Due to current drought conditions, Lake Austin will not be lowered this winter as originally planned.
The City of Austin submitted a drawdown request to the Lower Colorado River Authority (LCRA) in October, hoping that fall rains would increase water storage in lakes Travis and Buchanan and allow for an effective drawdown. However, as of Nov. 30, the combined water stored in the two lakes is around 1.1 million acre-feet — about 55 percent of their capacity.
Over the past decade, the lake has been lowered several times to control the aggressive non-native aquatic plant hydrilla. The last time the lake was lowered was in January 2008. The introduction of sterile grass carp into the lake by the City of Austin has had a major impact on controlling this weed. However, the carp have been less effective against other aquatic vegetation such as Eurasian watermilfoil.
“The lack of a drawdown is not the best case scenario for either property owners or lake users, but unfortunately, the persistent drought conditions are determining the situation,” said Mary Gilroy, Environmental Scientist with the City’s Watershed Protection Department. “While a drawdown would help minimize the impacts from the nuisance aquatic vegetation in shallow water, it would not have much effect on the aggressive hydrilla, which grows in much deeper water.”
“Reduced environmental flow requirements as a result of low lake levels and reduced winter water releases would not be enough to effectively draw down Lake Austin,” said Mark Jordan, Manager of LCRA River Management Services. “Even a very limited drawdown would not be effective for either vegetation control or dock maintenance and repair.”
The City of Austin continues to work with its partners (the Texas Parks and Wildlife Department, LCRA, and citizens’ group Friends of Lake Austin) to combat the invasive hydrilla, which showed resurgence to more than 320 acres this fall. Because sterile grass carp proved successful in reducing the aquatic weed in the past, the Texas Parks and Wildlife Department granted approval to stock an additional 4,400 fish. In mid-November, 2,200 fish were stocked, with the remaining fish scheduled to go into the lake later this year.
Contact: Krista Umscheid, LCRA, (512) 473-3365; Lynne Lightsey, City of Austin Watershed Protection Department, (512) 974-3538