Behind Texas's Looming Crisis: Groundwater Scarcity

By Forrest Wilder, Texas Observer. Posted May 19, 2009.

Adding to the system's complexity, some of that Trinity water -- about 64,000 acre-feet per year -- moves underground into the Balcones Fault Zone portion of the Edwards Aquifer, the source of the perennial San Marcos Springs. Those springs are the headwaters of the San Marcos River, a main source for the Guadalupe River in times of drought.

Texas water law recognizes very little of this. As a drop of water moves between the ground and the surface, it passes through two different legal spheres. As surface water, it's owned by the state but perhaps allocated, in the form of a water right, to a rancher, farmer, or city. As groundwater, it's the property of the landowner.

Jacob's Well confuses this artificial distinction. The spring is not just a headwater; it's literally a spy hole into the Trinity Aquifer. Divers have mapped the underwater cave over a mile underground, pushing through a series of chambers deep into the limestone Cow Creek formation of the Middle Trinity. Eight have died in the pursuit of the unknown.

"Jacob's Well is the expression of the aquifer on the surface," Baker says. "What it's indicating to us is that the whole system is stressed."

Recent research suggests that Jacob's Well is highly sensitive to pumping, especially in the recharge zone northwest of the springs, an area of small sinkholes (believed to connect to Jacob's Well) and cedar-choked hills that developers are carving into residential lots. The main development is called The Ridge at Wimberley Springs.

"I think we've reached the limit, yet more homes are going in as we speak," Baker says. "And that's the dilemma."

Since founding the Wimberley Valley Watershed Association in 1996, Baker has been fighting to keep developers from chewing up Jacob's Well. At the moment, the watershed association is tied up in a lawsuit with a group that wants to build RiverRock, a "residential resort" -- spa, "lagoon-style" pool, gourmet restaurant -- a few hundred feet from Jacob's Well. RiverRock wants to build a road through the Jacob's Well Preserve. Baker hopes to stop the development altogether, claiming that it would pump 15 million gallons per year, which could have a direct impact on flows at the springs.

Baker is also at loggerheads with Aqua Texas, a for-profit water utility that serves Woodcreek, an incorporated subdivision of 1,500 people just south of Jacob's Well. Last year, almost half the water Aqua Texas pumped from its main well was wasted because of crumbling infrastructure. Worse, when the company turns on the pumps at that same well, the discharge at Jacob's Well drops a corresponding amount.

In 2005, the watershed group scored a victory by consolidating the four parcels of private land that abut the spring. With a $3 million grant from Hays County, the group is creating the Jacob's Well Preserve, a 55-acre natural area that eventually will be open to the public.

This effort will be for naught if something isn't done to manage the Trinity. Hays County is one of the fastest-growing counties in a fast-growing state. In 2000 the population was a little under 100,000; in 2060, it's expected to reach 500,000. In the past few years, the county has been the scene of intense squabbles between anti-sprawl activists, drawn largely from the Wimberley area's large retired population, and pro-growth interests.

Add water to the mix. The Trinity Aquifer, which is much less rechargeable than the Edwards, provides the vast majority of groundwater for the area. "There's a lot of straws pulling from an aquifer that doesn't have a lot to give," says Ron Fieseler, the coordinator for Groundwater Management Area 9, which covers a swath of the Hill Country.

Geologists say pumping in western Hays has already passed the limit of sustainability. Computer modeling by the Texas Water Development Board predicts water-level declines during a severe drought of between 50 and 100 feet across the Trinity, including portions of Bexar, Travis, Kerr, Hays, Blanco and Bandera counties.

What would that mean? Hays County got a small taste in 2006. Drought, compounded by overpumping, left about 100 homes near Dripping Springs without water and reduced Onion Creek, which flows through Hays County and South Austin into the Colorado River, to a trickle. A report on the '06 drought by Austin hydrologist Raymond Slade warns of the consequences of a far worse drought, which "will cause many more wells to become dry and probably result in many thousands of people in the County to be without water. Nobody knows when this will happen but it is likely to occur in the near future." Onion Creek, he concludes, is likely to stay dry except when there's significant runoff from storms.

See more stories tagged with: texas, water, drought, water scarcity, groundwater

Liked this story? Get top stories in your inbox each week from Water! Sign up now »