In South Texas, aging water system meets growing population

Oct 16, 2021, 10:22 AM | Updated: 10:43 am
A man casts a net into a canal, Tuesday, Sept. 14, 2021, in McAllen, Texas. Canals used to deliver ...

A man casts a net into a canal, Tuesday, Sept. 14, 2021, in McAllen, Texas. Canals used to deliver water in many parts of the Rio Grande Valley lose anywhere from 10% to 40% of the water they carry to seepage and evaporation, according to the Texas Water Development Board, making water a growing concern amid climate change and rising demand that scientists predict will lead to water shortages in the region by 2060.(AP Photo/Eric Gay)

(AP Photo/Eric Gay)

McALLEN, Texas (AP) — On a scorching afternoon in South Texas, Sonia Lambert looked out at an open-air canal that carries mud-green water from the Rio Grande to nearby towns and farmland, losing much of it to evaporation and seepage along the way.

“That will be someone else’s problem,” Lambert said, referring to her upcoming retirement as head of an irrigation district near the U.S.-Mexico border.

In the Rio Grande Valley, a canal system designed more than a century ago for agriculture still delivers water to the region’s lush farmland and fast-growing towns and cities. Today, the canals lose as much as 40% of the water they carry, waste that experts say could contribute to steep water shortages in coming decades as the population grows and climate change intensifies droughts.

“As this region continues to become drier due to climate change, water supplies will be greatly reduced,” said Guy Fipps, a professor of irrigation engineering at Texas A&M University who has studied the water system since 1998.

State water officials predict that over the next 50 years, demand for water in the area’s cities and towns will double. For decades, McAllen developed at a dizzying pace, with newcomers drawn to a large free-trade zone and jobs in health care, education and retail. Between 1990 and 2020, McAllen and the neighboring cities of Edinburg and Mission grew sixfold to nearly 871,000 people, according to the U.S. Census Bureau. Similarly, the Mexican cities of Reynosa and Matamoros across the border mushroomed after U.S.-owned assembly plants were established in the mid-1990s.

Further complicating matters is a 1944 treaty between the U.S. and Mexico that defines how the countries share water from the Rio Grande. Mexico is supposed to route 350,000 acre-feet of water every year to the U.S. — enough to supply as many as 700,000 households. But it has periodically failed to meet those obligations, delaying deliveries because of drought, tight water supplies and a thirsty crop industry in northern Mexico.

The late deliveries are a source of frustration, but water managers and farmers in the U.S. are quick to acknowledge a major challenge at home too: the leaky canal system that has long been seen by local and state officials as too expensive to overhaul.

The region’s more than 2,000 miles (3,219 kilometers) of pipelines and canals — some 100-feet (30 meters) wide — are meant for large, infrequent deliveries to farmland. Common fixes to modernize the waterways and make them more efficient — attempted by many districts to some degree — include lining earthen canals with concrete and more closely monitoring water use by farms with meters. Another option comes with a bigger price tag: replacing canals with underground pipelines, which lose far less water and are better suited to serving cities.

Converting a mile of open-air canal into underground pipelines costs between $250,000 and $1 million, said Lambert, the irrigation district manager for Cameron County, which remains mostly rural. Her district has only been able to bring about a fifth of its 250 miles (402 kilometers) of canals underground in the past two decades, she said.

“It just gets to be an amount that could not be supported by the farming community,” Lambert said.

Since the early 1900s, a network of about two dozen independent irrigation districts have served the area’s farmers, cities and towns. But as McAllen gobbled up much of the farmland surrounding it, some officials have wanted more control over a water district they say charges the city too much for water deliveries.

Yet the higher rates charged to city water utilities are often how irrigation districts pay for canal repairs, said Fipps. That has meant the water districts serving bigger cities have generally made more progress in bringing canals up to date.

Still, the Rio Grande Valley’s water utilities and farms are linked by the same aging system.

Since cities and farms get water from the same canals, hydrologists and water officials say the Rio Grande’s shrinking flows and low reservoir levels could eventually spell trouble for everyone in a prolonged drought. When there’s little water in a canal, a greater percentage gets lost to evaporation or seepage. And everyone’s share of water is threatened.

Already, experts say demand for water from the river exceeds supply.

Small towns, which get relatively small water deliveries, could be especially affected during a severe dry spell, and their irrigation districts are less likely to have the money to repair or replace canals.

“This is an unusual situation, that the agricultural canals are used to help deliver the municipal water,” Fipps said.

Over time, experts say the region’s farms will face deepening water shortages and be forced to make more difficult choices, a scenario already playing out across parts of the American West. Some irrigation districts over the years have received state or federal funding through grants administered by the Bureau of Reclamation for repairs, but water managers, farmers and hydrologists say the money has been insufficient for comprehensive fixes. The Texas Water Development Board predicts that by 2070, water used to irrigate farms in the Rio Grande Valley will fall by 36%, in large part because more farmland will be replaced by urban development.

In rural Cameron County, Lambert is already seeing glimpses of that future. Earlier this year, before rain soaked the region, Lambert told sugarcane farmers in her district that they would only get one water delivery instead of two.

To salvage their thirsty crops, some farmers bought water from neighboring districts for tens of thousands of dollars. Others removed more than a hundred acres of the crop. A few weeks later, the skies opened up.

When farmers ask her how much water they can expect to receive the next season, Lambert says she often doesn’t have an answer.

“That’s the million dollar question asked by our farmers. And I have no earthly idea,” she said.


EDITOR’S NOTE — This is the third story in an occasional series looking at the interaction between population growth and climate change.


The Associated Press receives support from the Walton Family Foundation for coverage of water and environmental policy. The AP is solely responsible for all content. For all of AP’s environmental coverage, visit

Copyright © The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


FILE - In this Monday, Nov. 2, 2020, file photo, Stacey Abrams speaks to Biden supporters as they w...
Associated Press

2nd Stacey Abrams governor bid sees new tests, intrigues

ATLANTA (AP) — Stacey Abrams announced a long-awaited second run for Georgia governor this week, but with Democrats facing a sour national environment and Republican Gov. Brian Kemp facing challenges within his own party, the 2022 campaign will look different from 2018. Abrams’ narrow loss, highlighted by her claims that Kemp used his prior post […]
6 hours ago
FILE - Allen Toussaint performs at the New Orleans Jazz and Heritage Festival in New Orleans, Satu...
Associated Press

New Orleans: Push to rename Lee boulevard after Toussaint

NEW ORLEANS (AP) — A member of the New Orleans city council is pushing to change a street currently named after Confederate Gen. Robert E. Lee and replace it with one the city’s most famous musicians, Allen Toussaint, who died in 2015. Councilmember Jared C. Brossett introduced an ordinance to rename the street that goes […]
6 hours ago
In this courtroom sketch, defense attorney Jeffrey Pagliuca, left, confers with Ghislaine Maxwell a...
Associated Press

Scenes from Week 1 of Ghislaine Maxwell’s sex-abuse trial

NEW YORK (AP) — The first week of the sex-abuse trial of Ghislaine Maxwell saw the first of her four main accusers taking the witness stand to give emotional testimony accusing the British socialite of coaxing her — at just 14 — into sexual encounters with financier Jeffrey Epstein. The jury at the federal trial […]
6 hours ago
Dawn Neptune Adams holds a copy of the Phips Proclamation of 1755, Tuesday, Nov. 23, 2021, in Bango...
Associated Press

Penobscots don’t want ancestors’ scalping to be whitewashed

PORTLAND, Maine (AP) — Most Americans know Native Americans endured atrocities after the arrival of European settlers: wars, disease, stolen land. But it’s far uglier than that. Members of the Penobscot Nation in Maine have produced an educational film addressing how European settlers scalped — killed — Indigenous people during the British colonial era, spurred […]
6 hours ago
Pope Francis delivers his speech during a meeting with authorities, at the Presidential Palace, in ...
Associated Press

In democracy’s birthplace, pope warns of populist threats

ATHENS, Greece (AP) — Pope Francis warned Saturday that the “easy answers” of populism and authoritarianism threaten democracy in Europe and called for fresh dedication to promoting the common good. Arriving in Greece, the birthplace of democracy, Francis used a speech to Greek political and cultural leaders to address Europe at large about the threats […]
6 hours ago
In this photo released by Saudi Royal Palace, Saudi Crown Prince Mohammed bin Salman greets French ...
Associated Press

France’s Macron meets Saudi crown prince in final Gulf stop

DUBAI, United Arab Emirates (AP) — French President Emmanuel Macron met Saudi Crown Prince Mohammed bin Salman on Saturday for the final leg of a two-day Gulf tour. Concerns over Iran’s nuclear program, the multiple crises in Lebanon and the ongoing war in Yemen were expected to be aired in private by both sides. Earlier […]
6 hours ago

Sponsored Articles

Canvas Annuity

Annuity basics: how to retire with a guaranteed paycheck for life

Does the thought of retirement fill you with stress or with happiness? Everyone wants to spend their retirement in a way that brings them the most joy, whether that’s traveling the world or spending extra time at home with grandkids.
Arizona State University

Gain insights on next year’s trends at 58th Annual Economic Forecast Luncheon

Employment is recovering from the severe contraction induced by the pandemic, but it is still way below levels at the start of 2020. Can it fully recover in the coming year?
Sanderson Ford

Sanderson Ford offers cars and deals for all this holiday season

Sanderson Ford’s No! Vember Black Friday sale is giving an opportunity to purchase a new 2021 vehicle just in time for the holiday season.
In South Texas, aging water system meets growing population