WhoopingCrane_BaseFlowCapture_Henry_Stuart_AustinTX_18June1999_Reel2008.wav

Stuart Henry [00:00:00] A lot of the reservoirs in Texas, due to recent developments, rely on groundwater supplies, as well as surface water. There are probably 70% of the rivers in Texas, at base flow, rely on groundwater discharges.

Stuart Henry [00:00:25] Now, in the old days, old days being prior to 19, late 50s, when you built a reservoir, you could not impound the natural flow of the river. You only were allowed to impound the river flow, the flood flows.

Stuart Henry [00:00:41] The reason was that, was that you had to pass through, you couldn't dry up a river. You had to pass through the base flows.

Stuart Henry [00:00:50] Well, it had a good environmental reason, although they never used it. I mean, they never thought about it in that way. And that was because you could not assure, with Texas Rule of Capture, you could not insure over any length of period of time with those base flows, because those base flows were coming from groundwater exiting in the rivers and creeks.

Stuart Henry [00:01:11] Well, we've now got areas that we've got reservoirs that relied on that, in fact captures the base flow and so-called "appropriates" it. That those surface water reservoirs are not going to have near as much water in it as they think, because they're capturing not only flood flows, but base flow.

Stuart Henry [00:01:34] Very good example is Waco. I mean, like Brazos River Authority, Lake Waco. Another good one is, for example, Guadalupe-Blanco River Authority. Sixty percent of the base flow of the Guadalupe River, at the entrance to the estuary, comes out of those springs. GBRA I knows that. Victoria's water depends on those spring flows.

Stuart Henry [00:02:03] Well, I'm going to tell you what: in the '50s, there was only one river running in this state that was west of IH-35, and that was the Guadalupe. And it was running at the lower part of the river.

Stuart Henry [00:02:16] And that was due to the springs.