Thứ Ba, Tháng Năm 30, 2023
HomeNewsThe US offers options to solve the Colorado River crisis

The US offers options to solve the Colorado River crisis

The federal government on Tuesday presented two options to prevent the Colorado River’s depleted reservoirs from falling to extremely low levels, saying it could impose cuts across the Southwest by following systems that prioritize water rights or by using comprehensive percentages.

The risks of this decision are great for California, which receives the largest amount of water from the Colorado River. The full-blown cuts could hit California harder, especially agricultural regions.

The U.S. Bureau of Reclamation presented its alternatives as a first step in a review process aimed at revising rules to address shortages through 2026. The cuts, if approved, could affect cities and farming areas in California, Arizona and Nevada.

The river’s largest reservoirs, Lake Mead and Lake Powell, have significantly reduced during 23 years of drought caused by climate change. Even after hurricanes blanketed the Rocky Mountains with their biggest snowfall since 1997, federal officials say the possibility of a return of dry conditions means the region still needs a plan. allocate additional water cuts as needed over the next three years.

Deputy Interior Secretary Tommy Beaudreau said: “Everybody understands the magnitude of the crisis. “I think everyone understands that, fortunately and gratefully, we’ve had a lot of rain, that no one has been affected and needs to continue to be united in trying to develop solutions.”

Representatives from seven states, water agencies and tribes discussed water use reduction options to prevent reservoirs from dropping to dangerously low levels. Closed negotiations will continue while the federal government receives input on the proposals.

The Bureau of Reclamation says it has published an initial assessment of the alternatives, called draft additional environmental impact reportto “address the possibility of continued low-flow and unprecedented water shortages in the Colorado River Basin.”

The agency is revising 2007 guidelines for the operation of the Glen Canyon and Hoover Dams, to include measures to deal with water shortages through 2026 — but federal officials say there will be no more. enough if the reservoirs continue to decline.

The Biden administration laid out its options more than two months after officials from California and six other states present two opposing proposals to reduce water.

As an alternative, the federal government would consider implementing water cuts primarily based on the existing prioritization system for water rights.

That means fewer or no cuts for agencies and organizations that hold higher-level rights, including agricultural suppliers such as California’s Royal Irrigation District, which uses the the largest Colorado River water to provide approximately 500,000 acres of farmland in the Royal Valley. Strict adherence to the water rights priority system also means that low-grade water rights holders begin to draw water from rivers that are subsequently cut back significantly, such as the Central Project Arizona, which supplies Phoenix, Tucson, and other Arizona cities.

Under the second alternative, the Bureau of Reclamation would analyze the impact of cuts “distributed by the same percentage” for all water users in the three Lower Basin states, California, Arizona. and Nevada.

This approach means comprehensive cuts for all water users in the region, including senior water rights holders, equivalent to a reduction of about 13% compared to the agreed reductions. Under the 2019 agreement, agricultural irrigation districts, cities and tribes are all required to participate based on a schedule of reductions tied to Lake Mead’s water levels.

Beaudreau said this second alternative would reflect the Interior Secretary’s authority to “provide for human health and safety” and manage supplies during emergency conditions. If reservoir levels fall further and additional cuts are triggered, this approach would increase allocations to agencies with more lower-grade water rights, such as cities in Arizona. , Nevada and Southern California.

A vertical frame of a river meanders through the arid hilly landscape

A pumping plant marks the beginning of the Colorado River Aqueduct, where the Southern California Metropolitan Water District draws water from Lake Havasu. The district’s Copper Basin Reservoir is the third major stop for Colorado River water en route to Southern California.

(Brian van der Brug/Los Angeles Times)

Both of these alternatives would call for progressively larger amounts of water as Lake Mead levels drop. The total amount of potential cuts in 2024, including those under existing agreements, could reach a little over 2 million acres — a large reduction compared to the combined allocations of the three states. state is 7.5 million acres.

Last year, federal officials called for cutting water use by 2 million to 4 million acres a year to address chronic water shortages and the effects of climate change.

The federal review will also consider an “alternative no-action,” analyzing the consequences of complying with existing rules and agreements if dry conditions return after a wet winter last year. now.

“If only, after a quarter of a century of drought, a good year would get us out of the deficit. But it’s not,” Beaudreau said.

He points out that between 23 years of drought, there are wet years, such as 2011, after which drought returns. Heavy snow this winter could push the “curve out by six months or more,” he said.

“But the trend is still clear this time around and clear in the pattern,” says Beaudreau. “And it’s in the basin’s interest to continue to drive the analysis and the negotiations, and not throw stones at it.”

The Bureau of Reclamation will accept public comment on draft proposals for 45 days, and Beaudreau said the agency expects input from states, tribes and agencies. water authority on “refining or adapting such alternatives”.

The government plans to adopt a final decision this summer, which will guide dam operation and water release next year.

The proposals would also provide “supports” to support ongoing negotiations among seven river-dependent states on additional voluntary conservation measures, Beaudreau said.

“I am really encouraged by the commitment in the basin to continue those conversations,” Beaudreau said.

“I think what will spur the conversation is to write something down that shows those bonds,” he says. “There’s really a lot of consensus in the basin about the commitment to meeting those conservation goals.”

In addition to addressing a three-year approach, managers of water utilities still need to negotiate new rules to address water shortages beyond 2026, when current rules expire. force.

Whatever the federal government decides to choose, much will depend on reservoir levels over the next three years.

In the Rocky Mountains, the upper Colorado River Basin snow cover now measures 149% of the average since 1986, making it one of the largest snowfalls since 1980.

This spring and summer runoff will raise the water level of Lake Powell on the Utah-Arizona border, and the water will flow to Lake Mead, which stores supplies for Southern California, Arizona, Southern Nevada, and Northern Mexico.

Lake Mead, currently at only 28% of its maximum capacity, is expected to rise with the flow. But both large reservoirs are expected to remain below half full.

“The drought situation in the Colorado River Basin dates back two decades,” said Camille Calimlim Touton, Reclamation Commissioner, Camille Calimlim Touton. “To meet this moment, we must continue to work together, through a commitment to protecting the river, led by science and a shared understanding that unprecedented conditions call for new solutions. .”

Since 2000, river flows have decreased by about 20% compared to the 20th century average. Scientists have found that about half of the decline in river flows is due to high temperatures. further aggravated one of the worst droughts in centuries.

Beaudreau said the main goal is to provide “additional tools in case the hydrology continues to deteriorate”.

The Home Office has also begun providing funding to address drought, pay for efforts to conserve and improve water infrastructure, based on $8.3 billion from the Bipartisan Infrastructure Act. and $4.6 billion from the Inflation Reduction Act.

Last week, federal officials announced that the Gila River Indian Community in Arizona will receive $150 million over the next three years to pay for reducing water use and leaving some of it in Lake. Mead.

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