Lake Powell — the reservoir behind Glen Canyon Dam on the Arizona–Utah border — is one of the most-watched water bodies in the American West. For two decades the headline has been the same: the water keeps dropping. Here is why, in plain numbers.
The short answer
Lake Powell is low for two reinforcing reasons. First, the Colorado River basin has been gripped by the driest 20-plus-year stretch in roughly 1,200 years, so far less water flows in than the 20th-century average. Second, the river is over-allocated: the basin has long used more water than the river reliably delivers. Less supply meeting steady demand is a recipe for a shrinking reservoir.
How low is Lake Powell right now?
At full pool, Lake Powell sits at elevation 3,700 feet and stores about 24.3 million acre-feet (MAF) of water. Its all-time high was 3,708.34 feet in July 1983. The modern record low came on April 13, 2023, at 3,519.92 feet — roughly 150 feet below full and only about 150 feet above the point where the dam stops functioning normally.
The live figures above show where the lake stands today and how it has moved over the last 30 days. For the full year of daily readings and the record high and low, see the water level chart.
Why the reservoir dropped: three forces
1. A megadrought, not just a dry spell
Tree-ring reconstructions published in Nature Climate Change (Williams et al., 2022) found that 2000–2021 was the driest 22-year period in the Southwest in about 1,200 years — and that human-caused warming made it substantially worse. Hotter air pulls more moisture from soil and snow, so even average snowfall produces below-average runoff into the reservoir.
2. The Colorado River is over-allocated
The 1922 Colorado River Compact divided the river’s water assuming an annual flow that later proved optimistic. Roughly 40 million people and millions of acres of farmland now depend on the river. When the paper promises exceed the water actually in the channel, reservoirs like Powell and Mead absorb the shortfall — and shrink.
3. Steady releases to the Lower Basin
Glen Canyon Dam doesn’t just hold water; it releases it downstream to Lake Mead to meet Upper Basin delivery obligations and to generate hydropower. In dry years those releases can exceed what flows in, drawing the reservoir down further.
Lake Powell vs. Lake Mead
Powell and Mead are the two giants of the Colorado River system and they rise and fall together. The evergreen basics:
| Lake Powell | Lake Mead | |
|---|---|---|
| Dam | Glen Canyon (completed 1963) | Hoover (completed 1936) |
| Full-pool elevation | 3,700 ft | 1,229 ft |
| Capacity at full pool | ~24.3 MAF | ~26 MAF |
| Basin role | Upper Basin “savings account” | Lower Basin delivery hub |
For a live, side-by-side look at how full each reservoir is today, see Lake Powell vs. Lake Mead.
How close is it to “dead pool”?
Two elevations matter most on the way down:
- Minimum power pool — 3,490 feet. Below this, Glen Canyon Dam can no longer reliably generate hydroelectricity.
- Dead pool — 3,370 feet. Below this, water can no longer pass through the dam’s outlets by gravity at all.
The dead pool tracker shows exactly how many feet of cushion remain today. The reservoir has never reached either threshold, but the 2022–2023 scare pushed the water uncomfortably close to the power-pool line.
So — is it rising or falling?
Both, on a schedule. Lake Powell almost always rises in late spring and early summer as mountain snowpack melts, then falls through late summer, fall, and winter. A single strong snow year can add dozens of feet: the exceptional 2023 snowpack lifted Powell roughly 50 feet off its April 2023 record low. Whether those gains hold depends on the next winter — which is the subject of Will Lake Powell fill back up?
For today’s direction, watch the live callout above and the forecast page.
Sources
- Williams, Cook & Smerdon, “Rapid intensification of the emerging southwestern North American megadrought,” Nature Climate Change (2022)
- U.S. Bureau of Reclamation — Glen Canyon Dam / Lake Powell operations
- Reclamation Upper Colorado Region — daily reservoir elevation data (the live figures on this page)
- National Park Service — Glen Canyon NRA, Changing Lake Levels