Due to an unusually wet May and early June, many Central Texas lakes are now at or above normal elevations with runoff still flowing in, causing them to rise steadily. I interviewed Belton Lake’s Ranger Arty Johnson, who is employed by the U.S. Army Corps of Engineers.
Johnson shared the following responses to the questions posed to him concerning flood control and lake access.
As you read these responses, it is helpful to think of the USACE flood control reservoirs as ‘shock absorbers.’ Instead of water rushing downstream in a destructive, uncontrolled manner following heavy rains, reservoirs allow flood waters to accumulate and then to be released in a more steady, controlled manner so as to minimize flooding and associated loss of property or even life. Recreation is secondary to this primary purpose.
Just as a shock absorber can no longer absorb shock when it is fully compressed, it is possible for reservoirs to run out of water-holding capacity in extreme rainfall events like the one experienced in Central Texas in 1991 when both Belton and Stillhouse Hollow lakes reached over 100% capacity and water began to flow in an uncontrolled manner over the uncontrolled spillways intended to protect the earthen dams from destructive erosion.
Here are the questions posed to Johnson:
Q: In the past, USACE could discharge a combined maximum of 10,000 cubic feet second of water into the Little River from Belton, Stillhouse, Granger and Georgetown, yet several times this week, no discharge was taking place. What led to that scenario?
A: Ranger Johnson likened flood control to a juggling act. He shared how on Lake Belton, you have inflow from Proctor Lake which releases its flood waters into the Leon River which then flows into Belton Lake; you also have inflow from Cowhouse Creek and other intermittently running streams. Then, you have the quantity of water in Belton Lake itself, and finally you have the conditions of the Leon River, Little River and Brazos River downstream from Belton Lake to consider. All of these must be considered simultaneously. This week, downstream flooding on the Brazos River prevented a release of anywhere near the 10,000 CFS maximum permitted into the Little River.
If Belton takes in more than it releases, the water on Belton rises; conversely, if more water is released than is flowing in, then Belton falls. This week, to alleviate flooding conditions around Lake Proctor, and to prevent flooding downstream on the Brazos, Lake Belton’s gates were closed a majority of the time, thus the lake rose substantially.
Q. Is the information for Lake Belton shown at www.swf-wc.usace.army.mil/belton/ up-to-date so the public can answer their own questions about access?
A: Yes, the information is up-to-date as of close of business on Fridays, however, USACE office staff is not present over the weekends, and the rangers on shift are working in the field during that time.
Hence, there is potential for the situation on the ground not to match the situation reflected on the website until a comprehensive update is done on Mondays.
Q. Is there anything you would like me to share with the public on the USACE’s behalf concerning the current situation?
A: USACE wants to remind those recreating while Lake Belton is flooded to exercise caution. Flotsam will be present in areas where there normally is none due to debris being carried into the lake by flood waters. We urge people to wear their life jackets, take a means of communication with them in case an emergency arises, to use a buddy system to keep a lookout on others in their party, and to use smartphone technology to keep an eye on the weather forecast.
Ranger Johnson went on to verify the accuracy of information previously provided by USACE Lake Manager Ronald Bruggman while he still served in that capacity.
Q. Does the Corps have any predictive tools or measuring/detection devices that allow it to predict future hourly or daily inflows into Belton and Stillhouse based on rainfall in the watershed?
A: USACE partners with the US Geological Survey in maintaining river gauges to monitor flows of major tributaries. These gauges report every 15 minutes. During flood conditions, we monitor these gauges and also work with the National Weather Service to perform forecasts on predicted lake levels.
Q. Is there a “magic number” concerning elevation at which all boat ramps on Belton will be closed? And what is that elevation for Stillhouse?
A: There is no magic number. We manage a combined 20 boat ramps on these two lakes, and each ramp is at a little different elevation. We hold off on closing these ramps until after the water is over the ramp and covering the turnaround. At that time, there is really no way to safely launch. Most of the boat ramps at Belton Lake are nonfunctional when the elevation is between 599-606 feet above sea level.
We do have a concrete roadway that is at reasonable gradation to allow boat launching in Belton Park to reopen once we hit an elevation of 611 feet. There are a few other access points/boat launch around Belton that are managed by others that may be open. For Stillhouse Lake, generally speaking, the boat ramps are nonfunctional between elevations of 628-637 feet above sea level.
Q. As one looks at USACE data about the volume of water being released during times of flooding, there are oftentimes several lakes releasing high volumes of water, like Possum Kingdom and Granbury, while Stillhouse and Belton’s gates are shut. How does the Corps prioritize when to release water and where water is released from?
A: The lakes like Possum Kingdom, Granbury and Limestone are owned and managed by the State of Texas and were not constructed for flood control purposes, therefore flood waters pass through. The USACE must factor in these free-flowing bodies of water when they calculate how much water may be released from USACE-managed flood control reservoirs like Belton, Stillhouse, Granger, and Georgetown.
Q. If boat ramps shut down, can anglers expect to have access to the area boat ramps as soon as the waters recede?
A: The boat ramps will open once the flood waters are below each turnaround for at least 10-14 days.
After the roadways are inundated with water, the road base under the roads must dry before allowing traffic on them. If not, the base will move and ruin the asphalt surface. Roads are very expensive to replace/repair.
The USACE Belton Laek office phone number is 254-742-3050.