WATER SECURITYTexas’ Plan to Provide Water for a Growing Population Ignores Climate Change

By Erin Douglas

Published 1 November 2022

Texas’ biggest single solution to providing enough water for its soaring population in the coming decades is using more surface water, including about two dozen new large reservoirs. But climate change has made damming rivers a riskier bet.

This small South Texas border community 200 miles southwest of San Antonio hugs one of the largest reservoirs in Texas, along what was once one of the nation’s mightiest rivers. But on a hot summer day in mid-August, Zapata was dangerously close to running out of water.

Joe Rathmell, the Zapata County judge, remembers getting the call from a worried water plant manager. It wasn’t good. The only thing flowing into the county’s intake station seemed to be mud. The pumps were failing as they struggled to suck the silty water from Falcon Lake.

“We had what I would argue was the worst water along the whole [Rio Grande],” Rathmell said.

This summer, as Texas baked — the hottest July on record fueled its worst drought in a decade — water levels in reservoirs across the state fell dramatically, prompting hundreds of mandatory water restrictions.

By late October, water storage in Texas reservoirs had fallen to 67% of capacity, down from 80% a year earlier, according to state data. Reservoirs on the Rio Grande saw their lowest levels in decades in August — Amistad Reservoir dropped to 30% of capacity, its lowest level since 1998, while Falcon Lake, about 50 miles south of Laredo, dropped to 9% of its capacity, the lowest level in two decades, before rebounding slightly after heavy September rains.

Zapata County, desperate for water, requested money and equipment to dredge the mud away from its intake station. The federal government gave $2 million to help and the local congressman, Rep. Henry Cuellar, D-Laredo, hosted a celebratory press conference when the dredging equipment arrived.

But it was a temporary fix for a long-term crisis: Climate change has brought higher temperatures that dry soil more quickly, enhancing the effects of drought and causing less rain to flow into Texas’ rivers and streams. At the same time, longer-lasting and more intense heat brought by climate change accelerates water evaporation from Texas’ reservoirs.

“It’s not going to go away,” Rathmell said. “Over the years, our area does seem to be getting drier. It seems like it rains less year after year.”

“And of course,” he added, “the demand for water just keeps increasing.”