MARBLE FALLS — Invasive water weeds, including hydrilla and milfoil, have clogged municipal water-intake systems this summer and caused concerns about swimming and recreational activities on the Highland Lakes, officials say.
“It’s largely in Lake Marble Falls, but it’s affecting LBJ as well,” Burnet County Precinct 4 Commissioner Joe Don Dockery said. “It’s not only affecting us from a recreation standpoint, it’s starting to affect municipalities from their water-intake standpoint.”
Hydrilla and milfoil, vegetation that takes root in shallow areas of waterways, thrives primarily in coves and around docks, parks and boat ramps.
Residents might have noticed thick mats, tangled clumps and strands of the weeds in various parts of the lakes.
“If you’ll go down to some of the park areas that have shallow water such as Pecan Valley Property Owners’ Association Park, Meadowlakes POA park, you’ll see that people aren’t swimming,” Dockery said. “The reason they’re not swimming is because these plants, you can become entangled in them. It can be a safety hazard where, if you’re a young child and you got entangled in them, it could lead to drowning.”
Marble Falls city officials say the vegetation has damaged water-plant equipment in the past several weeks.
“We burned out a couple of motors. They clogged up the intake, and the motors overheated and burned out,” Mayor George Russell said. “There’s more than one intake, so you flip over to the alternative.”
The city of Granite Shoals reported clogged intake issues caused by the invasive weeds this summer as well as the summer of 2013, city officials said.
As a result of the issues, Russell, Dockery and officials with the Texas Parks and Wildlife Department and the Lower Colorado River Authority have recently met to discuss ways to tackle the issue without threatening resources.
“Here we are trying to protect our water source, and the last thing we want to do is to pour chemicals into the water that are not approved appropriate for that use,” Dockery said.
Short-term solutions include state-approved treatment with copper-based herbicides to kill the weed. Property owners must apply for permits to do so, and such abatement might not treat limited areas.
“We’re trying to get some sort of larger permit for the city and the county to do something about it,” Russell said.
Texas Parks and Wildlife crews have utilized the herbicides in Lake Marble Falls at least three times this summer through July 31, Russell said.
“It’s a copper-based product. The liquid one does not affect drinking water,” Russell said. “It is killing it and wilting a weed. It deteriorates on the bottom.”
Other solutions include asking boaters to clear their vessels, equipment and gear of the weeds. Proper disposal involves drying out the weed on a non-vegetative surface.
“In my view, this can almost be as detrimental as the zebra mussels have been in their influx into the Texas waterways,” Dockery said. “We want to make sure we’re not just protecting the recreational aspect of the lake, but we got to make sure we’re ensuring our potable water source.”
By the fall, the problems with the weed should subside as the plants become dormant and a food source for water fowl.
In the meantime, boaters, swimmers and others taking part in lake recreation can attempt to steer clear of the pesky plants.
“The concern right now is for LakeFest this weekend to make sure the boaters involved are safe on the water,” Russell said. “We’re trying to put together a plan of action so that we can be aggressive on this next year.”
To apply for permit for either manual removal or to utilize a herbicide program, visit the LCRA website at www.lcra.org or the Texas Parks and Wildlife Department at www.tpwd.state.tx.us for more information.