Arizonans and Nevadans won’t face bans on watering their lawns or washing their cars despite new cuts to water supplies from the Colorado River.
However, the federal authorities announced that next year those states will have less liquid available from that river, which supplies 40 million people in the west of the country and Mexico, as well as an agricultural sector whose production reaches a value of thousands of millions of dollars. Observers warn of an upcoming adjustment for the area because the water crisis is expected to force more cuts in the future.
Here’s a look at this crucial water source for the western United States and the supply cuts.
WHY IS THE COLORADO RIVER THREATENED?
There are two Colorado Rivers in the United States: the mighty 1,450-mile (2,334-kilometer) river in the west of the country and a little over 800-mile (1,287-kilometer) river that begins and ends in Texas.
The river facing the cutouts is the longest. This supplies water to seven states and Mexico, but its flow has drastically decreased over the years due to its excessive exploitation for agricultural use and population growth, the increase in temperatures, evaporation and less snow melting during the winter. spring to replenish.
And for years, the seven states that receive water from the river have consumed more than Nature replenishes.
WHO DOES LAKE MEAD AND LAKE POWELL SUPPLY?
Lake Mead supplies water to millions of people in Arizona, California, Nevada, and Mexico.
Supply cuts in 2023 will kick in when forecast water levels drop below a certain threshold: 320 meters (1,050 feet) above sea level.
Additional reductions will be imposed if forecast levels drop to 1,045 and 1,025 feet (319 and 312 meters) above sea level. At one point, the levels could drop so low that water could no longer be pumped from the reservoir.
Ultimately, some water users in cities and industrial sectors will be affected.
The level in Lake Powell is also falling and extraordinary measures have been taken to conserve water in the reservoir, located on the border between Arizona and Utah.
Colorado, New Mexico, Utah, and Wyoming receive water from tributaries and other dams that supply Lake Powell. In recent years, water from three reservoirs in those states has been used to maintain the level of Lake Powell and keep the power grid running, which receives power generated at Glen Canyon Dam.
WHAT ARE THE SUPPLY CUTS AND WHY?
The federal government began reducing supplies in some states this year to maintain water levels in the river and its main reservoirs. The new cuts will be in addition to the current ones, which left some farmers in central Arizona virtually without water from the Colorado River and, to a much lesser extent, reduced corresponding volumes in Nevada and Mexico.
Lake Mead and Lake Powell — the Colorado River’s two largest reservoirs — hold a quarter of their normal amount of water, threatening water supplies and hydroelectric generation that power millions of people.
At the perimeter of the reservoirs, “bathtub ring” markings formed by minerals embedded in the rock indicate where the water level was once located, highlighting the difficulties facing the western region as a “megadrought” exacerbates its effects.
HOW IS THE RIVER WATER DISTRIBUTED?
Colorado, Wyoming, Utah, and New Mexico share the Colorado River in the so-called upper river basin. Arizona, Nevada, and California make up the lower basin.
From its source in Colorado, the river and its tributaries eventually flow south of the border to Mexico, which also taps its share. The river water used to flow through a small part of Mexico and emptied into the Gulf of California, but this rarely happens anymore because much of it is used by farms and cities. Those dependent on the water include nearly 30 federally recognized Native American communities.
In the Southwest, the water stored in Lake Mead and Lake Powell—the largest pair of artificial reservoirs in the United States—is distributed through legal agreements among the seven states of the Colorado River basin, the federal government, Mexico, and the United States. indigenous communities. The agreements determine how much each party receives, when the cuts are triggered, and the order in which the parties must sacrifice some of their supply.
Under a 2019 contingency plan to deal with the drought, Arizona, Nevada, California and Mexico agreed to give up parts of their liquid to conserve the water level in Lake Mead. This year’s cuts are part of that plan, so state officials knew they would come.
WHAT PARTS WILL BE AFFECTED BY THE CUTS?
Arizona, Nevada and Mexico.
Arizona was hit the hardest again, and next year it will receive 79% of its fair share. But that amount is just 3% less than what he received this year after federal authorities cut his supply.
Next year Nevada will receive about 92% of its total. Most residents will not feel the cuts thanks to the conservation and reuse of the liquid since the state will not use all of its allotted volume.
California is exempt from the measures because it has more priority water rights than Arizona and Nevada. This means you don’t have to be the first to give up your water, according to the hierarchy that guides water law in the western United States.
Mexico will receive about 93% of its total supply. The water is used in cities and farming communities in the northwest of the country, which is also experiencing a severe drought.
WHO WILL LOSE WATER?
Farmers in central Arizona — among the state’s largest producers of cattle, dairy, alfalfa, wheat and barley — lost most of their allocation from the Colorado River this year after the government launched its first cut. Some farmers were compensated with water through agreements with cities like Phoenix and Tucson.
More farmers will likely need to idle their land—some of them have received grants from agencies and other sources to do so—and increase their reliance on groundwater. Others will be forced to grow less water-consuming crops like durum wheat and guayule, and find other ways to economize on water use.
In anticipation of cutbacks, water providers in the western part of the country have diversified and conserved their water resources. But the depletion of reservoirs at a faster rate than scientists predicted — and the resulting cutbacks — due to the worsening drought will make it even more difficult for farms and cities to plan ahead.
“Most people are also not prepared for the kind of tough decisions we need to make,” said Mark Squillace, a professor of environmental law at the University of Colorado. “And that’s the kind of situation we’re facing on the Colorado River.”
Phoenix will lose some water that would otherwise be stored in groundwater basins as a water reservoir, said Cynthia Campbell, a water resources management adviser for the city. That also happened this year. The city will rely more on water from Arizona’s Salt and Verde rivers.
Campbell said Phoenix residents and businesses will not be affected. The city, which in the 1950s was a sleepy desert community, is now the fifth largest in the nation.
Nevada will also face cutbacks, but residents won’t see sharp declines in supply. The state does not use its entire allotment of Colorado River water and reclaims, treats and returns to Lake Mead most of the liquid used indoors by businesses and homes in the populous South.