Dear Brushy Creek residents,
We want to update you on a project that we completed two years ago. In fall 2022, the District installed a copper ion generation system at its water intake facility at Lake Georgetown. The goal was to diminish the number of zebra mussels in our water system since they started infesting the lake around 2017.
As of now, all of our facilities, from the lake intake to the infrastructure at our Water Treatment Facility, are 100% free of zebra mussels.
We are happy to bring you, our valued residents, this news. It is truly a measure of how we consistently strive to maintain The Brushy Creek Life.
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BRUSHY CREEK MUNICIPAL UTILITY DISTRICT, Dec. 12, 2024
Despite their growing numbers in water sources throughout Texas, zebra mussels are not something Brushy Creek MUD Facilities Manager Bill Carr worries about anymore.
That is due to a major capital improvement project that District leaders brought to fruition from mid-2021 to late fall 2022. Now complete and running smoothly for the last two years, BCMUD’s Copper Ion generation system allows Carr and his crew to breathe easy, at least when it comes to zebra mussels, he said.
Prior to the copper ion system, BCMUD water operators were engaged in what Carr now describes as unsuccessful measures to defeat the invasive and harmful aquatic species.
“Zebra mussels were first noticed at Lake Georgetown in 2017,” Carr said. “Around 2018 we started feeding sodium permanganate at the [BCMUD] Water Treatment Facility. The hope was to keep the mussels out of our raw water pond and all of the piping infrastructure at our facility.”
That method proved less effective than Carr would have liked, and for the next two years, he and his team tried several other chemical-based methods, but he said none were as effective as the copper ion system has proven to be.
In a recent report from the Brazos River Authority, Brad Brunett, BRA central and lower basin regional manager, said copper ion generator systems work by allowing low doses of copper solution where districts and entities like BCMUD draw water from sources such as Lake Georgetown.
“The increased copper concentration will hinder zebra mussel development … providing a chemical-free means of tackling the invasive, fingernail-sized mollusks that can negatively impact water supply infrastructure,” Brunett said in the article.
Carr said that although the price tag for the copper ion system came in at $783,000, the long-term savings for BCMUD have offset the initial cost several fold.
“The first set of copper rods used in the copper ion system lasted us almost 18 months at a cost of about $4,500 a piece,” he said. “Previously, we were spending $4,500 every two months on chemicals. In the long term, the cost savings are enormous.”
But even if the money saved was minimal, Carr said the copper ion system installation would be justified.
Information from the Texas Parks and Wildlife Department states that since they were first found in Lake Texoma in 2009, zebra mussels have fully infested 33 Texas lakes as of summer 2024, including Lake Georgetown and Stillhouse Hollow Lake, BCMUD’s two largest water sources.
Texasinvasives.org highlights the devastating impact of zebra mussels on Texas’ natural resources. These invasive species can clog water intake systems, disrupt ecosystems, and contaminate water, resulting in foul-smelling water for thousands of homes at a time. Additionally, they impose significant costs on utilities and subsequently on taxpayers that can amount to millions of dollars.
In February 2019, zebra mussels overwhelmed the intake at the Ullrich treatment plant that draws water from Lake Austin. The resulting foul-smelling water seeped into the taps of thousands of homes in Central and South Austin neighborhoods.
Austin Water reported at that time the city of Austin used chemical retardants to combat zebra mussels. Once the infestation took hold, one of the raw water tunnels at the Ullrich treatment plant had to be temporarily shut down while the issue was fixed. Since then, the City of Austin has worked to install copper ion systems in three of its major intakes.
Julie Hollandsworth, Austin Water operations and maintenance division manager, said the city of Austin still plans to install copper ion systems in three of their intakes, but there have been hurdles largely due to the size of the city’s water operation, as well as equipment delays from the manufacturer. She added the city could have its copper ion systems running sometime in the coming calendar year.
“We’ve seen good results from the copper sulfate [we’re using now],” Hollandsworth said. “We have no reason to think the copper ion system will work less well.”
In addition to its effectiveness over more common methods of zebra mussel abatement, the copper ion system is also more environmentally friendly, Carr said. Because it carries virtually no likelihood of a chemical spill like the sodium permanganate system, the risk of water source pollution is basically nonexistent.
Through the copper ion system, Carr said they’re able to render the zebra mussels harmless at a dose of under 10 µg/L, or parts per billion (ppb), of copper, and explained the Environmental Protection Agency (EPA) has set the maximum contaminant level (MCL) in drinking water for copper at 1,300 ppb.
For added safety, Carr said BCMUD regularly tests the water at its treatment plant.
“On average, our finished water going out to customers tests at about 3 ppb of copper, which is substantially below the allowable limit,” he said.
Since BCMUD completed the copper ion system installation at its intake facility on the banks of Lake Georgetown in 2022, Carr said there is now enough proof of its effectiveness to warrant peace of mind. The numbers do, in fact, speak for themselves, he said.
“BCMUD now has two years of data showing that we do not have zebra mussels in our system,” he said. “Before that, when we were implementing the sodium permanganate system, when we’d drain our pond to clean it, it was completely infested with zebra mussels.”
Carr explained that prior to the copper ion system the infestation was so ubiquitous that no metal was visible on the screens between BCMUD’s raw water pond and its water treatment plant, and the walls of the raw water station that pumps water into the District’s Water Treatment Facility were completely covered with zebra mussels.
“Now, we have none,” he said.
To be clear, BCMUD's copper ion system has not eliminated zebra mussels from Lake Georgetown, and Carr said the aquatic species can cause major problems in water systems, but this technology has safely and effectively eliminated the risk for BCMUD facilities.
After a recent trip to Lake Georgetown in November 2024 to check on the intake facility, Carr also examined the copper ion system components. Inside a small building, the copper ion system displays a touchscreen control panel in addition to an intricate network of filters, ion chambers, pressure gauges, and control valves. Carr confirmed the system is still operating perfectly for BCMUD.
“We were one of the first water entities in Central Texas to have this system, so we did have a few kinks to work out at start-up, like figuring out flow and air relief issues,” Carr said. “But now, I’m a firm believer in copper ion because long-term, it’s just a really good system. Additionally, it represents our ongoing efforts in this District to embody the Brushy Creek Life.”