How New Colorado River Cuts Will Affect States, Residents?

WASHINGTON — Arizona and Nevada residents will not face a ban on watering their lawns or washing their cars, despite increased water shortages in the Colorado River.

But US officials announced Tuesday that less water will be available to them next year from the river that serves 40 million people in the West and Mexico and an agricultural industry worth billions of dollars. Observers warn there is still a reckoning for the growing region as the water crisis is expected to lead to budget cuts in the future.

A look at the critical water source for the western US and the water outages.

WHY IS THE COLORADO RIVER THREATENED?

There are two Colorado rivers in the US – the 1,450 miles (2,334 kilometers) powerhouse of the West and the more than 800 miles (1,287 kilometers) river that begins and ends in Texas.

The river that cuts off is the longest. It supplies seven states plus Mexico, but its flow has dropped dramatically over time due to agriculture’s overuse of water and growing population, higher temperatures, evaporation and less snowmelt in the spring to replenish the river.

And for years, the seven states that receive the water from the river have taken more water from it than was replenished by nature.

WHO DO LAKE MEAD AND LAKE POWELL SERVE?

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

Cuts for 2023 are triggered when forecast water levels fall below a certain threshold — 1,050 feet (320 meters) above sea level.

Additional cuts will be triggered when projected levels drop to 1,045 and 1,025 feet (319 and 312 meters). At some point, the level may become so low that no more water can be pumped from the reservoir.

Eventually some users of city and industrial water will be affected.

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

Colorado, New Mexico, Utah and Wyoming get water from tributaries and other reservoirs that lead to Lake Powell. Water from three reservoirs in those states has been drained in recent years to maintain water levels at Lake Powell and protect the Glen Canyon Dam’s electrical grid.

WHAT IS CUT AND WHY?

The federal government has started cutting supplies to some states this year to maintain water levels in the river and major reservoirs. New water savings will build on those cuts — virtually eliminating the supply of water from the Colorado River by some farmers in central Arizona and reducing Nevada and Mexico’s share to a much lesser extent.

Lake Mead and Lake Powell — the Colorado River’s two largest reservoirs — are about a quarter full, threatening the water supply and hydroelectric power generation that powers millions of people.

Along the rims of the reservoirs, “bathtub rings” of minerals outline where the high-water mark once stood, highlighting the challenges the west faces as a megadrought tightens its grip on the region.

HOW IS THE RIVER SHARED?

Colorado, Wyoming, Utah, and New Mexico divide the Colorado River into what is called the river’s upper basin. 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 water. The river’s water traditionally flowed through Mexico and reached the Gulf of Calfornia, but it rarely does anymore because so much is used by farms and cities. Among those who depend on the water are nearly 30 federally recognized Native American tribes.

In the Southwest, water stored in Lake Mead and Lake Powell — the two largest man-made reservoirs in the US — is distributed through legal agreements between the Colorado’s seven watershed states, the federal government, Mexico, and tribes. The agreements determine how much water each entity will receive, when to cut spending, and in what order the parties must sacrifice some of their supply.

Under a 2019 drought emergency plan, Arizona, Nevada, California and Mexico agreed to give up portions of their waters to maintain water levels at Lake Mead. This year’s austerity measures are part of that plan — and as a result, state officials knew they were coming.

WHICH PARTIES WILL BE AFFECTED BY THE austerity measures?

Arizona, Nevada and Mexico.

Arizona was again the hardest hit and will receive 79% of its total share next year. But that’s just 3% less than what it got this year after federal officials cut the supply.

Nevada will receive about 92% of its total supply next year. Most residents won’t feel the cuts thanks to water conservation, reuse, and the state not using the full allotment.

California has been spared because it has higher water rights than Arizona and Nevada. That means it doesn’t have to give up its water first, according to the hierarchy that directs water law in the American West.

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

WHO LOSE WATER?

Farmers in central Arizona, one of the largest producers of livestock, dairy, alfalfa, wheat and barley, lost most of their allocation to the Colorado River this year as the government introduced its first deficit. Some farmers were compensated with water through deals with cities like Phoenix and Tucson.

More farmers will likely have to leave their land fallow – for which some farmers in the region have been paid by government agencies and others – and will be even more dependent on groundwater. Others will be forced to grow more water-efficient crops like durum wheat and guayule and find other ways to use less water.

Western water suppliers have planned for such shortages by diversifying and preserving their water sources. But intensifying droughts that are depleting reservoirs faster than scientists had predicted — and the resulting budget cuts — will make it harder for farms and cities to plan for the future.

“Most people are also unprepared for the kind of tough choices we have to make,” said Mark Squillace, a professor of environmental law at the University of Colorado. “And that’s kind of the situation we’re facing in the Colorado River.”

Phoenix will lose some water that it would otherwise store in underground basins as a water reserve, said Cynthia Campbell, the city’s water management consultant. That happened this year too. The city will need 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 sixth largest in the country.

Nevada will also face budget cuts, but residents will not be greatly affected. The state does not use its entire supply of water from the Colorado River, and most of the water used indoors by businesses and homes in the densely populated southern part of the state is reclaimed, treated, and recycled and returned to Lake Mead.

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