The Colorado River’s largest reservoir, Lake Mead, has seen water levels drop to new records. A white “bathtub” ring of minerals runs along its perimeter. It marks the spot where the high water mark was once. This highlights the water problems facing the region, which is now experiencing a growing population as well as a drought, which is made worse by the hotter and drier climate caused by climate change.

States, cities and farmers have diversified their water sources over time, which has helped to ease the impact of the cuts. Federal officials stated Monday that the declaration made clear by federal officials shows that conditions have worsened faster than scientists expected in 2019. In 2019, some states from the Colorado River basin agreed not to share water in order to preserve Lake Mead’s levels.

Camille Touton, Bureau of Reclamation Commissioner, stated that today’s announcement is “a recognition that hydrology that was planned years ago but that we hoped would never see — it is here.”

The Hoover Dam was built in the 1930s to create Lake Mead. It is one of many man-made reservoirs that store water of the Colorado River. This water supplies irrigation water for farms, household water, and hydropower to Arizona and California.

But water levels at Lake Mead and Lake Powell, the river’s two largest reservoirs, have been falling for years and faster than experts predicted. The river’s flow from the Rocky Mountains (where it originates) has been reduced by scorching temperatures and less melting of snow in the spring.

“We are at a point where we’re dealing with how we can continue to thrive with less water and it’s very difficult,” stated Sarah Porter, director at the Kyl Center for Water Policy, Arizona State University.

HOW IS THE RIVER WATER SHAREABLE?

The legal agreements between the seven Colorado River basin states and the federal government, Mexico, and other parties to the water storages at Lake Powell and Lake Mead determine how the water is divided up. These agreements establish how much water each party gets, when cuts will be triggered, and in what order they must sacrifice some.

A 2019 drought contingency plan required Arizona, Nevada and California to agree to share their water in order to maintain Lake Mead’s water level. These voluntary measures were not enough to stop the declaration of shortage.

WHO DOS LAKE MEAD SERVE?

Lake Mead provides water for millions of people in Arizona and California, Nevada, and Mexico.

When water levels are predicted to fall below a threshold, which is 1,075 feet (328m) above sea level or 40% capacity, cuts for 2022 will be triggered. The reservoir will fall to 1,066 feet (325m) by January according to hydrologists.

Additional rounds of cuts will be initiated when levels fall to 1,050 or 1,045 feet (320, 318, and 312 meters).

Some industrial and city water users may be affected eventually.

Lake Powell’s levels are also falling, which could threaten the Glen Canyon Dam’s roughly 5 billion kilowatthours of electricity each year.

Colorado, New Mexico and Utah get their water from tributaries that flow into Lake Powell. Three reservoirs from those states have been drained to preserve the Glen Canyon Dam’s electric grid and maintain Lake Powell water levels.

Which STATES WILL BE AFFECTED DURING THE CUTS?

Arizona, the U.S. state hardest affected, will lose 18% of its share of the river’s flow next year, or 512,000 acres of water. That’s around 8% of the state’s total water use.

One acre of water is sufficient to supply two households per year.

Nevada will lose approximately 7% of its allocation or 21,000 acre feet of water. It will not feel the shortage due to conservation efforts.

California is exempt from immediate cuts due to its higher senior water rights than Arizona or Nevada.

Mexico will see an approximate 5% reduction, or 80,000 acres-feet.

Who WILL LOSE THEIR WATER SUPPLY IN THOSE STATES?

Farmers in central Arizona, who are among the state’s largest producers of livestock, dairy, alfalfa, wheat and barley, will bear the brunt of the cuts. They will be the first to go without water in a drought because they are the ones who have water that is considered “extra”.

Farmers will have to abandon their land, as they did in the past due to drought. They will also need to rely more on groundwater and switch to water-efficient crops.

Water suppliers have prepared for the declaration of a shortage by diversifying their water supply and conserving it, such as by storing the water in underground basins. Water cuts make planning for the future more difficult.

Because of the cuts, the Central Arizona Project, which supplies water water to Arizona’s major cities will no longer be able to bank river water or replenish groundwater systems next year.

Chuck Cullom, Central Arizona Project, stated that “it’s an historic moment when drought and climate change have at our door.”

The first round of cuts is not applicable to cities like Las Vegas, Phoenix, Tucson, or Native American tribes.

CAN THE DECLINE IN LAKE MEAD BE REVERSED

The dry spell that engulfed the West in 1999 and the increased demand for water have caused the reservoir’s water levels to fall since then. Experts predict that the reservoir will never again be full due to weather patterns expected worsening.

Although Lake Powell and Lake Mead could theoretically be filled, it would be prudent to plan for a warmer, drier future that has less river water, according to Porter, Arizona State University.