With each issue, Trib+Water brings you an interview with experts on water-related issues. Here is this week's subject:
Steve Young is a principal geoscientist at Intera, a geoscience and engineering consulting firm in Austin. Young focuses on groundwater issues and how to solve them.
Editor's note: This interview has been edited for length and clarity.
Trib+Water: There was an article in the San Antonio Express-News that said you were at a symposium asking if there is enough water to support Central Texas. Is there enough water to support Central Texas?
Steve Young: The short answer is that over the next 50 years there is enough water in the Carrizo-Wilcox Aquifer to supply the growth needs based on the state water plan. But you have to be careful where you withdraw that water.
The water has different pumping impacts depending on if you pump from the shallower part or the deeper parts or where rivers are near it or existing wells. The key part of that whole puzzle is being able to withdraw from areas that would minimize the impact and to monitor those impacts as they accumulate in the area where you pump over time to make sure that you minimize the impact.
The current plans that you might see don’t necessarily look at that whole equation.
Some of the areas they’re pumping might not be some of the best areas. But that’s sort of a different question because some of the areas they pump is to minimize the cost to deliver the water. You really should be looking at cost, not to minimize the cost to the user but also to minimize the impacts where the water is coming from. So if you look at both of those, you can make it work, but that whole puzzle hasn’t been solved yet.
There is enough water in the short run.
Trib+Water: Does that take into account population growth from Austin and San Antonio?
Young: Yeah, that’s what the state water plan does. … They can supply that kind of population, but you have to be aware that you can’t pump anywhere in that aquifer. You have to be careful of where you’re pumping to minimize the impacts.
They really should be pumping into deeper parts of that aquifer where there are relatively few wells and you won’t be getting groundwater to surface water impacts and you won’t be impacting other wells.
This is not indefinite. This is talking about the next 30, 40 years; the water is there to supply it. After that, they will have to reassess and look for alternative schemes.
Trib+Water: What can we do now to ensure there is enough water in the future?
Young: These big cities — San Antonio excluded — most of them are relying on surface water. Surface water rights are already tied up so they go looking for other sources. And that’s where you get into the groundwater away from cities because that water has not been spoken for.
The first act that we have to be looking to do is to maximize the firm yield of these surface water systems. There are a couple ways to do that.
One is to look at off-channel storage. You’re looking at small reservoirs off channels located near key distribution locations. They’re also looking at inline detention dams; just a small way to raise water to capture a little bit when it rains excessively.
A huge area that needs to be looked at is conjunctive use between groundwater and surface water. When you have excess surface water flows … some of that water should be skimmed off. That’s when you skim it off channel, but you should also be putting it into the ground and recharge, that’s aquifer storage and recovery. It’s a great way to capture water that is available that would otherwise be going to the coast or high flows. You capture it, put it into the ground and go back and pump it when there’s low surface water availability.
It really comes down to better use of capturing water during high flows in the river. You put it into off channels or put it into the ground. You come up with better permits for pumping groundwater so they can easily get a permit and say they’re not going to pump it all the time. They’ll pump it during low surface water flows to … meet the needs of that surface water system that will go a long ways to reduce the need on groundwater.
Trib+Water: If I’m a homeowner, what can I do? Is there anything I can do to help out?
Young: Be aware of what your groundwater conservation district is doing locally. Typically, they have monitoring programs so it’s nice to provide information from your well to the district. Either have them come out and monitor it through water samples or water levels; it helps to better understand the aquifer. There’s always a shortage of having good monitoring implementation and understanding how it’s changing.
The other one is to minimize watering your grass. Conservation of water is a key issue, and minimizing grass watering that’s one of the largest sources of residential use ... is discretionary.
Trib+Water: So maybe something like homeowners switching to Xeriscaping would be a good option to cut down on their water use?
Young: Oh, yeah, that would be. That’s the conservation of water and reducing lawn water. That’s a huge issue actually.
Trib+Water: What are the big water problems facing the state? Are they similar to what Central Texas is facing or is the state so big that each area is different?
Young: The fact is that a lot of the easily accessible water has really been tied up in surface water. Most of these rivers now are fully allocated. There really is limited water from these rivers to give to industries. So they have to find alternative water sources.
You’re looking at developing the science and technology to understand how to develop those alternative water sources. Some are water storage and recovery … the other is developing brackish water resource.
Brackish is where you have a high dissolved solid concentration … but to develop the technology to treat that and bring the salt level down to make it drinkable at an affordable level.
Looking at better integrated plans among populated cities so they can better cooperate for regional water planning … and to share resources is an important area we have to improve on.