Navajo Reservoir Operations CRFS Technical Committee November 16

Navajo Reservoir Operations CRFS Technical Committee November 16, 2010 Fall Technical Meeting

San Juan River Critical Habitat Gaging Stations

Chasing the Target Baseflow • Base releases remained at 500 cfs until June 24 th • Tributary inflow + Navajo Releases keep the river within Target Base Flow range • Increased release to 850 cfs on June 24 th, up to 1100 cfs on July 16 th • Release returned to 500 cfs on October 19 th, and should remain unchanged until next spring

Navajo Current Conditions (as of 11/9/2010) Elevation = 6063. 2 (102% of Average) Storage = 1, 388, 376 af (82% Full) Inflow = 250 cfs Release = 500 cfs NIIP = Not Diverting San Juan-Chama Diversion = Not Diverting

Update SNOTEL!!!

2011 Forecasted April-July Inflow & Spring Peak Release Most Probable (50% Ex. ) - 685, 000 af (91% of Avg) Peak Release = 172, 000 af (2 weeks@ 5000 cfs) Minimum Probable (90% Ex. ) - 233, 170 af (31% of Avg) Peak Release = 118, 000 af (1 week@5000 cfs – if perturbation yr) Maximum Probable (10% Ex. ) - 1, 171, 470 af (155% Avg) Peak Release = 926, 000 af (Full Hydrograph+ – 73 days @ 5000 cfs, 33 days @ 4000 cfs) Peak Release centered over Animas at Farmington peak Base release of 500 cfs for remainder of water year (~362 K af)

Put Hydrographs and downstream flow projection data here from 2011 Navajo Release Scenarios

WY 2011 Estimated Inflows into Lake Powell from the San Juan (based on SJ @ Bluff modeled flows) Most Probable (50% Ex. ) - 1, 022, 000 acre-feet (73% of Average WY 1981 -2010) Minimum Probable (90% Ex. ) - 520, 000 acre-feet (37% of Average WY 1981 -2010) Maximum Probable (10% Ex. ) - 2, 845, 654 acre-feet (202% of Average WY 1981 -2010)

Western Colorado Area Office Contacts: Pat Page 970 -385 -6560, ppage@usbr. gov Ryan Christianson 970 -385 -6590, rchristianson@usbr. gov