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McALLEN — South Texas was prepared for a deluge.

City officials distributed sandbags and planned road closures. Gov. Greg Abbott declared a state of disaster before Tropical Storm Alberto, which was projected to dump up to eight inches of rain in the Rio Grande Valley.

But by the time the storm passed, the four-county region in the southernmost part of Texas only saw about half that. The shortfall was good news for residents concerned with flooding. And yet, it was hardly enough to raise the level of water in two reservoirs that serve the millions of people along the Texas-Mexico border.

The levels at the Amistad International and Falcon International reservoirs remain near or at record lows. The lack of water threatens the region’s agricultural industry and residential users alike. Earlier this year, the last sugar mill in Texas announced its closure after 50 years due to water scarcity and local agriculture leaders worry citrus could be next.

The Falcon reservoir is at approximately 11%. The reservoir saw a slight uptick from a record low of 8.8% on May 28 partly thanks to the rains from Alberto. Meanwhile the Amistad Reservoir, which did not receive much rain, is at a record-breaking low of about 19% as of Monday morning, according to Barry Goldsmith, a meteorologist from the National Weather Service in Brownsville.

The low water reserves are partly due to the lack of water deliveries from Mexico that are required under a 1944 treaty between the two countries. Mexico is required to deliver water to the U.S. from six tributaries that feed into the Rio Grande. In exchange, the U.S. delivers water from the Colorado River to Mexico.

[U.S. Supreme Court blocks the state’s Rio Grande water deal with New Mexico]

But Mexico's own drought has led the country to fall behind on its deliveries, raising doubts about whether it will be able to release the 1,750,000 acre-feet of water it is required to by the end of the current five-year cycle which ends in October 2025.

Without water from Mexico, farmers are hoping for an especially active hurricane season and there is reason to be hopeful.

This year's tropical forecast has an above average number of weather events such as storms, hurricanes and major hurricanes.

Currently forecast are 17 to 25 named events, which are tropical storms or higher, eight to 13 hurricanes and four to seven major hurricanes which have winds of 111 miles per hour or higher.

It's too early to know how many of those storms Texas may see. And odds that the Valley will be directly impacted by one of them, while double what they normally are, are only 5.8%, Goldsmith said.

If rain does land on the region, the amount needed to raise the water at the reservoirs to levels considered normal will take a major storm like one the Valley experienced in 2010.

Almost exactly 14 years ago, the region found itself in a similar situation with the reservoirs reaching what were then considered historic lows. The area received much needed rain from Hurricane Alex which hit South Texas in late June 2010. The hurricane brought at least 50 inches of rain and prompted the opening of the floodway.

"That would not happen right now if another Alex came in," Goldsmith said. "That's how low we are that the reservoirs would be able to take in all that water."

Smaller, multiple events could add up over time, but the best hope for significant gains is a hurricane like Alex which might bring the reservoirs back to 50%.

"The difficulty right now is that we're relying on a hurricane Alex-type event or multiple hurricane Alex-type events, to get the reservoir back to some semblance of normalcy," Goldsmith said.

While Tropical Storm Alberto didn’t bring quite the downpour that was expected, the few inches of rain helped to refresh the soil which is helpful to the citrus trees, cotton, the hay fields and the pasture in the area, said Brian Jones, a local farmer and a state director for the Texas Farm Bureau.

"It doesn't alleviate any of our water woes by any means,” Jones said. “But it does put some moisture back into the soil."

The moisture has provided some breathing room but if the irrigation water used for farming continues to be scarce, the agricultural industry could suffer another blow like the end of the sugar cane industry.

Already this year, about 6,000 acres of citrus have been bulldozed. Countless citrus trees sit in greenhouses waiting to be planted. Citrus trees are especially reliant on water because they need the moisture to produce a crop on top of the water they need to stay alive.

"The companies are not willing to take that risk right now knowing there's no water in the dams," Jones said.

Agriculture might be experiencing the biggest losses but municipalities are also being affected.

Most cities rely on irrigation districts to deliver their water to them, as municipal water rides on top of irrigation water to get to their delivery point.

Without irrigation water, it becomes nearly impossible for municipal water to be delivered without something pushing it, or what is called push water, according to Sonny Hinojosa, a water advocate and former general manager for Hidalgo County Irrigation District No. 2, which supplies untreated water for agriculture and contracts with municipalities for the delivery of water.

Municipalities find push water to deliver their water to them but as supply dwindles, push water may not be available for purchase.

Relying on push water can also become inefficient and already has for some water districts, which are using two acre-feet of push water just to deliver one acre-foot of water.

"You're losing water just trying to push that small amount of municipal water to their delivery point," Hinojosa said.

When water is plentiful, cities pay a fraction of an acre-foot of water for every acre-foot delivered.

"In situations like this, a city's municipal water supply could run out if they're being charged the full amount of what it actually costs to get them the water to their delivery point," Hinojosa said.

Reporting in the Rio Grande Valley is supported in part by the Methodist Healthcare Ministries of South Texas, Inc.

Disclosure: Texas Farm Bureau has been a financial supporter of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune's journalism. Find a complete list of them here.

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This article originally appeared in The Texas Tribune at https://www.texastribune.org/2024/06/25/south-texas-rain-water-levels-tropical-storm-alberto/.

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