Lake Travis, now 146 percent full, is being closely watched by officials deciding whether to open more floodgates on Mansfield Dam. If Lake Travis is forecast to rise to 710 feet, the Lower Colorado River Authority would have to consider increasing the flow of water downstream, raising the risk of flooding including along the shores of Lady Bird Lake in Austin.
Lake Travis is around 704 feet now, which has the LCRA believing it will not have to open more than the four floodgates currently streaming water into Lake Austin.
“We still have some flood protection, but we have to be very vigilant about how we watch what’s coming into the system and seeing what those projections are incase we have to adjust upward," LCRA executive vice president for water John Hoffman said.
“Rainfall is the great wildcard in all this, because if we see rainfall out in the watershed that results in runoff into Lake Travis, then we have to reassess our operations," he said.
Even with just four floodgates open, the release of water is causing dangerous currents. The city of Austin has banned recreation – including swimming and watercraft – on Austin's waterways, including Lady Bird Lake, Lake Austin and Lake Travis.
The National Weather Service forecasts the Austin area could get pockets of heavy rain on Saturday. Rainfall is expected to taper off on Sunday.
The governor has already issued a state of emergency in 18 counties, including Travis, after historic flooding in the Hill Country. Flooding along the Llano River damaged properties in Llano and Marble Falls and left one woman dead in Llano. That area is under a flood warning until tomorrow evening. Officials in Llano County cautioned those returning to their homes to remain vigilant as rains could cause additional flooding along the Llano River, which crested at 30 feet above flood stage earlier this week.
Correction: An earlier version of this story misidentified the Longhorn Dam.