SOURCE: Los Angeles Times
DATE: July 11, 2021
SNIP: Lake Mead, a lifeline for 25 million people and millions of acres of farmland in California, Arizona, Nevada and Mexico, made history when it was engineered 85 years ago, capturing trillions of gallons of river water and ushering in the growth of the modern West.
But after years of an unrelenting drought that has quickly accelerated amid record temperatures and lower snowpack melt, the lake is set to mark another, more dire turning point. Next month, the federal government expects to declare its first-ever shortage on the lake, triggering cuts to water delivered to Arizona, Nevada and Mexico on Jan. 1. If the lake, currently at 1,068 feet, drops 28 more feet by next year, the spigot of water to California will start to tighten in 2023.
The crisis, said Eric Kuhn, former general manager of the Colorado River Conservation District, can no longer be ignored. “According to Merriam-Webster, a drought is a temporary condition,” he said. What is happening, he suggested, is something more permanent and troubling. “This is aridification.”
As fires sweep over large swaths of the West and scorching temperatures fry others, the scarcity of water is a less visible but perhaps the most pressing consequence of climate change confronting the states that depend on Lake Mead.
Lake Mead and the Colorado River are created from melted snow that flows into La Poudre Pass in the Rocky Mountains. Seven Western states — California, Wyoming, Colorado, New Mexico, Utah, Nevada and Arizona — as well as 29 tribes and Mexico depend on the water from the river. Each has signed successive treaties stating how much they receive from the river and dams, with the current agreements expiring in 2025.
Concerns over Lake Mead’s water levels came as negotiators met in Denver last month to take a preliminary step toward a four-year process to update operating rules and allocations for the reservoirs along the river.
According to the U.S. Bureau of Reclamation, which manages the river system, drought in Lake Mead is far from an emergency. Yet, the water level is nowhere near what it was a year ago. Having dropped 1.4 million acre-feet from April 2020 to April 2021 and 886,000 acre-feet since then, Lake Mead’s losses show no sign of slowing down.
But to many experts, it’s a make-or-break moment in the history of a river that has been for decades over-allocated, with less water available than is needed. What’s at stake for Lake Mead is a recreation area that draws more than 8 million visitors a year and generates $336 million annually.
While computer modeling helps water managers anticipate future shortages that could affect water supply and tourism, there is a gap in the understanding, said Kuhn, the former head of the Colorado River Conservation District. Predicting increased temperatures is easy — over the last century the West has heated up by nearly 2 degrees — but understanding how high temperature affects precipitation is less certain.
The monsoon rains that typically hit the Southwest during the summer never materialized last year. In Colorado, drier soil from higher-than-typical temperatures and lower air moisture has led to less melted snow draining into rivers and streams. As a result of the drought in Northern California, Los Angeles’ Metropolitan Water District is drawing down its reserves with water taken from the Colorado River, which will continue to flow uninterrupted through 2022.
But what comes next?