Authority Lowers Lake Levels to Control Non-native Plant
The Lower Colorado River Authority began lowering Lake Austin Jan. 2, at the request of the City of Austin, Texas, to help control nuisance plants in the lake and allow lakeside residents to build and maintain docks.
The drawdown of the lake is expected to take between two and three weeks for Lake Austin to fall about 12 feet. The authority can only release the amount of water necessary to meet water demands and environmental needs downstream unless surplus water, sufficient to refill Lake Austin, can be stored in Lake Travis.
Without significant rain in the forecast, a slow drawdown is expected. However, if significant rains add sufficient water to the flood pool of Lake Travis prior to the beginning of the drawdown, then this water could be used to refill Lake Austin without impacting water supply, therefore allowing a faster drawdown and more time at the lower level. Officials will begin refilling Lake Austin on Feb. 8 and complete the refill on Feb. 13.
Lake drawdowns help control vegetation by exposing the plants to the air and killing off the leaves and stems by dehydration, providing temporary relief, particularly in shallow areas where the plants are exposed. Since hydrilla, a fast-growing water weed, was first discovered in Lake Austin in 1999, lowering the lake has been one component of an ongoing comprehensive plan to fight the non-native plant. Hydrilla has been less of a problem in recent years in Lake Austin; however, the presence of Eurasian watermilfoil, commonly known as duckweed, has increased.