Lake Travis ‘infested’ with invasive, damaging zebra mussels

July 3, 2017 in News by RBN Staff

 

Source: KXAN

Zebra mussels, the invasive species that could cause major economic and environmental damage to a waterway have now been found in Lake Travis, less than two weeks after they were found in Canyon Lake.

The Texas Parks and Wildlife Department made the announcement Tuesday after a staff member at an unnamed local marina reported seeing a single zebra mussel attached to the outboard motor of a boat that was tied up on the lake on June 22. Biologists responded and found mussels attached to other boats nearby and on the marina’s submerged infrastructure.

“We just don’t want to get out of control and find out that we could have done something about it earlier and we were too slow,” said Mukhtar Farooqi, fisheries biologist for Texas Parks and Wildlife. “They will block pipes and make it very expensive for cleaning.”

Several different sizes of adult and juvenile mussels were found at two different sites on the lake, leading TPWD to declare the lake infested with a reproducing population.

This is the first time the zebra mussel has been found in any of the Highland Lakes.

Authorities said the next step after identifying an infestation is to make the public aware and educate them how to stop the spread. There is a risk of the mussels naturally dispersing downstream to Lake Austin and Lady Bird Lake, but a more immediate risk would be the mussels being transported on boats and other recreational equipment.

By law, boaters are required to drain all of the water from their boat and on-board receptacles before leaving or approaching a body of freshwater. Then, boaters must clean and dry their boats. These rules apply to all types of boats, whether they are powered or not. First incident fines can reach up to $500.

“Cleaning, draining and drying really doesn’t take much time – it’s a few simple steps that boaters can take to prevent these infestations,” TPWD’s Aquatic Invasive Species lead Monica McGarrity said. “There are more than 1,500 boat ramps in Texas and we can’t be everywhere, so we have to rely on boaters, marinas and concerned citizens to help in this fight.”

With the addition of Lake Travis, 11 lakes in four river basins are now classified as infested, meaning they have an established, reproducing population – Belton, Bridgeport, Dean Gilbert (a 45-acre Community Fishing Lake in Sherman), Eagle Mountain, Lewisville, Randell, Ray Roberts, Stillhouse Hollow, Texoma and Canyon.

Studies speculate it could cost a million dollars to retrofit a hydro-electric dam to defend against the mussels, but the LCRA isn’t worried about that — yet.

“We’d prefer not to have them but at the same time it’s not the end of the world for us in the Colorado river basin,” said John Hofmann, VP of Water for the Lower Colorado River Authority.

The intakes for the Highland Lakes’ dams will likely be spared because of the deep water. Zebra mussels can’t survive the low-oxygen levels below 25 feet. So we’ll see more damage to boats, docks, ramps and shallow water pipes. There’s no cost-effective way to kill them, so it’s up to the many boaters on Lake Travis to clear them from their boats.

“It’s literally the only way that we know we can stop them from spreading,” said Hofmann.

We also reached out to Austin Water, because their new treatment facility — water treatment plant #4 — gets your water from Lake Travis.

A spokesperson tells KXAN they have not seen any zebra mussels yet. They have filters on the intake pumps, they clean those pumps and inspect them every year. The next inspection is this fall. If they do find them, they have a mechanism that stops them from latching on to the intake pipeline.

State lawmakers provided funding to help stop the spread. In 2013, the legislature approved more than a million dollars to combat all invasive species in Texas.

Two years later, they raised that funding to more than $6 million. Texas Parks and Wildlife launched an awareness campaign, including pamphlets like this to give boaters tips on ways to stop the spread.

The campaign pounds three points home: Clean, Drain and Dry. Boaters are supposed to clean their boats after leaving a lake. They also have to drain out all the water and dry the boat off before heading out to another lake. It’s not just a suggestion, it’s the law.

Current Texas zebra mussel map (TPWD photo)
Current Texas zebra mussel map (TPWD photo)