Lake Austin Floodgate Operations Halted

May 27, 2015by Brian Talley

Tom Miller Dam Lake AustinFloodgate operations for Tom Miller Dam on Lake Austin were briefly enacted this week, as record-breaking rains fell across the Highland Lakes region. Floodgate operations have since been halted.

Lake Austin is the Austin area’s constant level lake, while lakes upstream fluctuate. Lake Austin’s normal depth is approximately 75 feet, or 492 feet above sea level.

According to an Austin American-Statesman article, “About 2.5 billion gallons of water rushed into Lake Austin through creeks and rainfall, about five times the lake’s limited capacity for extra water.” For about four hours, that water was released by hydroelectric generation into Lady Bird Lake, which was also receiving floodwaters from Shoal, Barton, and Waller Creeks. The Longhorn Dam on Lady Bird Lake was made operational in order to reduce that overfill.

Lake Austin marinasLake Travis, which feeds into Lake Austin when full, has risen approximately 30 feet over the course of the month. Its level was 629.5 feet on May 1 and stands at just over 658 feet at the time of this post. Its full pool is 681 feet. Only slight increases are expected in the near future, barring any additional large rain events, and no overflow releases are planned from Mansfield Dam at this time.

Floodgate operations at Wirtz Dam at Lake LBJ and at Starke Dam at Lake Marble Falls also have been halted. Debris is still a factor for all lakes.

Especially since area creeks are swollen and area grounds are saturated, conditions can change quickly. See current lake levels and dam operations.