Austin-area lake is now ‘fully infested’ with zebra mussels

Lake Walter E. Long is fully infested with invasive species, TPWD officials say

Walter E. Long Lake in east Austin, Texas. (Cesar Garza, Flickr)

AUSTIN, Texas – Another Texas lake is now considered “fully infested” with zebra mussels.

Lake Walter E. Long in Travis County already had a positive designation for the invasive species, but now zebra mussels have been fully established and are reproducing in the lake, according to a news release from the Texas Parks and Wildlife Department.

“Unfortunately, zebra mussels have now spread to 34 Texas lakes, with 30 now fully infested, but there are far more lakes in Texas that still haven’t been invaded and are at risk,” said Brian Van Zee, TPWD Inland Fisheries Regional Director. “Each boater taking steps to clean and drain their boat before leaving the lake and allowing compartments and gear to dry completely when they get home can make a big difference in protecting our Texas lakes.”

Zebra mussels were first noted in the lake in October 2018 and were found again in May 2019.

Subsequent searches for settled mussels conducted as recently as 2021 did not detect any juveniles or adults, according to TPWD officials.

City of Austin Watershed Protection biologists conducted shoreline searches for zebra mussels and found two adults in the lake in early August, indicating the presence of an established population.

Since Diversion Lake is immediately downstream of fully infested Medina Lake, downstream dispersal likely led to the infestation, officials said.

According to TPWD officials, zebra mussels arrived in North America sometime in the late 1980s and spread like wildfire via the Mississippi River and have traveled overland on boats as far as California.

Boaters are asked to remove all plants, mud and debris from boats, trailers, vehicles and gear and drain all water from the boat, equipment and onboard receptacles before leaving lakes.

TPWD recommends letting a boat dry for at least one week before visiting a different lake. If drying isn’t possible, TPWD recommends washing the boat with high-pressure water from a carwash or spray nozzle on a water hose before visiting another lake to help reduce the risk of spreading aquatic invasive species.

Anyone who sees an invasive species in a lake where it hasn’t previously been reported is asked to call TPWD at 512-389-4848 or send an email, with photos if you have them, and specific location information to

Lake Walter E. Long is located in Austin. Access to the lake can be found at 6614 Blue Bluff Road in the Walter E. Long Metropolitan Park.


About the Author:

Mary Claire Patton has been a journalist with KSAT 12 since 2015. She has reported on several high-profile stories during her career at KSAT and specializes in trending news and things to do around Texas and San Antonio.