Public safety officials and researchers at the University of Texas at Austin have unveiled a new national flood prediction system, which researchers say will increase the amount of river and creek flood forecasts by more than 700 percent and offer a new approach that will save lives in Central Texas and beyond.
The system takes information on rainfall, geography, streamflow data and more, and runs it through sophisticated computers to forecast floods up to 15 hours before they hit. With that kind of lead time, officials hope to warn and, if necessary, evacuate more people.
The driving force behind the work has been Prof. David Maidment, a hydrologist at UT Austin who, in conjunction with the National Weather Service, developed the model.
It’s a model, he says, that’ll bring about more efficient, predictable evacuations. Maidment says it will augment more traditional flood warnings, like word of mouth. In Wimberley, for example, a so-called “old timers' network” of residents along the Blanco River call officials to warn of impending floods.
“They ordered the evacuation based on one phone call from a rancher in May,” Maidment says. “For goodness sake, imagine if that guy hadn’t called. That moved 1,000 people out of harm’s way. That’s a sobering thought.”
While the old timers' network has its merits, the new system would increase surface flow data from streams.
“Basically we’ve now got the capacity to be able to measure about one one-hundredth of the number of streams that exist in the country,” Maidment says. “In other words, for every one that we measure, there are 99 that we don’t. And basically we're going to calculate the other 99 instead of having to measure the whole lot.”
For example, right now in Travis and Hays County there are six locations where the National Weather Service has the potential to forecast flooding. Using the new approach, there will be 784.
At U.S. Hwy 183 and Onion Creek there are 110 so-called “reaches,” the lengths of a creek contributing to its flow. Similarly, the Blanco River above Wimberley has one forecast point, but 130 reaches.
Under the new system, those reaches would be measured, allowing for more accuracy in flooding predictions by expanding forecast points from approximately 3,600 to 2.67 million.
Maidment says that extra data will provide a fuller picture of potential floods, and it will do so in a fraction of the time it currently takes. The system will go live at the National Water Center in May of Next Year.
