How the Colorado River’s new cuts will affect states, residents


Washington — Residents of Arizona and Nevada will not face restrictions on watering their lawns or washing their cars, despite the greater Colorado River water shortage.

But US officials announced Tuesday that the river that serves 40 million people in the West will have less water available to them next year. Mexico and the billion-dollar agricultural industry. Observers warn that a calculation for the growing area is still coming as future cuts are expected from the water crisis.

A look at the critical water sources and water cuts for the western US.

Why is the Colorado River at risk?

There are two Colorado rivers in the US—the 1,450-mile (2,334-kilometer) powerhouse to the west and the more than 800-mile (1,287-kilometer) river that begins and ends in Texas.

The river facing the cut is longer. It supplies seven states as well as Mexico, but its flow has decreased significantly over time because of farming and growing populations, warmer temperatures, evaporation, and less melting ice water in the spring to refill the river. Due to overuse, its flow has reduced considerably.

And over the years, the seven states that have received river water have diverted more water from it than is replenished by nature.

Who Serves Mead Lake and Powell Lake?

Lake Mead supplies water to millions of people in Arizona, California, Nevada and Mexico.

Reductions for 2023 begin when the projected water level falls below a certain threshold – 1,050 feet (320 m) above sea level.

Additional cuts will begin when the projected levels fall to between 1,045 and 1,025 feet (319 and 312 m). At a certain point, the level may drop so low that water can no longer be pumped out of the reservoir.

Eventually, some cities and industrial water users will be affected.

The level of Lake Powell is also falling and extraordinary steps have been taken to keep water in the reservoir at the Arizona-Utah border.

Colorado, New Mexico, Utah and Wyoming get their water from tributaries and other reservoirs that drain into Lake Powell. Water has been drawn from three reservoirs in those states in recent years to maintain the water level in Lake Powell and protect the electrical grid operated by Glen Canyon Dam.

What is being cut and why?

The federal government has begun cutting supplies to some states this year to maintain water levels in the river and its major reservoirs. Those cuts would build on new water cuts—which ended some central Arizona farmers’ supplies of the Colorado River’s water and, to a much lesser extent, reduced portions of Nevada and Mexico.

Lakes Mead and Lake Powell – the Colorado River’s two largest reservoirs – are about a quarter full, threatening water supplies and generating hydroelectric power that provides electricity to millions of people.

Along the banks of the reservoir, “bathtub rings” of minerals outline the site where the high water line once stood, highlighting the challenges facing the west known as the ‘megadrought’, leading to this region. But the grip is strong.

How is the river shared?

Colorado, Wyoming, Utah and New Mexico share the Colorado River in the upper basin of the river. Arizona, Nevada and California make up the lower basin.

From its headwaters in Colorado, the river and its tributaries eventually flow south of the border into Mexico, which also uses its waters. The river’s waters traditionally flowed through Mexico and reached the Gulf of California, but now rarely because so much is used by farms and cities. Among those who depend on the water are about 30 federally recognized Native American tribes.

To the southwest, the water stored in Lake Mead and Lake Powell—the two largest man-made reservoirs in the U.S.—is divided through legal agreements between Colorado River Basin states, the federal government, Mexico, and tribes. The agreements stipulate how much water each unit receives, when the cuts are triggered and the order in which the parties must sacrifice some of their supplies.

Under the 2019 Drought Contingency Plan, Arizona, Nevada, California and Mexico agreed to release part of their waters to maintain water levels in Lake Mead. This year’s cuts are part of that same plan — and as a result, state officials knew they were coming.

Which parties will be affected by the cut?

Arizona, Nevada and Mexico.

Arizona was again the hardest hit, and would receive 79% of its total next year. But it’s only 3% less than this year, after federal officials cut its supply.

Nevada will receive about 92% of its total supply next year. Most residents will not feel the cut because of water conservation, reuse and the state not using its full allocation.

California has been spared because it has more senior water rights than Arizona and Nevada. That means it doesn’t have to release its water first according to the hierarchy that guides water law in the American West.

Mexico will get about 93 percent of its total supply. The water is used in cities and farming communities in northwestern Mexico, which is facing severe drought.

Who will lose the water?

Farmers in central Arizona, one of the state’s largest producers of livestock, dairy, alfalfa, wheat and barley, lost much of the Colorado River allocation this year when the government implemented its first reduction. Some farmers were compensated by water through deals with cities such as Phoenix and Tucson.

More farmers will need to leave their land fallow – paid for by state agencies and others to some farmers in the region – and rely even more on groundwater. Others will be forced to grow more water-efficient crops such as durum wheat and gyule and to find other ways to use less water.

Western water suppliers plan for such reduction by diversifying and conserving their water sources. But accelerating drought depleting reservoirs faster than scientists predicted – and the resulting reductions – will make it harder for farms and cities to plan for the future.

“Most people aren’t even prepared for the kind of tough choices we need to make,” said Mark Squillus, a professor of environmental law at the University of Colorado. “And that’s the kind of situation we’re facing in the Colorado River.”

City water resources management consultant Cynthia Campbell said Phoenix would lose some water, otherwise it would be stored as water reserves in an underground basin. This happened this year also. The city will rely on more water from Arizona’s Salt and Verde rivers.

Campbell said Phoenix residents and businesses will not be affected. The city that was a sleepy desert community in the 1950s is now the 5th largest city in the country.

Nevada will also face cuts, but residents will not face the major impacts. The state does not use its full supply of Colorado River water and most of the water used indoors by businesses and homes in the populous southern part of the state is recovered, treated and returned to Lake Mead. is recycled.


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