Splashing around in the Llano River is a nice way to spend a hot summer day, but LCRA hydrologists Steve Salinas’ and John Roberts’ daily forays into the water are more than play.
Salinas and Roberts are among a handful of LCRA employees who spend their days measuring the amount of water flowing in the Colorado River and its main tributaries. The information is vital for communities, LCRA water planners, and others dealing with the current drought, just as it is during flash floods that can send torrents of water tearing down the river. The measurements can determine how much water LCRA must release through its dams for the downstream environment or help a local community determine if it needs to increase water conservation efforts.
The City of Llano, for instance, recently went to stage 3 watering restrictions, which limits outdoor watering to a maximum of one day a week. Llano works closely with LCRA to measure the flow on the Llano River.
“All of our water conservation and drought contingency planning is based on the flow of the river,” said Llano City Manager Finley deGraffenried. “The flow triggers us going into more strict or lenient conservation measures.”
The lower Colorado River runs 600 miles, dissecting Central Texas and the Hill Country on its journey to the Gulf of Mexico. Along the way, it can pick up water from numerous smaller rivers, streams, and creeks that can spring up when it rains. The watersheds feeding the lower Colorado River encompass a massive area nearly as large as the state of West Virginia.
For well over a year, of course, many of the tributaries have been dry or reduced to a trickle much of the time by the persistent drought plaguing the region. Even when it has rained this year, many of the storms have been downstream of lakes Travis and Buchanan, the region’s reservoirs. Or, the rains have come after long dry spells and most of the water has simply seeped into the ground rather than run off into the tributaries that feed the Highland Lakes.
LCRA has a system of 262 measurement stations throughout the region, some of which it shares with the U.S. Geological Survey, to measure the flow of the Colorado River and its tributaries. The information is fed to LCRA’s River Operations Center and posted on LCRA.org on the Hydromet page, a popular destination for those who like to or need to keep track of river and water supply conditions.
“It’s just an incredibly useful tool for people that rely on water,” deGraffenried said. “We’ve also educated our citizens and our council that this is a great tool. There is more recognition and our citizens are savvy about the river flows and what it means to the town.”
The automated, high-tech equipment at the measurement stations can only do so much on its own. It’s up to about a dozen hydrologists to hike the river banks throughout the watersheds, checking the equipment and taking manual measurements to make sure the readings are accurate.
“We need to know how much water is flowing into the lakes so they (water planners) can make decisions,” Roberts said. “We monitor that daily and make sure our equipment works.”
This work entails using a Doppler flow meter mounted on a 4-foot pole to collect data from the river, including the velocity, depth, and temperature of the water. Roberts and Salinas both graduated from Burnet High School in the late 1980s and have been friends for more than 30 years. This comes in handy, they said, when spending long days tromping around the river and braving the elements to gather data and check equipment.
During floods, when rivers are raging, the work can be dangerous. During the current drought, the water may be barely ankle deep, making snakes, wasps, poison ivy, and heat the biggest obstacles. Ultimately though, the hydrologists said their greatest satisfaction comes from helping ensure that there is water in times of drought and that people are kept safe during a flood.
“A lot of people just assume that you go to the faucet and turn it on and that’s the way it works,” Salinas said. “But it’s a lot more complicated than that. The data we collect from the labor we do helps in that, and it’s nice to know that we had a hand in it.”