Is Rain the Answer to Texas’ Water Problem?

Opponents of groundwater mining say we have to declare a moratorium on growth. But what if growth itself actually created water?

By Dennis FoleyAugust 10, 2015 8:44 am

This story is an excerpt from the audio documentary Our Desired Future, a multimedia project to educate Texans on the interconnections between water above and below ground and what Texans can do to keep water flowing for future generations. You can listen to the full documentary here and read the stories here.

Water shortages, we often hear, will be the thing that brings the growth machine of Texas to a grinding halt. Our reservoirs hold only as much water as lands in their catchment, and our groundwater basins are holding less and less as we pump more and more to keep up with our growing demand. Proponents of groundwater development tell us to drill deeper. Opponents of groundwater mining say we have to declare a moratorium on growth. But what if growth itself actually created water? In other words, what if rain follows the bulldozer?

The idea sounds farfetched, but as it turns out, there is a resource that could actually increase the amount of water available to us, one that people have relied on for as long as there’s been a place called Texas.

That resource is rain.

All water in Texas starts as rain, whether we pump it out of the ground or siphon it from a river. Rainwater harvesting relies on neither of those methods—it is, instead, the practice of capturing and storing water as soon as it falls from the sky. By siphoning rainwater into storage tanks as soon as it lands, we expand our net water budget. Here’s why: for every drop of water that infiltrates into the ground or flows into a reservoir, there are 9 drops of water that either evaporate or are sucked up by plant roots and transpired into the atmosphere.

Rainwater harvesting taps into the 90% of rainfall that is never made available for human use when we rely on groundwater or rivers. Although the practice has been around for thousands of years, and has been a mainstay of rural Texans where wells were unreliable, it is only now being rediscovered by most of us who grew up reliant on municipal supply.

Julie and Larry Swofford live in Dripping Springs, around the corner from one of the subdivisions transforming this scrubby Hill Country region into a bedroom community for Austin. The Swoffords live entirely off the water collected from their roof. They weren’t looking for a rainwater-fed house—it just kind of found them.

“It took us a long time to find this house,” said Julie, “but it had all the things I really liked, and it had this rainwater system and I thought, that’s okay.”

Larry was a little more skeptical: “It was a concern because the house doesn’t have a well, it doesn’t have city water, it only has rainwater. And I was sitting there saying, okay, well, I’ve always wanted to go off grid if I could, and this sounds interesting, but I just didn’t know if it would be enough to sustain us.”

The Swoffords moved into their rainwater-fed house right in the middle of the drought that started in 2009. Having never lived off rainwater before, Larry had his fair share of sleepless nights worried over whether they would run out of water.

Our Desired Future is a project of the Texas Center for Policy Studies and funded in part by a generous grant from the Shield-Ayres Foundation.