Satellite images illustrate how water levels in Lake Mead have fallen in the past 25 years.
Why It Matters
Lake Mead supplies vital water to millions in Nevada, Arizona, California, and parts of Mexico. However, declining water levels could jeopardize city water systems, farm irrigation, and hydroelectric power output.
Lake Mead is the largest reservoir in the U.S., capable of storing approximately 29 million acre-feet of water. It is closely followed Lake Powell, with a capacity of around 25 million acre-feet.
Recent forecasts lowered runoff into Lake Powell to just 55 percent of average, down from an earlier estimate of 67 percent, due to an underwhelming winter snowpack.
Lake Mead, which receives flows from Lake Powell, hit critically low levels during the summer of 2022, following years of drought.
What To Know
Satellite imagery captured by Landsat 7, a joint mission of the United States Geological Survey (USGS) and NASA, show a stark contrast in Lake Mead’s water levels between July 1999 and May 2024, with the reservoir appearing noticeably smaller in the latter image.
Images provided to Newsweek by Maxar Technologies further highlight Lake Mead’s current levels compared to historical ones with the “bathtub ring” effect in display.
Colin Williams, a mineral resources program coordinator with the USGS, told Newsweek previously that this ring around the lake is the result of calcium carbonate found in the Colorado River water. As the lake’s water level fluctuates, these minerals cling to the surrounding rocks. When Lake Mead’s water level drops, calcium carbonate is left behind on the rocks, forming the visible bathtub ring.
“Lake Mead is full at 1,229 feet above sea level, so the bathtub ring disappears when the lake level is near that point,” Williams said at the time.
At the time of writing, Lake Mead’s water levels were 1,054.85 feet mean sea level, 174.15 feet below its full pool of 1,229, according to Lakes Online, an online resource for lake and reservoir information.
What People Are Saying
Sharon Megdal, Director of the University of Arizona Water Resources Research Center, told Newsweek: “This time period has been dominated by lower annual natural river flows than those of the prior century. In addition, deliveries to water users in the Lower Basin, coupled with 1944 Treaty deliveries to Mexico have exceeded inflows, causing significant decline in the amount of water in storage since 2000.
“Despite many interventions to prop up water levels in the reservoir, “Mother Nature’s flows have not been generous,” Megdal added.
What Happens Next
A recent study suggested that boosting wastewater recycling to 40 percent in the Colorado River Basin could conserve about 900,000 acre-feet of water annually—enough to supply nearly two million households.
Meanwhile, the states that depend on the Colorado River have been in talks to establish new water-sharing agreements by 2026.
The post Satellite Images Show How Much Lake Mead Has Shrunk in 25 Years appeared first on Newsweek.
