ML073240724

From kanterella
Jump to navigation Jump to search
Draft Environmental Assessment and Finding of No Significant Impact, Drought Contingency Plan Update Savannah River Basin
ML073240724
Person / Time
Site: Vogtle  Southern Nuclear icon.png
Issue date: 05/31/2006
From:
US Dept of the Army, Corps of Engineers, Savannah District
To:
Office of Nuclear Reactor Regulation
References
NL-07-2097
Download: ML073240724 (74)


Text

DRAFT I."...'..I MAY 2006 Prepared by: US Army Corps of Engineers Mobile/Savannah Planning Center DRAFT ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT DROUGHT CONTINGENCY PLAN UPDATE SAVANNAH RIVER BASIN::;-.-.US ARMY CORPS OF ENGINEERS SA V ANNAB DISTRICT MAY 2006 DraftEA Drought Contingency Plan Update Savannah River Basin TABLE OF CONTENTS May 2006 Page No.ACRONYMS iv FINDING OF NO SIGNIFICANT IMPACT 1 DRAFT ENVIRONMENTAL ASSESSMENT

  • ..............*..*.**.**...........***********..........*...**...........

1 1.0 PURPOSE AND NEED FOR THE PROPOSED ACTION 1 1.1.INTRODUCTION 1 1.1.1.History 1 1.1.2.Requirement for Environmental Documentation 1 1.1.3.General Objectives 2 1.2.PURPOSE AND NEED 2 1.3.SCOPE 2 1.4.STUDY METHODOLOGY 2 2.0 AFFECTED ENVIRONMENT 3 2.1.DESCRIPTION OF THE SA V ANNAB RIVER BASIN 3 2.2.DESCRIPTION OF CORPS PROJECTS 4 2.3.RECREATION 4'2.3.1:

Ramps

5.2.3.2.Swimming 8 2.4.WATER SUPPLY 8 2.5.HYDROPOWER AND PUMPED STORAGE 9 2.6.WATER QUALITY IN THE LAKES 9 2.7.WATER QUALITY IN THE SAY ANNAB RIvER 10 2.8.BIOTIC COMMUNITIES AT THE LAKEs 12 2.8.1.Fishery Resources at Hartwell Lake 12 2.8.2.Fishery Resources at RBR Lake 12 2.8.3.Fishery Resources at JST Lake 13 2.9.BIOTIC COMMUNITIES IN THE LOWER SA V ANNAB RIvER 13 2.9.1.Fish 13 2.9.2.Wetlands 15 2.9.3.Wildlife 15 2.9.4.Endangered Species 17

3.0 DESCRIPTION

OF THE PROPOSED ACTION AND OTHER ALTERNATIVES 18 3.1.ALTERNATIVE FORMULATION 18 3.2.ALTERNATIVES ANALYSIS 18 3.2.1.No Action Alternative 18 3.2.2.Alternative 1 21 3.2.3.Alternative 2 22 3.2.4.Alternative 3 22 3.2.5.Alternatives Considered But Eliminated From Detailed Consideration 23 3.2.6.Selected Alternative 23 4.0 ENVIRONMENTAL AND SOCIOECONOMIC CONSEQUENCES 23 4.1.WATER QUALITY 23 4.2.BIOTIC COMMUNITIES-LAKEs 27 4.3.BIOTIC COMMUNITIES-SHOALS 30 i DraftEA Drought Contingency Plan Update Savannah River Basin TABLE OF CONTENTS (continued)

May 2006 Page No.4.4.BIOTIC COMMUNITIES-FLOODPLAIN 34 4.5.BIOTIC COMMUNITIES-EsTUARY

36 4.6.THREATENED AND ENDANGERED SPECIES**********************************************************************************

39 4.7.RECREATION 41 4.7.1.Boat-Launching Ramps and Private Docks 41 4.7.2.Swimming 49 4.8.WATER SUPPLY 50 4.9.HYDROPOWER 56 4.10.CULTURAL RESOURCES 57 4.11.ENVIRONMENTAL JUSTICE 57 4.12.CUMULATIVE EFFECTS***************************************************************************************************************

57

5.0 CONCLUSION

......................................................................................*..............................

59 6.0 RELATIONSIDP OF PROJECT TO FEDERAL AND STATE AUTHORITIES 64 7.0 COORDINATION 64 8.0 LITERATURE CONSUL TED 65 LIST*OF TABLES Table 1: Unusable Ramps by Lake Level 658 to 652 Feet msl---------------------------------------------------5 Table 2: Unusable Ramps by Lake Level 326 to 317 Feet msl---------------------------------------------------7 Table 3: Endangered Species List-----------------------------------------------------------------------------------

17 Table 4: Hartwell Action Levels for the NAA--------------------------------------------------------------------

19 Table 5: Thurmond Action Levels for the NAA------------------------------------------------------------------

20 Table 6: Hartwell and Thurmond Action Levels for Alternative 1---------------------------------------------

21 Table 7: Hartwell and Thurmond Action Levels for Alternative 2---------------------------------------------

22 Table 8: Hartwell Lake: Days At and Below Lake Level by Alternative-------------------------------------41 Table 9: Hartwell Lake: Number of Un useable and Useable Ramps by Lake Level------------------------

42 Table 10: Hartwell Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 1 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment--------------------43 Table 11: Hartwell Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 2 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment--------------------

44 Table 12: Hartwell Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 3 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment--------------------

44 Table 13: JST Lake: Days At and Below Lake Level by Alternative


45 Table 14: Number of Un useable and Useable Ramps by Lake Level------------------------------------------

46 Table 15: JST Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 1 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment--------------------------------

47 Table 16: JST Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 2 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment--------------------------------

48 Table 17: JST Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 3 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment--------------------------------

49 Table 18: Projected Average Values for Augusta Canal Water Needs (cfs)--,.-------------------------------

52 Table 19: NAA JST Average Annual Flows by Water Year for Summer Period 52 Table 20: NAA JST Average Annual Flows by Water Year for Winter Period------------------------------

52 Table 21: NAA JST Average Annual Flows by Water Year for Spring Period------------------------------

53 11 DraftEA Drought Contingency Plan Update Savannah River Basin TABLE OF CONTENTS (continued)

May 2006 Page No.Table 22: Alternative 1 JST Average Annual Flows by Water Year for Summer Period-------------------

53 Table 23: Alternative 1 JST Average Annual Flows by Water Year for Winter Period---------------------

53 Table 24: Alternative 1 JST Average Annual Flows by Water Year for Spring Period---------------------

54 Table 25: Alternative 2 JST Average Annual Flows by Water Year for Summer Period-------------------

54 Table 26: Alternative 2 JST Average Annual Flows by Water Year for Winter Period---------------------

54 Table 27: Alternative 2 JST Average Annual Flows by Water Year for Spring Period---------------------

55 Table 28: Alternative 3 JST Average Annual Flows by Water Year for Summer Period-------------------

55 Table 29: Alternative 3 JST Average Annual Flows by Water Year for Winter Period---------------------

55 Table 30: Alternative 3 JST Average Annual Flows by Water Year for Spring Period---------------------

56 Table 31: Comparison of Effects of the No Action Alternative, Alternatives 1,2 and 3--------------------

60 Table 32: Comparison of Pool Elevations and Actions Taken for the NAA, Alternatives 1,2 and 3-----63 Table 33: Relationship of Plans to Environmental Requirements


64 LIST OF FIGURES Figure 1: Hartwell Action Levels for the NAA-------------------------------------------------------------------

19 Figure 2: Thurmond Action Level for the NAA------------------------------------------------------------------

20 Figure 3: Hartwell Action Levels for Alternatives 1, 2 and 3---------------------------------------------------

21.--Figure 4: Thurmond Action Levels for Alternatives 1,2 and 3----.:.:.:-----------

...------...

22 Figure 5: Example of Downstream Hydrographs


24 Figure 6: Example of Pool Elevation Tables----------------------------------------------------------------------

28 LIST OF APPENDICES AppendixA-Savannah River Basin Maps AppendixB-Clearance from Cultural Resources Management AppendixC-Joint Public Notice and News Release AppendixD-Comments AppendixE-List of Pre parers AppendixF-HEC-ResSim Pool Plots 111 DraftEA Drought Contingency Plan Update Savannah River Basin ACRONYMS CFR--------------

Code of Federal Regulations cfs----------------

cubic feet per second DHEC-----------

Department of Health and Environmental Control DNR-------------

Department of Natural Resources DO---------------

Dissolved Oxygen EA----------------

Environmental Assessment EFM-------------

Ecosystems Function Model EPA--------------

Environmental Protection Agency EPD--------------

Environmental Protection Division HEC--------------

US Army Corps of Engineers Hydrologic Engineering Center JST---------------

J.Strom Thurmond msl---------------

mean sea level NAA-------------

No Action Alternative NEP A------------

National Environmental Policy Act of 1969 NOAA-----------

National Oceanic and Atmospheric Administration NSBL&n..

Savannah Bluff-Lock and Dam NWR-------------

National Wildlife Refuge PDT--------------

Project Delivery Team RBR--------------

Richard B.Russell SEP A------------

Southeastern Power Administration SHPO------------

State Historic Preservation Officer SRBDCP--------Savannah River Basin Drought Contingency Plan USFWS----------

United States Fish and Wildlife Service USGS------------

United States Geologic Survey iv May 2006 DraftEA Drought Contingency Plan Update Savannah River Basin FINDING OF NO SIGNIFICANT IMPACT Name of Action: Drought Contingency Plan Update for the Savannah River Basin May 2006 1.Description of the Proposed Action The Proposed Action is Alternative 2.It consists of retaining major components of the 1989 Savannah River Basin Drought Contingency Plan (SRBDCP)and adding other features.The discharge restrictions at J.Strom Thurmond (JST)Dam will be allowed to transition back to higher flows prior to reaching full pool.A two-foot buffer will be used to simulate engineering judgment to distinguish a lasting drought recovery from a temporary increase in inflows.The minimum daily average release at Thurmond will be adjusted from 3600 cubic feet per second (cfs)to 3800 cfs, and a maximum daily average release of3800 cfs will be specified in drought level 3.Four Eumped storage units are also available at Richard B.Russell Dam June 1 5t through September 30.Reservoir modeling of all alternatives includes 80 unit hours of pumping per week, which is the amount that is required to support the current hydropower contract.Pumping beyond 80-unit hours up to the maximum allowed by the Richard B.Russell Dam and Lake Project Pumped Storage Environmental Assessment of August 1999 can still occur when economically feasible.Reservoir modeling was conducted to ensure that outflows at Thurmond Dam and flows at Augusta did not fall below 3600 cfs.Additionally, the maximum weekly_

at J: Strom Thyrmond Dam woyld be 4200 cfs IDld 4000 c:fs for drought levels 1 and 2, respectively

....2.Other Alternatives Considered Alternatives to the Proposed Action were developed as part of the planning process.The alternatives for consideration were as follows: a.No Action Alternative (Continue with the 1989 Savannah River Basin Drought Contingency Plan (SRBDCP))b.Alternative 1: Consists of retaining the major components ofthe 1989 SRBDCP and adding several other features.The discharge restrictions at Thurmond were allowed to transition back to higher flows prior to reaching full pool.A two foot buffer was used to simulate engineering judgment to distinguish a lasting drought recovery from a temporary increase in inflows.The minimum daily average release at Thurmond was adjusted from 3600 cfs to 3800 cfs, and a maximum daily average release of 3800 cfs was specified in drought level 3.Drawdown dates at Hartwell and Thurmond would also be synchronized as listed in Table 6.Action thresholds are shown in Figure 3 and Figure 4.c.Alternative 3: Includes all components of Alternative 2 (Proposed Action), but the daily average release at Thurmond for Level 3 would be 3600 cfs.d.Alternatives Considered but Eliminated from Detailed Consideration:

Several Project Delivery Team meetings and Stakeholder meetings were held in late 2004 through the Spring of 2005 with possible alternatives discussed.

At the 4 March 2005 Stakeholders meeting in Evans, Ga.the alternatives were prioritized by the stakeholders in a rating process allowing some alternatives to be eliminated from further consideration.

Alternatives eliminated included: increasing the flows when return elevations hit one foot above the elevation triggers, increasing the number of drought triggers for drought 1 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 management and return from a drought to provide a more gradual transition to 3600 cfs, lowering the minimum drought trigger 3 releases to 3300 or 3000 cfs with 3600 cfs being maintained at the New Savannah Bluff Lock and Dam, adjusting Level 3 elevations at Hartwell from 646 to 648 or 649 and adjusting Level 3 elevations at JST from 316 to 318 or 319.3.Coordination Savannah District has coordinated this action with Federal, State and Local agencies and issued a Notice of Availability to solicit comments from the public on the Draft Environmental Assessment.

4.Conclusion Based on a review of the information contained in this Environmental Assessment (EA), I have determined that the preferred alternative is the best course of action.I have also determined that the Drought Contingency Plan Update for the Savannah River Basin is not a major Federal action within the meaning of Section 102(2)(c)of the National Environmental Policy Act of 1969.Accordingly, the preparation of an Environmental Impact Statement is not required.My determination was made considering the following factors discussed in the EA to which this document is attached: a.The proposed action would not adversely impact any threatened or endangered species.b.The proposed action would not adversely impact cultural resources.

c.The proposed action would result in no adverse impact to air quality.d.The proposed action complies with Executive Order 12898,"Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations." e.The proposed action would not directly affect wetlands, or cause any adverse impacts to wetlands.f.No unacceptable adverse accumulative or secondary impacts would result from the implementation of the proposed action..5.Findings The proposed action to revise the Drought Contingency Plan for the Savannah River Basin would result in no significant environmental impacts and is the alternative that represents sound natural resource management practices and environmental standards.

Date Mark S.Held Colonel, US Army Commanding 2

DraftEA Drought Contingency Plan Update Savannah River Basin DRAFT ENVIRONMENTAL ASSESSMENT

1.0 PURPOSE

AND NEED FOR THE PROPOSED ACTION 1.1.INTRODUCTION May 2006 1.1.1.History From 1986 to 1989, the previous drought of record created severe water shortage conditions over extensive areas of the Southeastern United States.At the three US Army Corps of Engineers'(Corps)impoundments on the Savannah River (Hartwell, Richard B.Russell and J.Strom Thurmond), inflows were the lowest recorded this century.The severity of the drought created conditions which stressed the traditional management concepts followed in regulating the individual Corps impoundments and the integrated water management of the three lakes.Concerns and conflicts over competing water issues intensified as drought conditions became more severe and lake levels continued to fall.During 1986, the Savannah District developed.

a Short-Range Drought Water ManagemenLStrategy to address.the_._worsening water shortage conditions in the Savannah River Basin.That document served as a guide for using the remaining storage in the Corps operated Savannah River impoundments for the duration ofthe drought.The short-range strategy also served as a prelude to the development of a long-term drought strategy, the Savannah River Basin Contingency Plan (SRBDCP)of March 1989.In May of 1998, hydrometerologic conditions in the Southeast US transitioned from extremely wet to drier than normal.The unprecedented dry conditions persisted until fall 2002 resulting in a new drought of record for the Savannah River Basin.During this extended drought period, pool elevations declined to an extent that it became conservation measures beyond those included in the SRBDCP were necessary.

A series of public meetings pushed for an update of the existing drought plan.The Savannah River Basin Comprehensive Study (SRBC), authorized in the Water Resources Development Act of 1996, became the vehicle for evaluating and implementing changes to the SRBDCP.Phase I efforts ofthe SRBC focused on delivering these changes.1.1.2.Requirement for Environmental Documentation An Environmental Assessment (EA)is prepared in conformance with procedures established by the National Environmental Policy Act of 1969 (NEPA)to identify impacts expected to result from implementation of a proposed action.The assessment ensures that the decision-maker is aware of the environmental impacts of the action prior to the decision to proceed with its implementation.

This Act requires the consideration of environmental impacts of a"Proposed Action" anditsalternatives prior to implementing the action.This EA addresses proposed updates to the SRBDCP.1 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 0*-.1.1.3.General Objectives The objectives of the Proposed Action are: c:>Savannah River Basin-apply the lessons learned from the new drought of record to improve water supply for as many users as possible and minimize negative impacts to other users adversely affected by such improvements.

c:>Environmental Compliance

-comply with all applicable environmental laws, regulations, and policies 1.2.PURPOSE AND NEED The 1998 to 2002 drought has become the new drought of record for the Savannah River Basin due to its unprecedented duration.The SRBDCP was intended to be a dynamic document which can be changed as new drought periods occur.Items that were mentioned in the Plan that may be cause for changes included: additional experience, further studies of salinity intrusion in Savannah Harbor, changing water supply needs, improvements to water intakes and the uncertain future operational plan at the Savannah River Site.This proposed modification of the SRBDCP is in conjunction with the ongoing Savannah River Basin Comprehensive Study...

The scope of this EA is limited to assessing the potential environmental and socio-economic effects resulting from implementing the Proposed Action and the alternatives.

After the elimination of alternatives that were not considered feasible or effective, the potential environmental impacts associated with the No Action Alternative (NAA)are compared to other alternatives that include the Proposed Action.1.4.STUDY METHODOLOGY Study alternatives were simulated using the HEC-ResSim reservoir operations model developed by the Hydrologic Engineering Center in Davis, California.

All simulations ran from October 1, 1997, to September 30,2003, to cover the new drought ofrecQId for the Savannah River Basin.The United States Geologic Survey (USGS)derived unregulated inflow data for the drought period which was used as input in ResSim.Lake levels were still used as a triggering mechanism for action because they are readily understood by the public, are already used by climatologists to defme drought, and do not require complex forecast based calculations.

Water supply estimates from 2003 were used at appropriate locations in the model.The base condition for the study, or NAA, was initially modeled to provide a baseline from which to evaluate proposed management changes.The base condition follows the existing water release procedures described in the SRBDCP.Pumped storage operation was important to include in the NAA because this feature was not available during the original implementation of the SRBDCP in 1989.Alternatives to the NAA were then modeled to analyze their effect during the period of record drought simulation.

2 DraftEA Drought Contingency Plan Update Savannah River Basin 2.0 AFFECTED ENVIRONMENT 2.1.DESCRIPTION OF THE SA V ANNAB RIvER BASIN The Savannah River basin has a surface area of about 10,577 square miles, of which 5,821 square miles are in Georgia, 4,581 square miles are in South Carolina arId 175 square miles are in North Carolina.The basin includes portions of 27 counties in Georgia, 13 counties in South Carolina arId four counties in North Carolina.Although the basin is predominarItly rural, metropolitan areas are experiencing significarIt growth arId development pressures.

The growth is occurring primarily in the areas of Augusta arId.Sayann.ah,_

Georgia, ,althou&4 many_.cities and towns are also growing.The study area drains portions of three physiographic provinces:

the Blue Ridge Mountains, the Piedmont the Coastal Plain.In its middle arId upper reaches the river flow is regulated by several reservoirs, including three large multipurpose Corps projects (Hartwell Lake, Richard B.Russell (RBR)Lake arId J.S.Thurmond (JST)Reservoir) and two large private power reservoirs (Lakes Keowee and Jocassee).

May 2006 Water discharge in the Savannah River varies considerably both seasonally arId annually, even though it is largely controlled by releases from the Corps'JST Dam located about 20 miles northwest of Augusta, Georgia.Discharge is typically high in winter arId early spring arId low in summer and fall, but regulation by upstream reservoirs has reduced natural flow variations.

At the New Savannah Bluff Lock arId Dam 12 miles downstream of Augusta average discharge is about 10,000 cfs.The rarIge in water year 1998 was about 4,300 cfs to 42,700 cfs.Average discharge at Clyo (Effmgham County, Georgia)is 12,040 cfs with a rarIge for water year 1998 of 6,280 cfs to 52,600 cfs (Cooney et al.1999).Tidal effects extend upstream to approximately river mile 45.3 DraftEA Drought Contingency Plan Update Savannah River Basin 2.2.DESCRIPTION OF CORPS PROJECTS The Corps maintains and operates three large multipurpose projects in the basin.Hartwell Dam and Lake (55,950 acre summer pool)is located 89 miles upstream of Augusta and was filled in 1962.RBR Dam and Lake (26,650 acre summer pool)is located 59 miles upstream of Augusta and was filled in 1984.JST Dam and Lake (70,000-acre summer pool)is located 22 miles upstream of Augusta and was filled in 1954.The authorized project for the Savannah River between Augusta and Savannah, Georgia, provides for a navigation channel 9 feet deep and 90 feet wide from the upper end of Savannah Harbor (mile 21.3)to the head of navigation just below the 13th Street bridge in Augusta (mile 202.2).This is a distance of 180.9 miles.The project also includes the.lock and dam at New Savannah Bluff, located about 12 miles downstream from Augusta.Channel modifications,including-deepel1ing;-widening,snaggilli, construCtion of.bend cutoffs, and construction of pile dikes, have been made on the river to provide the 9-foot depth.However, by 1980, shipping on the river had virtually ceased, and channel maintenance was discontinued.

The existing authorized Savannah Harbor navigation project provides for a channel 44 feet deep and 600 feet wide across the ocean bar;42 feet deep and 500 to 600 feet wide to the vicinity ofK.ings Island Turning Basin;and 30 feet deep and 200 feet wide to a point 1,500 feet below the Houlihan Bridge (Highway 17).The terminus of the existing channel for Savannah Harbor is at approximately river mile 21.The project provides turning basins for vessels at various locations in the harbor.2.3.RECREATION The lakes of the Savannah River Basin provide excellent opportunities for water resources-based recreation.

However, in times of drought, when the lake levels of Hartwell and JST Lake drop 6 feet below summer pool, drought information sheets are disseminated to the public instructing them to only use marked navigation channels since unmarked hazards more prevalent increasing risks of boating accidents outside the channel.In addition, 4 May 2006 Hartwell Lake and Dam R.B.Russell Lake and Dam J.S.Thurmond Lake and Dam New Savannah Bluff Lock and Dam DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 at 6 feet below summer pool, designated swimming areas become dry.However, adverse impacts become noticeable at designated swimming areas when lake levels drop below 3 feet.According to the Savannah River Basin Water Use Data Collection Presentation of Findings, June 2004, conduct by Zapata Engineering.

P.A., for the US Army Corps of Engineers, Savannah District, during periods oflow water, approximately 39 percent of the recreational users surveyed said that they would make a water-based recreational trip to the same lake, 41 percent would make a water-based recreation trip elsewhere, and 20 percent would not make a water-based recreation trip.Therefore, during periods of drought, 61 percent of non-drought visitors do not make a water resources-based recreation trip to Hartwell and JST Lakes.Respondents of this survey also indicated that their recreational activities are seriously impacted when lake levels drop an average of 7.5 feet below full pool.According to some lake managers, water recreation is more difficult and less convenient during periods of drought because recreationists may have to travel further distances to a useable ramp for access to the lake, they may consider the lake aesthetically unpleasing and they may recognize the increased risk of damaging their boat and person.2.3.1.Public Boat-Launching Ramps and Private Docks._

ramPsp!ivate d().cJ<:s re9reational access to..the lakes?f the_._Savannah River Basin.....-Hartwell Lake There are 95 public boat-launching ramps and marinas located on Hartwell Lake.From lake elevation 660 to 658.01 feet mean sea level (msl)all ramps are useable.At and below lake level 658 feet msl, the fIrst 6 boat-launching ramps become unusable.At and below lake level 657 feet msl, 6 more or a total of 12 boat-launching ramps become unusable.At and below lake level 656 feet msl, one more or a total of 13 boat-launching ramps become unusable.At and below lake level 655 feet msl, 3 more or a total of 16 boat-launching ramps become unusable.At and below lake level 654 feet msl, 1 more or a total of 17 boat-launching ramps become unusable.At and below lake level 653 feet msl, 6 more or a total of23 (24.2percent)public boat ramps become unusable, but 72 (75.8 percent)remain serviceable.

When lake levels drop to 646 feet msl, 43 (45.2 percent)boat-launching ramps become unusable.Iflake levels were to ever drop to 638 feet msl, all the ramps become unusable.Table 1: Unusable Ramps by Lake Level 658 to 652 Feet msl Name Of Boat Ramp Lake Level Ramp Becomes Unusable Sadlers Creek State Pk.658.0 Tugaloo State Lower 658.0 Jacks Landing, SC 658.0 Holders Access, SC 658.0 Lakeshore 658.0 Mountain Bay 658.0 Reed Creek, GA 657.5 Rocky Ford, GA 657.5 5 DraftEA Drought Contingency Plan Update Savannah River Basin Name Of Boat Ramp Lake Level Ramp Becomes Unusable Brown Road, SC 657.0 Hurricane Creek, SC 657.0 Seneca Creek, SC 657.0 Walker Creek, GA 657.0 Cove Inlet, SC 656.5 Durham, SC 655.7 South Union, SC 655.5 Bradberry, GA 655.0 Timberland, SC 654.0 Darwin Wright City Pk.653.0 Tillies, SC 653.0 White City, SC 653.0 Barton Mill, SC 653.0 Port Bass, SC 653.0 Seymour, GA 653.0 Paynes Creek (inner right)652.6 Paynes Creek (left)652.6"Big,OakLeftLane (New)...,.652..5-_..'.','-,,,...Tabor, SC 652.5 Townville, SC 652.3 Twelve Mile (new left lane)652.0 Eighteen Mile Creek 652.0 May 2006 There are approximately 10,500 private boat dock permits issued on Hartwell Lake.This number is almost double of what was reported in the March 1989 SRBDCP.In that report, it was roughly estimated that about 50 percent of the docks were unusable below lake level 652 feet msl and about 90 percent were unusable at 643 feet msl.Even with the ability and willingness to chase the water, the percentage of docks now unusable at 652 feet msl would likely be greater than 50 percent since more developments are located adjacent to shallow cove areas.RBRLake There are approximately 30 public boat-launching ramps on RBR Lake.All of these ramps are useable until lake levels reach 466 feet msl.Lake levels at RBR Lake do not drop more than five feet below full pool.Therefore, public boat-launching ramps on RBR Lake were not adversely impacted during the drought of record.JSTLake There are 84 public boat-launching ramps and marinas located on JST Lake.Above lake elevation 326 feet msl to 330 feet msl all ramps are useable and allow for the launching of boats with up to 3 feet of draft.At and below lake level 326 feet msl, the first boat-launching ramp becomes unusable.At and below lake level 325 feet msl, 4 more or a total of 5 boat-launching ramps become unusable.At and below lake level 324 feet msl, 7 more or a total of 12launching ramps become unusable.At and below lake level 323 feet msl, 5 more or a total of 17 6 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 (20 percent)boat-launching ramps become unusable while 67 (80 percent)remain useable.At and below lake level 317 feet msl, 33 (39percent)boat-launching ramps become unusable.At and below lake level 315 feet msl, 46 (55 percent)boat-launching ramps become unusable.All boat-launching ramps would become unusable at 306 feet ms!.Table 2: Unusable Ramps by Lake Level 326 to 317 Feet mslName Of Boat Ramp Lake Level Ramp Becomes Unusable HwY 28 Access Ramp 326.0 Long Cane Creek Ramp 325.7 Catfish Ramp 325.5 Calhoun Falls Ramp.325.0 Broad River Campground 325.0 Double Branches Ramp 324.8 Cherokee Recreation Area (2 lanes)324.7 Mistletoe State Park (2 lanes)324.2 Soap Creek Park 324.0 Little River Quarry Ramp 324.0 SC.9tts F.eITY (New RarI).p)..,.-'",....-323.8-..-Leroys Ferry Campground 323.6 Clay Hill Campground 323.5 Winfield Subdivision (2 lanes)323.1 Mt Pleasant Ramp 322.4 Bussey Point 321.0 Chamberlain Ferry Ramp 321.0 Modoc Campground 321.0 Murray Creek Ramp 321.0 Parkway Ramp 321.0 Fishing CreekIHwv 79 Ramp 320.7 Soap Creek Subdivision 320.0 Scotts Ferry (New Ramp)318.8 Wildwood Park 318.4 Cherokee Recreation Area (2 lanes)318.2 Soap Creek Marina 318.0 Raysville Marina 317.6 Soap CreekIHwY 220 Ramp 317.0 There are approximately 1,500 private boat docks on the JST Lake.This is a 25 percent increase from the SRBDCP report.In that report, at 322 feet msl, about 50 percent ofthe docks were considered unusable.At 313 feet msl, 95 percent of the private docks were considered as unusable.Even with the ability and willingness to chase the water, the percentage of docks now unusable at 322 feet msl would likely be greater than 50 percent since newer developments are located in shallower coves.7 DraftEA Drought Contingency Plan Update Savannah River Basin 2.3.2.Swimming Swimming areas are mainly utilized from May through September.

May 2006 Hartwell Lake At Hartwell Lake, there are 22 Corps of Engineer's operated swimming beach areas located in 13 recreation areas.When lake levels reach 654 feet msl, all designated swimming areas are dry.However, when the lake level drops below 657 feet msl, swimming areas become less desirable due to the reduced water area available for swimming.When this happens, swimming occurs outside the designated swimming area increasing the risk of fatalities.

During the 1986 drought, when swimming beaches were unusable, recreation fatalities for swimming activities increased from three to nine.They fell to zero when the beaches were back in service in 1987.RBRLake At RBR, there are no Corps of Engineer's operated designated swimming areas.JSTLake At JST Lake, there are 18 Corps of Engineer's operated swimming beach areas.When lake levels reach 324 feet msl, the designated swimming areas are dry.However, when the lake level**-'C'...dIo..ps belgw}2}

3reas beaches less PJte tQ the redl,lce<;l--water area available for swiri:uning.

When this happens, swi.mrJ1ing occurs outside the designated swimming area increasing the risk of fatalities.

2.4.WATER SUPPLY Hartwell Lake There are 8 water supply users on Hartwell Lake.The highest intake elevation according to the SRBDCP, March 1989, is 638.33 feet msl.RBRLake There are 6 water supply users on RBR.The highest intake elevation according to the SRBDCP, March 1989, is 457.5 feet msl.JSTLake There are 8 water supply users on JST Lake.The highest intake elevation according to the SRBDCP, March 1989, is 307 feet msl.Downstream of JST Lake Major water supply users downstream are the Augusta Canal and Shoals.Users with intakes in the New Savannah Bluff Lock and Dam (NSBL&D)pool include North Augusta, Mason's Sod, Kimberly Clark, Urquhart Station, PCS Nitrogen, DSM Chemical and General Chemical.Users below NSBL&D include the Beaufort-Jasper County Water Supply Authority, the City of Savannah M&I Plant, the Savannah National Wildlife Refuge and many other cities and municipalities.

These water supply users currently require a minimum normal flow from JST of 3,600 cfs.8 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 2.5.HYDROPOWER AND PUMPED STORAGE The Southeastern Power Administration (SEP A)markets hydropower generated at Hartwell, RBR and JST lakes and dams.SEP A markets the energy through contracts negotiated between SEP A and certain preference customers.

There are ten hydropower facilities included in the contract that provide the energy and capacity requirements ofthe contract.These projects are located in the Savannah, Alabama-Coosa, and Apalachicola-Chattahoochee-FI4It Basins.Under normal conditions, if a certain basin or portion of a basin is unable to meet the demands expected, then that shortage can usually be transferred to, or"made up" in, another basin.However, a drought of record situation that adversely impacts all three basins will affect SEPA's ability to meet the minimum contract requirements.

SEP A may purchase replacement energy for the system generation when the Corps does not generate enough power to meet the requirements ofSEPA's contract.The RBR Pumped Storage Project began commercial operation in July 2002.Current operation of the four pumped storage units includes several operational restrictions to minimize fish entrainment and fishery habitat impacts.These operational restrictions include:>Pumped storage operations will occur only during the hours beginning one hour after official sunset to one hour before official sunrise.>..PUmped storage" openltlons will inClude a maximum of one unifoperation in March and no pumped storage operations in April.>Pumped storage operations will include a maximum of one unit operation from May 1 to May 15;a maximum of one unit operation from May 16 to May 31, except when a Level I drought is declared in accordance with this plan, during which time a maximum of two pumped storage units may be used.There shall be no seasonal pumped storage operational restrictions when a Level II drought is declared in accordance with this plan.>From May 16 to May 31, the District will conduct a minimum of six unit hours of generation, of not less than 60 megawatts, within the twelve hours preceding any two unit pumped storage operation.

From June 1 to September 30, the District will conduct a minimum of six unit hours of generation, of not less than 60 megawatts, within the twelve hours preceding any pumped storage operation; In addition to the restrictions above, all other operational and monitoring restrictions outlined in the August 1999, Final Environmental Assessment and FONSI for the Richard B.Russell Dam and Lake Project, Pumped Storage, will remain in effect.2.6.WATER QUALITY IN THE LAKES Generally, water quality in the lakes is at or above State Water Quality Standards.

However, like most deep reservoirs in the southeastern United States, they experience thermal stratification.

This natural phenomenon results from the difference in densities between the surface and subsurface water caused by the temperature variation in the water column.As the tributary and surface waters warm, the difference in density between the surface and bottom waters begins to restrict vertical circulation of the lake.The result of this restriction of circulation is the development of three layers of water: the epilimnion, the well-mixed surface layer which receives oxygen from interaction with the atmosphere; the hypolimnion, the bottom strata which 9 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 is essentially stagnant water in which the dissolved oxygen (DO)is slowly utilized by the respiration and decomposition of organic matter;and the thermocline, which is the transition between the upper and lower strata and which exhibits the maximum temperature gradient.The stability of thelakeduring stratification increases throughout the summer months as the density gradient intensifies.

As winter approaches, cooling of the surface waters causes them to become more dense.When temperatures are sufficiently reduced, these waters fall below the thermocline, thereby breaking the stratification.

After the fall"overturn," the lake becomes isothermal, with free circulation of water throughout the lake.For example, thermal stratification begins in Hartwell Lake in late April and early May of each year.The thermocline is established at a depth of about 30 feet and is maintained atthatdepth through early August.The thermocline moves to a depth of about 40 feet in late August/early September and to about 50 feet inlateSeptember/early October.In late October/early November, as the lake"overturns," the thermocline moves to a depth of about 70 feet and the lake becomes isothermal by early December.The hypolimnion is typically below the euphotic zone and, lacking free circulation with surface waters, has no potential to renew DO concentrations which are gradually exhausted through*respirati6n and decomposition.

As the DO concentrations" decrease, a maxim'uniDO"gdldient*

develops in the area of the thermocline.

The DO of the top layer remains relatively constant, about 7 mg/l, as the DO of the bottom layer decreases.

The level of the maximum DO concentration gradient is established at a depth of about 30 feet in July, moves to a depth of about 40 feet in August, and to 55 or 60 feet in late September.

By the first of August, there is usuallya3 mg/l difference between the DO in the upper and lower layers;and by the middle of September, the DO in the lower layer can range between 0 and 2 mg/I.The water quality of the lower layer continues to deteriorate until the fall"overturn" occurs.As"overturn" occurs, the level of the maximum DO concentration gradient falls to 80 feet in October and near the lake bottom in early December, after which the DO concentration is nearly the same at all levels until the following RBR Lake utilizes a hypolimnetic DO system that maintains DO concentrations at or above 5 mg/lthroughout the year.Because water released through Hartwell Dam for hydropower comes from the low DO layer, negative effects on the aquatic environment in the Hartwell tailwater area can result.The Corps has installed modifications, referred to as"turbine venting", that allow air to be diffused into the water as it flows past the turbines during generation.

The result is a much needed increase of at least 2 mg/l in dissolved oxygen levels in the tailwater.

DO concentrations of the release waters from Hartwell can be expected to be below 5 mg/l from late summer through early fall, with the lowest readings from August through September.

2.7.WATER QUALITY IN THE SAVANNAH RIvER The Savannah River below JST Dam is classified as"Freshwater" by the South Carolina Department of Health and Environmental Control (DHEC).This designation is defmed as: 10 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006"Freshwaters suitable for primary and secondary contact recreation and as a source for drinking water supply after conventional treatment in accordance with the requirements of the Department.

These waters are suitable for fishingandthe survival and propagation of a balanced indigenous aquatic community of fauna and flora.This class is also suitable for industrial and agricultural uses." The Georgia Environmental Protection Division (EPD)of the Georgia Department of Natural Resources (DNR)has classified the main river as"Fishing" waters.The water quality standards for dissolved oxygen, as stated in Georgia's Rules and Regulations for Water Quality Control (GA EPD, 2004), Chapter 39l-3-6-.03(6)(c)(i), that this classification requires are: "A daily average of 5.0 mg/L and no less than 4.0 mg/L at all times for waters supporting warm water species offish".Aquatic life and recreational uses are generally fully supported along the main length of the Savannah River.South Carolina DHEC issued a fish consumption advisory in 1996 for the main Savannah River (Thurmond Dam to Interstate 95)because of concerns about mercury,137, and Strontium-90.

These concerns stemmed from historic methods of disposal of radioactive materials at the Savannah River Site.Historically, summer discharges from Thurmond Dam have low in both DO and temperature.

Savannah District hasreplacedsix of the seven turbines with a self-aspirating design and replacement is underway on the seventh turbine.This adds oxygen to the discharges increasing their DO levels during the summer months.The District expects to complete installation of a DO injection system within Thurmond Lake in 2007-2009.

This system would ensure that waters reaching the dam contain about 3 parts per million (ppm)of DO.With the combination of these two actions, discharges from Thurmond Dam are expected to contain at least 5 ppm of DO throughout the year.That level would meet both the Georgia and South Carolina standard for DO levels for those waters.South Carolina DHEC classifies the estuarine portion of the river as SB: "Tidal saltwaters".

This designation is defined as: "...suitableprimarily for primary and secondary contact recreation, crabbing and fishing.These waters are not protected for harvesting of clams, mussels, or oysters for market purposes or human consumption.

The waters are suitable for fishingandthe survival and propagation of a balanced indigenous aquatic community of marine fauna and flora." The Georgia EPD has classified the estuarine portion of the river as"Coastal Fishing." Seasonal DO sags occur in the summer months in the estuarine portion of the river.The Environmental Protection Agency (EPA)is fmalizing a draft Total Maximum Daily Load (TMDL)that was prepared in August of 2004 for the Savannah River from Augusta to the coast forDO.11 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 The State of South Carolina uses a minimum of 3600 cfs at the Savannah River Augusta gage for the permitting of point source discharges on the River, while the State of Georgia uses the 7Q10 values of 3800 cfs at the Augusta gage, 4160 cfs further downstream at the Millhaven gage and 4710 cfs at the Clyo gage.2.8.BIOTIC COMMUNITIES AT THE LAKES 2.8.1.Fishery Resources at Hartwell Lake Hartwell Lake and its tailrace provide a vast habitat for both warmwater and coldwater fisheries.

The lake area supports a large warmwater fishery including such species as white and striped bass, hybrid bass, largemouth bass, bluegill, pumpkinseed, redear sunfish, yellow perch, sauger, walleye, and catfish.Nongame species found within the lake include blueback herring, carp, longuose gar, redhorse and spotted sucker.The GADNR and SCDNR both actively stock, on average, 500,000 to 1,000,000 striped bass and hybrid bass in Hartwell Lake.The Hartwell tailrace supports a coldwater put and take trout fishery that is supported by stocking from both States.The State of Georgia, DNR, EPD has the Savannah RiverinHart County (which includes the Hartwell tailrace)classified as Secondary Trout Waters.These waters are described as.__those:waters in,which there is no.evidence of reproduction, but they are capable of..supporting trout throughout the year.Striped bass and walleye are also found in this coldwater fishery.Study findings indicate that blueback herring habitat becomes quite restricted during lake stratification due to the DO and temperature requirements of the fish.The results of these stratification conditions are the congregation of herring in the penstock area and fish kills from entrainment (Alexander, et.al., 1991).Operational changes by Savannah District have been implemented to alleviate or minimize this entrainment.

2.8.2.Fishery Resources at RBR Lake The fishery resources ofRBR have been extensively studied.The Savannah District along with the University of Georgia Cooperative Fish and Wildlife Research Unjt (GA COOP)began baseline studies of fishery*resources in RBR Lake in 1990.These studiesiIicluded cove rotenone sampling, gill net sampling, electrofishing, and telemetry.

The Savannah District has also conducted hydroacoustic surveys of the fishery resources in the RBR tailrace since 1986, and lakewide hydroacoustic surveys ofRBR Lake in 1997.The South Carolina DNR has conducted fisherman creel surveys on RBR since 1991.The Georgia DNR has conducted.fisherman creel surveys in the RBR tailrace since 1988.RBR Lake supports a wide variety of fish species.The more common species include;largemouth bass, spotted bass, redeye bass, threadfm shad, gizzard shad, blueback herring, bluegill, redear sunfish, channel catfish, brown bullhead, black crappie, yellow perch, white perch, spotted sucker and common carp.Small numbers of hybrid bass (striped bass x white bass)and striped bass are caught each year in RBR Lake.12 DraftEA Drought Contingency Plan Update Savw:mah River Basin May 2006 2.8.3.Fishery Resources at JST Lake The fishery resources of JST have been extensively studied.The Savannah District along with the GA COOP began baseline studies of fishery resources in JST Lake in 1986.These studies included cove rotenone sampling, gill net sampling, electrofishing, and telemetry.

The Clemson University Cooperative Fish and Wildlife Research Unit (CU COOP)conducted a commercial creel estimate and a population estimate of blueback herring.The Savannah District has conducted lakewide hydroacoustic surveys of the forage fish populations in 1996andthe South Carolina DNR has conducted fisherman creel surveys on JST since 1991.The more common fish species in JST Lake include;largemouth bass, bluegill, redear sunfish, hybrid bass, striped bass, black crappie, brown bullhead, channel catfish, flathead catfish, white perch, yellow perch, threadfm shad, gizzard shad, and blueback herring.The South Carolina DNRandGeorgia DNR both actively stock hybrid bass and striped bass in JST Lake.On average, 750,000 to 1,000,000 striped and hybrid bass have been stocked annually in JST Lake.The RBR tailrace supports a substantial fishery for striped bass, hybrid bass, and white perch.This area makes up only 2 percent of the surface area of JST Lake, but accounts for 9-11 percent of the total harvest of these species.Fish abundance in the RBR tailrace generally peaks in the.

is lower in winter.A 90]Jlll1ercia.t fishery-for blueback herriIlg exi.stsJ)J the RBR Taihvater.

Blueback herring are used by fishemlen as bait in both Georgia and South Carolina.Recreational fisherman also net blueback herring in the RBR tailrace and in JST Lake for their personal use as bait.2.9.BIOTIC COMMUNITIES IN THE LOWER SA V ANNAB RIvER 2.9.1.Fish Riverine fish habitats in the Savannah River have been highly modified or converted to lacustrine habitat by construction of major dams and reservoirs inundating the upper half of the River Basin.This large-scale habitat conversion has changed the relative abundance and diversity of fish species from a system dominated by migratory diadromous fish to more localized riverine and lacustrine-dominated fish communities.

A comprehensive five year fishery survey of existing coastal plain habitats concluded that the lower Savannah River supports an abundant, diversified fish community, but has a low to moderately utilized fishery (Schmitt and Hornsby 1985).Based on numbers and weight collected the most abundant game fish were largemouth bass, chain pickerel, black crappie, yellow perch, redbreast sunfish, bluegill, redear sunfish, warmouth, flier, and pumpkinseed.

Important non-game fish include longnose gar, bowfm, white catfish, channel catfish, common carp, spotted sucker, silver redhorse, robust redhorse, striped mullet, and brown bullhead.In numerical terms the most important forage fish are gizzard shad and a number of minnow species.Diadromous fishes inhabiting the lower Savannah River include striped bass, American shad, hickory shad, blueback herring, shortnose sturgeon, Atlantic sturgeon,andthe catadromous American eel.The present-day Savannah River population of striped bass appears to be more riverine in its habitat use patterns than more northern populations that are truly anadromous.

13 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Prior to construction of mainstem Savannah Dams from 1840 to 1984 diadromous fish migrations extended throughout the Piedmont.Historical records document the upstream migration of shad and striped bass to the headwaters ofthe Savannah River, through the Tugaloo River and up the Tallulah River to Tallulah Falls, Georgia, approximately 384 river miles from the ocean.Sturgeon is known to have migrated well into the Piedmont.After 1846 the Augusta Diversion Dam acted as a barrier to inland migration of diadromous species except during high flow periods when the Damwasovertopped, allowing fish to continue unimpeded migrations.

Completion of the New Savannah Bluff Lock and Dam (NSBLD)in 1937 further restricted spawning migrations in many years to below river mile 265, with the exception of high flow periods during the spawning season in some years.During the late 1950's through the early 1960's, the Corps'Savannah River navigation project constructed 38 cuts across meander bends that shortened the river by 78 miles.Therefore, the NSBLD is now located at river mile 187.3.The Stevens Creek Dam, a South Carolina Electric and Gas hydroelectric project, was constructed upstream of the Augusta Diversion Dam in 1914, blocking all diadromous fish migrations at that point.Although greatly reduced from former abundance, diadromous fish are an important and increasing component of the River's sport and commercial fisheries.

American shad, blueback herring, and lesser numbers of striped bass and sturgeon migrate to the NSBLD facility which is theTrrst major obstrUction to passage on the river.However, some fish have contfuued tomigrate to historical spawning grounds above the facility when flow conditions are suitable.The fish pass upstream by swimming through fully opened dam gates at flows of 16,000 cfs or higher, and by swimming through the navigation lock when it is operated in a manner suitable for fish passage.Presently the lower Savannah River provides extremely important striped bass habitat.Although the majority of historical upstream spawning habitat for striped bass has been inundated by major reservoirs, some remaining rocky rapids habitat exists in the Augusta Shoals from just below NSBLD up to Stevens Creek Dam.After construction of mainstem dams and prior to initiation of a tide gate operation in 1977, the primary spawning area for striped bass in the Savannah River system was the tidal fresh water zone approximately 18-25 miles from the river mouth, specifically the Little Back River (McBay 1968;Rees 1974).Salinity changes due to the tide gate operation (1977-1992) reduced the extent of this tidal freshwater zone.Studies indicated significant declines in numbers of striped bass eggs and larvae in the lower Savannah River system during this period.These declineswererelated to increased salinity and modified transport patterns caused by the tide gate and associated hydrologic modifications (VanDen Avyle et aL 1990, Winger and Lasier 1990).The Little Back River, adjacent to the lower Savannah River, had unique physical characteristics that made it the primary source in the Savannah River System for efficient collection of brood fish for the Georgia statewide propagation and stocking program of striped bass and hybrid bass (white bass x striped bass).It has not served in that capacity since the 1980's.The GADNR adopted a striped bass harvest moratorium in 1988.In the early 1980's, an average of 4,291 kilograms of striped bass were harvested annually by sport fishermen in the Savannah River downstream of the NSBLD (Schmitt and Hornsby 1985).14 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 The Corps of Engineers, Georgia Department of Natural Resources, South Carolina Department of Natural Resources, US Fish and Wildlife Service,andthe National Oceanic and Atmospheric Administration Fisheries Service are actively coordinating with private sector partners to address enhancement and restoration of diadromous fisheries, wetlands, and other aquatic resources in the Savannah River.2.9.2.Wetlands Palustrine forested wetlands dominate the extensive alluvial plain of the Savannah River.The wettest parts of the flood plain, such as swales, sloughs, and back swamps are dominated by bald cypress, water tupelo, and swamp tupelo.Slightly higher areas, which are usually flooded for much of the growing season are often dominated by overcup oak and water hickory.Most ofthe Savannah River floodplain consists of low relief flats or terraces.These areas are flooded during most of the winter and early spring and oneortwo months during the growing season.Laurel oak is the dominant species on these flats and green ash, American elm, sweetgum, spruce pine, sugarberry, and swamp palm are often present.Swamp chestnut oak, cherrybark oak, spruce pine, and loblolly pine are found on the highest elevations of the flood plain, which are only flooded infrequently during the growing season.On the Savannah River downstream of Interstate Highway 95 tidal palustrine emergent wetlands, also known as tidal freshwater prevalent.

_Tidai palustrine-emergent wetlandsare flooded twice daily by tidal action in the study area.These marshes are vegetated with a diverse mixture of plants including giant cutgrass, spikerushes, and up to 58 other plant species (pearlstine et al.1990, Applied Technology and Management 1998).In palustrine emergent wetlands, primary productivity is high, falling in the range of 500 to 2000 grams/square meter/year (Odum et al.1984).The quality of primary production is also high.Major primary producers in the salt marsh community are grasses that have little immediate nutritional value to fish and wildlife but support an important detritus based food web (Teal 1962).In contrast, the fleshy broad-leaf plants characteristic of fresh marshes generally are high in nitrogen and low in fiber content and there is a high incidence of direct grazing or feeding on these plants (Odum et al.1984).Fresh marsh vegetation also contributes to the food web base that supports the study area's freshwater fishery.The leaves of the larger macrophytes in this community are used as attachment places by mollusks, insect nymphs, rotifers, hydra, and midge larvae.These are all important fish foods.The submerged littoral zone is vital to the development of freshwater fish, as well as some marine and estuarine species, as these areas are the principal spawningsitesand provide nursery and juvenile habitats.2.9.3.Wildlife Wildlife associated with forested wetlands is numerous and diverse.The furbearers are an important component of these wetlands andincludebeaver, muskrat, mirIk, otter, bobcat, gray fox, raccoon, and opossum.Deer, turkey, and even black bear in the more isolated areas, use the bottomlands.

Palustrine emergent wetlands also provide excellent habitat for furbearers including the mirIk, beaver, and river otter.Terrestrial species from surrounding areas often 15 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 utilize the fresh marsh edge for shelter, food, and water.These include raccoon, opossum, rabbit, and bobcat.The study area is part of the Atlantic Flyway and forested wetlands provide important wintering habitat for many waterfowl species and nesting habitat for wood ducks.Many species of woodpeckers, hawks, and owls use the bottomlands and swamps.Wood stork Little blue heron Palustrine emergent wetlands also provide habitat for many bird species.Resident, transient, and migrating birds of both terrestrial arid aquatic origm utilize food and shelter foundthis community.

Some species use freshwater marshes for nesting and breeding.Waterfowl feed upon fresh marsh vegetation, mollusks, insects, small crustaceans, and fish found in the fresh marsh community.

Wading birds such as the wood stork, great blue heron, little blue heron, green heron, snowy egret, and great egret also heavily utilize the tidal freshwater marsh.The study area provides excellent habitat for a large number of reptiles and amphibians.

Wetland habitats support many kinds of frogs including the bullfrog, bronze frog, southern leopard frog, several species of tree frogs, cricket frogs, and chorus frogs.Turtles found in the wetlands include the river cooter, Florida cooter, pond slider, eastern chicken turtle, snapping turtle, mud turtle, and stinkpot.Snakes found in the wetlands include the red-bellied water snake, banded water snake, brown water snake, eastern mud snake, rainbow snake, and eastern cottonmouth.

The American alligator can be observed on streams and ponds ofthe Coastal Plain study area.Neotropical migratory birds, many of which are decreasing in abundance, depend upon contiguous tracts of forested swamps for breeding and as corridors during migration.

Robbins et al.(1989)found that the most area-sensitive bird species required at least 2,800 acres of contiguous forest to be present.The extensive forested wetlands of the Savannah River flood plain provide very valuable habitat for these birds.The American swallow-tailed kite, a state (South Carolina)listed endangered species, can be observed on the study area.Swallow-tailed kites nest in and are closely associated with palustrine wetlands.Wetland Habitat 16 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 2.9.4.Endangered Species Federal Endangered (E), Threatened (T), and Candidate (C)species that are likely to occur in the Savannah River Basin Study Area are listed in Table 3: Table 3: Endangered Species List SPECIES SCIENTIFIC NAME STATUS MAMMALS.Indiana Bat Myotis sodalis E West Indian manatee Trichechus manatus E BlR])S..*.......Bald eagle Haliaeetus leucocevhalus T Red cockaded woodpecker Picoides borealis E Piping plover Charadrius melodus T Wood stork Mycteria americana E Kirtland's warbler Dendroica kirtlandii)

E REPTILES..Eastern indigo snake Drymarchon corais couperi T AMPHIBIANS Flatwoods salamander Ambystoma cinJ!:Ulatum T..FiSh--'-.-Shortnose sturgeon Acipenser brevirostrum E PLANTS Canby's dropwort Oxvpolis canbvi E Chaff seed Schwalbea americana E Schweinitz's sunflower Helianthus schweinitzii E Small whorled pogonia Isotria medeoloides T Pondberry Lindera melissifolia E Rough leaved loosestrife Lvsimachia asverulaefolia E False Poison Sumac Rhus michauxii E Bunched arrowhead Sagittaria fasciculata E White irisette Sisyrinchium dichotomum E Dwarf flowered heartleaf Hexastylis naniflora T Mountain sweet pitcher plant Sarracenia rubra ssp.jonesii E Harperella Ptilimnium nodosum E Swamp pink Helonias bullata T Smooth coneflower Echinacea laevif?ata E Seabeach amaranth Amaranthus pumilus T Persistent trillium Trillium versistens E Relict trillium Trillium reliC/uum E Little amphianthus Amphianthus pusillus T Miccosukee gooseberry Ribes echinellum T Bog asphodel Narthecium americanum C The tidal fresh marsh at the Savannah National Wildlife Refuge (NWR)supports an extremely diverse plant community providing food, cover and nesting habitat for a wide variety of wildlife species.Tidal freshwater marsh is relatively scarce in comparison to coastal brackish and salt marshes.Past harbor modifications, including harbor deepening, have greatly increased salinity levels throughout much of the Savannah NWR and reduced the quantity of tidal freshwater 17 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 marsh.According to our preliminary evaluation, the Savannah NWR contained about 6,000 acres of tidal freshwater marsh when it was established in 1927.By 1997, due to the cumulative impacts of harbor deepening, tidal freshwater marsh had declined to 2,800 acres, a reduction of 53 percent.Prior to 1977, the Savannah River supported the most important naturally reproducing striped bass population in the State of Georgia, but production of striped bass eggs in the Savannah River estuary declined by about 95 percent.Tide gate operation, in conjunction with the cumulative impacts of harbor deepening, caused a number of impacts.These included increases in salinity and loss of suitable spawning habitat throughout most of Little Back Riverandthe lower Savannah River.Striped bass eggs and larvae were also transported through New Cut and then rapidly downstream to areas with toxic salinity levels.It was hoped that the tide gate restoration project would improve most of these conditions.

Annual stocking efforts by the GADNR have been very successful in increasing the number of striped bass ill the lower Savannah River, and current population levels approach historic levels.After a 17-year closure, the striped bass fishery wasonceagain opened in October 2005.

3.0 DESCRIPTION

OF THE PROPOSED ACTION AND OTHER ALTERNATIVES 3.1.ALTERNATIVE FORMULATION The objective of the alternative formulation process was to make changes to the existing SRBDCP that focused on conservation of water resources during severe droughts.Alevel Project Delivery Team (PDT)and an Interagency PDT were initially formed to develop a basic set of alternatives for consideration.

Stakeholder meetings, consisting of various user groups, were held to refme and expand on the study alternatives.

Subsequent meetings were held to review model output, allowing comparison between the proposed alternatives and the NAA.3.2.ALTERNATIVES ANALYSIS Alternatives were developed for consideration as part of the planning process and are: a.NAA (Continue with the SRBDCP, March 1989)b.Alternative 1 c.Alternative 2 d.Alternative 3 e.Alternatives Considered But Eliminated From Detailed Consideration 3.2.1.No Action Alternative This Alternative consists of the Corps taking no action to modify its existing SRBDCP.The operating procedures described in that 1989 Plan would continue to be implemented and forms the basis upon which comparisons to the other alternatives can be made.18 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Action thresholds were established in the SRBDCP and are based on pool elevations at Hartwell and Thunnond Lakes.Russell Lake has a relatively small conservation pool, therefore it does not have action thresholds delineated.

Due to the nature of pumped storage operation Russell Lake stays near guide curve during drought operations.

Thresholds at Hartwell and Thunnond Lakes are shown in Table 4 and Table 5 and Figures 1 and 2.Using this plan, the lakes reached Level 2 in September 1999 and Level 3 in September 2002.In October 2002, J.Strom Thunnond Lake was more than 13 feet below its normal operating pool.Table 4: Hartwell Action Levels for the NAA LEVEL*18APR-15 OCT 1 DEC-1 JAN**ACTION (ft-msl)(ft-msl)1 656 655 Public safety information 2 654 652 Reduce Thurmond discharge to 4500 cfs, reduce Hartwell discharge as appropriate to maintain balanced pools.3 646 646 Reduce Thurmond discharge to 3600 cfs, reduce Hartwell discharge as appropriate to maintain balanced pools.4 625 625 Outflow=Inflow..'c'.-.'---'..c*--Top of Conservation Pool Le-ve11 655-656 Levet:2 652-654 Level4 Bottom of Conservation Pool'660 659 656 654 652-1.---650 648 646-+...: L::;.:0Ye=1;.::3:...-

_644 5642 ,i63S 11I636 634 632 630 628 626 624 622 620 Figure 1: Hartwell Action Levels for the NAA*Level as shown in Figure 1**Lake elevationsforthe periods January 1 to April 18 and October 15 to December 1 are linearly interpolated from this data as shown in Figure 1 19 DraftEA Drought Contingency Plan Update Savannah River Basin Table 5: Thurmond Action Levels for the NAA May 2006 LEVEL*1 MAY-15 OCT 15 DEC-1 JAN**ACTION (ft-msl)(ft-msl)1 326 325 Public safety infonnation 2 324 322 Reduce Thunnond discharge to 4500 cfs.3 316 316 Reduce Thunnond discharge to 3600 cfs.4 312 312 Outflow=Inflow 330 328 326 324-;;;E 322 e.-c.!i!320 oS!w 318 316 314 312 To of Conservation Pool Level 1 325*326 Level 2 322*324 Level 3 Level 4 Bottom of Conservation Pool 310 JlIn fllb MiIr Apr May Jun.lui Aug Sop Od"011 Doll Jan Figure 2: Thurmond Action Level for the NAA As described in the Drought Contingency Plan, the Corps would also monitor salinity levels in the estuary.During"critical water periods" Savannah District would perform roving salinity sampling at several locations in the estuary to determine and document the extent of salinity intrusion.

The Savannah Basin projects have never reached Level 4 in the 16 years that the Plan has been operational.

F our pumped storage units are available at RBR June 1 st through September 30 th for each alternative.

Eighty unit hours of pumping per week is the amount that is required to support the current hydropower contract.Pumping beyond 80 unit hours up to the maximum allowed by the Richard B.Russell Dam and Lake Project Pumped Storage Environmental Assessment of August 1999 can still occur when economically feasible.*Level as shown in Figure 2..Lake elevations for the periods JanuaryIt May I and October 15 to December 15 are linearly interpolated from this data as shown in Figure 2 20 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 This alternative is considered in detail and will be evaluated in regard to all environmental concerns.3.2.2.Alternative 1 Alternative 1 consists of retaining major components of the 1989 SRBDCP and adding several other features.The discharge restrictions at Thurmond were allowed to transition back to higher flows prior to reaching full pool.A two-foot buffer was used to simulate engineering judgment to distinguish a lasting drought recovery from a temporary increase in inflows.The minimum daily average release at Thurmond was adjusted from 3600 cfs to 3800 cfs, and a maximum daily average release of3800 cfs was specified in drought leve13.Drawdown dates at Hartwell and Thurmond Lakes would also be synchronized as listed in Table 6.Action thresholds are shown in Figure 3 and Figure 4.Table 6: Hartwell and Thurmond Action Levels for Alternative 1 LEVEL 1 APR-15 OCT 15DEC-IJAN ACTION (ft-msl)(ft-msl)-t 1 656 andJ26__-,-

324 Public safety infonn.ation I 2 654 and 324 652 and 322 Reduce Thurmond discharge to 4500 cfs.3 646 and 316 646 and 316 Reduce Thurmond discharge to 3800 cfs.4 625 and 312 625 and 312 Outflow=Inflow 665 660 655 650 635 630 625 Top of Conservation Pool (656-660)Level 1 (654-656)Level 2 (652-654)--:---Level 3 (546)Level 4 (625-Bottom of the Conservation Pool)620 c: m;l Figure 3: Hartwell Action Levels for Alternatives 1, 2 and 3 21 Level 2 322-324 DraftEA Drought Contingency Plan Update Savannah River Basin 335,-------------------------------, Top of Conservation Pool (326-330)330 Level 1 (324-326)=-325 III!c o!iii 320-1----------------------------_1 Level 3 (316)315-1----------------------------_1 Level 4 (312-Botlom oflhe Conservation Pool)ac:;10:l;!:z:z Figure 4: Thurmond Action Levels for Alternatives 1, 2 and 3 May 2006 3.2.3.Alternative 2 Alternative 2 includes all components of Alternative 1.Additionally, the maximum weekly average discharge at 1.Strom Thurmond would be 4200 cfs and 4000 cfs for drought levels 1 and 2, respectively.

Table 7: Hartwell and Thurmond Action Levels for Alternative 2 OCT 15DEC-IJAN ACTION (ft-msl)(ft-msl)1 656 and 326 654 and 324 Reduce Thurmond discharge to 4200 cfs.2 654 and 324 652 and 322 Reduce Thurmond discharge to 4000 cfs.3 646 and 316 646 and 316 Reduce Thurmond discharge to 3800 cfs.4 625 and 312 625 and 312 Outflow=Inflow 3.2.4.Alternative 3 Alternative 3 includes all components of Alternative 2, but the daily average release at Thurmond for Level 3 would be 3600 cfs.22 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 3.2.5.Alternatives Considered But Eliminated From Detailed Consideration Several Project Delivery Team meetings and Stakeholder meetings were held in late 2004 through the Spring of2005 with possible alternatives discussed.

At the 4 March 2005 Stakeholders meeting in Evans, Ga.the alternatives were prioritized by the stakeholders in a rating process allowing some alternatives to be eliminated from further consideration.

Alternatives eliminated included: increasing the flows when return elevations hit one foot above the elevation triggers, increasing the number of drought triggers for drought management and return from a drought to provide a more gradual transition to 3600 cfs, lowering the minimumdroughttrigger 3 releases to 3300 or 3000 cfs with 3600 cfs being maintained at the New Savannah Bluff Lock and Dam, adjusting Level 3 elevations at Hartwell from 646 to 648 or 649 and adjusting Level 3 elevations at JST from 316 to 318 or 319.3.2.6.Selected Alternative The Proposed Action is 2.It consists of retaining the major components of the 1989 SRBDCP and adding several other features.The discharge restrictions at Thurmond would be allowed to transition back to higher flows prior to reaching full pool.A two foot buffer would be used to simulate engineering judgment to distinguish a lasting drought recovery from a temporary increase in inflows.The minimum daily average release at Thurmond would be adjusted.from 3600 cfs.tol800 cfs, and a specified daily average release of3800 cfs:w:ould be included in drought level 3.Additionally, the maximum weekly average discharge at J.Strom Thurmond would be 4200 cfs and 4000 cfs for drought levels 1 and 2, respectively.ResSim pool plots are included in Appendix F.4.0 ENVIRONMENTAL AND SOCIOECONOMIC CONSEQUENCES Savannah District does not anticipate any substantial effects to air quality, noise, non-renewable resources, mineral resources, farmland, or to fish.We do not envision any irretrievable commitments of resources from either alternative.

Savannah District believes the proposed project is consistentwiththe Coastal Zone Management Program to the maximum extent practicable.

Alternatives 1,2 and 3 were each compared to the NAA in this section.For Sections 4.1 thru 4.6, this was conducted primarily by comparing Downstream Hydrographs (example can be found on page 24), comparing Pool Elevation Tables (example can be found on Pages 28)and by employing the Ecosystems Function Model (EFM), in conjunction with information from the 1-3 April, 2003, Scientific Stakeholders Workshop.An example of the EFM can be found on pages 30-31.4.1.WATER QUALITY When discharges are reduced from Thurmond Dam, impacts occur to downstream water quality.Reduced discharges result in increases in water temperature and a reduction in the quality of the river downstream of point source discharges.

Increasing the low flows that are associated with drought conditions would enhance water quality.The summer months are the most critical to aquatic resources, so reduced flow rates during those months wouldcausegreater adverse impacts.23 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 The State of South Carolina uses a minimum flow of 3600 cfs at the Augusta gage for the permitting of point source discharges on the River, while the State of Georgia uses the 7Q10 flow values of 3800 cfs at the Augusta gage, 4160 cfs at the Mi1lhaven gage and 4710 cfs at the Clyo gage.In the following analysis, however, the flows of the modeled alternatives were not compared to these values.They were compared to the flows of the modeled NAA to determine the impacts of changing the existing SRBDCP.Downstream hydrographs that were generated by ResSim modeling were used here and in other portions of Section 4.0 to compare Alternatives 1,2 or 3 to the NAA.The following example is a two year portion of the overall hydro graph that covers approximately five years.It compares Alternative 1 to the NAA and shows a modeled 200 cfs increase in predominant flows for Alternative 1.Predominant flows are those that are present for much of the drought of record on a modeled alternatives downstream hydrograph.

As mention earlier, flow increases during drought enhance water quality.Similar comparisons follow in this Water Quality section.IIAUGUSTNFLOWI01JAN199711 DAYIALT1-01

'*10000 9000 8000 7000'""6000 Ll'-/0 i:L 5000 4000 3000 2000 I..I..-I-I-.I 1-----'I 1-1Ii,

-IIUJ\...*kt..'-"Cj\\'-I I I I I Jan 2000 I Apr Jul 2001 Oct.Jan I Apr Jul 2002 Oct Jan I 2003-AUGUSTAALT1-0 FLOW-AUGUSTA BASE_DCP-O FLOW Figure 5: Example of Downstream Hydrographs 24 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of the NAA May 2006 The NAA would have no adverse impacts on water quality, as the existing SRBDCP of March 1989 with coordinated additions would continue to be used.Effects of Alternative 1 Augusta Gage This alternative would have a minor positive impact on water quality in the Augusta area.The downstream hydrograph of this alternative provides flows that are primarily above 3800 cfs at the Augusta gage, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200 cfs increase in predominant flows is spread across the calendar years, so overall water quality would be enhanced.Millhaven Gage This alternative would have a minor positive impact on water quality in the Millhaven area.The downstream hydro graph of this alternative and the NAA provides flows that greatly exceed 6000 cfs from September 1997 t6 Jurie-19"98.

The flows of this and"the NA.A vary little'betWeen" June 1998 and November 2000 and are 50-900 cfs higher than the NAA between December 2000 and September 2003.The 50-900 cfs increase in flows for the long period from December 2000 to September 2003 would enhance overall water quality.ClyoGage This alternative would have a minor positive impact on water quality in the Clyo area.The downstream hydro graph of this alternative and the NAA provide flows that greatly exceed 6000 cfs from September 1997 to September 1998.From October 1998 to November 2000 there is little variation between the flows of this alternativeandthe NAA and from December 2000 to December 2002 this alternatives flows are 200-1000 cfs higher.The flows again greatly exceed 6000 cfs from January 2003 to August 2003 for this and the NAA.The 200-1000 cfs increase in flows for the long period from December 2000 to December 2002 would enhance overall water quality.Effects of Alternative 2 Augusta Gage This alternative would have a minor positive impact on water quality in the Augusta area.The downstream hydro graph of this alternative provides flows that are primarily above 4000 cfs with occasional drops to 3800 cfs at the Augusta gage, while the NAA provides flows primarily above 3600 cfs.Theseflqw trends occurred between 23 September 1997 and 30 September 2003.The 200-400 cfs increase in predominant flows is spread across the calendar years, so overall water quality would be enhanced.25 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Millhaven Gage This alternative would have a minor positive impact on water quality in the Millhaven area.The downstream hydrograph of this alternative and the NAA provides flows that greatly exceed 6000 cfs from September 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are 50-1000 cfs less than those of the NAA, from March 1999 to August 1999 there is little variation, from September 1999 to October 1999 this alternatives flows are1300 cfs lower, from November 1999 to April 2000 there is again little vaiiation, from May 2000 to June 2000 this alternatives flows are 200-1200 cfs higher, from July 2000 to November 2000 the flows are 50-700 cfs lower and this alternatives flows are 50-400 cfs higher between December 2000 and February 2003.This alternativeandthe NAA provide flows that greatly exceed 6000 cfs from March 2003 to August 2003.The 50-400 cfs increase in flows for the long period from December 2000 to February 2003 would enhance overall water quality.Clyo Gage This alternative would have a minor positive impact on water quality in the Clyo area.The downstream hydro graph of this alternative and the NAA provide flows that greatly exceed 6000 cfs from December 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are 200-1500 cfs less than those ofthe NAA, from March 1999 to July 1999 there is little variation, from August 1999 to October 1999 this alternatives flows are 50-1500 cfs lower,'from Novembef 1999 To April 2000 there is**agam little variation,*

from May2000to Jline*2000 this alternatives flows are 200-4000 cfs higher, from July 2000 to November 2000 the flows are 300-500 cfs less and from December 2000 to February 2003 this alternatives flows are 50-500 cfs higher.The flows again greatly exceed 6000 cfs from March 2003 to August 2003 for thisandthe NAA.The 50-500 cfs increase in flows for the long period from December 2000 to February 2003 would enhance overall water quality.Effects of Alternative 3 Augusta Gage This alternative would have a minor positive impact on water quality in the Augusta area.The downstream hydro graph of this alternative provides flows that are primarily above 4000 cfs with occasional drops to 3800 cfs at the Augusta gage, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September The 200-400 cfs increase in predominant flows is spread across the calendar years, so overall water quality would be enhanced.Millhaven Gage This alternative would have a minor positive impact on water quality in the Millhaven area.For October 1997 there is little variation between this alternative's flows and those of the NAA.The hydrographs of both alternatives provide flows that greatly exceed 6000 cfs from November 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are1000 cfs less than those of the NAA, from March 1999 to August 1999 there is little variation, from September 1999 to October 1999 this alternatives flows are 300-1300 cfs lower, from November 1999 to April 2000 there is again little variation, from May 2000 to June 2000 this alternatives flows are 200-1200 cfs higher, from July2000to December 2000 the flows are700 cfs lower and this alternatives flows are 50-400 cfs higher between January 2001 and 26 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Largemouth bass February 2003.This alternativeandthe NAA provide flows that greatly exceed 6000 cfs from March 2003 to August 2003.The 50-400 cfs increase in flows for the long period from January 2001 to February 2003 would enhance overall water quality.Clyo Gage This alternative would have a minor positive impact on water quality in the Clyo area.For October 1997 there is little variation between this alternative's flows and those of the NAA.The hydrographs of both alternatives provide flows that greatly exceed 6000 cfs from November 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are predominantly 200-1500 cfs less than those ofthe NAA, from March 1999 to August 1999 there is little variation, from September 1999 to October 1999 this alternatives flows are 50-1500 cfs lower, from November 1999 to March 2000 there is again little variation, from April2000to June 2000 this alternatives flows are 200-4000 cfs higher, from July 2000 to November 2000 the flows are 300-500 cfs less and from December2000to January 2003 this alternatives flows are 50-500 cfs higher.The flows again greatly exceed 6000 cfs from February 2003 to August 2003 for thisandthe NAA.The 50-500 cfs increase in flows for the long period from December 2000 to January 2003 would enhance overall water quality.4.2.BIOTIC COMMUNITIES-LAKES

.State-rtatural resourceagencieshave identified largemouth*

bassspawningat the three Corps Savannah River lakes as being a priority in water management decisions.

The spawning period is defmed as beginning when water temperatures reach 65 degrees Fahrenheit and lasts until three weeks after water temperatures reach 70 degrees.The water temperatures are taken each day throughout this period in a sunny cove between 1000 and 1630 hours0.0189 days <br />0.453 hours <br />0.0027 weeks <br />6.20215e-4 months <br /> by submersing a thermometer six inches where the water is approximately three to five feet deep.The spawning period usually starts around the first of April and lasts 4 to 6 weeks.The 4 week period of April 1-28 was used in the HEC-ResSim model applications.

Stable lake levels should be provided during this peak spawning period to prevent the stranding of eggs and abandonment of nests.Throughout the spawning season, water levels should not be lowered more than six inches below the highest lake elevation recorded during the operational spawning window.If inflows during the spawning season cause lake levels to rise to flood levels, managers have the authority to lower lake levels more than 6 inches, since flood control takes precedence over fish spawn.Maintaining these stable lake levels may not be possible during drought.Pool Elevation Tables that were generated by HEC-ResSim model were used in this Section to compare Alternatives 1,2 or 3 to the NAA.The following example reveals that the modeled pool elevations show a 0.64-foot maximum drop that would occur from 12 April to 17 April 1998 for Hartwell Lake.The paragraph following the example table contains this occurrence of 0.64 feet that exceeds six inches.There are seventy-two tables that were used similarly in this Biotic Communities-Lakes section.It should be noted that this model does not operate the lakesandthe existing manual lake operation is more adaptive in maintaining the stable spawning pools.27 DraftEA Drought Contingency Plan Update Savannah River Basin 191 01Ar 98 24:00 659.34 192 02Ar 98 24:00 659.38 193 03Ar 98 24:00 659.41 194 04A r98 24:00 659.45 195 05Ar 98 24:00 659.64 196 06Ar 98 24:00 659.79 197 07Ar 98 24:00 659.73 198 08Ar 98 24:00 659.66 199 09Ar 98 24:00 659.96 200 10Ar 98 24:00 660.32 201 11Ar 98 24:00 660.47 202 12 A r 98 24:00 660.63 203 13Ar 98 24:00 660.5 204 14Ar 98 24:00 660.36 205 15Ar 98 24:00 660.24 206 16Ar 98 24:00 660.05 207 17Ar 98 24:00 659.99 208 18Ar 98 24:00 660.4 209 19Ar 98 24:00 660.66 210 20A r 98 24:00 660.81 211 21A r 98 24:00 660.91 212 22Ar 98 24:00 660.98 213 23Ar 98 24:00 661.03 214 24Ar 98 24:00 661.14 215 25Ar 98 24:00 661.29 216 26Ar 98 24:00 661.3 217 27Ar 98 24:00 661.06 218 28Ar 98 24:00 660.82 Figure 6: Example of Pool Elevation Tables May 2006 Effects of the NAA (By observing the Pool Elevation tables)Hartwell Lake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be 0.64,0.26,0.22,0.29,0.23 and 0.28 feet.RBRLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be0.67,0.01, 0.07, 1.07,0.01 and 0.01 feet.JSTLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be 0.41,0.14,0.16,0.32,0.13 and 0.28 feet.Review of the above model-generated pool elevation reductions show that the 6-inch maximum lowering for April 1-28 would be exceeded 1 year at Hartwell Lake, 2 years at RBR Lake and 0 28 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 years at JST Lake during the 6-year period of analysis.The approved SRBDCP has been found to be an acceptable plan based on its impacts on biotic communities in the lakes.Effects of Alternative 1 (By observing the Pool Elevation tables)Hartwell Lake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respective1ybe 2.13,0.26,0.25,0.37,0.25 and 0.02 feet.RBRLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively0.01,0.01,0.82,0.01,0.07 and 0.01 feet.JSTLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be0.42,0.14, 0.18, 0.34, 0.17 and 0.13 feet.Review of the above model-generated pool elevation reductions shows that the 6-inch maximum lowering for April 1-28 would be exceeded 1 year at Hartwell Lake, 1 year at RBR Lake and 0 yeats atJST Lake during the'6':year1Jeriod of aria lySis.This alternativewolildhave nef adverSe-.impact, as 2 total exceedances were observed and 3 were observed previously for the NAA.The exceedances do not primarily occur at one lake.Effects of Alternative 2 (By observing the Pool Elevation tables)Hartwell Lake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be 2.13,0.26,0.15,0.56,0.27 and 0.49 feet.RBRLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be0.01,0.01,0.66, 0.62, 0.01 and 0.40 feet.JSTLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be 0.42,0.14,0.90,0.27,0.15 and 0.20 feet.Review of the above model-generated pool elevation reductions shows that the 6-inch maximum lowering for April 1-28 would be exceeded 2 years at Hartwell Lake, 2 years at RBR Lake and 1 year at JST Lake during the 6-year period of analysis.This alternative would have a minor adverse impact, as 5 total exceedances were observed and 3 were observed for the NAA.The exceedances do not primarily occur at one lake.29 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of Alternative 3 (By observing the Pool Elevation tables)May 2006 Spider lily (Hymenocalis coronaria)

Hartwell Lake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be 2.13,0.26,0.15,0.56,0.27 and 0.45 feet.RBRLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively be 0.01,0.01,0.66, 0.62, 0.01 and 0.19 feet.JSTLake The maximum lowering of the pool elevations between April 1-28 for the drought of record years 1998 to 2003 would respectively'be0.42,0.14,0.90, 0.27, 0.15 and 0.26 feet.Review of the above model-generated pool elevation reductions shows that the 6-inch maximum lowering for April 1-28 would be exceeded 2 years at Hartwell Lake, 2 years at RBR Lake and 1 year at JST Lake during the 6-year period of analysis.This alternative would have a minor adverse impact, as 5 total exceedances were observed and 3 were observed for the NAA.The exceedances do not primarily occur at one lake.4.3.BIOTIC COMMUNITIES-SHOALS The fmal report from the Scientific Stakeholders Workshop of 1-3 April 2003 listed shad, robust redhorse, Atlantic sturgeon, the shoals spider lily (Hymenocalis coronaria) and juvenile out-migration as being high priorities for the Shoals during dry years.The Shoals are defmed as the 7.2 kilometer stream segment that is upstream of Augusta and downstream of the Augusta Canal Diversion Dam.The high priority fish species would benefit from higher flows across the shoals from January to May that would provide seasonal spawning and passage.The endangered shoals spider lily would benefit from higher flows from June to December that would provide protection from deer grazing.Undefmed very high flows could be detrimental to the spider lily, but these are not expected during times of drought and are not considered here.Higher flows in November and December would also enhance out-migration of juvenile fish.Effects of the NAA Selection of the NAA and continuing with the existing SRBDCP with coordinated additions would have acceptable impacts on these biotic communities.

30 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of Alternative 1 (By comparing the alternatives Augusta gage Downstream Hydrograph to that of the NAA)May 2006 This alternative would have a minor positive impact on these biotic communities.

As discussed earlier in the Water Quality section, this alternative provides flows that are primarily above 3800 cfs at the Augusta gage, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200 cfs increase in predominant flows is spread across the January to May, June to December and November to December time frames, so seasonal fish spawning, fish passage, shoals spider lily protection from deer grazing and juvenile out-migration would be enhanced.Effects of Alternative 1 (By employing the Ecosystems Function Model (EFM)in conjunction with Augusta Shoals information from the 1-3 April 2003 Scientific Stakeholders Workshop)The EFM (established by the US Army Corps of Engineers Hydrologic Engineering Center (HEC>>was used to compare Alternatives 1,2 and 3 to the NAA.Recommendations from the 2003 Scientific Stakeholders Workshop, including seasonal and eco-health curve data, were used to establish flow/habitat relationships (see Example 1 below)for several resources in the EFM.HEC-ResSim files were'loaded irito the model and are shown listed in Example 2beIow.Output from the model consists of the average flow for each alternative in the specified season and whether a positive or negative impact would result for the particular resource when the flow in the alternatives is compared to the flow in the NAA (see Example 3).Example 1 31 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Example 2 Example 3 EvaluatEd at: 11/03/2005 08:36--i""-Po, 3846,9 3.847 r,co 3907.2 3,907 Fos'3907.5 3641.5: I Summary i Augusta Base Augusta

....,._.,----."--,.._---_,._"*.."".!

i Ch Stage, Flow, Ch ft,cfs'g.ft cfs g.Relationship Low IFlow,;-Sase-HaIJltat ,for Shad and Striped Bass Four flow/habitat relationships were analyzed for the shoals area.Habitat for Shad and Striped Bass (7500 cfs recommended in the workshop):

The output for this model run was 3847 cfs.This is greater than the output of 3642 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.Shoals Spider Lily in June and July (6200 cfs recommended in the workshop):

The output for this model run was 3800 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.Shoals Spider Lily from August to October (5500 cfs recommended in the workshop):

The output for this model run was 3800 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.Shoals Spider Lily in November and December (6200 cfs recommended in the workshop):

The output for this model run was 3800 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative I would produce a minor positive impact on the resource.32 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of Alternative 2 (By comparing the alternatives Augusta gage Downstream Hydrograph to that of the NAA)May 2006 This alternative would have a minor positive impact on these biotic communities.

As discussed earlier, this alternative provides flows that are primarily above 4000 cfs with occasional drops to 3800 cfs at the Augusta gage, the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200-400 cfs increase in predominant minimums is spread across the January to May, June to December and November to December time frames, so seasonal fish spawning, fish passage, shoals spider lily protection from deer grazing and juvenile out-migration would be enhanced.Effects of Alternative 2 (By employing the EFM in conjunction with Augusta Shoals information from the 1-3 April 2003 Scientific Stakeholders Workshop)Four flow/habitat relationships were analyzed for the shoals area.Habitat for Shad and Striped Bass (7500 cfs recommended in the workshop):output fOJ: this model run was 3907 cfs.J:hisjs greater than the outpu(of 3647 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.Shoals Spider Lily in June and July (6200 cfs recommended in the workshop):

The output for this model run was 3856 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.Shoals Spider Lily from August to October (5500 cfs recommended in the workshop):

The output for this model run was 3800 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.Shoals Spider Lily in November and December (6200 cfs recommended in the workshop):

The output for this model run was 4000 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 2 would.produce a minor positive impact.on the resource.Effects of Alternative 3 (By comparing the alternatives Augusta gage Downstream Hydrograph to that of the NAA)This alternative would have a minor positive impact on these biotic communities.

As discussed earlier, this alternative provides flows that are primarily above 4000 cfs with occasional drops to 3800 cfs at the Augusta gage, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200-400 cfs increase in predominant minimums is spread across the January to May, June to December and November to December time frames, so seasonal fish spawning, fish passage, shoals spider lily protection from deer grazing and juvenile out-migration would be enhanced.33 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of Alternative 3 (By employing the EFM in conjunction with Augusta Shoals information from the 1-3 April 2003 Scientific Stakeholders Workshop)Four flow/habitat relationships were analyzed for the shoals area.May 2006 Habitat for Shad and Striped Bass (7500 cfs recommended in the workshop):

The output for this model run was 3907 cfs.This is greater than the output of 3642 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.Shoals Spider Lily in June and July (6200 cfs recommended in the workshop):

The output for this model run was 3856 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.ShoalsSptder Lily from August to October (5500 cfs recommended in the The output for this model run was 3600 cfs.This is the same as the output of the NAA model run, so Alternative 3 would produce no impact on the resource.Shoals Spider Lily in November and December (6200 cfs recommended in the workshop):

The DUtput for this.model run.was 4000, cfs..This is greater than.the output.of 3600_c.fs for the--.'....NAA model run, so Alternative 3 would produce a minor positive impact on the resource.4.4.BIOTIC COMMUNITIES-FLOODPLAIN The floodplain reach is defmed as beginning downstream of the Augusta shoals and extending to Ebenezer Landing (approximate river kilometer 65).The report from the April 1-3, 2003 workshop listed seedling establishment as being the high priority for the floodplain reach during dry years.The establishment of seedlings is promoted by low flows (3000 cfs or less was recommended in the workshop to occur every 10 to 20 years and not last longer than 3 years)between April and October for 3 consecutive years.However, flows up to 10,000 cfs are expected to remain within the stream charmel and are not expected to affect the floodplain.

The 2003 workshop recommendations and the 10,000 cfs stream channel capacity are considered below.Graphical and tabular information is available for April to October for the years2002.Effects of the NAA Selection of the NAA and continuing with the existing SRBDCP with coordinated additions would have no adverse impact on this biotic community.

Effects of Alternative 1 (By comparing the alternatives Millhaven gage Downstream Hydrograph to that of the NAA)For 2003 Workshop recommendations:

Selection ofthis alternative would have a minor adverse impact on this biotic community, but reducing flows to the recommended above would produce adverse impacts for other Savarmah River resources.

Action Level 4, as discussed in Section 2.1.1, would be required to 34 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 produce flows as low as 3000 cfs in the floodplain.

The downstream hydro graph of this alternativeandthe NAA provides flows that greatly exceed 6000 cfs from September 1997 to June 1998.The flows ofthis and the NAA vary little between June 1998 and November 2000 and are 50-900 cfs higher than the NAA between December 2000 and September 2003.The higher flows produced by this alternative are expected to produce a minor adverse impact, because they are increases above the recommended 3000 cfs.It should be noted that achieving flows of 3000 cfs for the desired three separate seasons would likely result in a violation of state water quality standards.

Considering stream channel capacity: The physical characteristics of the Savannah River stream channel limit the floodplain overbank benefit to flows exceeding 15,000 cfs.The modeled flows produced by this alternative rarely exceed bankfull capacity for the period of July 1998 to January 2003, so no adverse impact would result.Additional flood control storage in the reservoir system may be required to eliminate periods when flows exceed channel capacity between April and October during a three year period for seedling establishment during normal to wet years.Effects of Alternative 2 (By comparing the alternatives Millhaven gage Downstream Hydrograph to that of the NAA)For 2003 Workshop Recommendations Selection ofthis alternative would have a minor adverse impact on this biotic community, but reducing flows to the levels recommended above would produce adverse impacts for other Savannah River resources.

Action Level 4, as discussed in Section 2.1.1, would be required to produce flows as low as 3000 cfs in the floodplain.

The downstream hydrograph of this alternative and the NAA provides flows that greatly exceed 6000 cfs from September 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are 50-1000 cfs less than those of the NAA, from March 1999 to August 1999 there is little variation, from September 1999 to October 1999 this alternatives flows are 300-1300 cfs lower, from November 1999 to April 2000 there is again little variation, from May 2000 to June 2000 this alternatives flows are 200-1200 cfs higher, from July 2000 to November 2000 the flows are 50-700 cfs lower and this alternatives flows are 50-400 cfs higher between December 2000 and February 2003.This alternativeandthe NAA provide flows that greatly exceed 6000 cfs from March 2003 to August 2003.The higher flows produced by this alternative are expected to produce a minor adverse impact, because they are increases above the recommended 3000 cfs.It should be noted that achieving flows of 3000 cfs for the desired three separate seasons would likely result in a violation of state water quality standards.

Considering Stream Channel CapacityThephysical*characteristics of the Savannah River stream channel limit the floodplain overbank benefit to flows exceeding 15,000 cfs.The modeled flows produced by this alternative rarely exceed bankfull capacity for the period of July 1998 to January 2003, so no adverse impact would result.Additional flood control storage in the reservoir system may be required to eliminate periods when flows exceed channel capacity between April and October during a three year period for seedling establishment during normal to wet years.35 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of Alternative 3 (By comparing the alternatives Millhaven gage Downstream Hydrograph to that of the NAA)May 2006 For 2003 Workshop Recommendations The Downstream Hydrograph for this alternative is very similar to that of Alternative 2 above, so selection ofthis alternative would also have a minor adverse impact on this biotic community.

Considering Stream Channel Capacity The Downstream Hydrograph for this alternative is very similar to that of Alternative 2 above, so no adverse impact would result.4.5.BIOTIC COMMUNITIES-EsTUARY The report from the April 1-3, 2003 workshop listed freshwater marsh habitat and the salinity gradient as being the high priorities for the estuary reach during dry years.The estuary has been defmed as extending from Ebenezer Landing (approximate river kilometer 65)down to the mouth of the river.Historically, river flows of 4,000 to 5,000 cfs and less at the USGS Clyo gage have resulted in a stressed freshwater marsh plant community and an associated upriver shift of the salinity gradient (higher salinity zones).Higher flows throughout the year would provide a healthier freshwater marsh plant community and allow more fish access.The estuary.provides habitat for some*species offish for which Management Plans have been prepared bySouth Atlantic Fishery Management Council.The managed species that could be affected by the proposed action include Oyster, White shrimp, Brown shrimp, and Red drum.Other habitats that could be affected consist of saltmarsh, brackish marsh, oyster reefs, shell banks, tidal flats and freshwater wetlands.The Atlantic States Marine Fisheries Commission (ASMFC)has Management Plans for river herrings and American Shad, Atlantic sturgeon, and American eel.Shortnose sturgeon are managed under a recovery plan by the National Marine Fishery Service (NMFS).GADNR and SCDNR have a Striped Bass Management Plan for the Lower Savannah River.Other managed species, for which Management Plans have not been prepared, that commonly occur in the Savannah River or its estuary include Alewife and Hickory shad.Lower flows are not projected by the model runs of the final or detailed alternatives, so no substantial effects on coastal zone resources or chloride intrusion are expected.Effects of the NAA Selection of the NAA and continuing with the existing SRBDCP with coordinated additions would have acceptable impacts on these biotic communities.

Effects of Alternative 1 (By comparing the alternatives Clyo gage Downstream Hydrograph to that of the NAA)Thedownstreamhydro graphs of this alternative and the NAA provide flows that greatly exceed 6000 cfs from September 1997 to September 1998.From October 1998 to November 2000 there is little variation between the flows of this alternative and the NAA and from December 2000 to 36 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 December 2003 this alternatives flows are 200-1000 cfs higher.The flows again greatly exceed 6000 cfs from January 2003 to August 2003 for this and the NAA.This alternative would have a minor positive impact on this biotic community due to the higher flows produced.Effects of Alternative 1 (By employing the EFM in conjunction with estuary information from the 1-3 April 2003 Scientific Stakeholders Workshop)Three flow/habitat relationships were analyzed for the estuary area.Instantaneous maintenance oftidal freshwater marsh (5000 cfs recommended in the workshop):

The output for this model run was 4272 cfs.This is greater than the output of3990 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.Spring seasonal maintenance of tidal freshwater marsh (8000 cfs recommended in the workshop):

The output for this model run was 4941 cfs.This is greater than the output of 4816 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.Summer and fall seasonal maintenance of tidal freshwater marsh (6000 cfs recommended in the.workshop):

->--The output for this model run was 4649 cfs.This is greater than the output of 4358 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.Effects of Alternative 2 (By comparing the alternatives Clyo gage Downstream Hydrograph to that of the NAA)The downstream hydrograph of this alternative and the NAA provides flows that greatly exceed 6000 cfs from December 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are 200-1500 cfs less than those of the NAA, from March 1999 to July 1999 there is little variation, from August 1999 to October 1999 this alternatives flows are 50-1500 cfs lower, from November 1999 to April 2000 there is again little variation, from May 2000 to June 2000 this alternatives flows are 200-4000 cfs higher, from July2000to November 2000 the flows are 300-500 cfs less and from December2000to February 2003 this alternatives flows are 50-500 cfs higher.The flows again greatly exceed 6000 cfs from March2003to August 2003 for this and the NAA.This alternative would have a minor positive impact on this biotic community due to the higher flows produced.Effects of Alternative 2 (By employing the EFM in conjunction with estuary information from the 1-3 April 2003 Scientific Stakeholders Workshop)Three flow/habitat relationships were analyzed for the estuary area.Instantaneous maintenance of tidal freshwater marsh (5000 cfs recommended in the workshop):

The output for this model run was 4357 cfs.This is greater than the output of3990 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.37 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Spring seasonal maintenance of tidal freshwater marsh (8000 cfs recommended in the workshop):

The output for this model run was 4928 cfs.This is greater than the output of 4816 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.Summer and Fall seasonal maintenance of tidal freshwater marsh (6000 cfs recommended in the workshop):

The output for this model run was 4476 cfs.This is greater than the output of 4358 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.Effects of Alternative 3 (By comparing the alternatives Clyo gage Downstream Hydrograph to that of the NAA)For October 1997 there is little variation between this alternative's flows and those of the NAA.The hydrographs of both alternatives provide flows that greatly exceed 6000 cfs from November 1997 to September 1998.From October 1998 to February 1999 this alternatives flows are predominantly 200-1500 cfs less than those of the NAA, from March 1999 to August 1999 there is little variation, from September 1999 to October 1999 this alternatives flows are 50-1500 cfs lower, from November 1999 to March 2000 there is again little variation, from April2000to June 2000 this alternatives flowsare 200-AOOO cfs higher;from July 2000 to November 2000-the flows are 300-500 cfs less and from December 2000 to January 2003 this alternatives flows are 50-500 cfs higher.The flows again greatly exceed 6000 cfs from February2003to August 2003 for this and the NAA.This alternative would have a minor positive impact on this biotic community due to the higher flows produced.Effects of Alternative 3 (By employing the EFM in conjunction with estuary information from the 1-3 April 2003 Scientific Stakeholders Workshop)Three flow/habitat relationships were analyzed for the estuary area.Instantaneous mainte l1 ance of tidal freshwater marsh (5000 cfs recommended in the workshop):

The output for this model run was 4350 cfs.This is greater than the output of 3990 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.Spring seasonal maintenance of tidal freshwater marsh (8000 cfs recommended in the workshop):

The output for this model run was 4929 cfs.This is greater than the output of 4816 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.Summer and Fall seasonal maintenance of tidal freshwater marsh (6000 cfs recommended in the workshop):

The output for this model run was 4476 cfs.This is greater than the output of 4358 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.38 DraftEA Drought Contingency Plan Update Savannah River Basin 4.6.THREATENED AND ENDANGERED SPECIES The Robust redhorse, Shoals Spider lily and the listed Shortnose sturgeon are the only Threatened or Endangered Species that would possibly be impacted by small changes in flow.The possible impacts would result from overall decreases in flow in the Augusta area during fish spawningandthe Augusta shoals area during the deer grazing periods.Effects of the NAA May 2006 Robust redhorse Selection of the NAA and continuing with the existing Drought Contingency Plan with coordinated additions would have acceptable impacts on any threateried and endangered species.The NAA provides flows primarily above 3600 cfs.Effects of Alternative 1 (By comparing the alternatives Augusta gage Downstream Hydrograph to that of the NAA)As discusseCl earlier, this aiternative provides flows that are primarily above 3800 cfs at the Augusta gauge, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200 cfs increase in predominant flows is spread across the calendar years.This would enhance spawning for the fish species and provide more protection to the Spider lily from deer grazing, so a minor positive impact would result.Effects of Alternative 1 (By employing the EFM in conjunction with Augusta Shoals information from the 1-3 April 2003 Scientific Stakeholders Workshop)As discussed earlier in Section 4.5, for the Habitat for Shad and Striped Bass, the output for this model run was 3847 cfs.This is greater than the output of 3642 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on Robust redhorse and Shortnose sturgeon.As discussed earlier in Section 4.5, for the ShoalsSpiderLily in June and July, the output for this model run was 3800 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.As discussed earlier in Section 4.5, for the ShoalsSpiderLily from August to October, the output for this model run was 3800 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.As discussed earlier in Section 4.5, for the Shoals Spider Lily in November and December, the output for this model run was 3800 cfs.This is greater than the output of3600 cfs for the NAA model run, so Alternative 1 would produce a minor positive impact on the resource.39 DraftEA Drought Contingency Plan Update Savannah River Basin Effects of Alternative 2 (By comparing the alternatives Augusta gage Downstream Hydrograph to that of the No Action Alternative)

May 2006 As discussed earlier, this alternative provides flows that are primarily above 4000 cfs with occasional drops to 3800 cfs at the Augusta gauge, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200-400 cfs increase in predominant flows is spread across the calendar years.This would enhance spawning for the fish species and provide more protection to the Spider lily from deer grazing, so a minor positive impact would result.Effects of Alternative 2 (By employing the EFM in conjunction with Augusta Shoals information from the 1-3 April 2003 Scientific Stakeholders Workshop)As discussed earlier in,section 4.5, for the Habitat for Shad and Striped Bass, the output for this model run was 3907 cfs.This is greater than the output of 3642 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on Robust redhorse and Shortnose sturgeon.As discussed earlier in Section 4.5, for the Shoals Spider Lily in June and July, the output for this model run was 3856 cfs: This is greater thari the output cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.As discussed earlier in Section 4.5, for the Shoals Spider Lily from August to October, the output for this model run was 3800 cfs.This is greater than the output of3600 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.As discussed earlier in Section 4.5, for the Shoals Spider Lily in November and December, the output for this model run was 4000 cfs.This is greater than the output of3600 cfs for the NAA model run, so Alternative 2 would produce a minor positive impact on the resource.Effects of Alternative 3 (By comparing the alternatives Augusta gage Downstream Hydrograph to that of the NAA)As discussed earlier, this alternative provides flows that are primarily above 4000 cfs with occasional drops to 3800 cfs at the Augusta gauge, while the NAA provides flows primarily above 3600 cfs.These flow trends occurred between 23 September 1997 and 30 September 2003.The 200-400 cfs increase in predominant flows is spread across the calendar years.This would enhance spawning for the fish species and provide more protection to the Spider lily from deer grazing, so a minor positive impact would result.Effects of Alternative 3 (By employing the EFM in conjunction with Augusta Shoals information from the 1-3 April 2003 Scientific Stakeholders Workshop)As discussed earlier in Section 4.5, for the Habitat for Shad and Striped Bass, the output for this model run was 3907 cfs.This is greater than the output of 3642 cfs for the NAA model run, so 40 DraftEA Drought Contingency Plan Update Savannah River Basin Alternative 3 would produce a minor positive impact on Robust redhorse and Shortnose sturgeon.May 2006 As discussed earlier in Section 4.5, for the Shoals Spider Lily in June and July, the output for this model run was 3856 cfs.This is greater than the output of3600 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.As discussed earlier in Section 4.5, for the ShoalsSpiderLily from August to October, the output for this model run was 3600 cfs.This is the same as the output of the NAA model run, so Alternative 3 would produce no adverse impact on the resource.As discussed earlier in 4.5, for the ShoalsSpiderLily in November and December, the output for this model run was 4000 cfs.This is greater than the output of 3600 cfs for the NAA model run, so Alternative 3 would produce a minor positive impact on the resource.4.7.RECREATION As evident in past droughts, recreation experiences diminish on Hartwell and J.Strom Thurmond Lakes.Some public boat ramps and private docks are out of the water as the lake level recedes.In addition, tree stumps and sand bars are exposed in the lakes.For some boaters, continued use.o{the'iakes poses*a senou*s threat to*damagingboats and fujuring persons.For swimming outside the Corps of Engineers' operated designated areas increases the potential for swimming fatalities.

4.7.1.Boat-Launching Ramps and Private Docks Hartwell Lake An examination of the number of days water surface elevations are at and below each lake level over the period of record of drought for each alternative provides a macro view of impacts on recreation relative to the No Action Alternative (Table 6).Table 8: Hartwell Lake: Days At and Below Lake Level by Alternative Lake Level***658657656 655 654 653 652 651 NAA 1556 1485 1402 1286 1159 1053 867 623 Alt 1 1557 1491 1343 1275 1161 1051 924 805 Alt2 1557 1464 1336 1264 1145 875 657 540 Alt3 155714641334 1263 1142 877 655 539 Lake Level650649648 647 646645644 643 642 641 NAA 502 393 284 173 49 000 0 0 Alt 1690634 566 459 316 234 161 102 61 18 Alt2 444 335 174 91 0 00000 AIt3 442 331 173 82 0 00000 At and below lake level 658 feet msl, some boat-launching ramps become unusable.Table 8 shows that there is little change between Alternatives 1, 2, and 3 and the NAA in the number of 41 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 days at and below each lake level from 658 through 654 feet ms!.Starting at and below lake level 653, there is a consistently measurable change in the number of days at and below each lake level between Alternative 2 and 3andthe NAA.For example, when the lake level is at and below 653 feet msl, Alternative 2 provides an additional 178 days of recreation for 6 boat ramps while Alternative 1 provides two less days of recreation than the NAA.Changes become consistently measurable for Alternative 1 at and below lake level 652.Table 9 shows the number of unusable and useable public boat-launching ramps by lake level in one-foot increments.

In Table 10 is a comparison of the NAA and Alternative 1 including the difference in the number of days at and below each lake level and the number of publiclaunching ramps adversely impacted.Table 9: Hartwell Lake: Number of Unuseable and Useable Ramps by Lake Level At And Below Additional Ramps Unuseable Total Ramps Unuseable Useable Ramps By 1 Foot Lake Level Bv 1 Foot Drop In Lake Bv 1 Foot Drop In Lake Level Drop In Lake Level 659 0 0 95 658 6 6 89 657 6 12 83--656.....1 13--82 655 3 16 79 654 1 17 78 653 6 23 72 652 7 30 65 651 9 39 56 650 5 44 51 649 3 47 48 648 1 48 47 647 1 49 46 646 0 49 46 645 1 50 45 644 0 50 45 643 3 53 42 642 0 53 42 641 0 53 42 Effects of the NAA The NAA's minimum lake level elevation during the modeled drought of record is estimated at 645.6 feet ms!.Therefore, 46 boat-launching ramps (48 percent)would be useable at the worst period of drought under the NAA.Currently, there are an estimated 10,500 private boat docks in Hartwell Lake.The SRBDCP, March 1989, approximated 5,400 private docks.It was roughly estimated that about 50 percent of these private docks were unusable at 652 feet ms!.Even with the ability and willingness to chase the water, the percentage of docks now unusable at 652 feet msl would likely be greater than 50 percent since newer developments are located in shallow coves.Hence, at and below 652 feet msl more than 50 percent of these private docks would likely be unusable for 867 days.42 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Effects of Alternative 1 Alternative 1's minimum lake level elevation is estimated at 640.01 feet msl.Therefore, 42 (44 percent)boat-launching ramps would be useable at the worst period of drought under Alternative 1.According to a survey conducted by Lake Hartwell Association in 2003, most of the people surveyed (80 percent)considered boating and water sports safe when lake levels are above 652 feet msl.In 2002, when lake levels were below 652 feet msl all year, the survey reveals an estimated 63 percent drop in the number of boating trips taken from non-drought years.This number corresponds to the estimated 61 percent drop in visits according to the Zapata report.Therefore, one may conclude, based on these reports, that once lake levels drop at and below 652 feet msl approximately 37 to 39 percent of all boating trips conducted indrought years would be impacted.As shown in Table 10, above 652 feet msl, there are minor differences in the number of days between the NAA and Alternative 1 at and below each lake level.At and below 652 feet msl there are more measurable negative differences between the NAA and Alternative 1 in the number of days at and below each lake level.However, by the time lake levels are at and below 652 feet msl, it is estimated that 61 to 63 percent ofthe all boating trips conducted in non-drought years have been displaced.

Therefore, Alternative 1 is considered to have minor adverse impacts on the number of boating trips beginning at and below lake level 652 feet msl.Table 10: Hartwell Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 1 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment Lake Level658657656 655 654653652 651 NAA 1556 1485 1402 1286 1156 1053 867 623 Alt 1 1557 1491 1343 1275 1158 1051 924 805 Difference 6 59 11-2 2-57-182#of Ramps Out66131679 Lake Level650649 648 647 646645644 643 642 641 NAA 502 393 284 173 4900000 Alt 1 690 634 566 459 316 234 161 102 61 18 Difference

-188-241-282.-282-267-234-161-102-61-18#of Ramps Out5311010300 Since there is very little difference in the number of days between the NAA and Alternative 1 above lake level 652, Alternative 1 is considered to have minor adverse impacts on private docks at Hartwell Lake relative to the NAA.Effects of Alternative 2 The minimum lake level for Alternative 2 is 646.04 feet msl.Therefore, 46 (48 percent)public boat-launching ramps would be useable at the worst period of the drought.At each lake level there are more days available to use the boat-launching ramps than the NAA.Hence, Alternative 2 has a positive impact on boat-launching ramps at Hartwell Lake.43 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Table 11: Hartwell Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 2 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment Lake Level 658657656 655 654 653 652 651 NAA15561485 1402 1286 1159 1053 867 623 Alt2 1557 146413361264 1145 875 657 540 Difference

-1 21 66 22 14 178 210 83#of Ramps Out661 3 1 679 Lake Level 650 649 648 647646645644643 642 641 NAA 502 393 284 173 49 00000 Alt2 444 335 174 9100 0000 Difference5858 110 82 4900000#of Ramps Out5311010300 At every lake level there are more days available to use private docks.Therefore, Alternative 2 has positive impacts on private docks at Hartwell Lake relative to the NAA.Effects of Alternative 3 The miIrimum lake level for Alternative 3 is 646.04 feet ms!.Therefore, 46 (48 percent)launching ramps would be useable at the worst period of the drought.At each lake level there are more days available to use the boat-launching ramps than the NAA.Hence, Alternative 3 has a positive impact on boat-launching ramps at Hartwell Lake.Table 12: Hartwell Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 3 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment Lake Level 658 657656655 654 653 652 651 NAA 1556 1485140212861159 1053 867 623 Alt3 1557 1464 1334 1263 1142 877 655 539 Difference

-1 21 68 23 17 176 212 84#of Ramps Out66131 679 Lake Level 650 649 648 647646645644643 642 641 NAA 502 393 284 173 49 0000 0 Alt3 I 442 331 173 82000000 Difference6062 111 91 49 0000 0#of Ramps Out531101 0300 At every lake level there are more days available to use private docks than the NAA.Therefore, Alternative 3 has positive impacts on private docks at Hartwell Lake relative to the NAA.RBRLake The minimum lake level for the NAA is 473.74 feet msl;Alternative I is 473.72 feet msl;and Alternative 2 and 3 are 471.22 feet ms!.Lake level would have to be at 466 feet msl and lower 44 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 to have adverse impacts on the boat-launching ramps in the RBR Lake.Therefore, for all the alternatives, there are no adverse impacts on public boat-launching ramps in RBR Lake.There are no private docks on the RBR Lake.JSTLake An examination ofthenumbers of days at and below each lake level for each alternative provides a macro view of the impacts on recreation of each alternative relative to the NAA (Table 11).Table 13: JST Lake: Days At and Below Lake Level by Alternative Lake Level328327326325 324 323 322 321 NAA 1557 1467 137112401119 1014 860 637 Alt 1 1583 1522 1427 1277 1130 1037 915 808 Alt2 151314051226 1008 914 754 654 566 Alt3 1512 1402 1223 992 913 754 653 560 Lake Level 320319318317316315 314 313 312 311 NAA 496 385 236 57 00000 0 AId 688 631 559 385 273" 159 13000 Alt2 413 224 127 65300000 Alt3 409 222 126 50 300000 Table 13 shows that there is little change between the alternatives and the NAA in the number of days at for lake levels at and below 328 and at and below 327 feet ms!.Starting at and below lake level 326 feet msl, there is a measurable change in the number of days at and below each specific lake level between Alternative 2 and 3 and the NAA.As shown in Table 14, at and below lake level 326 feet msl, boat-launching ramps start to become unusable.For example, when the lake level is at and below 326 feet msl, Alternative 2 (Table 16)provides an additional 145 days of recreation for 1 boat ramp while Alternative 1 (Table 15)provides 56 less days of recreation than the NAA.Changes become consistently measurable for Alternative 1 at and below lake level 323.There are 84 public boat-launching ramps and marinas located on JST Lake.Above lake elevation 326 feet msl all ramps are useable and allow for the launching of boats with up to 3 feet of draft.At and below lake level 326 feet msl, the first boat-launching ramp becomes unusable.At and below lake level 325 feet msl, 4 more or a total of 5 boat-launching ramps become unusable.At and below lake level 324 feet msl, 7 more or a total of 12 boat-launching ramps become unusable.At and below lake level 323 feet msl, 5 more or a total of 17 (20 percent)boat-launching ramps become unusable while 67 (80 percent)remain useable.At and below lake level 317 feet msl, 33 (39 percent)boat-launching ramps become unusable.At and below lake level 315 feet msl, 46 (55percent)boat-launching ramps become unusable.Alllaunching ramps would become unusable at 306 feet ms!.45 DraftEA Drought Contingency Plan Update Savannah River Basin Table 14: Number of Un useable and Useable Ramps by Lake Level May 2006 At and Below Additional Ramps Total Ramps Useable Ramps by Lake Level Un useable by I-Foot Unuseable By I-Foot I-Foot Drop in Lake Drop in Lake Drop in Lake 327 0 0 84 326 1 1 83 325 4 5 79 324 7 12 72 323 5 17 67 322 1 18 66 321 5 23 61 320 2 25 59 319 0 25 59 318 6 31 53 317 2 33 51 316 6 39 45 315 7 46 38 314 19 65 19 Effects of the NAA The NAA's minimum lake level during the modeled drought of record is estimated at 316.39 feet msl.Therefore, 51 public boat-launching ramps (61 percent)would be useable at the worst period of drought under the NAA.At and below lake level 326 feet ms1, boat-launching ramps start to become unusable.At and below lake level 326 feet ms1, 1 boat-launching ramp is unusable for 1,371 days.At and below lake 1eve1325 feet ms1, 4 additional boat-launching ramps become unusable for 1,240 days.At and below lake 1eve1324 feet ms1, 7 additional boat launching ramps become unusable for 1,119 days.The total number of unusable boat-launching ramps continues to increase to 33 at and below 317 feet msl.Currently, there are approximately 1,500 private boat docks on the JST Lake.This is a 25 percent increase from the March 1989 SRBDCP report.In that report, at 322 feet ms1, about 50 percent of the docks were considered unusable.At 313 feet ms1, 95 percent of the private docks were considered as unusable.Effects of Alternative 1 Alternative l's minimum lake level elevation is estimated at 313.73 feet msl.Therefore, 36 of all public boat-launching ramps (42 percent)would be useable at the worst period of drought under Alternative 1.At and below lake 1eve1326 feet ms1, 1 boat-launching ramp is unusable for 1,427 days for Alternative 1 versus 1,371 days for the NAA.Alternative 1 is unusable for 56 days more than the NAA representinga4 percent change at and below lake level 326 feet msl.At and below lake 1eve1325 feet ms1, 4 additional boat-launching ramps become unusable for 1,277 days.Alternative 1 is unusable for 37 days more than the NAA at and below lake level 325 feet ms!.At and below lake level 324 feet ms1, 7 additional boat-launching ramps become unusable for 1,130 days.Alternative 1 is unusable for 11 days more than the NAA at and below lake 1eve1324 feet ms!.Alternative 1 is unusable for 24 and 55 days more than the NAA at and 46 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 below lake level 323 and 322 feet msl, respectively.

Above 322 feet msl, there are minor changes in number of dayswhileat and below 322 feet msl there are more measurable negative changes in the number of days boat ramps are available.

However, by the time lake levels are at and below 322 feet msl, it is estimated that 61 to 63 percent of the visits have been displaced.

Therefore, Alternative 1 is considered to have minor adverse impacts on boating access at JST Lake.Table 15: JST Lake: Days At and Below Lake Level-Comparison of NAA and Alternative 1 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment Lake Level328327326325324323 322 321 NAA 1557 1467 1371 1240 1119 1014 860 637 Alt 1 15831522142712771130 1037 915 808 Difference

...26-55-56-37-11-23-55-171#of Ramps Out001 4 7 515 Lake Level320319318317 316315314 313 312 311 NAA 496 385 236 57 000000 AU 1 688 631 559 385 273 159 13000 Difference-192-246-323-328-273-159-13000.#of Ramps Out206 2 6 7 19 0 0 0 At and below lake level 322 feet msl, 50 percent of the private docks would be unusable for 55 days more than the NAA.In addition, the NAA lake levels do not drop below 317 feet msl whereas Alternative 1 drops to 313.73 feet ms!.Therefore, additional docks will be adversely impacted under Alternative 1.Hence, Alternative 1 has minor adverse impacts on private docks at JST Lake relative to the NAA.Effects of Alternative 2 The minimum lake level for Alternative 2 is 315.64 feet ms!.Therefore, 42 boat-launching ramps would be useable (61 percent)at the worst period of drought for Alternative 2.At and below lake level 326 feet msl, 1 boat-launching ramp is unusable for 1,226 days for Alternative 2 versus 1,371 days for the NAA.Alternative 2 is useable for 145 days more than the NAA at and below lake level 326 feet ms!.At and below lake level 325 feet msl, 4 additional boat-launching ramps become unusable for 1,008 days.Alternative 2 is useable for 232 days more than the NAA at and below lake level 325 feet ms!.At and below lake level 324 feet msl, 7 additional boat-launching ramps become unusable for 914 days.Alternative 2 is useable for 205 days more than the NAA at and below lake level 324 feet ms!.Alternative 2 is useable for 260 and 206 days more than the NAA at and below lake levels 323 and 322 feet msl, respectively.

Alternative 2 is considered to have a positive impact on boat-launching ramps at JST Lake since there is a measurably consistent increase in the number of days that boat-launching ramps are available especially above lake level 322 feet mslfrom the NAA.47 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Table 16: JST Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 2 Including Number of Boat-Launching Ramps Impacted by 1 Foot Increment Lake Level328327 326 325 324 323 322 321 NAA 1557 1467 137112401119 1014 860 637 Alt2 1513 1405 1226 1008 914754654 566 Difference 44.62 145 232 205260206 71#of Ramps Out 0 014 751 5 I Lake Level 320 319 318 317 I 316315314313312 311496 385 236 57=f0 0000 0 413 224 127 65300000 I Difference 83 161 109-8-3 00000 I#of Ramps Out 2 0 6 2 16 7 19000 Above lake level 322 feet msl, there is a measurable increase in the number of days that private docks are available compared to the NAA.Therefore, Alternative 2 is considered to have positive impacts on private docks at JSTLakerelative to the NAA.Effects of Alternative 3 The-miniinum lake level for Alternative 3 is fi5.64 feet msl.Therefore, 42 ramps would be useable (61 percent)at the worst period of drought for Alternative 3.At and below lake level 326 feet msl, 1 boat-launching ramp is unusable for 1,223 days for Alternative 3 versus 1,371 days for the NAA.Alternative 3 is useable for 148 days more than for the NAA at and below lake level 326 feet msl.At and below lake level 325 feet msl, 4 additionallaunching ramps become unusable for 992 days.Alternative 3 is useable for 248 days more than the NAA at and below lake level 325 feet msl.At and below lake level 324 feet msl, 7 additional boat-launching ramps become unusable for 913 days.Alternative 3 is useable for 206 days more than the NAA at and below lake level 324 feet msl.Alternative 3 is useable for 260 and 206 days more than the NAA at and below lake levels 323 and 322 feet msl, respectively.

Alternative 3 is considered to have a positive impact on boat-launching ramps at JST Lake since there is a measurably consistent increase in the number of days that boat-launching ramps are available especially above lake level 322 feet msl from the NAA.Above lake level 322 feet msl, there is a measurable increase in the number of days that private docks are available compared to the NAA.Therefore, Alternative 3 is considered to have positive impacts on private docks at JST Lake relative to the NAA.48 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Table 17: JST Lake: Days At and Below Lake Level-Comparison ofNAA and Alternative 3 Inclnding Number of Boat-Launching Ramps Impacted by 1 Foot Increment Lake Level 328 327 326325324 323322321 NAA15571467 1371 1240 1119 1014 860 637 Alt3 1512 1402 1223 992 913 754 653 560 Difference 45 65 148248206 260 207 77#of Ramps Out001 47515 Lake Level 320 319 318317316315314 313 312 311 NAA 496 385 236 57 0 000 0 0 Alt3 409 222 126 50 3 000 0 0 Difference 87 163 110 7-3 000 0 0#of Ramps Out206267 1900 0 4.7.2.Swimming Swimming at beach areas usually occurs from May-September.

Therefore, it is important to identitY the differences between the NAAandAlternatives 1, 2 and 3 during this period of time.Also, designated swimming areas are considered useable by lake managers with greater than 3 fe.et of water.Hence, only a change inthe number of swimming days available__greater than lake_level 657 feet msl at Hartwell and 327 feet msl at JST would constitute an impact on swimming.Hartwell Lake At Hartwell Lake, there are 22 Corps of Engineer's operated swimming beach areas located within 13 recreation areas.At and below lake level 654 feet msl, all designated swimming areas are completely dry.Designated swimming areas are useable with greater than 3 feet of water.Hence, a change in the number of swimming days available greater than lake level 657 from the NAA would constitute an impact on swimming.Effects of the NAA Designated swimming areas are completely dry 1,159 days at and below 654 feet msl during the modeled drought of record.Designated swimming areas are above 3 feet of water for 177 days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.Effects of Alternative 1 Designated swimming areas are above 3 feet of water for 177 days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.Therefore, Alternative 1 provides no adverse impact on swimming days available.

Effects of Alternative 2 Designated swimming areas are above 3 feet of water for 204 days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.This constitutes a 15 percent increase in the number of swimming days compared to the NAA.Therefore, Alternative 2 provides a minor positive impact on swimming days available.

49 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Effects of Alternative 3 Designated swimming areas are above 3 feet of water for 204 days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.This constitutes a 15 percent increase in the number of swimming days compared to the NAA.Therefore, Alternative 3 provides a minor positive impact on swimming days available.

RBRLake At RBR, there are no Corps of Engineer's operated designated swimming beach areas.JSTLake At JST Lake, there are 18 swimming beach areas.At and below lake level 324 feet msl, the designated swimming beaches become completely dry.Designated swimming areas are useable with greater than 3 feet of water.Hence, only a change in the number of swimming days available above lake level 327 from the NAA would constitute an impact on swimming.Effects of the NAA Designated swimming areas are completely dry 1,119 days at and below lake level 324 feet msl during the modeled drought of record.There are 171 total days usable for swimming above lake level 327 or above 3 feet of water in the designated swimming area between the months of May and September with a drought of fecoid like the one from 1 July 1998 to*22 March 2003.Effects of Alternative 1 Designated swimming areas are above 3 feet of water for 171 total days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.Since the swimming days available are the same for Alternative 1 and the NAA, Alternative 1 provides no adverse impact on swimming days available.

Effects of Alternative 2 Designated swimming areas are above 3 feet of water for 176 total days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.This isa3 percent increase in the number of swimming days available from the NAA to Alternative 2.Therefore, Alternative 2 provides relatively no adverse impacts on swimming days available.

Effects of Alternative 3 Designated swimming areas are above 3 feet of water for 176 total days between the months of May and September with a drought of record like the one from 1 July 1998 to 22 March 2003.This isa3 percent increase in the number of swimming days available from the NAA to Alternative 3.Therefore, Alternative 3 provides relatively no adverse impacts on swimming days available.

4.8.WATER SUPPLY Water supply curtailments during drought are the performance measures used to determine the impacts ofthe alternatives in comparison to the NAA.50 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Hartwell Lake There are 8 water supply users on Hartwell Lake.Three (Anderson County Joint Municipal Water System, City of Lavonia, and Hart County Water and Sewer)currently hold water storage contracts in Hartwell Lake with the US Army Corps of Engineers, Savannah District.Five have riparian rights (City of Hartwell, Clemson University, Clemson Golf Course, J.P.Stevens, and Milliken Company).The highest intake elevation according to the Savannah River Basin Drought Contingency Plan, March 1989, is 638.33 feet msl.This is 8 feet below the lowest water level during the drought of record (646 feet msl)for the No Action Alternative and Alternatives 2 and 3.It is 2 feet below the lowest water level (640.05 feet msl)for Alternative 1.Therefore, there would be no adverse impacts to water supply users in Hartwell Lake for all the alternatives.

RBRLake There are 6 water supply users on RBR Lake.Two (City of Elberton and Santee Cooper)currently holding water storage contracts in RBR Lake with the US Army Corps of Engineers, Savannah District.Threehaveriparian rights (RBR State Park Golf Course, Mohawk Industries, and Calhoun Falls).The City of Abbeville is in relation to mitigation for RBR construction.

The highest intake elevation according to the SRBDCP, March 1989, is 457.5 feet msl.This is 13.7 feet below the lowest water level during the drought of record (471.2 feet msl)for the NAA and both alternatives.--Theiefore, there would be no adver'se-impactsto wateisupplyusers in RBR Lake for all the alternatives.

JSTLake There are 8 water supply users on JST Lake.Eight (City of Lincolnton, City of Washington, City of McCormick, City of Thomson, Columbia County, Savannah Lakes POA Monticello Golf Course and Savannah Lakes POA Tara Golf Course)currently holding water storage contracts in JST Lake with the US Army Corps of Engineers, Savannah District.Hickory Knob State Park Golf Course has riparian rights.The highest intake elevation according to the SRBDCP, March 1989, is 307 feet msl.This is 9 feet below the lowest water level during the drought of record (316 feet msl)for the NAA and Alternatives 2 and 3.It is 7 feet below the lowest water level (314 feet msl)for Alternative 1.Therefore, there would be no adverse impacts to water supply users in the JST Lake for all the alternatives.

Downstream of JST Lake Water supply users downstream include the Augusta Canal and Shoals users, users with intakes in the NSBL&D pool including North Augusta, Mason's Sod, Kimberly Clark, Urquhart Station, PCS Nitrogen, DSM Chemical and General Chemical and users below NSBL&D (Water Supply Authority, City of Savannah M&I Plant, and Savannah National Wildlife Refuge).These water supply users currently require a minimum normal flow from JST of3,600 cfs.The NAA and all three alternatives meet this criterion.

Therefore, there is no adverse impact on water supply users with intakes below the JST Lake for the NAA and all three alternatives.

There are impacts on projected water demands for the Augusta Canal and Shoals users.Augusta, Georgia, Utilities Department projected average values for Augusta Canal water needs (in cfs)out to 2035 in ten year increments for the summer, winter and spring periods as shown in Table 18.51 DraftEA Drought Contingency Plan Update Savannah River Basin Table 18: Projected Average Values for Augusta Canal Water Needs (cfs)YEAR SUMMER WINTER SPRING 2005 3,761 3,567 3,685 2015 4,0033,7683,912 20254,2964,012 4,186 2035 4,353 4,307 4,346 May 2006 Effects of the NAA The difference between the projected Augusta Canal average water needsandthe NAA JST flows (cfs)determine the impact on projected water needs for the Augusta Canal in comparison to the NAA.The 5-year average JST flows for the summer period (June thru November)is.4,672 cfs.It exceeds the Augusta!Richmond County summer projected average value of 4,353 for Augusta Canal and Shoals water demands through 2035.Analyzing the average flow for the summer period on an annual basis over the drought of record against the Augusta Canal water demands indicates that 2005 water demands are met.However, there would be a shortage in summer flows during the fourth (3,808 cfs)and fifth water (3,804 cfs)year ofthe drought of record relative to the Augusta!Richmond County's projected average water demands for year...20 i 5-(4,003 Cis).Measillill g the di'ought of recordagciillsfthe projected Augusta*Canal average water demands of 4,296 in 2025 and 4,353 in 2035 indicates a greater shortage during the fourth and fifth years of a drought of record.Table 19: NAA JST Average Annual Flows by Water Year for Summer Period Summer WYl 5,982 WY2 5,502 WY3 4,658 WY4 3,808 WY5 3,804 The 5-year average JST flows for the winter period (December thru February)is 4,469 cfs.It exceeds the winter projected average value of 4,307 for Augusta Canal water demands through 2035.Analyzing the average flow for the winter period on an annual basis over the drought of record indicates that the flow in the third (3,642 cfs)and fourth (3,684 cfs)water years of a drought of record would not meet the Augusta!Richmond County's projected average water demands (3,768 cfs)for year 2015 and beyond[2025 (4,012 cfs)and 2035 (4,307 cfs)]Table 20: NAA JST Average Annual Flows by Water Year for Winter Period Winter WYl 5,551 WY2 4,997 WY3 3,642 WY4 3,684 The 5-year average JST flows for the spring period (March thru May)is 5,143 cfs.It exceeds the spring projected average value of 4,346 for Augusta Canal water demands through 2035.Analyzing the average flow for the spring period on an annual basis over the drought of record indicates that there would be a shortage in Spring flows during the first, third and fourth water year period of a drought of record water demands for year 2015 would not be met.Measuring 52 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 the drought of record against the projected Augusta Canal average water demands in 2025 indicates a shortage in the first, second, third and fourth year of the drought of record and in 2035 the first, second, third, and fourth years of the drought would come short of meeting projected average demands of 4,346 for the Augusta Canal.Table 21: NAA JST Average Annual Flows by Water Year for Spring Period WY2 4,264 WY3 3,687 WY5 9,969 Effects of Alternative 1 To determine the impact of each alternative, JST flows for each alternative were compared to the NAA to determine whether JST flows increased or decreased.

If they increased, theriAugusta**

Canal water needs are no worse off and impacts are positive.If they decreased; then Augusta Canal water needs may be worse contingent upon the extent of the decrease relative to the projected water needs for a given year.During the summer period, Alternative 1 provides the same or increased flows during the fust, third, fourth and fifth water years of a drought of record while decreasing flows by 41 cfs in the second wafetyear rdative to the NAA.**The decrease mthe second wateryear is insignificaiit'**

since it meets water demands out to 2035.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments.

Therefore, the impact of Alternative 1 on the Augusta Shoals and Canal curtailments would be positive.Table 22: Alternative 1 JST Average Annual Flows by Water Year for Summer Period Summer WY2 5,461 WY4 4,498 WY5 4,147 During the winter period, Alternative 1 provides increased flows during the fust, third, and fourth water years of a drought of record while decreasing flows in the second and fifth water years relative to the NAA.The decrease in the second water year is mute since it meets water demands out to 2035.However, the decrease in the fifth water year no longer meets 2025 demands and beyond in which the NAA could meet.The increased flows in the third and fourth water years would help meet 2015 demands in which the NAA could not meet.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments in the third and fourth water years, but less water for the Augusta Shoals and/or more Canal curtailment in the fifth water year.Therefore, the impact of Alternative 1 on the Augusta Shoals and Canal curtailments would be minor positive since earlier drought years now meet water demand projections.

Table 23: Alternative 1 JST Average Annual Flows by Water Year for Winter Period Winter WY2 4,351 53 WY3 3,951 WY4 3,885 WY5 3,946 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 During the spring period, Alternative 1 provides increased flows throughout a drought of record.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments.

Therefore, the impact of Alternative 1 on the Augusta Shoals and Canal curtailments would be positive.Table 24: Alternative 1 JST Average Annual Flows by Water Year for Spring Period WY2 4,525 WY3 3,990 WY5 5,594 Effects of Alternative 2 During the summer period, Alternative 2 provides increased flows duringfourth and fifth..water years of a drought of record while decreasing flows in the fITst, second and third water*years relative to the NAA.The decrease in the fITst and second water year is mute since it meets water demands out to 2035.However, the decrease in the third water year becomes short by 26 cfs of meeting the 2035 water demands.Although there is less flow in the earlier years of a drought of record, the impact on projected demands is insignificant in the fITst, second and third water years.There would be more water for the Augusta Shoals and/or less Canal curtailments iIi the fourth and fifth Water years meeting 2015'demands.Therefore, the impact of Alternative 2 on the Augusta Shoals and Canal curtailments would be positive.Table 25: Alternative 2 JST Average Annual Flows by Water Year for Summer Period WYl 5,880 WY2 5,094 WY3 4,327 WY4 4,187 WY5 4,117 During the winter period, Alternative 2 provides increased flows during the fITst, third, and fourth water years of a drought of record while decreasing flows in the second and fifth water years relative to the NAA.The decrease in the second and fifth water years no longer meet 2025 demands and beyond in which the NAA could meet.The increased flows in the third and fourth water years would now meet 2015 and 2025 water demand projections, respectively, in which the NAA could not meet.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments in the third and fourth water years, but less water for the Augusta Shoals and/or more Canal curtailment in the second and fifth water years.The adverse impacts of Alternative 2 on the Augusta Shoals and Canal curtailments would be offset by positive impacts.Therefore, Alternative 2 is considered to have no adverse impacts.Table 26: Alternative 2 JST Average Annual Flows by Water Year for Winter Period WYl 5,700 WY2 3,960 WY4 4,038 During the spring period, Alternative 2 provides increased flows throughout a drought of record.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments.

54 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Therefore, the impact of Alternative 2 on the Augusta Shoals and Canal curtailments would be positive.Table 27: Alternative 2 JST Average Annual Flows by Water Year for Spring Period WYl 4,192 WY2 4,964 WY4 3,911 WY5 11,457 Effects of Alternative 3 During the summer period, Alternative 3 provides'increased flows during the fourth and fifth water years of the drought of record while decreasing flows in the first, second and third water years relative to the NAA.The decrease in the first and second water year is mute since it meets water demands out to 2035.However, the decrease in the third water year becomes short'by 26 cfs of meeting the 2035 water demands.Although there is less flow in the earlier years of a drought of record, the impact on projected demands is insignificant in the first, second and third water years.There would be more water for the Augusta Shoals and/or less Canal curtailments in the fourth and fifth water years meeting 2015 demands.Therefore, the impact of Alternative 3 on the Augusta Shoals and Canal curtailments would be positive."'-Table28:

Alternative 3 JSTAverage Annual Flows by Water Year for'Summer Period Summer WY2 5,094 WY3 4,327 WY5 4,040 During the winter period, Alternative 3 provides increased flows during the first, third, and fourth water years of the drought of record while decreasing flows in the second and fifth water years relative to the NAA.The decrease in the second and fifth water year no longer meet 2025 demands and beyond that the NAA could meet.The increased flows in the third and fourth water years would help meet 2015 and 2025 water demand projections, respectively, that the NAA could not meet.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments in the third and fourth water years, but less water for the Augusta Shoals and/or more Canal curtailment in the second and fifth water years.The impact of Alternative 3 on the Augusta Shoals and Canal curtailments would be offset by positive and adverse impacts.Therefore, Alternative 3.is considered to have no adverse impacts.Table 29: Alternative 3 JST Average Annual Flows by Water Year for Winter Period WYl 5,700 WY2 3,959 WY3 3,981 WY5 3,810 During the spring period, Alternative 3 provides increased flows throughout a drought of record.As a result, there would be more water for the Augusta Shoals and/or less Canal curtailments.

Therefore, the impact of Alternative 3 on the Augusta Shoals and Canal curtailments would be positive.55 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Table 30: Alternative 3 JST Average Annual Flows by Water Year for Spring Period WYl 4,192 WY2 4,964 WY3 3,938 WY5 11,661 4.9.HYDROPOWER Effects of NAA The NAA output indicates that during the drought of record there were 139 shortages accounting for a total shortage of 748,302 MWh.Effects of Alternative 1 Alternative 1 output indicates that during the drought of record there were 144 shortages accounting for a total shortage of701,211 MWh.This implies a reduction in shortages of 47,091 MWh.This represents a 6.3 percent reduction in shortage from the NAA to Alternative 1.Therefore, Alternative 1 provides a positive impact in terms of fewer shortages for hydropower.

Effects of Alternative 2 The results for Alternative 2 indic:ate Jhat 4uring the drought of record there were 138 shortages accounting for a total shortage of 749,468 MWh.This implies an increase in shortages of 1,165 MWh.This representsa0.156 percent increase in shortages ofMWh from the NAA to Alternative 2.Therefore, Alternative 2 provides no meaningful adverse impact in terms of increased shortages.

Effects of Alternative 3 The results for Alternative 3 indicate that during the drought of record there were 137 shortages accounting for a total shortage of 759,002 MWh.This implies an increase in shortages of 10,700 MWh.This represents a 1.43 percent increase in shortages ofMWh from the NAA to Alternative 3.Therefore, Alternative 3 provides a minor adverse impact in terms of increased shortages.

Energy Shortages (MWh)-660000-680000

-700000

-720000

-740000-760000 No Action Alternative 1 Alternative 2 Alternative 3 56 DraftEA Drought Contingency Plan Update Savannah River Basin 4.10.CULTURAL RESOURCES Effects of the No Action Alternative The NAA would have no additional adverse impacts to cultural resources as the existing SRBDCP of March 1989 with pumped storage operation would continue to be used.May 2006 Effects of Alternative 1 Since the maximum pool levels at all lakes will remain the sameandthe minimum pool levels would be higher (reducing erosion of submerged archaeological resources), Alternative 1 would have no additional adverse impacts to cultural resources.

Effects of Alternative 2 This would have the same effect on pool levels as Alternative 1, so this action would have no additional adverse impacts to cultural resources.

Effects of Alternative 3 This would have the same effect on pool levels as Alternative 1, so this action would have no additional adverse impacts to cultural resources.

4.11.ENVIRONMENTAL JUSTICE Effects of the NAA The NAA would have no adverse impacts on environmental justice as the existing SRBDCP of March 1989 with pumped storage operation would continue to be used.Effects of Alternative 1 This action would have effects along the entire length of the Savannah River Basin.The areas adjacent to the riverbanks and lakes do not support disproportionate concentrations of minority or low-income communities.

Minority or low-income populations do not recreate on the river in disproportionate numbers.As a result, this alternative would not result in disproportionately high and adversehumanhealth or environmental impacts on minority or low-income populations in the United States.It therefore complies with Executive Order 12898,"Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations".

Effects of Alternative 2 This alternative would have the same effect along the river as Alternative 1, so this action would not result in disproportionately high and adverse human health or environmental impacts on minority or low-income populations in the United States.Effects of Alternative 3 This alternative would have the same effect along the river as Alternative 1, so this action would not result in disproportionatelyhighand adverse human health or environmental impacts on minority or low-income populations in the United States.4.12.CUMULATIVE EFFECTS Council on Environmental Quality regulations (40 CFR 150.7)require an analysis of the cumulative impacts resulting from the incremental impact of an action when added to other past, 57 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 present, and reasonably foreseeable future actions, regardless of who undertakes these other actions.Cumulative impacts can result from individually minor, but collectively significant, actions.This cumulative impacts section of the EA addresses only the cumulative effects arising from considering the Proposed Action in combination with other ongoing or proposed actions in the Savannah River Basin.The Savannah River does not function as it originally did, because of various changes.Several dams cross its flow, holding back high spring flows and raising lowsummer flows.Peaking operations at hydropower plants make the flows irregular during the course of day and week in some areas, rather than being primarily in response to rainfall events and seepage from adjacent wetlands.Numerous withdrawals of water occur, some for municipal use, some for industrial purposes, and others to aid adjacent recreation.

The number of users of the river has increased dramatically.

The ponded lakes that occur upstream of the dams provide sources for several types of recreation, and those sites are used heavily for those purposes.Primarily, fishermen use the free-flowing portions ofthe river, and their numbers have continued to increase with the overall growth in regional population.

If it were not for the multiple users ofthe river and lakes as they now exist, there would be little concern about the amount of water flowing in the river during a drought.But the goals and activities of many individuals, organizations, corporations, and government agencies are now affected by the amount of water in J.Strom Thurmond Lake and the amount that is discharged to flow down to the ocean.Those users are expected to continue to conduct their activities on the lake and in the river in the future.Although Savannah District is not aware of any specific plans to substantially increase the use of waters in the Savannah River Basin, we do expect some growth in both the number of users and the amount of water that is desired to be withdrawn from the lakes and river.We recognize that the Savannah River is viewed by some located in other river basins as a ready source of clean water for their needs.If/when the regulating government agencies agree that additionalbasin transfers can occur, stresses on existing uses along the entire length of the Savannah River basin will increase to some degree.In summary, flows in the Savannah River have been substantially modified over time, but the basin still presents a multitude of opportunities for the use and enjoyment of this valuable resource.The number of people desiring to use or benefit from this resource continues to increase.The uses vary seasonally, with lower demands placed on the aquatic ecosystem during the winter months.As a drought intensifies or continues in duration, the stress on both the natural ecosystem and human uses of the resources increase.Impacts would result primarily from increases in water usage and not from relatively small changes in the allocation of water considered in the Proposed Action or any of the detailed alternatives, so no adverse cumulative impacts would be expected.Cumulative impacts could result from a more comprehensive plan with larger changes in the allocation of water.58 DraftEA Drought Contingency Plan Update Savannah River Basin

5.0 CONCLUSION

May 2006 This Environmental Assessment considers the potential environmental impacts of the proposed project.The impacts listed in Table 31 are similar for the three alternatives, but Alternative 1 has a minor adverse impact on recreation, boat-launching ramps and docks at Hartwell and J.Strom Thurmond Lakes, while Alternative 2 has positive impacts on these resources.

Alternative 3 has a minor adverse impact on hydropower, while Alternative 2 has no adverse impact.Therefore Alternative 2 is the preferred alternative.

The Proposed Action (Alternative 2)would update the Savannah River Basin Drought Contingency Plan of March 1989.The conclusion of this Environmental Assessment is that the proposed action would result in no significant environmental impact.Based on a review of the information contained in this EA, the Districtdeterminedthat update of the Savannah River Basin Drought Contingency Plan of March 1989, would not constitute a major Federal action significantly affecting the quality of the human envITonment within the.meaning of Section 1 02(2)(c)ofNEPA.Accordingly, preparation of an Environmental Impact Statement is not required.A Finding of No Significant Impact will be released to announce this conclusion to the public, and afford them an opportunity to comment on the Proposed Action.59 DraftEA Drought Contingency Plan Update Savannah River Basin Table 31: Comparison of Effects of the No Action Alternative, Alternatives 1,2 and 3 May 2006 RESOURCE Water Quality Biotic Communities-Lakes, by observing the Pool Elevation Tables NO ACTION ALTERNATIVE No adverse impact Acceptable impacts, because the existing Drought Contingency Plan would be used, 3 violations of the 6" April 1-28 pool lowering rule were observed.ALTERNATIVE 1 Minor positive impact for the Augusta, Millhaven and Clyo gaging stations No adverse impact, 2 violations of the 6" April 1-28 pool lowering rule were observed.Minor positive impact for the Augusta, Millhaven and Clyo gaging stations Minor adverse impact, 5 violations of the 6" April 1-28 pool lowering rule were observed.ALTERNATIVE 3 Minor positive impact for the Augusta, Millhaven and Clyo gaging stations Minor adverse impact, 5 violations of the 6" April 1-28 pool lowering rule were observed.0\o Biotic Communities-Shoals Acceptable impacts-by downstream hydrographs Minor positive impact as flows.consistently 200 cfs higher than those of the No Action Alternative.

Minor positive impact as flows consistently 200-400 cfs higher than those of the No Action Alternative.

Minor positive impact as flows consistently 200-400 cfs higher than those of the No Action Alternative.-byEFM Biotic Floodplain (Lower flows recommended here)No adverse impact Minor positive impacts for each of the four model runs.Minor positive impacts for each Minor positive impacts for of the four model runs.three model runs and no impact for the fourth.For 2003 Workshop recommendation-by downstream hydrographs Minor adverse impact as flows'Minor adverse impact as flows are often 200-900 cfs higher are often 100-1000 cfs higher than the No Action Alternative.

than the No Action Alternative.

Reducing flows to the levels Reducing flows to the levels recommended in the Scientific

.recommended in the Scientific Stakeholders Workshop of April Stakeholders Workshop of 2003 would produce adverse", April 2003 would produce impacts for other Savannah.adverse impacts for other River resources.:

Savannah River resources.

The Dowmstream Hydrograph is very similar to that of Alternative 2 at left, so a minor adverse impact would result.

DraftEA Drought Contingency Plan Update Savannah River Basin Table 31: Comparison of Effects of the No Action Alternative, Alternatives 1,2 and 3 (continued)

May 2006 RESOURCE NO ACTION ALTERNATIVE 1 i!ALTERNATIVE 2 AT LVE ALTERNATIVE

...,"'...'....'For 10,000 stream cfs No adverse impact as flows are No adverse impact as flows are The Dowmstream Hydrograph channel capacity rarely above 9000 cfs during the rarely above 9000 cfs during is very similar to that of-by downstream hydrographs drought.Coordination of the drought.Coordination of Alternative 2 at left, so no Thunnond releases would be Thunnond releases would be adverse impact would result.required to achieve seedling required to achieve seedling establishment.

, establishment.

Biotic Communities-Estuary Acceptable impacts-by downstream hydrographs Minor positive impact as flows Minor positive impact as flows Minor positive impact as flows are 200-1000 cfs higher than the are higher for longer than those are higher for longer than those No Action Alternative for of the No Action Alternative.

of the No Action Alternative.

December 2000 through November 2002.,-byEFM Minor positive impacts.Minor positive impacts Minor positive impacts Threatened and Endangered Acceptable impacts Species-by downstream hydrographs Minor positive impact with a Minor positive impact with a Minor positive impact with a predominant 200 cfs flow predominant 200-400 cfs flow predominant 200-400 cfs flow increase.mcrease increase.-byEFM Minor positive impacts.Minor positive impacts.Minor positive impacts for three model runs and no adverse impact for the fourth.Recreation, Boat-Launching Hartwell: Minor Adverse Hartwell: Positive Hartwell: Positive Ramps and Docks RBR: No Adverse RBR: No Adverse RBR: No Adverse JST: Minor Adverse'JST: Positive JST: Positive Recreation, Swimming Hartwell: No Adverse Hartwell: Minor Positive Hartwell: Minor Positive RBR: Not Applicable

, RBR: Not Applicable JST: No RBR: Not Applicable JST: No Adverse.Adverse JST: No Adverse DraftEA Drought Contingency Plan Update Savannah River Basin Table 31: Comparison of Effects of the No Action Alternative, Alternatives 1, 2 and 3 (continued)

May 2006 RESOURCE NO ACTION ALTERNATIVE 1 ALTERNATIVE 2 ALTERNATIVE 3 ALTERNATIVE

.....Water Supply Hartwell: No Adverse Hartwell: No Adverse Hartwell: No Adverse RBR: No Adverse RBR: No Adverse RBR: No Adverse JST: No Adverse JST: No Adverse JST: No Adverse Below JST Augusta: Positive Below JST Augusta: Positive Below JST Augusta: Positive Hydropower Positive No Adverse Minor Adverse Cultural Resources No additional adverse No additional adverse impacts No additional adverse impacts No additional adverse impacts impacts Environmental Justice No adverse impact No disproportionately high and.No disproportionately high and No disproportionately high and adverse impacts.adverse impacts.adverse impacts.

DraftEA Drought Contingency Plan Update Savannah River Basin Table 32: Comparison of Pool Elevations and Actions Taken for the NAA, Alternatives 1, 2 and 3 May 2006 Break Point Elevations NO ACTION ALTERNATIVE ALTERNATIVES 1-3 Level Hartwell 18 Apr-15 Oct Hartwell 01 Dec-Ol'Jan HartweU01Apr-150ct Hartwell 15 Dec-01Jan Thurmond 01 MaY"15 Oct Thurmond 15 Dec-01 Jan Thurmond 01Apr-15 Oct*Thurmond 15 Dec-01Jan 1 656&326 655&325 656&326 654&324 2 654&324 652&322 654&324 652&322'.3 646&316 646&316 646&316 646&316 4 625&312 625&312 625&312 625&312 Actions Taken at Tri22er Levels Level NAA ALTERNATIVE!

ALTERNATIVE 2 ALTERNATIVE 3 1 Safety Advisory Safety Advisory Max Weekly Average 4200 cfs at Max Weekly Average 4200 cfs JST atJST 2 Max Weekly Max Weekly Average Max Weekly Average Max Weekly Average Average 4500 cfs at JST 4000 cfs at JST 4000 cfs at JST 4500 cfs at JST 3 Specified Daily Specified Daily Flow Specified Daily Flow Specified Daily Flow Flow 3800 cfs at JST.3800 cfs at JST 3600 cfs at JST 3600 cfs at JST Above Minimum Daily Minimum Daily Average Flow Minimum Daily Average Flow Minimum Daily Average Flow Level 4 Average Flow 3600 cfs at JST 3800 cfs at JST 3800 cfs at JST (except LV3)3600 cfs 4 Outflow=Inflow Outflow=Inflow Outflow=Inflow Outflow Inflow DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 6.0 RELATIONSIDP OF PROJECT TO FEDERAL AND STATE AUTHORITIES The following table summarizes the status ofthe compliarICe of the proposed action (Alternative 2)with applicable Federal and State environmental laws.Table 33: Relationship of Plans to Environmental Requirements POLICIES PROPOSED ACTION Anadromous Fish Conservation Act, 16 U.S.C.Partial compliance.

Draft EA will be 757, et.seq.coordinated with NMFS.Archaeological and Historic Preservation Act, a.Partial compliance.

District's determination of amended, 16 U.S.C.469, et.seq.no effect will be coordinated with he SHPO in both GA and SC.Clean Air Act, as amended, 42 U.S.C.1857h-7, Partial compliance.

Draft EA will be et.seq.coordinated with EPA.Clean Water Act, as amended (Federal Water Partial compliance.

District will coordinate Pollution Control Act)33 U.S.C.1251, et.seq.Draft EA with both GA and SC.Coastal Zone Management Act, as amended, 16 In compliance.

...U.S.C.1451 et seq.Endangered Species Act, as amended, 16 U.S.C.Partial compliance.

District's determination of 1531, et.seq.no effect will be coordinated with the USFWS andNMFS.Federal Water Project Recreation Act, as In compliance.

amended, 16 U.S.C.4601-12, et.seq.Fish andWildlifeCoordination Act, as amended In compliance.

Draft EA will be coordinated 16 U.S.C.661, et.seq., with the GA and SC DNR, as well as the USFWS and NMFS.Fishery Conservation and Management Act of In compliance.

1976, Public Law 99-659.Magnuson-Stevens Act, as amended, Public LaVl Partial compliance.

District will coordinate 104-297.determination with NMFS.National Historic Preservation Act of 1966, as Partial compliance.

District's determination of amended, 16 U.S.C.470f, et seq.no effect will be coordinated with the SHPO in both GA and SC.Protection of Wetlands, E.O.11990 In compliance.

Environmental Justice, E.O.12898 In compliance.

7.0 COORDINATION

Savannah District has coordinated with Federal and state officials on a regular basis during the course of the Savannah River Basin Comprehensive Study that includes this proposed change in the Savannah River Basin Drought Contingency Plan of 1989.This coordination was enhanced by the meeting of the Scientific Stakeholders Workshop of 1-3 April 2003 where recommended 64 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Savannah River flows were discussed for the Augusta shoals, floodplain and estuary.The coordination has continued with several stakeholder meetings in the Augusta area.The meetings have aided the Corps as it attempts to balance the various needs that include hydropower, recreation, water supply, water quality and wildlife management.

A Public Notice of Availabilty was issued on 24 May 2006 notifying the public of the availability of the Draft EA.This Notice served as the formal advertisement of the update.Agencies, individuals and organizations that have expressed an interest in the update were furnished a copy of the EA 8.0 LITERATURE CONSULTED Applied Technology and Management, 1998.Savannah Harbor expansion Environmental Impact Statement.

Georgia Ports Authority.

Savannah, Georgia.244 pp.Cooney, T.W., K.H.Jones, P.A.Drews, S.W.Ellisor and B.W.Church, 1998.Water Resources Data for South Carolina-Water Year 1998.US Geological Survey Report SC-98-1.Columbia,South Carolina.546 pp.Draft" Fish and Wildlife Coordination Act Report on the Savannah River Basin Comprehensive Study, US Fish and Wildlife Service, October 2003.Ecosystem Flow Recommendations for the Savannah River below Thurmond Dam, Final Report from April 1-3, 2003, Scientific Stakeholders Workshop, September 2003.Ecosystem Functions Model Users Manual, US Army Corps of Engineers, Hydrologic Engineering Center, August 2002.Lake Regulation and Coordination for Fish Management Purposes, South Atlantic Division, US Army Corps of Engineers, 30 March 2001.McBay, L.G., 1968.Location of Sexually Mature Striped Bass.GA Game and Fish Comm.Coastal Region Fish Invest.Report.Job II-l:27-48.

Odum, W.E., T.J.Smith III, 1.K.Hoover, and C.C.McIvor, 1984.The Ecology of Tidal Freshwater Marshes of the United States East Coast: a Community Profile.US Fish and Wildlife Service.FWS/OBS-83/17.

Pearlstine, L., W.Kitchens, P.Lathem, and R.Bartleston, 1990.Application ofa Habitat Succession Model for the Wetlands Complex of the Savannah National Wildlife Refuge.Florida Cooperative Fish and Wildlife Research Unit, University of Florida, Gainesville.

Reconnaissance Planning Aid Report on the Savannah River Basin Study, US Fish and Wildlife Service, July 1999.65 DraftEA Drought Contingency Plan Update Savannah River Basin May 2006 Rees, R.A.1974.Statewide Fish.Invest.GA.Game and Fish Div.Final Rept.Fed.Aid Proj.F-21-5 study 14 job 1.11 pp.Robbins, C.S., D.K.Dawson, and B.A.Dowell, 1989.Habitat Area Requirements of Breeding Forest Birds ofthe Middle Atlantic States.Wildlife Monograph No.103.34 pp.Savannah River Basin Drought Contingency Plan, US Army Corps of Engineers, Savannah District, March 1989.Schmitt, D.N.and J.H.Hornsby, 1985.A fisheries Survey ofthe Savannah River.Georgia Department of Natural Resources Final Report for Project Number F-30-12.Atlanta, Georgia.91 pp.Summary Report Supporting the Development of Ecosystem Flow Recommendations for the Savannah River below Thurmond Dam, June 2003.University of Georgia Team.Teal, 1.M.1962.Energy Flow in the Salt Marsh Ecosystem of Georgia.Ecology, 43(4): 614-624.VanDen Avyle, M., M.Maynard, R:-Klinger, afld V'Blaier;1990.Effects of Savannah Hai:'hor Development on Fishery Resources Associated with the Savannah National Wildlife Refuge, Georgia Cooperative Fish and Wildlife Research Unit, University of Georgia, Athens.Winger, P.V.and P.J.Lasier, 1990.Effects of Salinity on Striped Bass Eggs and Larvae.US Fish and Wildlife Service, National Fisheries Contaminant Research Center, University of Georgia, Athens.Report submitted to US Army Corps of Engineers, Savannah District.66