Lake Mead vs Lake Powell
The two largest US reservoirs, side by side - updated daily from Bureau of Reclamation gauges.
Western Reservoir Conditions·Daily·No. 51··Latest reading
- As of , Lake Mead is 26.4% full (1,038.65 ft, 6,885,040 acre-feet) and Lake Powell is 21.9% full (3,517.13 ft, 5,102,800 acre-feet). Lake Mead holds the higher share of its capacity today.
- Together the two hold 11.99 million acre-feet - 24.3% of their combined 49.43 million acre-foot capacity. They are the two largest reservoirs in the United States by capacity: Mead first at 26.12 million acre-feet, Powell second at 23.31 million.
- Over the past year Lake Mead's surface has moved -17.89 ft and Lake Powell's -29.49 ft. Elevations are not comparable across the two lakes (different canyons, different datums) - percent full and storage are.
One river, two buckets, two jobs: Powell (upstream, behind Glen Canyon Dam) stores Upper Basin runoff and meters it down through the Grand Canyon; Mead (downstream, behind Hoover Dam) turns that inflow into scheduled deliveries for Arizona, Nevada, California, and Mexico. Reading them together is how the Colorado River's condition is actually judged.
Side by side, September 11, 2026
| Lake Mead | Lake Powell | |
|---|---|---|
| Percent full | 26.4% | 21.9% |
| Status | Very low | Very low |
| Elevation | 1,038.65 ft | 3,517.13 ft |
| Storage | 6,885,040 AF | 5,102,800 AF |
| Capacity basis | 26,120,000 AF | 23,314,000 AF |
| Full pool | 1,219.6 ft | 3,700.0 ft |
| 1-year change | -17.89 ft | -29.49 ft |
| Record low | 1,038.65 ft (September 11, 2026) | 3,517.13 ft (September 11, 2026) |
| Dam | Hoover Dam (1935) | Glen Canyon Dam (1963) |
| Downstream obligation | Deliveries to AZ, NV, CA & Mexico | Annual release target to Lake Mead |
Percent full, past five years
The two lines move on different logic. Powell responds first to each winter's snowpack - it takes the runoff - while Mead's line is dominated by the balance between Powell's releases and downstream deliveries, so it moves later and more smoothly. The sharp 2023 rise in both followed that winter's exceptionally large snowpack.
More context: the seven-reservoir system page · Lake Mead record-low tracker · USBR 24-Month Study projections · CSVs: Mead, Powell.