AUSTIN (KXAN) — Divers discovered invasive zebra mussels covering screens on city of Austin water intake valves, signaling that in addition to the host of concerns for boaters, property owners, and native species, the zebra mussels will mean extra work the city’s water supply.
The divers confirmed the presence of this invasive species on water intake valves on September 7 during a report they were helping Austin water with. The mussels were found at the Handcox Water treatment plant valves at Lake Travis.
Specifically, there are three water intake structures at Handcox, the top intake valve had about half of its screen covered with zebra mussels, and the middle intake valve 50 feet below the screen was 20 to 30 percent covered.
Divers are slated to inspect Austin’s other two water treatment plants: Ullrich and Davis which are on Lake Austin. Morabbi said equipment at those plants has been found to have zebra mussels, so the city expects to find more zebra mussels at the intake valves there as well.
Mehrdad Morabbi, the operations manager for water treatment with the city of Austin, said the city was expecting this to happen eventually and had been talking with local agencies about how to prepare.
“In this case, we’re really looking at restriction to our pipes and damage to our equipment, so things that are costly to repair if we’re not staying ahead of this,” Morabbi said.
He added that the mussels may ultimately impact water quality or add unpleasant odors or tastes to the water, but he believes the city has the chemicals to deal with those outcomes if they unfold.
“I think its’ something we can absorb in our budget within water treatment, so no I don’t expect to have a rate increase associated with that,” he said.
Morabbi explained that the zebra mussels are likely here to stay, so the city has to figure out how to cope with them without impacting water quality or incurring a big expense.
Already, the city has increased preventative maintenance on their equipment, they’ve increased their contract with the divers and they’ve expanded zebra mussel cleaning.
Currently, the city has budgeted $212,000 per year to cover the diving teams and will likely take on other expenses because of the mussels, though it’s tough to know how much.
The city will also have to pay for a consulting firm who will look at options to cut down on the zebra mussels and will likely need to pay for some chemicals to help in treating the water.
But Morabbi noted, “there’s at a certain point we just can’t go beyond because we can’t inject chemicals into the lake.”
He added that is why the divers will need to clean most of the zebra mussels off by hand.
The city has completed an engineering report regarding the zebra mussels and hopes to start putting some of those solutions to work within the next three to six months.
Brent Lyles, the executive director of the Colorado River Alliance, explained that these mussels not only pose threats for the city of Austin’s water, but also for the other species that rely on the river.
“The Colorado River is our community’s lifeblood in so many ways, and when that ecosystem changes, that impacts the long-term health of that river,” Lyles said. “And it’s heartbreaking as someone who watches out for our river.”
He explained that it will be important for the public to be careful to dry off boats and equipment after entering the water to avoid spreading these zebra mussels even further downstream.
“There have been some cases in other areas where algae blooms have occurred after a zebra mussel infestation, we have not seen that here yet, but we’re keeping an eye out for it,” Lyles said. “And that’s a big deal if it happens.”
Zebra mussels were first found in Texas in 2009. They were first sighted in the Austin area in 2017, starting off in Lake Travis and then spreading from there. According to Texas Parks and Wildlife, the infested lakes include Lake Austin, Canyon Lake, Lake Georgetown, and Lake Travis. Both Lady Bird Lake and the Colorado River downstream of Austin have been found to have zebra mussels, but they have not yet been declared infested.
According to the city of Austin’s watershed protection department, Austin’s local creeks and Barton Springs Pool are now at risk. If Barton Springs becomes infested, the city will incur a regular cost to keep cleaning it.
The city recommends that any time you get into a body of water you:
- Wash your swimsuit, water shoes, wetsuits, and towels in hot water and dry them thoroughly
- Clean and dry all toys, coolers, rafts, buckets, and other items
- Clean and dry your dog(s)
Texas Parks and Wildlife has been calling on people who get in the water statewide to clean, drain, and dry their boats and equipment after each trip to a waterway to stop the spread of zebra mussels.
In Texas, possession or transportation fo zebra mussels is a Class C misdemeanor for a first offense, punishable with a fine of up to $500. Repeat offenders can wind up with a fine of up to $2,000, jail time up to 180 days, or both.