By Marty Kufus

Local ground-water officials are angry over San Antonio’s “short-term” plan to pump billions of gallons from a small portion of the Carrizo Aquifer in southern Bexar County, saying it could harm shallow wells nearby in Wilson and Atascosa counties. The issue arose last week at a meeting of the Evergreen Underground Water Conservation District. It appears to be headed to the regional water-planning group. Spokesmen for the San Antonio Water System, however, quickly called it a misunderstanding over their aquifer storage and recovery (ASR) test project. “We value the Evergreen’s relationship highly,” SAWS engineer Mike Brinkmann, a technical spokesman for the ASR project, said Thursday. SAWS public-relations officer John Boggess agreed. He termed the planned pumping “short-term production.” It is planned to help meet San Antonio’s needs during several years’ testing of ASR, Brinkmann said. The pumping of SAWS’ Carrizo wells in extreme southern Bexar County will begin in 2004, last through 2007, and produce up to 30,000 acre-feet of water a year, he said. At about 325,860 gallons per acre-foot, that equals some 9.78 billion gallons a year maximum. Consulting engineers’ research suggests that figure is a “sustainable yield,” Brinkmann said. The pumping would occur during “cycle testing” in six of the 17 wells in the ASR project, Brinkmann explained Thursday. Edwards Aquifer water will be injected into the Carrizo, stored, then withdrawn in efficiency tests.

There is no ground-water district in extreme southern Bexar County. SAWS has bought about 3,200 acres there for its ASR project. Just across the line, the Jourdanton-based Evergreen district has legal jurisdiction in Wilson, Atascosa, Karnes, and Frio counties. SAWS’ goal in the ASR project is the wet-season injection of a large amount of surplus Edwards water hundreds of feet below the surface in the Carrizo Aquifer. The chemically distinct Edwards water would be pumped back up later to meet SAWS customers’ peak summer demands. A San Antonio Express-News article earlier this month, quoting SAWS board Chairman Juan Patlan, apparently was the first clue Evergreen officials had of the planned pumping of the Carrizo in southern Bexar County. “I thought they [SAWS’ representatives] were real honorable people — up to that point,” Evergreen President Kenneth Stephens said Feb. 20 at a board meeting. SAWS and the Evergreen officials have discussed possible cooperation in a future expansion of ASR into Wilson and/or Atascosa counties (March 22, 2000 Wilson County News). Stephens and other board members indicated last week that future cooperation in SAWS’ ASR project is unlikely now. “This [pumping] was not part of the regional water plan,” Mike Mahoney, Evergreen’s general manager and a regional planner, added with irritation. Mahoney told his board and concerned Evergreen patrons at the meeting that he would raise this issue at the March meeting of the South Central Texas Regional Water Planning Group.

The “Region L” plan, submitted last month in Austin, includes municipal and regional ASR projects — in general form. ASR projects already are being operated successfully in Kerrville and El Paso and at several locations around the United States, Brinkmann said. SAWS estimates its project will cost $216 million altogether. That includes the construction, by fall 2003, of pumping stations and pipelines connecting with the existing municipal water system. He said SAWS’ consulting engineers at the firm of CH2M Hill Inc., will continue using computer simulations to project the pumping’s possible “draw down” — lowering of water levels — in the area. Brinkmann said he did not yet have figures on possible “draw down” in neighboring wells for the 2004 to 2007 period. Using state-developed computer models for aquifers, he explained, CH2M Hill projected the Carrizo’s pumping across 50 years, factored in the additional 30,000 acre-feet, and concluded it would be a “sustainable yield.” Some of the neighboring residents in Wilson and Atascosa counties might not actually have wells in the Carrizo, Brinkmann added, but in minor aquifers: the Sparta, Queen City, or Reklaw. “People sometimes think they’re in one aquifer, but they’re in another,” he said. In the Carrizo-Wilcox Aquifer system, he added, “aquifers lay on top of each other like a layer cake.” SAWS will have to obtain a permit from the Texas Natural Resource Conservation Commission before it can inject water into the Carrizo Aquifer. In the coming years, the Edwards Aquifer Authority will enforce gradually reduced pumping of that aquifer, forcing SAWS to look for additional water sources. Costly pipeline projects to bring water to San Antonio from the lower Colorado River and from just above the Guadalupe River’s saltwater barrier are 10 years or more away, according to the regional plan.