A fish kill occurred on the Brazos River downstream of the DeCordova Bend Dam at Lake Granbury, Monday, July 22. The die-off of hundreds of fish occurred following the closing of floodgates at Lake Granbury after more than three months of water releases brought about by heavy spring rains.
“There has been a great deal of concern regarding the recent fish kill below Lake Granbury,” said Judi Pierce, public information officer for the Brazos River Authority. “We’ve had a number of people express concern about the health of the Brazos River and its potential effect on humans and wildlife.”
According to the BRAs Environmental and Compliance Manager, Tiffany Morgan, the recent fish kill occurred due to a lack of dissolved oxygen in the stilling basin just below the dam, not due to toxins in the river.
Reservoir Manager Connie Tucker stated that during the months of floodwater releases, fish gathered in the dam structures stilling basin. As temperatures rose, the decrease of dissolved oxygen in the water resulted in the large number of fish becoming distressed or dying. Floodgates were temporarily reopened to increase the oxygen levels in the water below the dam, sending both dead and dying fish downstream.
Though toxins in the water were not responsible for the fish deaths, during past fish kill events, the Texas Parks and Wildlife Department, the Texas Commission on Environmental Quality and the US Fish and Wildlife Service all stated that swimming near dead fish is not recommended as bacteria levels associated with decomposition may be high. Fishing in the Brazos River and consuming fish caught below Lake Granbury continues to be safe; however, dead or dying fish should not be eaten.
Additional fish continue to congregate in the deeper water just downstream of the DeCordova Bend Dam. With end-of-summer temperatures continuing to soar and a decline in reservoir releases expected as dry conditions continue into the fall months, additional fish kills are possible.
For questions on the fish kill, contact the BRA Public Information Office at 888-922-6272.