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Along the Rio Grande, disputes over water heat up with climate change

A little known international organization is in charge of mediating U.S.-Mexico water sharing during a time of drought.

The Rio Grande Gorge in northern New Mexico (AN/R. Powers)

TAOS, New Mexico (AN) — The Rio Grande is one of the most storied, significant and historic natural wonders of the American West. Now, thanks largely to human-caused climate change, this iconic waterway that forms a border between two oil-rich nations is a symbol of our impending future: summers of more searing heat waves, masses of people on the move, and mounting international conflict over Earth’s most treasured and vital resource: water.

The politically charged crisis along the U.S.-Mexico border, with migrants flocking to the river in desperate bids to get into the United States, is widely known. Unfolding largely under the radar is a long-running international dispute over how to share and conserve the water that flows into the Rio Grande, as it is known in the U.S., or the Rio Bravo in Mexico.

As with many thorny and contentious problems, the basic issue is straightforward: Mexico is far behind in delivering water to the United States that it had promised in a World War II-era bilateral treaty.

On the Mexican side, officials say that due to drought they simply cannot deliver water they do not have. Interested U.S. parties – farmers, water managers, and city and town officials who depend on the river – aren’t buying it and are calling on Mexico's government to do more. The dispute gives politicians in Texas and Washington a chance to do what they do best: posture, issue ultimatums, and threaten to shut off the spigot of aid money.

U.S.: The situation is 'dire'

In the middle of it all is an odd duck of an international organization, little known outside the Rio Grande Valley, with no real enforcement power.

The International Boundary and Water Commission, or IBWC, monitors and governs Rio Grande water-sharing between the U.S. and Mexico and serves as the arbiter in cross-border debates over water management.

Complicating matters, the U.S. and Mexico have separate divisions of the bifurcated IBWC, with the U.S. IBWC based in El Paso, Texas, falling under the U.S. State Department's oversight. The Mexican counterpart, Comisión Internacional de Límites y Aguas, is based in Ciudad Juarez, just across the river from El Paso, under the Secretariat of Foreign Relations' jurisdiction.

“We haven’t gotten any rains or significant inflows,” the head of the U.S. IBWC, Maria-Elena Giner, recently told farmers and irrigation managers at a meeting in El Paso. “It’s not looking good.”

At another gathering in the Texas border town of Mercedes, she summarized bluntly: “Right now, where we’re at with the water levels, it is a very dire situation.”

Barring a major climatic event, such as a hurricane moving through the region, it’s looking to be another very dry summer. Earlier this year the water shortage forced the only sugar mill in the region, near Mercedes, to close; without massive amounts of irrigation Texas farmers cannot grow such a water-intensive crop as sugar cane in a place that’s naturally arid.

With reservoirs along this stretch of the Rio Grande at record lows, Texas state officials say consumption reductions will be needed. Meanwhile, communities on both side of the border worry about running out of water and accommodating future growth.

Experts say Mexico isn't able to fulfill the deal

Adding to the water woes, a pre-summer heat dome has pushed temperatures on both sides of the border to record highs, making a decades-long regional mega-drought even more severe.

Eighty years ago, Mexico and the United States signed the Water Treaty of February 3, 1944, obligating the U.S. to send 1.5 million acre-feet of water from the Colorado River each year to Mexico.

Mexico has to deliver 1.75 million acre-feet of water to the United States every five years. Most of that water comes from the Rio Conchos, which springs from the mountains of northwest Mexico, flows through the farmland of Chihuahua, and joins the Rio Grande near Presidio, Texas.

Later, the Boundary Treaty of 1970 resolved boundary differences between the two countries and provided for maintaining the Rio Grande and Colorado River as the international boundary. It includes procedures to avoid the loss or gain of territory based on future changes in the river.

Chihuahua is suffering through drought and Mexico's reservoirs on the Conchos are at only a quarter of capacity. The treaty's five-year cycle won't end until Oct. 2025 and, technically, Mexico won't be in debt until then.

So far, according to the IBWC, during the current cycle, Mexico has paid less than 400,000 acre-feet of water and most experts believe the country will not be able to make good on the balance.

An acre-foot is the volume of water needed to cover an acre of land to a depth of one foot, equivalent to 43,560 cubic feet or about 325,851 gallons, roughly what three or four typical American households use each year.

Droughts and a dramatic increase in demand for water after the 1994 U.S.-Mexico free trade agreement – when factories sprung up along the south side of the border and Mexican farmers moved to growing water-intensive fruits and vegetables for a newly opened U.S. market – made it increasingly difficult for Mexico to meet its obligations.

The water treaty includes no stated mechanism for dealing with noncompliance, leaving disputes to be resolved by water commissioners from the two countries or addressed diplomatically.

Renegotiate the deal?

Mexico’s president-elect, Claudia Sheinbaum, an environmental engineer before she went into politics, said during the recent presidential campaign that she would focus on energy and water-use reform. But Mexico has a powerful and vocal agriculture sector, and political pressure is building to renegotiate the treaty; it remains unclear what Sheinbaum plans to do and how she would accomplish any substantial reform.

In the U.S., lawmakers want Secretary of State Anthony Blinken and the IBWC to be more assertive in pressuring Mexico into compliance. “We need to use every tool that we have available to force Mexico to abide by the treaty. We want our water. We demand our water,” says Monica De La Cruz, a U.S. congresswoman from the south Texas border town of McAllen.

The quality of the water and questions on how to use, share and conserve this scare resource is a common theme. Learning to making do with less is part of the everyday conversation of farmers, ranchers, city managers and outdoor enthusiasts who float, fish, hike and hunt along the Rio Grande.

Management of the river has produced bitter disputes and lawsuits for decades, with one case involving the U.S. states of New Mexico, Texas and Colorado pending in the U.S. Supreme Court.

From its source in southern Colorado’s San Juan Mountains, the Rio Grande flows south through New Mexico then veers southeast to mark the border of Texas and Mexico. Some 3,051 kilometers (1,896 miles) from its alpine source, the mostly played-out river ends in a small sandy delta at the Gulf of Mexico, not far from Elon Musk’s Space X launch facility.

In southern Colorado’s San Luis Valley, near the Rio Grande's headwaters, ranchers whose wells draw from aquifers recharged by the river find its water quality deteriorating from overuse and increasingly unreliable snowfall across the San Juan and Sangre de Cristo mountains that feed it.

Hundreds of miles south, farmers and ranchers in both the U.S. and Mexico are dealing with irrigation water that is becoming saltier and less healthy for plants and animals.

The river runs dry

In the miles between, fragile ecosystems are threatened and reservoirs remain at near historic low levels. In some places for much of the year the river runs low enough to wade across, or is even dry.

There’s a saying in south Texas: If you fall into the Rio Grande,
just get up and brush the dust off your boots.

The U.S. government recently announced that over the next few years, it will spend US$60 million for conservation projects along the Rio Grande in southern New Mexico and Texas.

“When drought conditions like this strike, we know it doesn’t just impact one community, it affects us all,” said the U.S. Interior Secretary Deb Haaland, a Native American and member of the Laguna Pueblo tribe.

"When the well is dry, we know the worth of water" – Benjamin Franklin