Kootenai Basin Spring/Summer Operations for 2016 Joel Fenolio, P.E. Upper Columbia Senior Water Manager Seattle District Julie Ammann, P.E. Chief Reservoir Control Center Northwest Division 24-27 May 2016
LIBBY DAM – THE BASICS Provides local and system flood control 11/10/2018 LIBBY DAM – THE BASICS Provides local and system flood control Local Bonners Ferry, ID – 1764 feet System is at The Dalles Max. flood control draft = 4.98 MAF (El. 2287 ft.) Full pool is El. 2459 ft. 11/10/2018
Libby Dam Apr-Aug May Inflow Forecast Corps forecast is 5.8 MAF (99% or average) 5.9 MAF is the average Apr-Aug inflow volume
Libby Dam WSF and Flood Risk Requirements
April 1 snowpack Near to above normal However … Atmospheric river intense, focused, steady rainfall with high snow levels Atmospheric river intense, focused, steady rainfall with high snow levels April 1 snowpack Near to above normal However …
April record warmth and dry Atmospheric river intense, focused, steady rainfall with high snow levels Atmospheric river intense, focused, steady rainfall with high snow levels Bonners Ferry: Warmest April on record Snowpack drops well below normal in a month With warmth, rapid snowmelt in April Now less snowmelt and with dry weather: Runoff decreases
Snowpack Story for 2016
BiOp Requirements and Habitat Operations Libby WSF of 5.8 MAF sets the following: Sturgeon Volume of 0.93 MAF As measured above 4 kcfs Bull Trout Minimum after the pulse through August 31st is 7 kcfs Habitat Operations 6 kcfs minimums in Sept Target 2449 ft end of August rather than end of Sept
Moderate ESP Inflow Scenario 2449 ft end of August Refill end of July Will be updated next week 9.2 kcfs flat flow 0.93 MAF Sturgeon Pulse
Dry Inflow Scenario Refill end of July Below 2449 ft end of August 7 kcfs flat flow 0.93 MAF Sturgeon Pulse
Probable Reservoir Elevations Full Pool 2,459 feet May 31 – 2,417 to 2,419 feet June 30 – 2,436 to 2,444 feet July 31 – 2,445 to 2,451 feet Aug 31 – 2,445 to 2,449 feet Elevations are highly dependent on rainfall for 2016. Only refilling to 2,440 ft is likely
Summary Timing of Inflows shifted up by 4 to 6 weeks Flood Risk low – based on the below average snowpack Libby Dam will likely not refill to 2452 to 2454 feet this summer Anticipated timing of refill late July to August Seattle District is currently looking at refilling earlier than late July June precipitation is the wild card in terms of flood risk and refill
Additional Slides
Snowpack 1-Feb 2012 and 2016 2012 2016
Snowpack 1-Mar 2012 and 2016 2012 2016
Snowpack 1-Apr 2012 and 2016 2012 2016
Snowpack 1-May 2012 and 2016 2012 2016