Zebra mussels are here, everyone knows that.
While they cannot be stopped, city and state officials are looking at ways to stifle the spread of the creatures after the latest arrival in a North Texas lake.
The discovery of the destructive creatures in Lake Ray Roberts last year and the recent find in Lewisville Lake this week have city officials looking at ways of dealing with zebra mussels and the likely event of them affecting Denton’s water supply operations.
“Over a year ago, because of the discovery up in [Lake] Ray Roberts, we started to educate ourselves a little bit more on mussel management and control strategies and started to be a little more watchful in our systems and plant works,” said Tim Fisher, assistant director of water utilities for the city of Denton.
“So far we haven’t had any real infestation or operational complications, but we expect that will occur sometime in the future. You will not be able to control them in the lake. The question is can you control them in your intake? Is that control preventative or responsive and reactive?”
Fisher said he would want to take preventative measures, which can involve the use of chemical oxidants. Great care must be taken since improper dosage and management could contaminate drinking water, he said.
“What we have also seen is physical removal, taking facilities out of service and cleaning them,” he said. “That’s what we envision we will be faced [with], possibly in the next couple years.”
Originating from Eastern Europe, zebra mussels were first found in Lake St. Clair just outside Detroit in 1988. They have been found in more than 600 lakes and reservoirs in 29 states.
Zebra mussels became established in Lake Texoma in 2009 and last year were found in Lake Ray Roberts and in the Elm Fork of the Trinity River above Lewisville Lake.
Fisher said Michigan and the states that felt the early pain of zebra mussel invasion were eventually able to cope.
“But they will probably affect some systems’ operational reliability and some cost for maintenance,” he said.
The latest discovery was a small juvenile zebra mussel only 4 to 4.5 mm in size. But Brian Van Zee of the Texas Parks and Wildlife Department said it could be an indication there are larvae just now settling.
“I would imagine over time we will see the numbers increase, but right now it is early in the infestation,” he said.
Van Zee said officials are redoubling their efforts to get the word out about the preventative measures boaters can take to stop the spread of the zebra mussels in North Texas waters.
“We just need to continue trying to get the word out and stress the importance of following the simple steps of ‘clean, drain, dry,’” Van Zee said.
Taking a few minutes to check over a boat after it leaves the water could potentially help stop the spread of the mussels to other lakes, he stressed. Lewisville Lake is an extremely popular boating destination, bringing people from miles around and creating a heightened chance for the spread of the creature to other bodies of water if the preventative measures are not followed.
Van Zee admitted the level of frustration is high for officials who are dealing with the zebra mussels.
“It’s one of those things you wish you could turn back the clock and never have to deal with them. That’s the true story for any invasive species you get,” he said. “It gets to be more and more of a hassle trying to keep up with them and control them. Once they get established, there is no way to completely eradicate them. That’s where the real frustration is. You try and get the word out, but not everyone listens.”
Boaters need to listen though. There are legal ramifications if they do not.
Under the Texas Parks and Wildlife Department rules and the Texas Penal Code, possession or transporting of zebra mussels in Texas is a Class C misdemeanor punishable by a fine of up to $500 for the first offense. Repeat offenses can be elevated to a Class B misdemeanor, which is punishable by a fine of up to $2,000, jail time up to 180 days, or both. If an individual is convicted a third time for the same offense, it becomes a Class A misdemeanor, which could result in a fine of up to $4,000, jail time not to exceed one year, or both.
BJ LEWIS can be reached at 940-566-6875 and via Twitter at @BjlewisDRC.