LAS VEGAS (KLAS) — The outlook for Lake Mead water levels as March begins gives reason for hope and reason for despair. Hope comes with above-average snowpacks in Colorado and Utah, and despair comes with a projected drop in water levels that will leave Lake Mead lower than it’s been since it initially filled in the 1930s.
The last time Lake Mead was as low as it is now was last year, before that it was in 1937. Lake Powell to the northeast is at its lowest point since it first filled in the late 1960s. Even further upriver, the Flaming Gorge Reservoir in Wyoming and Utah is showing another steep decline this year. And south of all this, at Lake Mohave and Lake Havasu, all is well.
It’s this system of dams and reservoirs that has helped to supply the southwest with reliable water for more than 85 years. Now, at the beginning of March, millions of people are watching and waiting nervously to see what will happen to water supplies as spring approaches, builders keep building and farmers prepare their fields for a busy growing season.
The latest projection from the U.S. Bureau of Reclamation, which manages the Colorado River basin, is that Lake Mead could drop close to 20 feet this year, which would put its level at the lowest since it was filled. But with an above-average snowpack in Colorado and Utah right now, hopes are that a slow spring melt will help reduce that projection.
For now, here is a look at the water levels of these five major reservoirs before the upper Colorado River basin traditionally sees an increase due to snowpack melt and the lower Colorado River basin reservoirs traditionally see a decline, mainly due to agriculture irrigation needs in southern California.
Flaming Gorge Reservoir
Flaming Gorge Reservoir is located along the Green River and straddles the border of southwest Wyoming and northeast Utah. The Green River eventually flows into the Colorado River within Canyonlands National Park in southeast Utah.
Currently, the Flaming Gorge Reservoir is at 6,005.85 feet above sea level (the measurement used throughout the river basin), which places it at approximately 68% of its storage capacity.
Its most recent decline began in mid-July of last year. Since then, the water level has dropped around 10 feet. This coincides with a Bureau of Reclamation plan we reported on Aug. 30, 2022, where an agreement was reached to release an additional 500 thousand acre-feet (kaf) of water from Flaming Gorge to Lake Powell through April 2023.
With Flaming Gorge releasing more water into Lake Powell, one might expect lake levels to be increasing. As of Thursday (March 2, 2023), the water level at Lake Powell continues to fall. But there appears to be a little bit of positive action happening because, for now, Lake Powell’s water level is not dropping as rapidly as it has this time in recent years.
Here in southern Nevada, Lake Mead’s water levels have been rising overall since the end of July. Lake Mead is now at 1,046.97 feet above sea level. This is 6.26 higher than last year’s record low level.
Last fall’s monsoon season and a wet winter locally have helped a little, but the largest factor determining the future of Lake Mead’s level is the snowpack in Colorado and Utah.
To the south of Lake Mead and the Hoover Dam is another reservoir on the Colorado River with water held back by the Davis Dam between Bullhead City, Arizona, and Laughlin.
Davis Dam was completed in 1951 which led to the filling of Lake Mohave. According to the National Park Service, “Construction of Davis Dam was a requirement of the 1944 Water Treaty with Mexico to regulate water released from Hoover Dam for delivery to Mexico.”
Lake Mohave is an outlier along the Colorado River basin’s system of reservoirs and dams because its water level has not dramatically changed in recent years.
Lake Mohave has a total storage capacity of 1,818,300 acre-ft, according to the National Park Service, and remains approximately 100 feet deep year-round. Because of its location, Lake Mohave is a holding reservoir that ensures consistent water can be supplied to Arizona and California year-round.
As seen in water level data from the last five years, Lake Mohave stays about the same level from March through August before a scheduled drawdown of about 7 feet for two months. It then begins to refill in November before starting the cycle over again.
Below Lake Mohave is the last of the large reservoirs, Lake Havasu, which is held back by the Parker Dam.
Much like the water level for Lake Mohave, Lake Havasu rarely drops or rises more than 3 feet, at least over the last five years.
Lake Havasu currently is 448.4 feet above sea level, which is actually more than 3 feet above its listed maximum height, also known as its full pool.