Current Water Management Practices for Kerr Reservoir

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1 Current Water Management Practices for Kerr Reservoir Ashley Hatchell Water Management Lake Gaston Association Monthly Meeting 03 February 2016 US Army Corps of Engineers

2 Outline and Goals for Today s Presentation Corps will explain the Corps operation of Kerr Project purposes and operational considerations Relationship with Dominion and Lake Gaston/Roanoke Rapids Dominion will explain Dominion s operation of Gaston and Roanoke Rapids Operational considerations and FERC License requirements Corps will explain the proposed revision to flood operations at Kerr, called Quasi Run of River or QRR Why the proposed change What it will mean for the basin What can Lake Gaston expect Questions

3 Roanoke River Basin The Roanoke travels ~400 miles from the mountains to the sound Drainage area ~9600 square miles 3

4 John H Kerr Multi-Purpose Reservoir Flood Risk Management temporarily stores flood waters for release at non-damaging or less-damaging rates. Hydroelectric Power provides reliable, economical power to municipal and industrial customers in Virginia and Carolinas. Recreation provides excellent recreational opportunities. Water Supply valuable regional water supply for municipal and industrial water users. Low Flow Augmentation minimum releases now met by Roanoke Rapids per its FERC license Fish and Wildlife provides additional flow for striped bass during spawning season

5 Water Management Goals Maximize congressionally authorized purposes within existing operational guidelines Predictable responses to varying conditions Actively inform affected stakeholders

6 Cross-Section of John H Kerr Dam Reservoir Storages Controlled Flood Storage 300 to 320 = 1,281,400 Ac-Ft Power Storage 268 to 300 = 1,027,000 Ac-Ft Sediment Storage 200 to 268 = 461,600 Ac-Ft

7 John H Kerr Reservoir Operational Guide Curve 7

8 John H Kerr Hydropower Operations Weekly Energy Declaration Prepared each Wed for the following Sat to Fri Based on: starting and desired ending lake level guide curve anticipated inflows (but not forecast rainfall) SEPA minimum energy commitments outflows (flood ops, spawning) revised as needed if additional rainfall

9 John H Kerr Spawning Releases Fish Flows for Striped Bass Spawning Memorandum of Understanding with NC Wildlife Resources Commission Period Flow Range (cfs) Target Apr ,600-13,700 8,500 Apr ,800-11,000 7,800 May ,700-9,500 6,500 May ,400-9,500 5,900 Jun ,000-9,500 5,300 Need attracting flows After spawn, need flows adequate for transport to downstream nursery areas

10 Spawning Storage/Releases

11 John H Kerr Operations for Flood Risk Management 11

12 Recent Flood Operations at Kerr 13 of 18 weeks since 01 October in Flood Operations 12

13 Recent Flood Operations at Kerr 13

14 Summary of Key Points Corps issues weekly declaration from Kerr. Dominion schedules hourly releases from Gaston-Rapids AND Kerr. Corps declares flood operations, which allows operational changes at Gaston and Rapids. Dominion can operate Gaston to elevation 203 ft when the Corps declares flood operations. (up to 201 ft during the spawn) Turbine capacities are approximately: 40,000 cfs at Kerr; 44,000 cfs at Gaston; 20,000 cfs at Rapids The Corps does not declare more releases from Kerr than needed to maintain Corps-directed flood or spawning releases from Roanoke Rapids. 14

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16 Contact Information: Ashley Hatchell Water Management Corps of Engineers, Wilmington District 69 Darlington Avenue Wilmington, NC (910)

17 Proposed Water Control Plan Update Proposed modification of flood operations Quasi Run-of-River Operation QRR Why modify existing flood operations? What does QRR look like?

18 Proposed Water Control Plan Update - QRR Why modify existing flood operations? Existing food operation results in protracted flood releases. These releases inundate the floodplain ecosystems of the lower Roanoke River. Protracted inundation of the floodplain downstream of Roanoke Rapids Dam is adversely altering / stressing the floodplain forest ecosystem. Instead of seeing the natural rise and fall of the river through these ecosystems, the floodplains now see essentially a steady wall of water

19 Proposed Water Control Plan Update - QRR

20 Comparison of Existing and QRR Flood Operations Actual Roanoke Rapids Releases (cfs) 5000 QRR Roanoke Rapids Releases (cfs) 0 Elev (ft-msl) 1-Sep 5-Sep 9-Sep 13-Sep 17-Sep 21-Sep 25-Sep 29-Sep 3-Oct 7-Oct 11-Oct 15-Oct 19-Oct 23-Oct 27-Oct 31-Oct 4-Nov 8-Nov 12-Nov 16-Nov 20-Nov 24-Nov 28-Nov 2-Dec 6-Dec 10-Dec 14-Dec 18-Dec 22-Dec 26-Dec 30-Dec 3-Jan 7-Jan 11-Jan 15-Jan 19-Jan 23-Jan 27-Jan 31-Jan 4-Feb 8-Feb 12-Feb 16-Feb 20-Feb 24-Feb 28-Feb 3-Mar 7-Mar 11-Mar 15-Mar 19-Mar 23-Mar 27-Mar 31-Mar 7-day average Release (cfs)

21 Proposed Water Control Plan Update - QRR What should Lake Gaston expect to see differently under QRR? Less weeks under Corps-declared flood operations means less time when allowed operation above 200 ft. Why should Gaston property owners not expect higher lake levels more often? Corps will still issue a weekly declaration at Kerr; and Dominion will still schedule releases from Kerr, Gaston and Rapids to make efficient use of the resource to meet customer demands, while maintaining the necessary balance in lake elevations at Gaston and Rapids. Corps will still consider local inflows and not declare more water out of Kerr than may be requested from Rapids (for flood ops or spawn period). Corps and Dominion will still maintain coordination among operations. The full range of releases (up to 35k) are less than turbine capacity at Gaston. You see 35k from Kerr under normal daily peaking operations. (plot) You ve seen extended 35k before most recently, April (plots)

22 40000 KERR HOURLY OUTFLOW (CFS) RAPIDS DAILY OUTFLOW (CFS) 15 BUGGS ISLAND MAX STAGE (FT) GASTON MIDNIGHT ELEVATION (FT-MSL) 2003 flood ops sustained ~35k release 2015 normal ops BUILDING with ~35k STRONG peaking

23 QUESTIONS