Reduced river flow in Llano putting pressure on Highland Lakes
The city of Llano began installing wooden boards on the Llano River Dam on June 18 in accordance with the city’s drought contingency plan. Extreme drought conditions have dropped the flow rate of the Llano River to less than 1 cubic-foot per second.
The reduced flow of the river affects more than the city of Llano. Downstream communities in the Highland Lakes are also feeling the drain. The Llano River merges with the Colorado River in Kingsland, feeding into lakes LBJ, Marble Falls, and Travis.
The Colorado River flows into the Highland Lakes from Lake Buchanan, which is also suffering from extreme drought. Lake Buchanan was 98.6 percent full on June 22, 2021. As of Wednesday, June 22, 2022, it was 78.6 percent full, according to the Texas Water Development Board.
According to the National Integrated Drought Information System, 2022 is the driest year on record for Llano County and Burnet County. Both counties are down more than 7 inches of rainfall from normal.
The wooden panels are being installed along the length of the dam to raise its overall height, allowing for more water to be captured. The measure was approved by the Llano City Council in a special meeting on June 14.
According to Llano’s drought contingency plan, the wooden structure is to be put in place if the flow rate of the Llano River drops below 80 cubic-feet per second after March 1. By March 11, 2022, the river’s flow rate was consistently less than 80 cubic-feet per second, according to the U.S. Geological Survey.
The boards were not installed sooner because they were either lost or destroyed in the historic flooding of 2018, Llano City Manager Erica Berry said. New ones had to be built.
Llano is permitted to hold 700 acre-feet of water behind the dam by the Texas Commission on Environmental Quality. Installing the boards will help reach that number, Berry continued.
City workers are using a barge to install the barrier. The project is expected to be completed within a week.