The Lower Colorado River Authority opened a floodgate at Mansfield Dam on Lake Travis April 25 at 8 a.m. It was the first time a gate at the dam has been open since 2007.
According to LCRA officials, the agency begins floodgate releases—under the direction of the U.S. Army Corps of Engineers—when the elevation of Lake Travis exceeds or is projected to exceed 681 feet. As of 1:15 p.m. today, the level of Lake Travis was at 684.12.
Karina Medina of Steiner Ranch and son Stefano Bonilla join the crowds taking pictures of the open floodgate at Mansfield Dam. The last time a floodgate opened at the dam was 2007.[/caption]
"USACE protocols determine how much water LCRA may release, depending on how much water is in the Lake Travis flood pool and downstream conditions," an LCRA news release stated. "Releases from the dam generally increase when Lake Travis is projected to rise to higher levels. However, releases may be halted or reduced, depending on flood levels measured at three river gauges located downstream of the dam at Austin, Bastrop and Columbus."
Water was not flowing over the Mansfield Dam spillway. Water would flow over the Mansfield Dam spillway in an uncontrolled release if the level of Lake Travis rises above 714 feet, the release stated.
Floodgates were open at Buchanan, Wirtz, Starcke and Tom Miller Dams as well, with the floodgate flow at Tom Miller Dam increased to accommodate the heightened flow entering Lake Austin upstream from Mansfield Dam, the release stated.
Updated April 14 at 9:05 a.m. to include level of Lake Travis on April 14.
Although rainfall has been widespread over Central Texas from April 12-13, the Mansfield Dam floodgates onto Lake Travis are not expected to be open April 13, despite the lake’s full level status, according to the Lower Colorado River Authority.
According to LCRA's hydromet real-time gauge, the level of Lake Travis was 681.14 feet at 9:02 a.m. on April 14.
The level of Lake Travis at 4:05 p.m. on April 13 was 681.27 feet, which is slightly above its 681-foot full level, LCRA’s hydromet real-time gauge stated.
LCRA, the agency that is responsible for protecting the water quality of the Highland Lakes, will use hydro generators to maintain the lake level first before opening floodgates, LCRA Chief Meteorologist Bob Rose said. He said the hydro generators are not as hard on water channels and have electricity as a byproduct. A hydro generator uses water and fuel to make electricity.
“The last time [Lake Travis] was full was back in April of 2010,” Rose said. “It was a little over 681 [feet] at that time.
“With the rains we had last night, the level [of Lake Travis] went a little more than full—at 681-and-a-quarter—and we are trying to bring that down right now, closer to 681 [feet] at this time.”
Lake Buchanan is within 2 feet of being full, he said.
“This is a place that LCRA has not been at since about 2008—to have nearly full lakes at this time,” Rose said.
The coming weekend should bring more rain, he said.
“If the weather stays wet—which we think it will—at least for the next couple of months, the level of the lake isn’t going to change all that much,” Rose said. “We may come down into the 670s [feet] a little bit and we may lose about 3 or 4 feet by the time we get to September.”
He said “bone-dry” weather, a repeat of 2011, is not expected in the area.
In 2013 and 2014, Lake Travis levels held at 630 feet, dropping as low as 626 feet, Rose said. In the spring of last year, once El Nino really set in and Central Texas started getting significant rains in May, the level of Lake Travis started to climb before tapering off last summer, he said. The summer was a dry period in the area before Lake Travis filled up during the winter months, Rose said.