Lake Powell is about to get a boost. How much will it help?

Spring represents a fresh start for plants, animals, alarm clocks — and Lake Powell.

Lake Powell’s levels have fallen throughout the winter, but as the weather warms, the snowpack that has accumulated in the mountains over the winter will begin to melt. That water will feed rivers and streams across the West — including the Colorado River, which fills Lake Powell on Arizona and Utah’s shared border.

This year, hydrologists forecast that Lake Powell’s peak capacity will rebound close to its peak capacity last year. But those elevations are still far below 100% full.

The National Weather Service Colorado Basin River Forecast Center predicts that 5.4 million acre-feet of unregulated runoff will spill into the reservoir between April and July. For reference, an acre-foot of water can sustain two households for a year.

The reservoir’s level is expected to rise from its current level, 32% full, to 37% full capacity at its projected peak. That’s a jump from an elevation of 3,560 feet right now to about 3,581 feet — an increase of 21 feet.

The lake’s elevation at full capacity is 3,700 feet.

Last year, after a record-breaking winter, Lake Powell rose from a record low of 22% full to 38% full — a rise from about 3,522 feet in elevation to 3,583 feet. The reservoir’s elevation is up almost 39 feet from where it was last March.

The Colorado Basin River Forecast Center provides runoff projections to the Bureau of Reclamation, a federal agency that oversees water projects nationwide. A March 2024 report from the Bureau of Reclamation forecasting water storage and reservoir levels for the next two years predicts that Lake Powell will receive 7.66 million acre-feet of water between October 2023 and September 2024.

In October 2023, Reclamation predicted that Lake Powell would receive 9.4 million acre-feet over the same time frame. After a dry start to the winter, the agency revised its estimate in December to be 7.6 million acre-feet.

According to the Colorado Basin River Forecast Center, spring runoff this year will be 85% of the average runoff between 1991 and 2020.

Since the turn of the century, the Colorado River’s flows have decreased by at least 20% due to climate change and extreme drought in the West. As the river dwindles, U.S. states that rely on it are working to develop new plans to operate the river and its reservoirs, like Lake Powell.