A U.S. Supreme Court case over how water from the Rio Grande is allocated is underway and may finally put an end to a years-long dispute over how border states use the precious resource.
The river supplies water to millions of people and wildlife along its shores in Colorado, New Mexico, Texas and Mexico. Nearly 80% of its water is used in agriculture, but it’s also a major source of water for cities like Albuquerque and El Paso.
The dispute over the river’s water between the states and the federal government started a decade ago. In a 2011 federal lawsuit, New Mexico alleged the federal government shorted New Mexico its share of Rio Grande water, and gave too much to Texas. It escalated when Texas filed a new lawsuit against New Mexico in the U.S. Supreme Court three years later.
Below is El Paso Matters’ guide to the people, agencies and arguments in the case, officially called Original 141: Texas versus New Mexico and Colorado.
The waters
The Rio Grande is a 1,885-mile-long river fed by snowmelt in the San Juan Mountains of southern Colorado, then winds its way down through New Mexico, into Texas, and then becomes the border between the United States and Mexico.
It provides water for more than 6 million people and several cities, including Albuquerque and El Paso. It waters crops such as chile, onions, pecans and cotton. It provides habitat for a variety of wildlife across different biomes.
The river officially ends at the Gulf of Mexico, but there is a section south of Fort Quitman, Texas (about 90 miles downstream of El Paso and Ciudad Juárez), where the river ends, called the “lost reach.” Tributaries then feed into the river bed and revive the Rio Grande downstream.
Groundwaters used to feed into the Rio Grande in the El Paso region, making the river “gain” more water as it flowed downstream. Pumping in the 20th century reversed that. Over decades, pumping in the Hueco Bolson dropped the water table in some places by hundreds of feet.
The dry, arid desert climate means only about 6,000-acre feet, or about 1.9 billion gallons a year, flow off the mountain from rains or snow. Water flows downhill, even if that means underground. About 33,00 acre feet per year flows out of the river into the groundwater in the region, according to hydrological models.
The Mesilla Bolson supplies groundwater to farmers in Southern New Mexico, Ciudad Juárez and the city of Las Cruces. It has a maximum thickness of 2,000 feet, extended 62 miles long and four miles wide under New Mexico and Chihuahua. The top portions of the bolson have fresh to slightly saline water, while deeper and older layers are increasingly salty.
The Hueco Bolson is about 200 miles long and 25 miles wide beneath Texas and Chihuahua. It has a maximum thickness of 9,000 feet deep. It contributes between 30% to 60% of El Paso’s drinking water depending on other supplies. Ciudad Juárez depends entirely on groundwater pumping for drinking water. Only the top several hundred feet of the bolson has fresh water while most of the other water is brackish and the lower portions are extremely salty.
El Paso Water pumps between 60,000 to 70,000 acre feet a year out of the Hueco Bolson for the city — between 19 billion and 22 billion gallons. The utility uses injection wells to return about 3 million gallons a day of treated wastewater into the aquifer and has replenished the aquifer with more than 30 billion gallons since the 1990s.
Treaties, policy and agreements
The 1906 Rio Grande Convention is a treaty on the Rio Grande that requires the United States — barring extraordinary drought or serious accidents to the U.S. irrigation system — to deliver 60,000 acre feet of water annually to Mexico at the Acequia Madre near El Paso and Ciudad Juárez. Under either of those exceptions, there’s a proportional reduction of water to Mexico equal to water given to U.S. irrigators. The treaty is for the Rio Grande upstream of Fort Quitman in Texas.
The 1938 Rio Grande Compact resolved disputes over the water rights on the Rio Grande, and was signed by the states of Colorado, New Mexico and Texas and approved by Congress.
The compact lays out how the states split the water. It requires Colorado to deliver a proportion of water each year to New Mexico at the state line. It also directs New Mexico to deliver a specified proportion of water in the Elephant Butte Reservoir. That water is used to supply downstream irrigation districts in New Mexico and Texas (called the Downstream Contracts) and gives Mexico its share outlined in the 1906 Convention. The river is measured at specific water gauges, to ensure the water is being divided appropriately.
The compact establishes the Rio Grande Commission to enforce and monitor the agreement. Each state is represented by a commissioner, for a total of three commissioners. The federal government acts as the chair, but does not have a vote.
The compact also limits the amount of water each state can borrow from downstream states. Colorado cannot exceed 100,000 acre feet and New Mexico cannot exceed 200,000 acre feet.
The compact also limits which upstream reservoirs can be used to store water in times of drought.
The Rio Grande Project is a federal initiative that provides irrigation water in Southern New Mexico and West Texas to about 178,000 acres of land. The project’s drainage irrigates an additional 18,000 acres in Hudspeth County.
Construction to build out the irrigation system started in 1908 to ensure Mexico gets its share of water under the requirements of the 1906 Convention. The physical features of the project include Elephant Butte and Caballo Dams, six diversion dams, 139 miles of canals, 457 miles of laterals, 465 miles of drains and a hydroelectric power plant. It is managed by the U.S. Bureau of Reclamation.
After decades of contention and lawsuits between the federal government, cities and irrigation districts in Texas and New Mexico, the 2008 Compromise and Settlement Agreement was created. It’s signed by the U.S. Bureau of Reclamation, and two irrigation districts: Elephant Butte Irrigation District and El Paso County Water Improvement District Number 1. The agreement explains the method of splitting the water and how balances for each of the districts are carried over. Neither Texas nor New Mexico were included in the agreement.
In 2011, the state of New Mexico sued the federal government in federal court, claiming the agreement shorted New Mexico on river water and gave too much to Texas. That lawsuit is on hold after Texas filed its claim in the Supreme Court in 2014 and claimed groundwater pumping in New Mexico decreased Texas’ portion of Rio Grande water.
Parties in the lawsuit
The state of Texas alleges in the 2014 complaint that New Mexico’s groundwater pumping removes tens of thousands of acre feet from the river, reducing Texas’ portion.
The U.S. Department of Justice is representing the federal government’s interests in the case and has sided with Texas. The federal government’s argument is that New Mexico’s “actions or inactions on groundwater” jeopardize the river, and the federal agencies’ duty to provide water for irrigators in the U.S. and give Mexico its portion of water under the 1906 treaty.
The state of New Mexico maintains it is not receiving its fair portion of Rio Grande water, which causes a reliance on groundwater as a replacement. The state also alleges that groundwater pumping in Texas also harms the Rio Grande.
The state of Colorado is named in the lawsuit only because it is a signatory on the 1938 Rio Grande Compact. It is not presenting a case in this matter.
The case is before the Supreme Court because it is a dispute between states.
Special master is a title given to a judge who acts as a fact-finder, oversees any trial and establishes a record to better inform the Supreme Court in the litigation.
The current special master is Judge Michael Melloy, a senior judge on the 8th U.S. Circuit Court of Appeals based in Cedar Rapids, Iowa. He was appointed the special master in 2018, after the U.S. Supreme Court discharged the first special master Gregory Grimsal, a New Orleans-based attorney, without explanation.
Other prominent players
The U.S. Section of the International Boundary and Water Commission is part of a binational agency jointly governed by the United States and Mexico. Its role is to ensure the treaties on water are fulfilled.
The U.S. Bureau of Reclamation studies and builds irrigation and reservoir infrastructure in Western states.
Elephant Butte Irrigation District was established by the state of New Mexico in 1985 and supplies water to more than 6,700 farmers in Southern New Mexico.
EBID argued in 2015 that the special master should allow the irrigation district official party status to the lawsuit, claiming the state of New Mexico was not fairly representing its interests. The special master denied that argument, declining to make the irrigation districts parties.
El Paso County Water Improvement District No. 1 supplies water to more than 32,000 irrigation accounts in El Paso County.
Both irrigation districts own canals and ditches that used to be property of the federal government in the Rio Grande Project.
Cover photo: The bed of the Rio Grande was dry at the State Highway 154 bridge near Rincon, New Mexico, on May 22. This year’s water release from Elephant Butte was delayed by low water levels. (Corrie Boudreaux/El Paso Matters)
