Grand Canyon Monitoring and Research Center

Lake Powell levels continue to drop as drought conditions persist. July 2003 mean elevation was 3610-3615 feet, while July 2004 levels are 3582-3586 feet, nearly 30 feet lower than 2003 levels. Spring and summer inflows to Lake Powell in 2004 have been 30% to 80% of normal (see links below for more information on basin hydrography).

As the lake surface drops, the reservoir's epilimnion (surface water) approaches the penstock withdrawal structures; but the possibility of warm surface water discharges can be offset by thinning of the epilimnion due to the drought.

Links:
The Bureau of Reclamation provides additional information about recent and projected Lake Powell elevations and inflow and outflow from Glen Canyon Dam at these website's:
http://www.usbr.gov/uc/water/crsp/glda.html

Most probably water supply gives projections for expected reservoir elevations and discharge/ inflow for the next 2 years are found here:
http://www.usbr.gov/uc/water/crsp/crsp_gc.txt
Minimum pool for next winter is projected to be below 3590 ft.