Aspinall Unit Reservoir Operations CRFS Meeting November 16, 2010

Aspinall Unit Reservoirs Blue Mesa Reservoir Morrow Point Reservoir Crystal Reservoir

Aspinall Reservoir Basics Blue Mesa 829,500 AF 2 – Power Units Max control release: 6,100 cfs Morrow Point 117,000 AF 2 – Power Units Max control release: 6,500 cfs Crystal 17,500 AF 1 – Power Units Max control release: 4,300 cfs Side Inflow Reservoir Release Reservoir Release Gunnison R. Inflow

Aspinall Unit Authorized Purposes Store water for beneficial uses Regulate the flow of the Colorado River Allow the Upper Basin states to use their apportioned water under the river compact Provide for flood control Generate Hydropower Provide for fish and wildlife enhancements and public recreation

Aspinall Unit Seasonal Operation Goals Blue Mesa Reservoir End of December target is ft Meet the Black Canyon Water Right peak flow during May Black Canyon of the Gunnison minimum flow is at least 300 cfs Black Canyon flows to be kept fairly steady outside of peak flow. Morrow Point and Crystal Reservoirs have drawdown rate restrictions (i.e. feet/day) Need to meet flood control needs of storing water in Blue Mesa Reservoir and to avoid flooding down river in the town of Delta. Adjust river flows for diversion needs through the Gunnison Diversion Tunnel. Meet all state water right needs on the river downstream. Adjust flows for trout spawning needs in the fall and spring months. Try to fill Blue Mesa Reservoir each year as much as possible. Operate for endangered fish species.

2010 Operations Review

2008 Apr-Jul Inflow 1.0 MAF (148 %) 2009 Apr-Jul Inflow 772 KAF (114 %) 2010 Apr-Jul Inflow 494 KAF (73 %)

3883 cfs May 1 Forecast 560 KAF Actual 24 HR Peak 4190 cfs on May 18

Blue Mesa Reservoir Water Year Unreg Inflow (1000 AF) Percent of Average 76% 32%63% 81%85%90% Each water year since 2002 has progressively been getting better; however this fall is shaping up to be very dry. Will it be another 2002, or just another below normal year?

Forecasted Inflows (Apr-July) January – 700 kaf February – 620 kaf March – 575 kaf April – 460 kaf Currently- 475 kaf Comparison Year Runoff Volume: 1989 – 443 kaf

Max Elev ft April 2007 Projection

Water Year 2010 Projected Operations

Water year 2011 we expect to meet the water right and fill blue Mesa