Bubble Wall Could Stop Spread of Aquatic Invasive Plants in Lake Tahoe
Crews installed a bubble wall between the Tahoe Keys and Lake Tahoe, hoping it will prevent the spread of aquatic invasive plants while they search for a long-term solution.
Residents of Lake Tahoe continue to fight the spread of aquatic invasive plants. The League to Save Lake Tahoe is partnering with the Tahoe Keys Property Owners Association, using old technology for a new purpose in the Tahoe Keys Marina.
Bubble curtains are used all over the world to prevent debris from floating into a specific area. Now they are being used to prevent plant fragments from spreading from the Keys to the lake.
"Once they get a hold of Lake Tahoe, they change the whole ecology of the lake, provide habitat for other invasive species and actually make nutrients more available for algae which none of us want to see on our rocks here in Lake Tahoe," Jesse Patterson, Deputy Director of the League to Save Lake Tahoe said.
The League to Save Lake Tahoe is partnering with the Tahoe Keys Property Owners Association. They installed an air compressor on May 10, which sends air into perforated hoses. Those are positioned in a V shape and spread across the floor of the channel that connects the Keys to the lake. It creates a wall of bubbles that could block the plants and funnel them to the edges.
"A lot of the boats will sit in the water and their props will get infested with weeds and wrapped around it as they go through the lagoons," Greg Hoover, Tahoe Keys Water Quality Manager said.
"This bubble curtain just stops them," Patterson said. "It allows the boats through but stops the fragments."
The Tahoe Keys cover 172 acres and Patterson says about 90 percent of them are infested with invasive weeds, particularly curlyleaf pondweed and Eurasian watermilfoil. Preventing them from spreading could buy some time while officials find a permanent solution to get rid of the plants.
"It's really about stopping the spread so we can figure out a long-term solution in the Keys, which will be far more expensive and complicated but we don't want to put the lake at risk while we're trying to figure that out," Patterson said.
Patterson hopes to see results in about a month. If it is successful, the same technology could be used in other infested marinas. Aquatic invasive plants are confirmed in 18 locations around Lake Tahoe. Bottom barriers are used in small areas to eliminate the weeds. They are basically tarps that are spread over the plants to prevent photosynthesis. Those usually work better in small areas and Patterson says it could take a combination of strategies to kill the plants.
"We need more tools in the toolbox and the bubble curtain gives us the time to find those tools," Patterson said.
The Tahoe Keys Property Owners Association has spent $2.1 million over the past few years to control the project and a lot more money will likely be needed to solve the problem.
Along with the bubble wall, boat operators are encouraged to use the boat backup stations.
"The boats come through, they stop, reverse their propeller and then they back up, which clears the propeller of all the weeds so that it doesn't drag out into the lake," Hoover said.
Hoover says there is a 66 percent compliance rate from boat operators who use the backup stations. He hopes that increases to decrease the chances of spreading the plants. Patterson says solving the problem of aquatic invasive species will likely take several years.