on the environmental effects of cooling systems at nuclear power plants. Vienna, Austria. International Atomic Energy Agency; 1975. Nalepa, T. F. An ecological evaluation of a thermal discharge: Part III: The distribution of zooplankton along the western shore of Lake Erie. East Lansing Michigan. 1 Institute of Water Research Center, University of Michigan; 1972. Nuclear Regulatory Commission. Environmental Techical Specifi-cations for Virginia Electric and Power Company North Anna Power Station, Units 1 and 2. Appendix B Nos. 50-l 338, 50-339. 1977. Located at Virginia Electric and Power Company, Richmond, Virginia. l Pennak, R. W. Fresh-water invertebrates of the United States. New York: The Ronald Press Co.; 1953. O 4-13
l l O l Rutter - Kolisko, A. Plankton rotifers, biology and taxonomy. Dietenheim, Germany: Gebruder Ronz; 1974. Virginia Electric and Power Company. Environmental Study of Lake Anna, Virginia: January 1,1978 - December 31, 1978. A report of James R. Reed and Associates, Inc. to the Virginia Electric and Power Company. March 1979. Located at Virginia Electric and Power Company, Richmond, Virginia. Virginia Electric and Power Company. Environmental Study of Lake Anna, Virginia: January 1, 1979 - December 31, 1979. A report of James R. Reed and As.ociates, Inc. to the Virginia Electric and Power Company. March 1980. Located at Virginia Electric and Power Company, Richmond, - Virginia. Wetzel, R. G. Limnology. Philadelphia: W. B. Saunders Company 1975. O I i l O-4-14
l i f O 5.0 Macrobenthos Studies 5.1 Introduction The objective of the sampling program for macroinvertebrates in Lake Anna during 1980 was to provide data to evaluate the effects of operation of the North Anna Power Station upon this element of the aquatic community. Biological information including dominance, f requency of occ- ' urrence and diversity of the benthic organisms wer.e considered. 5.2 Methods The locations of the benthic stations were in accordance with North Anna Environmental Technical Specificat-ions and are shown in Figure 5.2.1. Individual station descriptions are as follows: () Station A - This station is located in the Sedges Creek Arm of the WHTF. The bottom at 2 meters is firm clay with a shal:ow isyer of sediment and detritus and a considerable amount of submerged aquatic vegetation, of ten completely covering the baskets and transect line. At 4 and 7 meters the bottom is also firm clay but with little sedimentation evident. Current is noticeable at all three depths but is more pronounced at the 4 and 7 meters. Station B - This station is located in the Elk Creek Arm of -the WHTF. The bottom at all three depths is firm clay, with soon submerged aquatic vegetation at 2 meters, although not as much as 2 meters, at station A. There is no noticeable current at this station. Station C - This station is located in the Coleman Creek Arm of the WHTF. The substrate at this station is unlike that found at any of the other stations. Tnere is a considerable i amount of detritus at 2 meters with a lesser amount being pre-sent at 4 and 7 meters. The bottom is strewn with boulders and Current is noticeable at all depths rocks at all three depths. and is stronger here than at any other station. Station 0 - This station is on the southern' side of the Lower Reservoir and near the dam. The substrate at this station 1
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p Nj is very had clay with little or no sedimentation at any depth. There is often a noticeable current at seven meters. Station E - This station is located on the northern shore of the Lower Reservoir across from Duerson Point. Substrate at this station is of moderate firmness and is composed of gravel and soil. The slope is steeper at this station than any of the others. There is no noticeable current at this station. Station F - This station is located on the western shore ' of the Lower Reservoir across from Sturgeon Creek. Substrate at this station is firm clay with some gravel. Station H - This station is located on the southwestern shore of the Uppor Reservoir just downstream from Marshall Creek. The bottom at 2 meters is gravel and granular clay. At 4 and 7 meters the bottom is fira clay with some sedimentation. Station J - This station is located on the northeastern shore in the Pamunkey Arm of the Upper Reservoir just downstream from the 719 bridge. The bottom at 2 meters is clay gravel and silt, at 4 meters is clay and silt and is deep silt at 7 meters. () Station K - This station is located on the northern shore in the North Anna Arm of the Upper Reservoir just downstream from the 719 bridge. The substrate at 2 meters is soil and clay and becomes progressively more silty at 4 and 7 meters. Divers located these stations by lining up specific lans-
-arks and swimming out from shore until crossing the 2 metes transect line. These transect lines were nylon rope placed at the 2, 4 and 7 meter contours. The lines were held in place 0.5 meter or less off the bottom with wooden stakes, located approximately 5 meters apart, which also ierved as markers for the placement of the artificial substrate t amplers. All three transect lines were connected at one end with another length of rope resulting in what appeared to be a large underwater E, (Figure 5.2.2). This line enabled the divers to swim directly from the 2 meter line to the 4 and 7 meter transect lines.
l The arti'fic131 substrate was 3M Corporation No. 200 l Conservation Webbing, which is no longer available. Four 10.2 l cm squares were placed in baskets made from 2 quart round plas-tic containers with lids. These containers were 11.4 cm tall with a diameter of 16 cm at the top and 13.5 cm at the bottom. A total of twenty-two (22) 3.8 cm holes were cut in the top, bottom and sides of each basket. Two baskets containing the substrate were placed on the bottom in the vicinity of each 5-3
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Figure 5.2.2. Diagram of a Typical Benthic Station.
O wooden stake and were held in place by one or more cross shaped stakes. The long arm of the cross was pushed into the
' bottom until the other arm rested firmly on the top of the basket.
.All of the substrate baskets for the entire year were
, put in place over a 3-5 day period during the first part of September. Colonization of the substrate took place over the next 6-8 week period. The first samples were collected in November and monthly thereafter. After divers located the samples, they were very care-fully placed in muslin bags. An overhand knot was then tied
- around the neck of the bag to help prevent the escape of
- organisms during transport.
At the surface, samples were placed in large plastic trash cans, with a minimum amount of water to keep the samples moist but not covered. It was found if the samples t were completely covered with water and left overnight that the dissolved oxygen would be depleted and many of the organisms would die. This problem was lessened in the moist environment. {) In addition to the artificial substrate samples, one O-frame kick sample was taken at each station in 0.5 meter of water near the shore by having someone shuffle their f iet while walking backwards, dislodging the organisms fro.T. ;he i various substrates (Reed, 1977). The organisms were col i lected in the net which was held flush with the bottom .nd fairly close to the feet. [ i
. The day after collection, the entire contents of the r bags were washed through a 0.5 mm sieve. The webbing and i sieved materials were covered with 90% isopropanol in quart containers. For sorting, the materials were placed in enamel pans and flooded with a salt solution (Nacl sp. gr. -l .12 ) l which caused the organisms to float to the surface. All materials and webbing were examined under magnification to i
insure maximum retrieval. The organisms wero identified to r genus or species, whenever possible using the following keys -4 Edmondson (1959), Pennak (1953), Torre-Bueno (1978), Usinger (1956) and Wiggins (1977). 5.3 Results 5.3.1 Sample Collection In 1980 macrobenthic samples were collected at the 9 s'ations in Figure 5.2.1. Monthly samples () 5-5 l 9
() were collected at each station except the following:
- 1. February - station A, B and C collected, stations D-K inaccessable due to ice cover on the lake.
- 2. March - No stations , sere sampled due to a major snow storm which made =ccess to the lake impossible within the three j leeway given to the sam-pling dates.
- 3. September - All stations were collected but approximately 10% of the samples were lost in a transport-ation accident.
- 4. Miscellaneous "Non data" spots, are due either to the absence of macroinvertebrates or vandalized substrate baskets.
5.3.2 Density and Percentage Composition Comparison of 1980 data with Data from 1979 (VEPC0, 1979) shows a continued in-crease in benthic numbers by approximately 2 fold. Table 5.3.2.~1 is a taxonomic list of all organisms collected in (s) 1980. In the reservoir the highest densities were seen in the late fall through the winter months, the densities then de-clined from spring to late summer. This trend is primarily dependent on the chironomid population which traditionally declines in the warmer months. Thp density in the lower . reservoir (stations D, E and F) was not significantly higher in 1980 than 1979 (Student's T-Test, * = .05), the Upper Reservoir (stations H, J and K) al30 showed no significant increase at * = .05 (Table 5.3.2.2). In 1980 densities in the WHTF did not show any significant increase from 1979 levels (Student's T-Test S- = .05), however actual numbers of organisms collected increased by a factor of 2.5. The increase was due primarily to the large numbers of Corbiculidae collected. Corbiculidae has become the dominant macroinvertebr&te in the WHTF (representing 76.7 % of all benthics collected in the WHTF), and the Lake system as a whole (representing 42.5% of all organisms collected in the lake). Chironomidae remains the dominant macroinvertebrate in the Reservoir (representing 52.3% of all benthics collected in the Reservoir) but not in the lake system as a whole (representing 23.3% of all organisms collected in the Lake Anna). 5-6
l l O : 1 1 TABLE 5.3.2.1 TAXONOMIC !(ST OF MACR 0 BENTHIC ORGANISMS COLLECTED .Il LAKE ANNA, 1980 Phylum: Platyhelminthes Class: Turbellaria Phylum: Annelida < Class: Hirudinea Class: 011gochaeta . Phylum: Mollusca Class: Gastropoda Order: Pulmonata Family: Physidae Physa sp. Family: Planorbidae ] [} , Helisoma sp. Class: Pelecypoda Order: Heterodonta Family: Sphaeriidae Family: Corbiculidae , Order: Eulamellibranchia Family: Unionidae Phylum: Arthropoda Class: Crustacea , Order: Isopoda Family: Asellidae Asellus Order: Amphipoda Family: Talitridae Hyalella azteca Family: Gammaridae
- Crangonyx sp.
O 5-7 1
TABLE 5.3.2.1 (Continued) TAXONOMIC LIST OF MACR 0 BENTHIC ORGANISMS COLLECTED IN LAKE ANNA, 1980 3 Order: Decapoda
- . Family
- Palaemonidae Palaemonetes sp.
Class: Insecta Order: Ephemeroptera Family: Ephemeridce , Hexagenia munda Family: Caenida Caenis amica Family: Ephemerellidae Ephemerella sp. Family: Tricorythidae (]) Tricorythodes sp. Family: Heptageniidae Stenonema sp. Order: Odonata m Suborder: Anisoptera. . Family: Gomphidae Progomphus Dromogomphus spinosus Hagenius brevistylus Family: Libellulidae Epicordulia princeps > Neurocordulia sp. Family: Macromiidae Macromia sp. Didymops sp. l 5-8 1 l _ _ _ _ . _,
l O V TABLE 5.3.2.1 (Continued) TAXONOMIC LIST OF MACROBENTHIC ORGANISMS COLLECTED IN LAKE ANNA, 1980 Suborder: Zygoptera Family: Coenagripnidae Argia sp. Enallgama sp. Ischnura sp. , Order: Plecoptera Family: Nemouridae Brachyptera sp. Order: Megaloptera i Family: Stalidae Sialis sp. {) Order: Coleoptera Family: Psephenidae Family: Staphylinidae i Family: Haliplidae Order: Trichoptera Family: Polycentropodidae Cyrnellus fraternus Nyctiophylax affinis Phylocentropis placidus Family: Hydroptilidae Hydroptila sp. Orthotrichia sp. Family: Leptoceridae i Setodes sp. Oecetis sp. Mystacides sp. Triaenodes sp. O 5-9
O
' TABLE 5.3.2.1 (Continued) TAXONOMIC LIST OF MACR 0 BENTHIC ORGANISMS COLLECTED IN LAKE ANNA, 1980 Order: Diptera Family: Culicidae Subfamily: Culicinae Chaoborus sp.
Family: Chironomidae , 1 1 O 1 i \b 4 O 5-10
,c\
LJ TABLE 5.3.2.2 DENSITY AND PERCENTAGE COMPOSITION OF DOMINANT MACR 0BENTH05 IN LAKE ANNA IN 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. VALUES IN PARENTHESES ARE PERCENT COMPOSITION. AN ASTERISK (*) DENOTES LESS THAN 1%. Jan. Feb. Res. WHTF Res. WHTF Corb*"slidae 6.00 95.56 - 104.61 (4.0) (60) (-) (71.6) Chironomidae 104.78 16.56 - 16.44 - (70.3) (29.8) (-) (11. 7 ) Cyrnellus fraternus 15.25 17.22 - 7.78 (10.2) (10.8) (-) (5.5) Sphaeriidae 5.42 -
. 2.5 (3.6) (-) (-) (1.9)
( Polycentropis sp. 6.14 20.22 - 5.94 (4.1) (12.7) (-) (4.2) Hya11ela azteca 8.69 4.89 - - (5.8) (3.2) (-) (-) 1 Crangonyx sp. - - - - , (-) (-) (-) (-) Hexagenia munda .69 .78 - .94 (*) (*) (-) (*) Argia apicalis .44 .44 -
.39
(*) (*) (-) (*) Turbe11 aria .89 - -
.06
(*) (-) (-) (*) Ena11gama basidens .22 1.56 - .94 l (*) (*) (-) (*) l ! All Others .61 1.28 - .61 (*) (*) (-) (*)
' Total Organisms 5369 2863 (-) 2524 O
5-11
l O TABLE 5.3.2.2 (Continued) DENSITY AND PERCENTAGE COMPOSITION OF DOMINANT MACROBENTH0S IN LAKE ANNA IN 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. VALUES IN PARENTHESES ARE PERCENT COMPOSITION. AN ASTERISK (*) DENOTES LESS THAN 1%. Mar. Apr. Res. WHTF Res. WHTF Corbiculidae - - 4.56 179.28 (-) (-) (4.9) (78.9) . Chironomidae - - 64.83 20.56 (-) (-) (70.2) (9.0) Cyrnellus fraternus - - 10.67 15.67 (-) (-) (11. 5 ) (6.9) Sphaeriidae - - 3.75 2.0 (-) (-) (4.1) (*) Polycentropis sp. - - 3.25 6.44 (-) (-) (3.5) (2.8) Hyallela azteca - - 2.58 .17 (-) (-) (2.8 (*) Crangonyx sp. - - - - (-) (-) (-) (-) Hexagenia munda - - 1.08 1.11 (-) (-) (1. 2 ) (*) Argia apicalis - - .67 .5 (-) (-) (*) (*) Turbe11 aria - -
.22 -
(-) (-) (*) (-)
.Ena11gama basidens - - - .5
(-) (-) (-) (*) All Others - - .75 1.17 i (-) (-) (*) (*) l Total Organisms - - 3325 4089
.O (-) (-)
5-12 l
() TABLE 5.3.2.2 (Continued) DENSITY AND PERCENTAGE COMPOSITION . 07 DOMINANT MACR 0BENTH0S IN LAKE ANNA IN 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. VALUES IN PARENTHESES ARE PERCENT COMPOSITION. AN ASTERISK (*) DEN 0TES LESS THAN 1%. May Jun. Res. WHTF Res. WHTF Corbiculidae 4.94 350.94 10.86 28.5 (5.6) (85.4) (18.0) (36.1) Chironomidae 54.0 6.22 25.06 10.94 (61.2) (1.5) (41.5) (13.6) Cyrnellus fraternus 14.0 29.78 7.03 2.64 (15.9) (7.3) (11.7) (6.7)- Sphaeriidae 4.44 1.17 5.11 13.25 . (5.0) (*) (8.5) (33.5)
.(])
Polycentropis sp. 5.14 19.83 7.92 3.39 (5.8) (4.8) (13.1) (9.4) Hyallela azteca 2.5 .06 1.31 .11
- (2.8) (*) (2.2) (*)
Crangonyz sp. -
.17 - .06
(-) (*) (-) (*) Hexagenia munda .69 .67 .39 .44 (*) (*) (*) - (*) Argia apicalis .89 .6' .58 .5 (1.0) (*) (*) (*) Turbe11 aria .39 - 1.5 - > (*) (-) (2.5) (-) , Ena11gama basidens .14 .67 - - (*) (*) (-) (-) All Others 1.08 .44 .56 .28 (1.2) (*) (*) (*) Total Organisms 3176 7391 2171 1429 fw
-\) ,
5-13
J. O TABLE 5.3.2.2 (Continued) 6ENSITY AND PERCENTAGE COMPOSITION OF DOMINANT MACROBETH0S IN LAKE ANNA IN 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. VALUES IN PARENTHESES ARE PERCENT COMPOSITION. AN ASTERISK (*) DEN 0TES LESS THAN 1%. Jul. Aug. Res. WHTF Res. WHTF Corbiculidae 5.97 103.61 5.31 59.11 (9.7) (69.9) (10.8) (64) - Chironomidae 15.69 5.72 8.56 1.56 (25.5) (3.9) (17.4) (1.7) i Cyrnellus fraternus 15.53 31.89 2.22 29.33 (25.3) (21.5) (4.5) (31.8) e Sphaeriidae . 20.06 2.06 30.81 1.06 (32.6) (1.4) (62.7) (1.1) Polycentropis sp. 2.58 1.5 .47 .39 (4.2) (2.4) (*) (*) Hyallela azteca .31 -
.06 -
(*) (-) (*) (-) Crangonyx sp. - - - - (-) '(-) (-) (-) Hexagenia munda .31 .28 -
.06
(*) (*) (-) (*) Argia aoicalis .06 - -
.11
(*) (-) (-) (*) Turbe11 aria - - .11 - (-) (-) (*) (-) Enallgama basidens .03 - .03 .06 (*) (-) (*) (*) All Others 1.03 1.22 1.81 .78 (1.7) (*) (3.7) (*) , O Totai orsaats=s 2213 2659 1770 1664 5-14 I L
O 1 TABLE 5.3.2.2 (Continued) DENSITY AND PERCENTAGE COMPOSITION 0F COMINANT MACROBENTH0S IN LAKE ANNA IN 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. VALUES IN PARENTHESES ARE PERCENT COMPOSITION. . AN ASTERISK (*) DENOTES LESS THAN 1%. Sep. Oct. Res. WHTF Res. WHTF Corbiculidae 14.78 151.0 Colonization . (24.6) (89.9) Period Chironomidae 19.89 2.5 (33.1) (1.5) - Cyrnellus fraternus 5.78 12.72 (9.6) (7.6) () Sphaeriidae 16.22 (27.0) (-) Polycentropis sp. .69 .61 (1.2) (*) Hyallela azteca - - (-) (-) Crangonyx sp. - - (-) (-) Hexagenia munda .19 .11 (*) (*) Argia apicalis .31 .22 (*) (*) Turbe11 aria .06 - (*) (-) Enallgama basidens -
.06
(-) (*) All Others .89 .72 (1.5) (*) () Total Organisms 2161 3023 5-15
TABLE 5.3.2.2 (Continued) DENSITY AND PERCENTAGE COMPOSITION OF DOMINANT MACR 0BENTH0S IN LAKE ANNA IN 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. VALUES IN PARENTHESES ARE PERCENT COMPOSITION. AN ASTERISK (*) DENOTES LESS THAN 1%. Nov. Dec. Res. WHTF Res. WHTF Corbiculidae 69.47 498.0 63.89 345.67 . (27.3) (76.9) (34.4) (81.4) Chironomidae 145.25 11.94 85.14 7.56 (57.1) (1. 8 ) (45.9) (1. 8 ) Cyrnellus fraternus 26.69 126.61 19.09 62.61 (10.5) (19,5) (10.3) (14.8) O SPaaeriidae - (-) (-) (-) (-)
-Polycentropis sp. 9.75 7.0 5.31 5.78 (3.8) (1.1 ) (2.9) (1.4)
Hya11ela azteca .17 .06 - - (*) (*) (-) (-) . Cranconyx sp. 1.39 - 8.33 .11 (*) (-) (4.5) (*) Hexagenia munda .94 .72 1.28 .44 (*) (*) (*) (*) 4 Areia apicalis .42 .83 .78 .67 ( (*) (*) (*) (*) i Turbe11 aria .14 - .08 - (*) (-) (*) (-) Ena11gama basidens .08 .5 .39 .28 (*) (*) (*) (*) All Others .28 2.11 1.47 1.44 l (*) (*) (*) (*) Total Organisms 9165 11,663' 6684 7640 1 5-16
g O The two year emergence of Corbiculidae into the dominant macroinvertebrate in the lake system may represent the begin-ing of ecological and economic problems (VEPC0,1979). 5.3.3 Diversity Diversity values for 1980 were calculated for all stations using the Sequential Comparison Technique (Cairns and Dickson, 1971). Diversity values were similar to those reported in 1979 and ranged from 1.00 to 0.01. Over-all diversity remained the same as tnose in 1979. In the Data Base the category entitled " number of taxa with greatest abundance" is defined as the smallest' number of taxa necessary to account for 50% or more of the total number of organisms. 1980 was the first time this value has exceeded 2 at any depth at any station. . 5.3.4 Horizontal Distribution The horizontal distribution of the dominant macrobenthos is summarized in Table 5.3.4.1. Chironomidae, Cyrnellus fraternus (Trichoptera) and Argia apicalis (Odonata) were found at all stations in 1980 which is similar to the 1979 patterns with the exception that the Ephemeropterans were not found at all stations in 1980. Corbiculidae (Pelecypoda), Hyallela azteca(Amphipoda), () Crangonyx sp. (Isopoda-) and Turbellaria were found at more stations in 1980 than in 1979. The number of Chironomidae were up at stations A, C and K while they dropped at the remaining stations. As in 1979 (VEPCO, 1979) Cyrnellus was the dominant Trichoptera in 1980 with its greatest density appearing at station C which provides a high quality habitat (VEPCO, 1979). The Odonata were represented primarily by Argia acicalis and to some ex- - tent by Enallgama basidens. Dersity val'Jes were up at 6 out of 9 stations when compared to 1979 while the remaining three dropped. 5.3.5 Vertical Distribution Vertical distribution of the eleven major macrobenthic taxa is shown in Table 5.3.5.1. Eight of the eleven major taxa decressed in density as the depth increased. Included in this trend were: Chironomidae, Sphaeriidae (Polecypoda), polycentropis sp., (Trichoptera), Hyallela ,azteca (Amphipada), Crangonyx sp., (Isopoda), Hexagenia munda (Ephemeroptera), Turbellaria and Enallgama batiaens (Odonata) Turbellaria, Ephemeroptera and Odonata are the only three orders which have consistantly followed this pattern for the last 6 years. Corbiculidae increased in density as depth increased. Cyrnellus fraternus (Trichoptera) l (a~) ! 5-17
Qd Ov
. v(3 1-TABLE 5.3.4.1 HORIZONTAL DISTRIBUTION OF DOMINANT MACROBENTH0S IN LAKE ANNA, 1980.
DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. AN ASTERISK (*) DENOTES LESS THAN 0.1 ORGANISMS / SAMPLER WHTF Stations , Reservoir Stations Taxa A B C D E F H J K Corbiculidae 80.28 2.93 491.67 58.89 12.20 21.70 23.80 3.72
- Chironomidae 8.31 10.52 11.27 4.07 3.76 13.13 14.87 111.30 206.28 m Cyrnellus fraternus 13.75 6.23 81.77 36.54 6.61 10.20 11.63 8.52 3.96 Sphaertidae
- 1.72 7.88 9.65 2.93 11.96 19.24 3.52 9.91 Polycentropis sp. 2.62 17.32 3.53 5.57 6.50 13.43 1.87 *
- Hyallela azteca 1.50 *
- 0.65 0.39 1.69 6.04 0.11 0.80 l Crangonyx sp. * *
- 0.13 0.17 3.24 2.81 *
- Hexagenia munda 0.20 1.32 0.25 0.31 1.72 0.35 0.70 0.56
- Argia apicalis 0.43 0.23 0.32 0.26 0.70 0.67 0.54 0.19 0.46 Turbellaria - * - *
- 0.15 0.89 1.09
- Enallgama basidens 0.92 0.38
- 0.11
- 0.20 * *
- I
j O O o 1 TABLE 5.3.4.1 (Continued) HORIZONTAL DISTRIBUTION OF DOMINANT MACR 0BENTH05 IN LAKE ANNA, 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. AN ASTERISK (*) DENOTES LESS THAN 0.1 ORGANISMS / SAMPLER i J i WHTF Stations Reservoir Stations I A B C D E F H J K l 1.35 0.37 1.18 0.39 0.35 1.15 1.85 0.76 2.02 i All Others 3 6529 2461 35,910 6541 1909 4240 4446 7014 12,085 Total Organisms { 10 10 9 9 9 9 9 9 Months Sampled 10 y ) C i i i 4 1 l 4 .
--~~e-.--~- ..v.m, . . . . , , _ , _ , , . . , . , . _ , _ , , ,
~. _.- - - ._. .
i L e TABLE 5.3.5.1 VERTICAL DISTRIBUTION OF DOMINANT MACR 0BENTH05 IN LAKE ANNA, 1980. DENSITY IS EXPRESSED AS THE NUMBER OF ORGANISMS / SAMPLER. AN ASTERISK (*) DENOTES LESS THAN 0.1 ORGANISMS / SAMPLER. d Taxa 2 Meters 4 Meters 7 Meters Corbiculidae 51.68 83.73 92.13 Chironomidae 50.70 42.32 0.55 - Cyrnellus fraternus 20.05 20.76 13.04 Sphaeriidae 7.87 7.18 6.77 Polycentrop11 sp. 11.29 3.22 2.19 l Hya11ela azteca 0.76 0.14 * {} Crangonyx sp. 0.51 * - Hexagenia munda 0.79 0.40 0.31 Argia apicalis 0.86 0.24 0.40 Turbe11 aria 0.46' O.15
- Ena11gama basidens 0.47 *
- All Others 0.84 0.48 0.64 Total Organisms 24,572 26,676 22,847 i
O 5-20
/~'T U'
were most dense at 4 meters followed by 2 meters and 7 meters. Arara apicalis (Odonata) were most dense at 2 meters follow-ed.by 7 meters and 4 meters. 5.3.6 Surface Community As in 1979, surface samples were collected at all stations using a 0-frame dip net technique and a one minute sampling period. As in past years the density of these samples was quite variable and ranged from 0 to 1413 organisms. In 1980 the community structure remained similar to that of 1979 with the exception of Corbiculidae which has now become the dominant macroinvertebrate in the community. As in 1979 Amphipoda and Trichoptera were most abundant in or near aquatic macrophytes. 5.4 Summary 1 The macrobenthos density did not show any significant increase during 1980 (Student's T-Test oc =.05).
- 2. The actual numbers of organisms collected in 1980 in-creased over 1979 by a factor of 2.5, primarily dae to increased numbers of Corbiculidae.
A
\_/ 3. Corbicula became the dominant macroinvertebrate in the Lake in 1980 although its increase occurred primarily in the WHTF.
- 4. The Ephemeroptera population declined slightly in 1980.
- 5. Isopoda continued to increase in numbers in 1980.
i l l= 5-21 , l l l
i l V,m 5.5 References , Cairns, J., Jr.; Dickson, K.L. A simple method for the bio-logical assessment of the effect of waste discharge on aquatic bottom dwelling organisms. J. Water Pollution
- Coutr. Fad. 43(5):755-772; 1971.
Commonwealth Edison Company. Annual Report For Fiscal Year 1976 Lake Sangchris Proje'ct. A renort by Illinois Natural History Survey to Commonwealth Edison Company. ' February 1977. Located at Commonwealth Edison Company, Chicago, Illinois. Diaz, R. J. Asiatic Clam, Corbicula manilensis (Philippi), . in the Tidal James River, Virginia. Gr.esapeake Science 15(2):118-120; 1974. Edmondron. W. T., editor. Freshwater biology, 2nd ed. New York: John Wiley and Sons; 1959. Goss, L. B.; Cain, C., Jr. Power plant condenser and service water system fouling by Corbicula, the Asiatic Clam. O.~ Biofouling Workshop: Electric Power Researen Institute and Maryland Power Plant Siting Program; 1975 June 16-17; Baltimore, MD. Johns-Hopkins University; 1975. Merr;tt, R. W.; Cumins, K. W., editors. An introduction to the aquatic insects of North America. Dubuque, IA: Kendall/ Hunt Publishing Co.; 1978. Needham, J. G.; Westfall, M. J., Jr. A manual of the dragon-flies of North America ( Anisoptera). Berkeley, CA: University of California Press; 1954. Pennak, R. W. Freshwater invertebrates of the Unite'd States. New York: The Ronald Press Co.; 1953. Reed, J. R., Jr. Stream community response to road construc-tion sediments. Blackeburg, VA; Water Resources Research Center; 1977. I Rodgers, J. H.; et al. The invasion of the Asiatic Clam, Corbicula maniTensis, in the New River, Virginia. The Nautilus Vol. 91(2):43-46; 1977. Sickel, J. B. A new record of Corbicula manilensis (Phillippi) in the southern Atlantic slope region of Georgia. The Nautilus 87(1): 11-12; 1973. () 1 5-22
h s V Sinclair, R. M. Effects of an introduced clam (Corbicula) on the water quality in the Tennessee River Valley. Second Annual Sanitary Engineering Conference; 1963 May 30-31; Nashville, TN. Vanderbilt University; 1965.
; Ison, B. G. Further studies 0:1 the Asiatic Clam-(corbicula) in Tennessee. Nashville, TN. Tennessee Stream Pollution Control Board Tennessee Department of Public Health; 1963 (Reprinted 1978); 78 p. Available from Tennessee Department of Public Health, Nashville, TN.
Torre-Bueno, J. R. De la, F.R.E.S. A glossary of entomology. New York: New York Entomological Society; 1978. , Usinger, R. L., Editor. Aquatic insects of California. Berkeley, CA: University lof California Press; 1956. Virginia Electric and Power Company. Environmental Study of Lake Anna, Virginia: January 1, 1979-December 31, 1979. A reporc of James R. Reed and Associates, Inc. to the Virginia Electric and Power Company. March 1980. Located at Virginia Electric and Power Company, Richmond, (]) Virginia. Voshell, J. R., Jr.; Simmons, G. M., Jr. The odonata of a new reservoir in the southeastern United States. Odonatologica.7(1): 67-76; 1978. Wiggins, G. B. Larvae of the North American Caddisfly Genera (Trichoptera). Toronto: Univer.sity of Toronto Press; 1977 4 O 5-23
i
,m V
6.0 Fish Studies 6.1 Introduction Studies of fish populations in water receiv-ing heated effluent from power plant discharges have been exten-sively documented and have produced varying results (Bennett and Gibbons, 1975; Marcy, 1976; Bennett and Gibbons, 1974; Larimore and Tranquilli,1977; Gammon,1973; Larimore,1975; Goldstein, ' 1976; Proffitt, 19o9; Neill and Magnuson, 1972). The need for additional information to supplement existing studies is essen-tial to more accurately define the impacts of power plant dis-charges on fish populations. This study is designed to provide information relating to the impact of the North Anna Nuclear Power Plant on the fish community of Lake Anna, Virginia and is carried out in accordance with the guidelines set forth in the technical specifications as promulgated oy the Nuclear Regulatory Commission. (]) 6.2 Methods 6.2.1 Fish Collection Techniques and Station Desinnations Locations of all fish collection sites are shown on Figures 6.2.1.1 and 6.2.1.2. In general, habitats at all stations were similar, although some slight variations did occur. Bottom types varied from submerged brush, decaying vegetation and fallen logs to detritus and clay, Aquatic macrophytes were encountered in some shallow areas anc the shoreline terrestrial vegetation var-ied from open pastures and old fields to near climax deciduous 4 oak forests. Experimental gill nets were set, as often as conditions allowed, near littoral drop off areas where, as dis-covered from previous sampling, fish tend to move more frequently. Depth selection was aided by a Ray Jefferson depth sounder (Model 5270) to standardize the depth at each separate sampling period. During periods of thermal stratification, nets were set above the thermocline which usually ranged from six to eight meters in depth. Generally, the best possible habitats were exploited at each station depending on time of year, weather conditions, and other physical and chemical factors. All sites l in the reservoir were similar except Contrary Creek which was l (s / 6-1
o g a'(
- 4 e
T _ l -- kTuI
- e N
2i s V r e mt e 8 0 o 2 0.E. 1 l i m t R n 2KK ri o s et n wa i o
. ot t PS a
t i f O n i g n t t e 1 1 l l Zi. i g , f
, o.
0 n8 Y o9 i1 t aa cn on lA l e ak ra eL n en Gi 1 . 1 2 _ 6 e , O i r u g F _ T~ _ 1 . J
l O O O 2 1 0 2 MD C Kilometers Pamunkey\ Ceek N 1 ( ' NAR ! Arm I l Rt 208 I "Mid Reservoir m b I Power # Station Dam Cove i / Millpond Creek Figure 6.2.1.2 General location of rotenone stations in Lake Anna 1975 - 1980 Moody Creek
I O: E notably different due to a greater transparency of the water and lower alkalinity and pH values than other areas of the reservoir. Collecting methods. included the use of experimental gill
nets that were 91.44 m in length and 1.83 m deep. Each net consisted of.six panels 15.24 m long with respective mesh sizes of 1.27, 2.54, 3.81, 5.08, 6.35 and 7.62 cm bar mesh. One net was set at each station on a quarterly basis.
Gill nets tend to be selective and are more efficient in capturing fish with external roughness, teeth, spines, etc., (Lagler,1968). and they tend to catch larger fish (Yeh,1977). Fishing success of passive nets depends on fish movements and , i their efficiency and selectivity may be subject to abrupt
- changes from shifts in barometric pressure, wind, and currents F (Lagler,1968). The limitations of collection methods were con-sidered when the data were analyzed. Several samples were taken and the mean catch reported and compared between sites. The use i of experimental gill nets with varying mesh minimized the sam-
- pling bias. No matter what type of sampling techniques is g g_ employed, each has its own degree of selectivity depending upon
(_) the situation (Lagler, 1968). Therefore, in this study a variety of techniques were used including seines and electro-fishing. Electrofishing was done using a pulsed D.C. boat shocker. These samples were taken prior to and during the spawning period of the largemouth bass to obtain information relating to the reproduction of this tish and also to supplement age and growth data. Bass were collected from the Reservoir and the WHTF during the same day to reduce bias. Cove rotenone samples are taken in August, 1980 to obtain information on standing crop, young of the year and population i structure. Six coves were selected, surveyed and blocked off with~a 300' x 25' x t" blocker net. Divers were sent down to ensure the net was secure on bottom. 100-125 fish were collect-
- ed by electrofishing, fin clipped, recorded and released inside
! the blocker net to facilitate a tag return estimated to test the effectiveness of the rotenone. Rotenone was added at a
-concentration of one part per million and the fidi were col-1 lected, measured, sorted by size class and weighed. , 6.2.2 Water Quality Analyses Selected physical and chemical measurements were performed at the time the fish collections were made. Interpretation of these data were discussed in relation to the fisheries data.
! 6-4 I
(v Temperature and dissolved oxygen were taken at one meter intervals throughout the water column at each station with a Yellow Springs Instrument Company Model 54 dissolved oxygen / temperature meter. Alkalinity (CACO,) and hardness (EDTA) i were measured at the surface, mid and bottom depths (Standard , Methods, Amer. Publ. Health Assoc. et. al., 1975). Turbidity I I was monitored at the surface, mid and bottom depths utilizing a Coleman Nephecolorimeter and recorded in nephelos units (NTU) (Amer. Publ. Health Assoc. et.al., 1975). 6.2.3 Abundance and Distribution of Populations Changes in relative abundance and species composition were based upon a standardized netting program as well as summer rotenone samples. Rotenone provided information on standing crop as well as young of the year fishes and species composition. This method in con-junction with the standardized netting program has proven to be effective in obtaining valid information concerning the abundance and distribution of fish populations in Lake Anna. Relative abundance values were determined based on catch per unit fishing effort (c/f), on the basic assumption that unit effort can be calculated on any method as long as effort (f) is' O in the same units, and is most commonly used for making year to year comparisons as part of a monitoring program (Lackey, 1974). Catch per net day (c/f) for samples obtained from experi-mental gill nets provided the basis for determining changes in the relative abundance of fish species. One net day was equiv-alent to 91.44 meters of experimental gill net set for one over-night period (approximately 18-20 hours). Relative abundance
~
values were calculated on the basis of numbers of individual species and weight of individual species. In addition to providing supplemental information on relative abundance, the rotenone samples were analyzed for standing crop (biomass or kg/ hectare). Standing crop was based on a tag return estimate utilizing a mark and recapture technique and was calculated us-ing surface area. From these data, individual species weight and numbers were multiplied by a correction factor to obtain the estimated standing crop (kg/ hectare). 6.2.4 Age and Growth of Largemouth Bass, Micropterus salmoides. . Age and growth of Micropterus salmoides from the Lower Reservoir and WHTF were evaluated from individuals collected throughout the study period. Upon capture, individuals were weighed, a measure of total length was taken using a conventional fishery measuring board, and scale samples were collected. Total length (T.L) (as opposed to standard length (S.L.)) was used because it is
- (
! 6-5
/
more representative in length-weight functions (Royce, 1942), is easier to measure in the field, can be measured more accu-rately than S.L. (Carlander and Smith, 1945) and is more commonly used by fishermen and fishery biologists (Ricker and Merriman, 1945). Approximately 12 scales were removed from the shoulder at the lateral line below the origin of the dorsal fin on the left side. Scale samples were placed in an envelope on which date, collection method,-location, weight, length, as well as sex of the fish when noted, were recorded. Permanent mounts of scales were made in the laboratory, and impressions were made by placing scales between two pieces of cellulose acetate, each approximately 0.5 mm thick, and pressed in an Ann Arbor Rollerpress. Age determination of fish and measurements of scales for back-calculation were accomplished with a Bausch and Lomb Tri-Simplex projector at a magnification of 43X. All scales were aged a minimum of two times and at least four scales were ex-I amined from each individual. Regenerated scales were disre-I garded. The method proposed by Hile (1941) designating January 1, as a universal fish birthday was employed in aging. The , formula used for back-calculating of body length is: L' =C+ s' (L -C) where L' = length of a fish when annulus X was formed; L = length of fish at time scale samples was obtained; S' = length of scale radius to annulus X; S = length of total scale radius; C = intercept as calculated from the regression of scale length vs body length. This equation was employed because it accounted for a j greater amount of the variability than other methods attempted. i (Hile, 1941) presents a detailed discussion on various methods of back-calculation of growth and where each should be employed. Other discussions on these techniques and their use with various species of fish have been presented by many authors (LeCren, l 1947; Nicholls,1957; Padfield,1951; Ricker,1969; Bennett, 1937; Weatherly, 1972; Everhart, et. al., 1975; Carlander, 1977). l l O 6-6
~N (d
Compution of weight from length was based ~on the length-weight relationship. - log W = log a + b log L where: log W = pred,1cted log weight log a = y intercept log b = slope of the line log L = actual log length 6.3 Results 6.3.1 Physical and Chemical All physical and chemical data are shown in the Data Base. Temperatures were taken month 13 . one meter intervals at each fish station except where ice cover prevented sampling at some stations in February. Temperatures at the WHTF gill netting stations were generally higher than at the Reservoir gill netting stations (Data Base). Dissolved oxygen levels observed at meter intervals were
.() generally high with corresponding values of saturation at all fish stations throughout the year (Data Base).
Turbidity in the Upper Reservoir stations was higher than all other fish sampling stations. Hardness and alkalinity values were relatively low and'showed no temporal or spatial patterns. 6.3.2 Relative Abundance Based on Gill Net Observations Throughout the sampling period between 1973 and 1980, all fish ! collected utilizing gill nets were counted to facilitate esti-mation of relative abundance in terms of numbers of individuals (Table 6.3.2.1). Beginning in 1975-1980 composite weights were also taken and expressed in terms of kg/ net day to yield data on biomass of fish collected (Table 6.3.2.2). The gizzard shad, Dorosoma cepedianum, was discovered in Lake Anna in 1974 and has increased in gill net catches from 3.1 and 7.3% up to as much as 68% of the catch per net day (Tabl e 6. 3. 2.1 ) . This species has been shown to dominate fish collections in both the hot water and control arms in a cooling reservoir and contributed from 34.5-79.1% of the total catch (Witt, Campbell, and Whitley, 1970). The gizzard shad in Lake Anna has proven to be the dominant fish in terms of numbers, even in years with reduced catch per net day (Table 6.3.1.1). O 6-7
.~ _ . . _ _ _ . _ . . . . ._. _ _ . . _ . _ . _ _ ~ _ . _ _ _ . . . . _ . . . _ . .
O O O TABLE 6.3.2.1 CATCH PER NET DAY AS EXPRESSED IN NtMBERS OF INDIVIDUALS BY SPECIES FROM 1973-1980,. FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total Anguillidae Anguilla rostrata 1973 1974 0.1 0.2 1975 T 1976 os 1977 < 0.1 0.2 1978 1979 1980 Clupeidae I Dorosoma cepedianum 1973 1974 3.5 7.3 4.7 7.3 1.1 3.1 1975 5.3 13.2 10.7 25.0 13.7 31.2 1976 20.8 38.3 18.5 44.1 14.0 27.2 1977 25.4 68.0 13.3 53.8 14.7 42.7 1978 6.9 32.5 18.5 54.6 6.7 25.0 . 1979 5.8 28.3 5.4 25.5 4.2 14.5 1980 14.6 56.4 17.4 47.7 7.8 25.7
~
O O 0-TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NLMERS OF INDIVIDUALS BY SPECIES FROM 1973-1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF TOTAL RESERVOIR TOTAL RESERVOIR TOTAL Esocidae Esox niger 1973 8.4 9.8 6.2 8.5 8.4 8.4 1974 7.1 14.8 3.1 4.8 1.0 2.8 - m 1975 2.8 7.0 1.6 3.7 1.5 3.4 E 1976 2.3 4.2 1.7 4.0 1.2 2.3 1977 1.0 2.6 < 0.1 0.2 0.7 2.0 1978 0.1 0.4 1979 0.2 0.8 0.3 1.5 0.2 0.6 1980 0.1 0.4 0.7 2.0 Cyprinidae Cyprinus carpio, 1973 0.1 0.1 2.4 3.3 8.7 8.7 1974 1.0 2.0 1.5 2.3 0.5 1.4 1975 1.4 3.5 1.4 3.2 1.4 3.2 1976 0.5 0.9 1.3 3.1 1.6 3.1 1977 0.7 1.8 0.8 3.2 1.6 4.7 1978 1.6 7.5 1.9 5.6 0.6 2.2 1979 1.1 5.3 0.8 4.0 1.7 5.7 1980 0.3 1.2 1.5 4.1 0.5 1.6 1
O O O TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES FROM 1973 1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total Notemigonus crysoleucas 1973 40.8 48.0 29.2 40.1 27.2 27.2 1974 1.0 2.0 16.1 25.2 1.1 3.1 1975 0.4 1.0 < 0.1 < 0.1 0.4 0.9
. 1976 0.6 1.1 < 0.1 < 0.1 0.6 1.1 i 1977 0.4 1.0 < 0.1 0.2 2.1 6.1
$ 1978 < 0.1 0.2 0.2 0.6 1979 < 0.1 0.2 1980 < 0.1 < 0.1 Catostomidae Catostomus comersoni 1973 0.2 0.2 1974 1975 0.1 0.2 0.1 0.2 1976 < 0.1 < 0.1 < 0.1 < 0.1 0.8 0.2 1977 < 0.1 < 0.1 0.5 1.4 1978 < 0.1 0.3 1979 1980 0.8 2.6
l O O O (' . l l l TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES FROM 1973-1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF -Total Reservoir Total Reservoir Total Erimyzon oblongus 1973 9.9 11.6 5.5 7.5 12.4 12.4 1974 12.8 26.7 12.8 20.8 3.9 11.1 1975 13.2 33.0 5.5 12.8 5.3 12.1 1976 10.3 18.9 4.2 9.9 5.7 11.0 1977 2.1 5.7 1.3 5.0 2.3 6.7 i'** 1978 0.1 0.4 0.2 0.6
"' 1979 < 0.1 0.4 < 0.1 -0.2 1980 0.1 0.3 Moxostoma macrolepidotum 1973 0.1 0.1 0.1 0.1 1974 0.1 0.1 0.2 0.5 1975 0.1 0.2 0.6 1.3 1976 < 0.1 0.1. 1.0 1.8 1977 0.1 0.1 0.1 0.4 1.2 3.4 1978 < 0.1 0.1 1.4 5.3 1979 1980 0.2 0.7 i
O O LO TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES FR.0M 1973-1980, FOR LAKE ANNA.
% Lower % Upper %
- WHTF Total Reservoir Total Reservoir Total Ictaluridae Ictalurus natalis 1973 3.8 4.4 1.5 2.0 4.4 4.4 m 1974 2.5 5.2 2.1 3.3 1.5 4.3 e 1975 2.5 6.2 0.4 0.9 1.5 3.4 2 1976 1.7 3.0 0.2 0.3 1.2 2.2 1977 0.6 1.6 0.7 2.0 1978 < 0.1 0.1 0.3 1.3 1979 < 0.1 0.4 0.4 1.4 1980 0.2 0.8 0.3 1.0
- 1. nebulosus 1973 12.9 15.1 16.5 22.6 30.1 30.1 1974 14.2 29.6 16.3 25.5 22.8 52.0 1975 8.2 20.5 14.7 34.3 12.2 27.8 1976 10.9 20.0 11.2 26.6 15.8 30.6 1977 3.2 8.5 1.8 7.0 4.6 13.4 1978 1.6 7.5 2.4 7.1 2.1 8.1 1979 0.3 1.6 1.0 4.7 0.9 3.1 1980 0.5 2.0 0.5 1.4 0.4 1.3 e
e
O - O O TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSE0 IN NUPEERS OF INDIVIDUALS 8Y SPECIES FROM 1973-1980, FOR LAKE ANNA. 1
% Lower % Upper %
! WHTF Total Reservoir Total Reservoir Total I. punctatus 1973 0.1 0.1 1974 0.2 0.4 0.3 0.4 0.5 1.4 1975 0.4 1.0 0.6 1.4 0.8 1.8 1976 0.1 0.2 0.4 1.0 0.9 1.6 7 1977 0.3 0.8 0.4 1.6 0.6 1.6 C 1978 1.2 5.4 1.3 3.9 0.4 1.6 1979 2.4 11.9 1.7 8.2 0.6 2.0 1980 1.3 5.0 1.8 4.9 1.3 4.3 Centrarchidae Lepomis auritus 1980 < 0.1 < 0.1 L_. gibbosus 1973 0.7 0.8 0.2 0.2 0.3 0.3 1974 0.1 0.1 0.1 0.2 1975 0.1 0.2 < 0.1 < 0.1 0.2 0.4 1976 < 0.1 0.1 0.3 0.4 1977 < 0.1 0.1 < 0.1 0.2 < 0.1 0.1 1978
< 0.1 0.3 1979 < 0.1 0.4 0.2 0.8 < 0.1 0.3 1980 < 0.1 < 0.1 0.3 1.0 ~ .* ,- - ,
s i O . O O TABLE 6.3.2.1 (CONTINUED) CATCif PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES 4 FROM 1973-1980, FOR LAKE ANNA.
%. Lower % Upper %
WHTF Total Reservoir Total Reservoir Total l_. quiosus 1973 0.1 0.1 0.1 0.1 1974 0.4 0.8 1975 < 0.1 < 0.1 0.2 0.4 1976 0.1 0.1 T 1977 0,1 0.4 Z 1978 < 0.1 0.1 0.2 0.6 1979 0.1 0.6 < 0.1 0.3 1980 0.1 0.3 0.1 0.3 L. macrochirus 1973 0.9 1.0 0.7 0.9 0.7 0.7 1974 0.4 0.8 1.5 2.3 0.1 0.2 1975 0.3 0.7 1.3 3.0 0.6 1.3 1976 '0.7 1.2 0.5 1.0 0.5 0.9 1977 0.3 0.6 0.3 1.2 0.4 1.2 1978 0.5 - 2.1 0.4 1.2 0.4 1.6 1979 0.3 1.8 1.0 4.5 0.7 2.3 1980 0. 'e 1.5 0.3 0.8 1.0 3.3 4 e
O O O-TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES FROM 1973-1980, FOR LAKE ANNA.
% Lover % Upper %
WHTF Total Reservoir Total. Reservoir Total L. microlophus 1973 1974 0.1 0.2 < 0.1 < 0.1 1975 <0I < 0.1 0.4 0.9 0.1 0.2 m 1976 < 0.1 0.1 < 0.1 0.1 < 0.1 < 0.1
, '. 1977 0.1 0.2 < 0.1 0.1 on 1978 0.2 0.7 1979 < 0.1 0.2 1980 0.1 0.4 Micropterus salnoides 1973 6.9 8.1 6.6 9.0 1.5 1.5 1974 3.4 7.0 1.9 2.9 0.4 1.1 1975 3.1 7.7 1.9 4.4 1.0 2.2 1976 4.1 7.6 1.1 26.0 0.8 1.5 1977 1.7 4.5 1.1 4.4 0.8 2.1 1978 4.9 23.3 1.2 3.7 0.6 2.2 1979 3.4 16.8 1.9 4.5 0.6 2.0 i
!)80 1.3 5.0 0.9 2.5 0.3 1.0 d
O O O 4 1 TABLE 6.3.2.1 (CONTINUED) CATCH PdR DAY AS EXPRESSED IN NtESERS OF INDIVIDUALS BY SPECIES FROM 1973-1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total Pomoxis nigromaculatus 1973 0.7 0.8 2.8 3.8 4.5 4.5 1974 1.5 3.1 2.7 4.2 1.8 5.1 1975 2.0 5.0 3.1 7.2 4.4 10.0 m 1976 1.3 2.3 1.5 3.5 6.1 11.7
, L 1977 0.7 1.8 2.0 7.8 3.2 9.2
- 1978 2.2 10.2 2.5 7.2 11.3 42.5 1979 1.8 8.7 1.3 5.9 8.9 30.4 1980 0.7 2.8 1.1 3.0 8.5 28.0 Percidae Perca flavescens 1973 0.1 0.1 0.3 0.4 0.4 0.4 1974 0.1 0.2 0.5 0.7 0.2 0.5 1975 0.5 1.2 1.0 2.3 0.1 0.2 1976 0.6 1.1 0.7 1.7 0.6 1.8 1977 0.4 1.0 2.0 8.0 0.3 0.9 1978 0.5 2.5 1.5 4.5 0.3 1.3 1979 0.2 0.8 1.3 5.9 0.4 1.6 1980 0.1 0.4 0.6 1.6 0.3
O O O TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES FROM 1973-1980 FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total Stizostedium vitre_um 1973 1974 1975 m 1976 0 1977 0.3 0.8 1.1 4.4 0.3 0.9
" 1978 0.1 0.5 0.3 1.0 1979 0.2 0.8 1980 Percichthyidae Morone americana 1973 1974 1975
< 1976 < 0.1 0.1 1977 0.3 1.2 < 0.1 0.1 1978 1.8 8.4 3.5 10.4 1.8 6.6 1979 4.1 20.1 6.6 30.9 10.6 36.1 1980 6.3 24.3 10.3 28.2 8.6 28.2
O O O TABLE 6.3.2.1 (CONTINUED) CATCH PER DAY AS EXPRESSED IN NUMBERS OF INDIVIDUALS BY SPECIES FROM 1973-1980 FOR, LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total M. saxatilis 1973 1974 cn 1975 < 0.1 < 0.1
, '. 1976 0.1 0.1 0.3 0.7 oo 197' O.1 0.3 0.1 0.3 1978 0.1 0.5 0.5 1.6 1979 0.7 3.3 0.3 1.8 1980 0.9 2.5 i
4 1 1 e e - _ _ _ _ _ _ _ _ _ _ _ _
O O O F TABLE 6.3.2.2 CATCH PER NET DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY SPECIES FOR 1975-1980 FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total Anguillidae Anguilla rostrata 1977 < 0.1 Clupeidae [ Dorosoma cepedianum e 1975 1.6 10.8 2.3 18.5 2.3 19.3 1976 3.8 23.8 2.3 18.4 2.8 16.5 1977 1.8 22.2 1.1 16.1 1.2 10.1 1978 0.5 5.6 1.3 15.1 0.5 8.9 1979 0.5 6.3 0.4 6.4 0.4 5.6 1980 1.3 28.9 1.4 18.7 0.5 7.6 Esocidae Esox niger 1975 1.6 10.8 0.9 7. 4, 0.9 7.7 1976 1.3 8.1 1.4 1.1 1.0 6.1 1977 0.8 9.9 0.1 1.3 0.9 1.7 1978 0.1 1.1 1979 0.1 0.7 0.3 4.0 0.2 2.2 1980 < 0.1 0.6 0.4 5.4
O O O TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY SPECIES FOR 1975-1980 FOR LAKE ANNA.
% Lower % Upper %
i WHTF Total Reservoir - Total Reservoir Total Cyprinidae Cyprinus carpio i 1975 3.4 23.0 2.9 23.3 3.0 25.2
. 1976 1.3 8.0 3.1 24.8 3.9 23.0 .
i 1977 1.8 22.4 1.9 28.1 3.5 30.5
$ 1978 4.2 45.8 2.1 24.4 1.4 26.3 1979 3.0 36.2 2.3 35.7 4.1 60.0 1980 0.7 15.6 1.8 24.1 1.1 16.7 Notemigonus crysoleucas 1975 < 0.1 0.1 0.1 0.1 0.1 0.1 1976 0.1 0.4 0.1 0.1 0.1 0.2 1977 < 0.1 0.5 0.1 0.2 0.2 1.4 1978 0.1 0.1 0.1 0.3 1979 1980 < 0.1 0.1 e
O O O TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY SPECIES FOR 1975-1980,FOR LAKE ANNA
% Lower % Lower %
WHTF Total Reservoir Total Reservoir Total Catastomidae Catostomus commersoni 1975 0.1 0.4 0.6 4.7 e 1976 < 0.1 0.2 0.1 0.2 0.7 4.1
% 1977 0.1 0.8 0.5 3.9 1978 0.1 1.7 1979
~
1980 0.9 13.6 Erimyzon oblongus 1975 4.1 27.8 2.4 19.3 2.0 16.8 1976 3.9 24.3 2.3 18.1 2.5 15.0 1977 1.0 12.7 0.7 11.1 1.3 11.6 1978 0.1 0.8 0.2 1.4 1979 < 0.1 0.5 0.1 0.1
- 1980 0.1 1.3 -
Moxostoma macrolepidotum 1980 0.3 4.5
O O O TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EX?RESSED BY WEIGHT (kg) 0F INDIVIOUALS BY SPECIES FOR 1975-1980, FOR-LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total l Ictaluridae Ictalurus natalis
. 1975 0.7 4.8 0.1 0.9 0.2 1.3 i 1976 0.7 4.3 0.1 0.5 0.4 2.6
% 1977 0.2 2.4 0.2 1.6 1978 0.1 0.1 0.1. 1.1 1979 0.1 0.1 0.2 2.2 1980 < 0.1 0.6 < 0.1 0.5 I. nebulosus 1975 0.9 6.2 1.4 11.3 1.2 10.1 1976 1.0 6.5 1.3 10.2 1.5 8.9 1977 0.4 4.4 0.2 3.2 0.5 4.6 1978 0. l' l.4 0.5 5.9 0.4 6.8 1979 < 0.1 0.4 0.1 1.7 0.5 7.5 1980 0.1 2.2 0.1 1.3 0.1 1.5
~ O O O TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY SPECIES FOR 1975-1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total I_. punctatus 1975 0.3 2.2 0.3 2.7 0.9 7.8 4 1976 0.2 1.0 0.4 2.8 1.4 8.5 1977 0.5 6.4 0.6 8.4 0.9 7.8 m 1978 1.7 18.3 2.0 23.2 0.4 8.7 8 1979 0.5 5.5 1.4 21.6 0.6 9.1 U 1980 1.1 24.5 1.5 20.1 2.3 34.9 Centrarchidae Lepomis auritus 1980 < 0.1 < 0.1 i Lepomis gibbosus 1975 < 0.1 4.1 < 0.1 < 0.1 < 0.1 0.1 1976 < 0.1 < 0.1 0.1 0.4 1977 < 0.1 0.1 < 0.1 0.2 < 0.1 0.1 1978 < 0.1 0.1 1979 < 0.1 0.1 < 0.1 0.3 < 0.1 < 0.1 1980 < 0.1 0.2
O O O TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGilT (kg) 0F INDIVIDUALS BY. , SPECIES FOR 1975-1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir Total L. gulosus 1975 < 0.1 < 0.1 < 0.1 0.1 1976 < 0.1 < 0.1 1977 < 0.1 0.2 1978 < 0.1 0.1 < 0.1 0.5 m 1979 < 0.1 0.1 < 0.1 < 0.1 b
+
1980 < 0.1 0.2 < 0.1 < 0.1 L. macrochirus 1975 < 0.1 0.1 0.2 1.5 < 0.1 0.2 1976 < 0.1 0.3 < 0.1 0.2 < 0.1 0.1 1977 < 0.1 0.3 < 0.1 0.3 0.1 0.4 1978 < 0.1 0.3 < 0.1 0.3 < 0.1 0.3 1979 < 0.1 0.2 0.1 1.0 < 0.1 0.2 1980 < 0.1 0.2 < 0.1 0.3 < 0.1 0.6 L_. microlophus 1975 < 0.1 < 0.1 < 0.1 0.2 < 0.1 < 0.1 1976 < 0.1 0.1 < 0.1 0.1 < 0.1 < 0.1 1977 < 0.1 0.2 < 0.1 < 0.1 1978 < 0.1 0.2 1979 < 0.1 0.2 1980 < 0.1 0.3 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ m
O s O O-l TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY SPECIES FOR 1975-1980, FOR LAKE ANNA.
% Lower % Upper %
WHTF Total Reservoir Total Reservoir ' Total Micropterus salmoides 1975 1.8 12.2 1.3 10.5 0.4 3.7 1976 3.4 21.4 0.9 7.4 1.1 6.3 1977 0.9 11.2 0.8 12.0 0.5 4.7 m 1978 1.0 11.3 0.8 9.3 0.2 4.2 L 1979 1.3 16.0 0.6 9.5 0.1 1.5 1980 0.7 15.6 0.6 8.0 0.2 3.0 Pomoxis nigromaculatis 1975 0.2 1.6 0.3 2.6 0.2 2.0 1976 0.2 1.3 0.2 1.5 0.4 2.4 1977 0.1 1.5 0.2 3.2 0.2 1.8 1978 1.0 10.4 0.2 2.4 0.6 11.0 1979 0.1 0.6 0.1 1.3 0.4 5.8 1980 0.1 2.2 0.1 1.3 0.4 6.1 i
- - - - - _ _ _ . _ -._m__.____
O O O l TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY t SPECIES FOR 1975-1980, FOR LAKE ANNA. I % Lower % Upper % WHTF Total Reservoir Total Reservoir Total Percidae Perca flavescens 1975 0.1 0.3 0.2 1.2 < 0.1 < 0.1
? 1976 < 0.1 0.2 0.1 0.7 0.1 0.8 y 1977 0.1 0.9 0.1 0.9 0.1 0.4
, 1978 < 0.1 0.3 0.1 1.4 < 0.1 0.2 1979 '< 0.1 < 0.1 0.1 1.1 < 0.1 0.1 1980 < 0.1 0.3 < 0.1 0.4 < 0.1 0.2 i Stizostedium vitreum 1975 , . 1976 l 1977 0.2 2.0 0.8 12.2 0.2 2.1 1978 0.1 1.3 0.4 4.5
- 1979 0.2 2.4 1980 l
1 0 0 3 . v-- - y - . _ _ . _ , _ -
o l O o~ I i. i t i TABLE 6.3.2.2 (CONTINUED) CATCH PER DAY AS EXPRESSED BY WEIGHT (kg) 0F INDIVIDUALS BY SPECIES FOR 1975-10d0, FOR LAKE ANNA. ! % Lower % Upper % WHTF Total Reservoir Total Reservoir Total i l J i Percichthyidae i, Morone americana
?
N 1975
< 0.1 0.1 l 1976 1977 0.1 0.9 < 0.1 0.1 0.2 1.8 0.3 2.9 0.1 2.1
' 1978 0.2 2.6 0.5 7.4 0.6 8.2 1979 l 1980 0.4 8.9 0.6 8.0 0.7 10.6 H. saxatilis 1975 1976 < 0.1 0.3 0.3 2.2
< 0.1 0.1 0.1 0.6 1977 i 1978 0.3 3.7 0.6 7.5 1979 2.6 30.8 0.3 4.4 0.8 10.7 1980
The distribution of the gizzard shad in Lake Anna appears to show no clear trend with the exception of a gradual decline in numbers and kg/ net day noted from 1978-1979, but has in-creased in gill net catches during 1980 (Tables 6.3.2.1 and 6.3.2.2). The chain fickerel, Esoy niger, has suffered a general decline in numbers and biomass gill net catches throughout the study (Tables 6.3.2.1'and 6.3.2.2). This decline can be re-lated to the fact that aquatic vegetation along the shore and in low areas is restricted and this species depends on aquatic vegetation and low lying swampy areas for reproduction (Mansueti and Hardy, 1967). The' carp, Cyprinus carpio, has displayed an overall uni-form increase in percentage of total catch per net day as well as kg per net day (Tables 6.3.2.1 and 6.3.2.2) in the WHTF as well as the Reservoir stations. This species typically has comprised from 23% to as much as 60% of the total biomass of fish caught per net day (Table 6.3.2.2). In 1980 a decline in relative abundance was noted for this species. () Erimyzon oblongus, the creekchub sucker. has shown a natural decrease in numbers and biomass over the years as the reservoir aged (Table 6.3.2.1). This species is typically associated with rivers and streams and was expected to display a decline in population. The shorthead redhorse, Moxostoma macrolepidotum, however, increased in numbers and biomass in the Upper Reservoir during 1979 (Tables 6.3.2.1 and 6.2.2.2) and a slight decline was observed during 1980. Ictalurus natalis and I. nebulosus, of the family Icta-luridae, displayed a decrease in catch per unit effort thrcugh-out the study (Table 6.3.2.1). The channei catfish, I. punctatus, however, has shown a marked increase in catch per unit, effort and kg/ net day. It has been demonstrated that channel catfish have unusually good reproduction in a reservoir receiving heat-ed effluent due to the increased temperature and artificial l l current produced in the cooling lake (Larimore and Tranquilli, ! 1977). Gummon (1973) reported that flathead catfish and perhaps ! channel catfish increased reproduction and density in thermally affected areas of the Wabash River and it appears that, at this point, channel catfish have increased in number and biomass in l Lake Anna. The sunfish family, Centrarchidae, generally was not caught in great numbers with gill nets because tney typically occupy littoral areas that were inaccessible to gill netting. The 6-28
\j largemouth bass, Micropterus salmoides, and the black crappie Pomoxis nigromaculatus, however were well represented in the gill net catches (Table 6.3.2.1). Three times as many bass were reported taken in a hotwater arm than in a control arm in a heated effluent study (Witt, Campbell and Whitley,1970) and Lake Anna appeared to be following a similar pattern, but in 1980 a decrease in number of bass caught per net day occurred. However, kg/ net day of bass captured remained high (Table 6.3.2.2). Neill and Magnuson (1972) reported that blue-gill, pumpkinseed and largemouth bass were significantly higher in terms of catch per unit effort (c/g) in heated areas.
The largemouth bass displayed a marked increase in numbers in the WHTF in 1979, but they fell in catch per net day during However, bass were caught more frequently in the WHTF 1980. during 1980 when compared to other Lake Anna stations. The black crappie, Pomoxis nigromaculatus, displayed a slight decrease in c/f, while kg/ net day increased in the WHTF and Upper Reservoir stations (Tables 6.3.2.1 and 6.3.2.2). Black crappie have been shown to avoid areas affected by heated effluent (Ruelle, Lorenze.n and Oliver, 1977), but no clear trend for this species can be determined at this point in time for (]) Lake Anna. The yellow perch,Perca flavescens, generally displayed erratic results and, therefore, no trend can be established. The white perch, Morone americana, demonstrated a marked increase in catch per net day in all study areas of Lake Anna but kg/ net day declined in the Upper and Lower Reservoir (Table 6.3.2.2.). The striped bass, M. saxatilis, showed an in c/f in the Lower Reservoir, perhaps due to attraction of the artifical current. However, during 1980 no striped bass were caught in the WHTF. In terms of total catch per day the WHTF displayed the lowest value during 1979 and 1980 for numbers of individuals caught per net day, and the k/g net day was lower in the WHTF than the other two areas (Tables 6.3.2.3 and 6.3.2.4). In general the WHTF has shown an overall decrease in catch per net day which remains less than the other two sampling areas. 6.3.3 Cove Rotenone Studies Results from cove rotenone samples are given in Table 6.3.3.1. Included in this table are the mean standing crop estimates by species and area for the year 1975 through 1980. A total of 26 coves were sampled throughout this period and all values have been converted to kg/ hectare for purposes of comparison.
)
6-29 i _ . _ . ~
O R O F S L A U D I V I r D i N ro 0 3 8 3 4 7 8 0 I ev pr 0 9 8 4 4 6 2 4 F pe 0 4 3 1 4 6 9 0 O Us 0 3 4 5 3 2 2 3 e 1 S R e R E B M U N S A n r D o i E S i ro g ev 6 8 2 2 3 0 5 5 0 7 8 9 7 9 2 5 S e wr E R oe 2 3 2 1 4 3 1 6 R Ls 7 6 4 4 2 3 2 3 O P X E R e Y A ._ D . 0 _ T8 _ E9 N1
- F 9 0 0 4 8 0 4 0 R3 T 0 9 0 2 3 0 3 9 E7 H P9 W 5 7 0 4 7 1 0 5 1 8 4 4 5 3 2 2 2 H .
. C , TA - AN
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- L AE TK OA TL r 3 4 5 6 7 8 9 0 3 . a 7 7 7 7 7 7 7 8 e 9 9 9 9 9 9 9 9 2 Y 1 1 1 1 1 1 1 1 3 6 E . L B A T O
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TABLE 6.3.2.4 TOTAL CATCil PER AET DAY IESSED AS WEIGHT (kg) FOR O 4 LAKE ANNA, 1975-1980. Region f ! Lower Upper Year WHTF Reservoir Reservoir 1975 14.75 14.72 11.90 1 1976 15.90 12.50 16.90 T 1977 7.% 6.57 11.43 4 w i ~ 1978 9.16 8.50 5.12 1979 8.35 6.33 6.73
- 1980 4.49 7.47 6.60 iI h
i 4 i I I
=,~~w- - , - , _ .
--,,7_n.,, _. , _ , , , _ , __ _ _ _ ,
O O O TABLE 6.3.3.1 FISH STANDING CR0P ESTIMATES BASED UPON COVE ROTEN0NE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/ hectare), 1975 - 1980 WHTF , Lower Reservoir Upper Reservoir Moody Millpond Dam Mid NAR Pamunkey Creek Creek Cove Lake Arm Creek Mean Anguillidae Anguilla rostrata 1975 0.90 0.45 m 1976 0.19 2.06 0.37 *0.25 0.52 03 1977 0.75 0.23 62 1978 0.20 0.68 0.15 1979 0.01 1.18 0.19 1980 1.02 0.17 Clupeidae Dorosoma cepedianum 1975 190.90 146.10- 168.50 1976 144.48 56.60 40.54 138.54 *153.83 114.64 1977 52.93 78.32 134.71 103.24 159.56 182.87 118.60 1978 39.63 144.57 44.16 80.21 247.95 71.00 104.59 1979 42.64 41.96 55.25 86.82 137.06 157.32 86.84 1980 38.03 65.99 35.56 123.00 219.76 236.35 119.78
h v
\
(>N TABLE 6.3.3.1 (Continued) FISH STANDING CROP ESTIMATF BASED UPON COVE ROTENONE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/hectars). 1975 - 1980 WHTF Lower Reservoir Upper Reservoir Moody Millpond Dam Mid NAR Pamunkey Creek Creek Cove Lake Arm Creek Mean Esocidae Esox niger 1975 2.90 2.30 2.60 1.17 2.90 0.10 1.82 *l.69 1.54 7 1976 1.71 0.22 0.23 1.04 0.67 0.64 u> 1977 1978 0.94 7.59 2.04 0.05 0.08 1.79 1979 1.75 1.86 0.41 3.47 2.01 0.54 1.67 1980 1.02 15.84 0.87 0.73 2.23 0.61 3.55 E. lucius 1976 2.72 0.90 Cyprinidae Cyprinus carpio 1975 1.70 0.85 1976 37.64 13.45 3.67 *7.84 12.52 13.26 94.42 17.94 1977 29.27 1978 35.43 13.83 24.97 13.52 87.85 19.41 4.32 27.67 22.13 12.25 1979 20.77 1980 9.27 63.45 47.15 4.76
O O O TABLE 6.3.3.1 (Continued) FISH STANDING CROP ESTIMATES BASED UPON COVE ROTEN0NE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/ hectare), 1975 - 1980 WHTF Lower Reservoir Upper Reservoir Moody Millpond Dam Mid NAR Pamunkey Creek Creek Cove Lake Arm Creek Mean Notemigonus crysoleucas 1975 0.50 0.25 1976 2.92 2.45 0.39 *1.60 1.49 1977 1.21 1.23 1.21 0.46 0.96 0.85 o' 1978 1.28 2.25 0.77 1.41 1.86 0.54 0.35 d> 1979 2.73 0.69 0.30 1.58 0.48 1.05 1.13
*" 1980 0.26 < 0.01 0.62 0.17 0.18 Notropis analostanus 1977 0.03 0.12 0.02 1978 0.01 0.12 0.05 1979 1980 -
4 0.01 N. procne 1977 0.02 0.05 0.01 1978 0.01 0.01 0.01 1979 0.01 0.01
' " " - V Ww -7v-w- -- m, ,,_.y m_ , , . _ , , , _ . _ , , ,,
O O O TA8LE 6.3.3.1 (Continued) FISH STANDING CR0P ESTIMATES BASED UPON COVE ROTEN0NE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/ hectare), 1975 - 1980 3 WHTF Lower Reservoir Upper Reservoir ! Moody Millpond Dam Mid NAR Pamunkey j Creek Creek "ove Lake Arm Creek Mean i Catostomus commersoni 1977 8.55 1.43 1978 2.53 19.04 3.60 1979 2.00 0.33 i' 1980 4.42 2.15 1.10
$ Erimyzon oblongus 1975 23.90 17.10 20.50 1976 3.07 0.32 3.35 12.37 *9.18 5.66 1977 1.15 1.43 0.74 1.08 0.02 3.10 1.25 1978 0.37 1.12 3. 2.1 0.93 0.39 1.33 1.23 j 1979 0.06 0. f2 0.80 2.90 0.64
. 1980 1.20 2.69 0.75 0.62 0.88 Moxostoma macrolepidotum 1975 4.10 2.05 1976 1977 1.68 8.69 1.73 1978 4.51 0.75 1979 2.18 3.30 0.91 1980 4.53 0.76
+-n. ,s - - y _ w
O O O TABLE 6.3.3.1 (Continued) FISH STANDING CR0P ESTIMATES BASE 0 UPON COVE ROTENONE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/ hectare), 1975 - 1980 > WHTF Lower Reservoir Upper Reservoir Muody Millpond Dam Mid NAR Pamunkey Creek Creek Cove Lake Arm Creek Mean Aphredoderidae Aphredoderus sayanus , 1975 0.01 0.01 0.01 0.01 m 1976 L, 1977 0.01 m Ictaluridae Ictalurus natalis 1975 0.80 1.30 1.05 1976 6.57 2.65 1.87 4.33 *4.33 3.96 1977 7.36 2.08 0.77 0.45 0.25 1.58 2.08 1978 3.93 1.77 0.39 0.54 1.56 0.95 1.52 1979 2.42 2.11 0.31 0.30 1.62 2.17 1.48 1980 1.47 4.60 1.62 2.02 1.50 1.87 I. nebulosus 1975 6.40 0.60 3.50 1976 35.02 0.41 17.45 0.53 *6.09 11.90 1977 0.10 0.60 0.41 0.90 1.71 5.90 1.60 1978 0.91 1.87 0.07 11.60 0.60 4.25 3.22 1979 3.86 14.94 0.66 4.13 0.22 2.40 4.37 1980 1.55 0.41 7.73 1.70 0.22 0.60 2.04
O O O TABLE 6.3.3.1 (Continued) FISH STANDING CR0P ESTIMATES BASED UPON COVE ROTENONE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/ hectare), 1975 - 1980 WHTF Lower Reservoir Upper Reservoir Moody Millpond Dam Mid NAR Pamunkey Creek Creek Cove Lake Arm Creek Mean
. I. punctatus 1975 2.60 0.80 1.70 1976 2.09 6.57 7.63 *l.01 3.46 1977 0.57 10.83 1.73 10.25 3.89 7' 1978 0.03 0.02 9.55 2.76 1.06 2.24 w 1979 3.90 0.76 0.80 10.61 2.28 12.48 5.13 1980 14.70 22.23 0.48 3.68 6.74 Noturus insignis 1976 0.01 0.01 1977 1978 1979 0.01 0.01 Enneacanthus gloriosus 1976 0.01 0.01
. 1977 0.01 0.01 0.01 1978 1979 0.02 0.01
O S E n 421847 587123 555579 L a 352304 622579 787331 P e . . . . .. . . . . . . . . . . . . M M 001011 515974 008414 A 11 369667 S E N r y 0 i e N o kk 8404 1216 8944 E v ne 4993 1040 0459 T r ue . . .. . . . . . . . . O R e mr 0000 7095 6539 s aC 2211 9337 e P 1111 E R V0 O8 r C9 e 059607 077025 094812 1 p Rm 676792 387829 473676 N p Ar . . . . .. . . . . . . . . . . . . O - U NA 001001 651210 396807 P
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O O O TABLE 6.3.3.1 (Continued) FISH STANDING CR0P ESTIMATES BASED UPON COVE ROTEN0NE SAMPLES BY SPECIES FROM LAKE ANNA (mean kg/ hectare), 1975 -1980 WHTF ' Lower Reservoir Upper Reservoir Moody Millpond Dam Mid NAR Pamunkey Creek Creek Cove Lake Arm Creek Mean i Percichthyidae Morone americana 1976 0.47 *0.02 0.09 m 1977 0.01 0.03- 0.46 0.17 1.54 0.37 E 1978 0.01 0.02 3.05 0.48 4.17 1.29 1979 0.75 0.01 7.73 0.79 7.10 2.73 1980 1.19 1.11 0.57 13.28 5.11 3.80 4.18 M. saxatilis_ 1978 0.03 0.01 1979 0.08 0.01 0.01 1980 0.04 40.01 Total Species 1975 279.97 227.60 253.90 1976 373.41 124.35 220.80 313.61 *353.36 277.10 1977 272.87 271.60 191.90 269.58 279.05 587.63 311.91 1978 164.84 275.84 93.41 199.74 376.19 380.25 248.43 1979 219.89 166.70 81.73 210.65 227.36 412.72 219.41 1980 117.35 196.64 200.21 261.81 334.35 487.96 266.39
- Mean for two coves sampled on the North Anna River arm during 1976.
, ~w-r-, -w- y _
O Clupeids were the most frequently impinged fish at southern power plants and made up 40-55% of the biomass in cove rotenone samples (Jenkins, 1977). If power plant in-duced mortalities have in fact affected fish populations in the receiving water, it should be first detected by changes . in the Clupeid standing crop (Jenkins, 1977). In a heated effluent study.in South Carolina it was reported that the threadfin shao, Dorosoma oetenense, population remained remained constant (Ruelle, Lorenzen and Oliver,1977), where-as in Lake.Sangchris, Illinois the gizzard shad population standing crop appears to be relatively constant.
.The gizzard shad in Lake Anna comprised from 38-66% of the total mean standing crop and was found to be the most ,
important fish in the lake in terms of standing crop. The Upper Reservoir generally displayed higher gizzard shad standing crop values with the WHTF and Dam Cove showing the lowest standing crop values for this species. Decreases in the standing crop of shad were observed at the Moody Creek and Dam Cove stations for 1980 (Table 6.3.3.1), but the mean standing crop overall was 40% greater in 1980 than 1979. O The family Esocidae, represented by the single species Esox niger has demonstrated a marked increase in standing , crop from 1978-1980 (Tabl e 6. 3.3.1) . The carp, Cyprinus carpio, increased in biomass through-out the study from 4.2% up to 11.77% of the total standing crop of fish taken from Lake Anna. In similar studies the carp accounted for 34-46% of the standing crop of fish (Goldstein, 1976; Witt, Campbell and Whitley, 1970) The population of carp in Lake Anna has not reached these propor-tions, but it has been reported the spawning of carp in Lake Sangchris was initiated two weeks earlier in heated areas than in ambient areas (Larimore,1975) which could produce a positive effect on the standing crop of this species in the WHTF in the future. In addition, carp appear to exhibit a distinct preference for the warmest zones (Gammon,1973; Neil ! and Magnuson, 1972) and have been found in summer temperatures ' exceeding 33*C in an effluent canal discharging into the White
- River, Indiana (Proffitt, 1969). In one study, however, carp
! were picked up less in heated areas than In in control Lake Anna, areas the during (Witt, Campbell and Whitley, 1970). 1980 rotenone study no carp were collected in the WHTF at the Moody Creek station, but an increase in carp standing crop was noted at the WHTF M111 pond Creek site (Table 6.3.3.1). O~ 6-42 l I
V The sucker family, Catostomidae, was well represented in the Upper Reservoir with higher standing crop values and more sucker species than other locations sampled (Table 6.3.3.1). Even though Erimyzon oblongus was collected at more stations than other suckers, this species remains on a steady decline. This is not unusual since this fish is typically a river form and would be expected to decline in a lentic situation due to the lack of proper habitat. It has been documented that the family Ictaluridae (cat-fishes) are highly tolerant of heated discharges associated with power plant operations (Dryer and Benson, 1957; Marcy, 1976; Gammon, 1973) and channel catfish have shown exceptional reproduction in a power plant study at Lake Sangchris, Illinois - (Larimore and Tranquilli, 1977). Brown bu11 heads in the Connecticut River moved into the heated effluent discharge canal of the Connecticut Yankee Atomic Power Company's Haddam Neck Plant in large numbers and comprised 67% of the total catch and 68% of the total catch in the winter (Marcy, 1976). The optimum temperatures for channel catfish, Ictalurus punctatus, in the Wabash River were reported to lie in the range between 30-32*C (Gammon, 1973) and the temperature tol-O erance for brown bullheads was reported to be 33*C, in addition, this species will enter 40*C water for food (Marcy, 1976). The three species of catfish in Lake Anna, which include the yellow I. nebulosus bullhead,Ictalurus natalis, I. and the channel catfish, thepunctatus, brown bullhead, Tayed a marked have disp increase in standing crop in the WHTF during the first opera-tional years of 1978-1979 (Table 6.3.3.1), but during 1980 no channel catfish were collected in rotenone sampling in the WHTF but the standing crop increased in the Upper and Lower Reservoir. i Yellow bullheads exhibited an increase in standing crop in 1980, while brown bu11 heads decreased. i l The sunfishes (Centrarchidae) in general have displayed ! higher densities or catch rates in areas affected by heated effluents from power plants than in control areas (Witt, Campbell and Whitley,1970; Neill and Magnuson,1972). Black crappie young of the year have been shown to be inversely re-lated to power plant generation, especially in the hot water areas whereas other sunfish young of the year were uniformly distributed between hot and cold water stations (Ruelle, l Lorenzen and Oliver, 1977). Although sunfish appear to tol-erate and even be attracted to areas affected by heated effluent, elevated temperatures have been shown to adversely affect bluegill eggs (Banner and Van Arman,1973) which could affect the standing crop of this species in the WHTF in subsequent years. 6-43
)
The pumpkinseed, Lepomis gibbosus, had been cited as one of the more tolerent of the sunfish species to thermal effluent and has been collected in water up to 40*C (Marcy, 1976). In Lake Anna, howe.er, the pumpkinseed appears to inhabit the two upper arms of the reservoir more extensively than the WHTF as indicated by the standing crop values throughout the study period (Table 6.3.3.1). Bluegills comprised from 12% up to 31.6% of the standing crop in Lake Anna from 1975-1980 with a mean of 23.88%. In a similar rotenone study performed on a lake receiving heated effluent bluegills only comprised 8.6% of the total standing crop (Witt, Campbell and Whitley, 1970). The Upper Reservoir contains the highest standing cro, of bluegills with Pamunkey Creek consistantly higher than all other stations. - Yellow perch, perca flavescens, generally have displayed less abundance in thermally affected areas than do most other 1 species found in southern reservoirs (Ruelle, Lorenzen and Oliver,1977) and also this species was shown to be less abun-dant in Lake Monona, Wisconsin near thermal outfall areas (Neill and Magnuson, 1972). In Lake Anna the yellow perch had displayed a high standing crop value at the mid-reservoir h_s) station until 1980, when it declined greatly. A large increase in yellow perch standing crop was observed for the Dam Cove, the other stations showed mixed results, some declined, others increased (Table 6.3.3.1). In terms of total standing crop the Upper Reservoir stations were shown to be higher than the remainder of the stations which has historically been the case. 6.3.4 Gonosomatic Index of the Female, Micropterus salmoides The mean gonosomatic index (gonad weight / body weight) observed < throughout the 1980 spawning season for the female largemouth bass is shown in Table 6.3.4.1. Historically the female bass , have reached a peak of gonad development in the Reservoir and WHTF from mid to late April. During 1979, female bass at the Mid-RL.Jrvoir electrofishing station displayed a peak of gonad ! development in the third week of April, but female bass observed in the WHTF reached their peak gonad development during the last week of March. A similar phenomenon was observed for 1980 with rapid gonad development occurring in early April in bass in the WHTF, followed by similar development in mid and late April in , the Reservoir bass (Table 6.3.4.1). In addition female bass were observed " squeeze ripe" in the WHTF on April 10 whereas they were not observed in spawning condition (squeeze ripe) i v 6-44
i . (:) l ' TABLE 6.3.4.1 GONOS0MATIC INDEX (%) 0F THE FEMALE ' LARGEMOUTH BASS IN LAKE ANNA, 1980. I Date WHTF Reservoir 4 {, 3/28.80 1.9 --- 4/3/80 . 5.5 3.3 . 4/10/80 6.0 6.1 l 4/24/80 --- 7.2 , i 5/1/80 2.9 5.2
- 5/9/80 ---
3.4 I () 1 4 \ O 6-45 , i I
t t . O at the Mid-Lake station until April 24, 1980. This difference in spawning time between the Reservoir.and the WHTF appears to be due to the operation of the reactor unit. The WHTF re-mained ice free during the winter and warmed much faster than the Reservoir, which was ice covered during the winter. Appar-ently this was enough to affect a difference in spawning times between these two study areas. This observation has been noted in past thermal effluent studies (Witt, Campbell and Whit 1cy, 1970; Larimore, 1975; Bennett and Gibbons, 1975). 6.3.5 Age and Growth of the Largemouth Bass, Microoterus salmoides Age was calculated utilizing scale samplas, and in addition, length-weight regression equations were generated to determine the overall development of this important game , species. The relationship of length-weight was calculated for individuals to generate a curve for the purpose of obtaining weights where only lengths are known and also for interpretation of the exponential growth function. These regression curves were generated separately for the WHTF and Lower Reservoir areas. Resulting length-weight equations in logarithmic form are as (]) follows: Lower Reservoir log Wt = -6.122 +3.50 WHTF
-log Wt = log -5.73 + 3.34 log L It has been stated that the length-weight regression equation slope will usually be above 3.0 because most fish be-come " plumper" as they grow (Carlander,1977). The slopes calculated for 1980 have slopes well above the cube of the length. The mean slope for 116 largemouth bass populations was 3.08 (Carlander, 1977), therefore, in the 1980 Lake Anna bass population more weight was being put on with length than tee national average.
Cellulose acetate impressions of scale samples were made for 179 bass in 1980. These were aged and distances to annuli and interior scale radii were measured. Relation between scale radius and total body length was determined for bass from the WHTF and Lower Reservo;r. The resulting relationships were () 6-46 1 l
/~ \_]
Consequently a linear, but not directly(proportional. Frazier-type correction Ricker, 1968) was used and the fol-lowing equations were employed to back calculate growth: Lower Reservoir L' = -8.80 + ( s ) (L - (-8.80) WHTF 5' L' = -5.96 + ( s ) (L - (-5.96) Growth rates were calculated for all year class taken and are shown in Tables 6.3.5.1 and 6.3.5.2. Using the mean calculated lengths for each group ANOVA's were calculated to test for differences between locations means. Age group I showed no significant difference between locations. 6.3.6 Food Habits of the largemouth Bass, Micropterus salmoides A to?.al of 62 largemouth bass were examined for gut content during 1980 (Table 6.3.6.1). It was found that the gizzard shad constituted a majority of the forage base for the largemouth bass (~')
%s in Lake Anna during 1980. Centrarchids remain second in terms of frequency of occurrence, as has historically been the case.
The families Percichthyidae and Percidae played a relatively minor role in the forage base for the largemouth bass (Table 6.3.6.1). Throughout the study period from 1977-1980, it was evident that the family Clupeidae, represented by the single species, ' Dorosoma cepedianum, was the most frequently selected forage fish in the diet of the largemouth bass in Lake Anna (Table 6.3.6.1). This may be attributed to the fact that the gizzard shad was found to be the most abundant fish in Lake Anna and was perhaps encountered by the bass more frequently than other prey species. D. cepedianum has also been noted as a valuable forage species Tn some other reservoir systems (Baker andBy feed-Schmitz,1971; Miller,1960; Jester and Jensen,1972). ing on phytoplankton the gizzard shad has the advantage of shortening the food chain from the basic nutrients to the pre-dator game fish level (Sandoz, 1956). This results in the transformation of living microscopic matter into flesh in one trophic step, which places D. cepedianum in an important position in the food chain of predatory fishes (Schneider, 1969). Therefore, the abundance of gizzard shad in Lake Anna may play a key role in the maintenance of the largemouth Any reduction in the shad bass population in this reservoir. 6-47
O O O TABLE 6.3.5.1 BACK CALCULATED LENGTH ATTAINED BY EACH YEAR CLASS OF LARGEMOUTH BASS AT EACH ANNULUS FOR FISH COLLECTED FROM LAKE ANNA (LOWER RESERVOIR, 1980). Mean Calculated Length at Annulus Year 3 Class N I II III IV V VI VII 2 492.70 544.14 1974 1 145.51 3 274.10 338.39 389.83 441.27 145.51 128.59 64.29 51.54 51.44 51.43 51.44 1975 2 118.61 234.11 309.00 400.04 443.09 485.95 118.61 115.50 74.89 91.04 43.05 42.86 1976 10 132.85 252.02 346.46 408.89 469.09 132.85 119.17 94.44 62.34 60.20 I 1977 7 121.30 255.13 362.41 434.13 121.30 133.83 107.28 71.73 1978 40 110.63 234.28 320.12 110.63 123.65 85.84 1979 34 116.39 240.73 116.39 124.34 1980 4 195.06 195.06 G S
O O O I TABLE 6.3.5.1 (CONTINUED) BACK CALCULATED LENGTH ATTAINED BY EACH YEAR CLASS OF LARGEMOUTH BASS AT EACH ANNULUS FOR FISH COLLECTED FROM LAKE ANNA (LOWER RESERVOIR, 1980). Mean Calculated Length at Annulus . Year i Class N y gg ggg gy y yg ygy Mean Total Length 134.33 248.39 335.28 408.22 451.15 489.33 544.14 as Hean 134.33 124.18 85.35 69.19 51.56 47.15 51.44 g Increment 1 Number of specimens in each age group 2 T.L. in mm 3 Mean increment of year class
O- O O TABLE 6.3.5.2 BACK CALCULATED l.ENGTH ATTAINED BY EACH YEAR CLASS OF LARGEMOUTH BASS AT EACH ANNULUS,YOR FISH COLLECTED FROM LAKE ANNA (WHTF, 1980). Mean Calculated Len9th at Annulus Year I Class N y ;g ygg gy y y; 1975 ? 128.65 2I 297.35 390.93 433.98 480.56 518.83 128.65 168.70 93.58 43.05 46.58 33.27 f; 1976 2 72.76 157.45 250.95 328.80 372.57 72.76 84.69 93.50 77.85 43.77 1977 19 139.96 243.93 323.30 393.97 139.96 103.97 79.37 70.67 1978 22 125.42 258.28 349.04 125.42 132.86 90.76 1979 16 122.15 249.63 122.15 127.48 ' 1980 20 173.71 173.71
O O O TABLE 6.3.5.2 (CONTINUED) BACK CALCULATED LENGTH ATTAINED BY EACH YEAR CLASS OF LARGEMOUTH BASS AT EACH ANNULUS FOR FISH COLLECTED FROM LAKE ANNA (WHTF, 1980). Mean Calculated Length at Annulus Year i Class N I. II III IV V VI Mean Total m Length 127.11 241.33 328.55 385.59 426.56 513.83 i Mean Increment 127.11 123.54 89.30 63.85 45.18 33.27 I Number of specimens in each age group 2 T.L. in mm 3 Mean increment for year class I
O . O O TABLE 6.3.6.1 GUT CONTENT OF THE L'ARGEMOUTH BASS. Micropterus salmoides, IN LAKE ANNA, 1980. (THE PRESENCE OF FISH FAMILIES FOUND IN THE GUT CONTENT IS EXPRESSED fo PERCENT OCCURRENCE). Month Clupeidae Centrarchidae Percidae Percichthyidae Empty Unidentified , M a .'c h 25.00 25.00 25.00 25.00 April 28.00 12.00 8.00 40.00 12.00 g May 17.24 3.40 3.40 62.00 6.89 Total 22.58 12.90 6.45 1.60 48.39 8.06 1 i w-e -
---w.-.y,qw--%9 .., %. _ , _ ., , _ , _ _ ,
O V population due to station operation should be reflected in an alteration of food habits in the largemouth bass. The 1979-1980 operational years did not appear to affect the food habits of the largemouth bass in Lake Anna. 6.4 Summary 6.4.1 Physical and Chemical
- 1. Dissolved oxygen values were generally high throughout the water column at all fish stations for 1980.
- 2. Turbidity values for the Upper Reservoir fish stations, ,
were higher than all other sampling stations. 6.4.2 Relative Abundance Based on Gill Net Observations
- 1. The gizzard shad increased ii. gill net catches since its appearance from 3.1 and 7.5% to as much as 68% of the total catch. A gradual decline in relative abundance of shad was
- noted in recent years, but 1980 showed an increase in shad
(') standing crop.
- 2. The chain pickerel has suffered a decline in numbers throughout the study.
- 3. The carp has displayed an increase in catch per day as well as kg per net day, but during 1980 a decrease was noted in catch per net day.
- 4. The creek chubsucker has declined steadily in relative abundance throughout the study period.
- 5. The brown bullhead and the yellow bullhead have shown a decrease in catch per unit effort during the study period.
- 6. The channel catfish has shown an increase in catch per unit effort.
- 7. The largemouth bass displayed a decrease in relative abundance in Lake Anna compared to 1979.
- 8. The white perch has shown a marked increase in relative abundance over the study period.
I O 6-53 1
l i O
- 9. The striped bass has shown an increase in catch per unit effort in the Lower Reservoir, however no striped bass were caught in the WHTF in 1980.
- 10. The WHTF produced lower values for kg of fish caught per net day than the other study areas in 1980 reversing the trend shown in 1978 and 1979.
6.4.3 Cove Rotenann Studies
- 1. The gizzard shad was the most important fish in terms of standing crop.
- 2. The Upper Reservoir disolayed the highest value for stand- ,
ing crop of gizzard shad.
- 3. The carp has increased in standing crop since 1979.
- 4. The creek chubsucker was collected at more stations than other suckers, but this species remains:en a steady decline.
- 5. The channel catfish has steadily increased in standing crop over the past two years in the WHTF, but no channel
(~') catfish were collected in the WHTF during the 1980 rotenone sampling.
- 6. The white perch displayed an increase in standing crop during 1980.
, 7. Higher standing crop values were obtained from the Upper ! Reservoir in 1980 than for other areas of Lake Anna as has historically been the case. 6.4.4 Gonosomatic Index of the female, Micropterus salmoides
- 1. During 1980, female bass at the Mid-Reservoir electro-fishing station displayed a peak gonad development in the third week of April, but female bass observed in the WHTF reached their peak gonad development during the first week of April.
l 2. Female bass were observed in the " squeeze ripe" or
- spawning condition in the WHTF on April 10, 1980, where-as the female bass collected in the Reservoir started '
spawning three weeks later on April 24, 1980.
'( )
6-54 i
() 4 6.4.5 Age and Growth of the largemouth' Bass, Micropterus salmoides
- 1. The 1980 Lake Anna largemouth bass population was putting on more weight with length than the national average.
- 2. The age I largemouth bass in the WHTF grew significantly
, faster than the first year bass in the other sampling locations duri.'g 1979, but displayed no significant difference durir.g 1980.
; 6.4.6 Food Habits of the largemouth Bass, Microoterus salmoides . 1. Throughout the study period from 1977-1980, it was evident -
that the family Clupeidae, represented by the single species, j Dorosoma cepedianum, was the most frequently selected forage fish in the diet of the largemouth bass in Lake Anna.
- 2. The 1979-1980 operational years did not affect the food habits of the largemouth bass.
4 6.4.7 Fish Species
! ( l. A fish species list for Lake Anna is shown in Table 6.4.7.1.
1 4 O 6-55
. , ,. . . , - - - ~ , . , , - - , ,, --. -- n
r A U TABLE 6.4.7.1 FISH SPECIEC LIST FOR LAKE ANNA, 1980 Common Name Family Genus Species American eel Anguillidae Anguilla rostrata Gizzard shad Clupeidae Dorosoma cepedianum i Eastern mudminnow Umbridae Umbra pygmaea Chain pickerel Esocidae Esox niger i Cyp ri ni dae s Carp Cyprinus caroio Golden shiner Notemigonus crysoleucas Swallowtail shiner Notropi procne Catostomidae White sucker Catostomus commersoni Creek chubsucker Erimyzon oblongus Shorthead redhorse Moxostoma macrolepidotum Ictaluridae Yellow bullhead Ictalurus natalis Brown bullhead Ictaiurus nebulosus Channel catfish Ictalurus punctatus Margined madtom Noturus insignis Percichythidae White perch Morone americana - Striped bass Morone saxatilis Centrarchidae ! Bluespotted sunfish Enneacanthus gloriosus . Redbreast sunfish Lepomis auritus Pumpkinseed Lepomis gibbosus l Warmouth Lecomis qu': sus Bluegill Lepomis macrochirus () : 1 6-56
O TABLE 6.4.7.1 (CONTINUED) FISH SPECIES LIST FOR LAKE AN N A , 1980 - Common Name Family Genus Species Centrarchidae Redear Lepomis microlophus Largemouth bass Micropterus salmoides Black crappie Pomoxis nigromaculatus Percidae Tessellated darter Etheostoma olmstedi Yellow perch Perca flavescens O O 6-57
r.- r () ' 6.5 Reference American Public Health Association; American Water Works Association. Water Pollution Control Federation. Standard methods for.the examination o# water and wastewater. 15th ed., New York: Amer. Pub. Health Assoc. ; 1975. Baker, C.D.; Schmitz, E.H. Food habits of adult gizzard shad and threadfin shad in two Uzark reservoirs. . Reservoir Fisheries ana Limnology. Spec. Publ. No. 8. Amer. Fish Soc. pp 3-11; 1971. Banner, A.; Van Arman, J. A. Thermel effects on eggs, larvae ' and juveniles of bluegill sunfish. Tech Report Office of Research and Monitoring USEPA. Wash. D.C.-111 pages; 1973. Bennett, D.H.; Gibbons, J.W. Reproductive cycles of largemouth bass (Micropterus salmoides) in a cooling reservoir. Trans. Amer. Fish Soc. 104: 77-82; 1975. Bennett, G.W. The growth of the~1argemouth black bass, Huro salmoides (Lacepede), in the waters of Wisconsin. Copeia. 1:104-118; 1937.
. Experimental largemouth bass management in Illinois. Tran. Amer. Fish Soc. 80:231-239; 1951.
. ; Adkins, H.W.; Childers, W.F., Largemouth bass and other fishes in Ridge Lake, Illinois, 1941-1963.
Ill. Nat. Hist. Sury. Bull. 30(1):1-67: 1969. Carlander, K.D. Handbook of freshwater fishery biology. Vol. 1: Ames, Iowa: Iowa State Univ. Press; 1970.
. Handbook of freshwater fishery biology. Vol. 2:
Ames, Iowa: Iowa State Univ. Press; 1977.
; Smith, L.L., Jr. Some factors to consider in the choice between standard, fork and total lengths in fishery investigations. Copeia. 1:7-12; 1945.
Dryer, W.; Benson, N.G. Observation on the influence of the new Johnsonville steam plant on fish and plankton populations. Proc.10th Annual Conference S.E. Assoc. Game and Fish f- Commission: pp 85-81; 1957. l () 6-58 l 1
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Everhart, W. H.; Eipper, A.W.; Young, W.D. Principles of fishery science. Ithaca, New York: Cornell Univ. Press; 1975. Gammon, J. R. The effect of thermal inputs on the populations of fish and macroinvertebrates in the Wabash River. Tech Report No. 32. Purdue University. Water Resources Research Center. West Lafayette, Ind.106 pages; 1973. Goldstein, R.A. Evaluation of a cooling lake fishery. First Annual Report. Ill. Nat. History Survey. Urbana , Ill . ; 1976. Hile, R. Age and growth of the rock bass Ambloolites rupestris (Rafinesque), in Nebish Lake, Wisconsin. Trans. Wisc. Acad. . Sci., Arts. Let. 33:189-337; 1941. Jenkins, R. M. Prediction of fish biomass, harvest, and prey-predator relations in reservoirs. Proc. of Conf. on Assessing the Effects of Power-Plant-Induced Mortality on Fish Populations pp 282-296; 1977. Jester, 0.8.;shad, gizzard Jensen, B.L. Life Dorosoma history (and cepedianum ecology LeSueur), of the with (]) reference to Elephant Butte Lake. Agricultural Experiment Station Research Report 218. New Mexico State Univ.; 1972. Lackey, R.T. Introductory fisheries science. Blacksburg, Va.: VPI and SU; 1974. Lagler, K. F. Capture, sampling and examination of fishes. Ricker, W.E. ed. Methods of assessment of fish population in freshwater. Oxford, Great Britian: Blackwell Sci. Publ . ; 1968. Larimore, R.W. Lake Sangchris Project. Ill . Nat. History Survey. Urbana, Ill; 1975.
; Tranquilli, J. A. Lake Sangchris Project III.
National History Survey. Urbana , Ill . ; 1977. LeCren, E.D. The determination of the age of the perch (Perca fluviati11s) from the opercular bone. J. Animal Ecol. 16. 188-204; "T747. Mansueti, A. J.; Hardy, J.D. Development of fishes of the Chesapeake Bay Region. Nat. Resour. Inst., Ur.iv., Md.; 1967. () l t 6-59
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Marcy, B. C. Fishes of the Lower Connecticut River and the effects of the Connecticut Yankee Plant. The Connecticut River Ecological Study. Amer. Fish. Soc. Spec. Pub. 1:61-114; 1976. Miller, R. R. Systematics and biology of the gizzard shad (Dorosoma cepedianum) and related fishes. Fishery Bull. No. 173(60):371-392; 1960. Neill, W.H. ; Magnuson, J.J. Distributional ecology and behav-ioral thermoregulation of fishes in relation to heated effluent from a steam electric power plant (Lake Monona, Wisconsin) Univ. of Wisc. Water Resources Center. Madison, Wisconsin; 1972. - Nicholls, A. G. The Tasmanian trout fishery. I. Sources of information and treatment of data. Aust. J. Marine and Freshwater Res. 8:451-479; 1957. Padfield, J. H., Jr. Age and growth differentiation between the sexes of the largemouth bass, Micropterus salmoides (} (Lacepede). J. Tenn. Acad. Sci. 26(1): 42-54; 1951. Prof fitt, M. A. Effects of heated discharge upon aquatic resources of White River at Petersburg, Indiana. Ind. Univ., Water Resources Res. Center Rep. Invest. No. 3. 101 p; 1969. Ricker, W. E. Methods for assessment of fish produ~ction in freshwaters. Oxford and Edenburgh: Inter. Biol. Prog. Blackwell Sci. Pub. ; 1968.
. Effects of size selective mortality anc sampling bias on estimates of growth, mortality, production and yield. J. Fish. Res. Bd. Can. 26(3):479-541; 1969
.; Merriman, D. On the methods of measuring fish.
Copeia 4:185-191; 1945. Royce, W. F. Standard length versus total length. Trans. Amer. Fish. Soc. 71:270-274; 1942. Ruell, R. ; Lorenzen, W. ; Oliver, J. Population dynamics of l young of the year fish in a reservoir receiving heated effluent. Proc. of Conf. on Assessing the Power-Plant-Induced Mortality on Fish Population. 46-70; 1977. O 6-60
{ n v Sandox, 0. Changes in the fish population of Lake Murray following the reduction of gizzard shad numbers. Proc. Okla. Acad. Sci. 174-181; 1956. Schneider, R. W. Some aspects of the life history of the gizzard shad, Dorosoma cepedianum, in Smith Mountain Lake, Virginia. M.S. Thesis. Virginia Polytechnic Institute, (Unpublished); 1969. Steel , R. G. D. ; Torrie , J. H. Principles and proceedures of statistics. New York: McGraw-Hill Book Co., Inc.; 1960. Virginia Electric and Power Company. Environmental Study of Lake Anna, Virginia: January 1, 1979 - December 31, 1979. A report of James R. Reed and Associates, Inc. to the . Virginia Electric and Power Company. March 1980. Located at Virginia Electric and Power Company, Richmond, Virginia. Weatherly, A. H. Growth and ecology of fish populations. New York: Academic Press , Inc. ; 1972. Witt, A.: Campbell , R.S. ; Whitley, J.D. The evaluation of environmental alterations by thermal loading and acid pollution in the cooling reservoir of a steam electric O station. Missouri Water Resources Research Center. Univ. of Missouri, Columbia; 1970. Yeh, C. F. Relative selectivity of fishing gear used in a large reservoir in Texas. Trans. Amer. Fish. Soc. 106(4): 309-313; 1977. Zar, J. H. Biostatistical analysis. Englewood Cliffs, New Jersey: Prentice-Hall , Inc. ; 1974. a i I 6-61}}