How Hilary Changed Lake Mead, Powell, California Reservoir Water Levels - Newsweek

How Hilary Changed Lake Mead, Powell, California Reservoir Water Levels

Despite an onslaught of rain from Tropical Storm Hilary, the reservoirs in the southwestern United States have not been massively affected.

The storm hit California on Sunday, where it caused flooding in major cities like Los Angeles and other areas. Seeing as the West has suffered from intense drought, many questioned whether the storm would help replenish the region's reservoirs, which have been declining in recent years.

The reservoir with the most water level change is Lake Mead, a Colorado River reservoir lying between Nevada and Arizona near the California border that has risen by a few inches.

Before the storm hit the region, Lake Mead's water levels stood at 1,063.49 feet. On August 20, water levels rose to 1,063.62 feet. On August 21, the second day of the storm, the lake's water levels were at 1,063.78 feet, rising to 1,064 feet the next day.

Lake Powell, Lake Mead's neighbor, does not appear to have been affected so far. In fact, the lake has seen a slight decline in recent days. As of Tuesday, its water level stands at 3,575.85 feet. Last month, it reached the highest point seen for three years, at 3,584 feet. But since that high point, it has declined gradually.

According to a map compiled by the California Department of Water Resources, California's reservoirs also do not appear very impacted. Most water levels have stayed the same or declined.

At the start of this year, however, all of these reservoirs were in a dire state. Lake Mead was at only about 30 percent of its usual capacity at 1,044 feet, while Lake Powell was at 3,524 feet. Lake Shasta, California's largest reservoir, was at 928 feet.

Climate change has meant that intense periods of drought, followed by intense rain, have become more commonplace. The southwest saw an intense wet period this past winter and early spring. Rain and snow storms battered the area, and in doing so, accumulated record levels of snowpack in the surrounding mountains.

As the spring came, this snowpack melted and replenished the region's reservoirs, meaning that even before Tropical Storm Hilary hit, the reservoirs were in a better state than they have been in years. In May, Lake Shasta was nearly at full capacity.

Experts remain poised to keep watch on the situation, as the reservoirs provide water to millions of people in the southwest. Lake Mead, in particular, provides water for around 25 million people in the Colorado River basin.