Rains of up to more than eight inches in Kingsland and surrounding areas Wednesday evening and early today have resulted in the Lower Colorado River Authority opening floodgates at Wirtz and Starcke dams upstream of Austin.

The floodgate operations are necessary to pass along runoff from Sandy Creek, which at 2 a.m. today was more than five feet above flood stage near Kingsland.

As of 2 a.m., three floodgates were fully open and two floodgates partially open at Wirtz Dam, which forms Lake LBJ, to handle the runoff.

Downstream, nine floodgates were open at Starcke, with a 10th gate expected to open shortly.

The dams are passing more than 100,000 cubic feet per second, which will flow into Lake Travis. North Grape Creek, a tributary to the Pedernales River above Johnson City, is discharging about 18,000 cubic feet per second, which also will flow into Lake Travis.

Lake Travis has risen only about a third of a foot since Wednesday but is expected to rise at more than a foot per hour later this morning as the inflows reach the lake. The duration and total amount of the rise will depend on continuing rainfall patterns.

Upstream, Inks Lake was about two feet over its spillway. That lake has no floodgates.

No floodgate operations are expected at the other Highland Lakes dams: Buchanan, Mansfield or Tom Miller.