U.S., Mexico strike new deal to manage usage, conservation of Colo. River water
The United States and Mexico have agreed to update and extend a 2012 deal through which Americans invest millions of dollars in Mexican water conservation in exchange for a share of Mexico’s Colorado River water.
The deal spreads the costs of conservation and the pain of future droughts and shortages across the river’s millions of users north and south. The river supplies water to about 40 million Americans Republic editorial: Water accord is critically important for Arizona.
from Denver to Los Angeles.
Whenever drought forces the U.S. to impose cuts under a planned drought contingency plan, the International Boundary and Water Commission said Wednesday, Mexico will agree to cut its take of the river “in parity with U.S. savings.”
The commission said officials from the two nations signed the agreement in a ceremony in Santa Fe. Under the deal, the U.S. government and southwestern
water users will invest up to $31.5 million in water-delivery systems and farm-efficiency upgrades south of the border.
In exchange, Mexico will parcel out a portion of its river allotment to various U.S. water agencies over nine years, and will reduce the risk of shortages for all of the Southwest by storing some of its water in Lake Mead near
Las Vegas.
“This agreement puts us on a path of cooperation rather than conflict as we work with Mexico to address the Colorado River Basin’s many challenges,” U.S. Commissioner Edward Drusina said in a statement.
After the deal’s signing, he added that it’s “not necessarily the complete fix,” given the region’s long-term drought, but is a “monumental achievement in collaboration.”
The deal “provides certainty for water operations in both countries,” Mexican Commissioner Roberto Salmon said, and allows Mexico to better plan its water use.
A 2007 rule adopted by the states allows the federal government to restrict some of Arizona’s water whenever Lake Mead’s elevation drops below 1,075 feet above sea level to start a year.
That reservoir had threatened to drop that low before healthy Rocky Mountain snowfall last winter raised levels, but officials project there’s still about a 1-in-3 chance it could happen by 2019.
The U.S. is entitled to 15 million acrefeet from the Colorado, but in recent years has had to draw more from the big reservoirs to get that while still delivering the 1.5 million acre-feet due Mexico.
On the lower river, water is divided among Mexico and three U.S. states. Arizona receives 2.8 million acre-feet per year, California 4.4 million acre-feet and Nevada 300,000 acre-feet.
An acre-foot would cover an acre a foot deep, roughly enough to supply two Southwest households for a year.
Mexico may store as much as a sixth of its yearly share of the river in Lake Mead, helping everyone avoid shortage. In years with adequate water, it can retrieve most of that on top of its regular annual share. But if the reservoir drops to 1,025 feet elevation, when the basin would face crisis, Mexico would not retrieve its stored water.
The U.S.-Mexico agreement does not explicitly authorize a “pulse flow” to the ocean like the environmental restoration experiment that Mexico requested and got in 2014.
With that, Mexico spilled some of its own water past a borderlands dam to restore vegetation along the normally dewatered delta.
The deal does allow more regular but targeted flows to certain stretches where nonprofit groups have planted trees on the delta.
The deal, labeled Minute 323 as an addition to a 1944 treaty dividing the river’s flow, updates a 2012 agreement in which Mexico for the first time agreed to leave some of its share in the U.S. in the event of a shortfall that curtails deliveries to Arizona and Nevada.
Mexico needed help restoring and lining canals damaged by an earthquake, and in return, U.S. agencies, including the Central Arizona Project, chipped in millions and received rights to some of Mexico’s water.
This time, the CAP will pay $3.75 million for Mexican infrastructure improvements over nine years and will receive 27,000 acre-feet for future use by its customers in the Phoenix and Tucson areas, said Chuck Cullom, the agency’s river operations chief.
In all, U.S. water providers will get up to 109,100 acre-feet of Mexico’s projected water savings for their total investment. That’s more than Tucson Water delivers to customers in a year.
Gov. Doug Ducey said the agreement would protect states from shortages while affirming the relationship on the river between the U.S. and Mexico.
“Minute 323 allows the states and Mexico to form the partnerships necessary to achieve the goal of protecting Lake Mead, while at the same time protecting the state’s Colorado River water users,” Ducey said in a statement.
Tom Buschatzke, director of the Arizona Department of Water Resources, participated in the signing ceremonies Wednesday. The agreement, he said, “provides substantial benefits to Arizona, particularly regarding opportunities for augmenting existing water supplies.”
About 50,000 acre-feet from Mexico’s conservation will remain in the system to prevent shortages, and 70,000 acrefeet will be for environmental flows.
The CAP and other U.S. water agencies also will help fund a study of seawater desalination options on Mexico’s Sea of Cortez, which eventually could enable Mexico to use the ocean and leave a larger portion of its river share for cooperating U.S. interests.
“This is an important new step in the collaboration between Arizona, the United States and Mexico to protect Lake Mead and to continue our cooperative relationship,” Cullom said, “and hopefully continue to avoid shortages on the Colorado River.”
California’s largest urban user of Colorado River water also is contributing.
“We’re laying the groundwork for a long, good partnership and that’s promising,” said Jeffrey Kightlinger, general manager of the Metropolitan Water District of Southern California.
The Metropolitan Water District supplies water to 26 member cities and districts, which in turn provide water to 19 million people across Southern California.
Kightlinger said the U.S.-Mexico agreement shows “there can be a long, fruitful partnership.”
The 2014 “pulse flow” was a successful experiment, he said, and the next step is to create permanent habitat areas and “make sure we have water for them.”
Restoring cottonwoods and willows to a dry delta that has grown over with nonnative salt cedars is important to migratory birds that live in both countries.
Those efforts including backing from U.S. foundations, who pledged continued support.
“We stand ready to be partners,” said Ted Kowalski, head of the Walton Family Foundation Colorado River initiative. “We would be interested in augmenting that restoration work, which will take water and funding.”