The city of Austin, Texas has approved a construction contract to build new systems to deter the invasion of Zebra Mussels at all three of its water treatment plants.
The plants will install copper ion generator systems, which will use electricity and copper electrodes to release copper ions into raw water pipelines, eliminating the need to deliver, handle, and store large amounts of copper sulfate chemicals onsite. The newly constructed systems will replace copper sulfate feed systems that are in place.
Adding copper ions to the raw water at the beginning of the process will deter zebra mussels from entering and affecting the water treatment plant infrastructure. The treatment process then removes the copper ions before the finished drinking water is sent to customers.
“The copper ion generator systems will provide a sustainable, long-term approach for fighting off the effects of this invasive species in our drinking water systems,” said Robert Goode, Interim Director, Austin Water. “This enhancement will improve the resiliency of our infrastructure, so that the treatment process continues to be reliable and effective in producing water of the highest quality for our customers.”
Zebra mussels were first detected in Lake Travis in 2017 and have since infested Lake Travis and Lake Austin, which are the source of Austin’s drinking water. Austin Water worked quickly to put chemical feed systems in place at its plants in 2019 and 2020 to deter the infestation of zebra mussels in water pipelines.
The invasive species attaches to surfaces such as grates, screens, pipes, and valves, interferes with water treatment operations, and increases the amount of energy required to pump water through the process. Their presence also can affect taste and odor of drinking water.
Construction is scheduled to begin on the copper ion generator systems in the next few months and is estimated to be completed by Winter 2023.
In addition to these systems, Austin Water also conducts routine cleaning and removal of zebra mussel shells on screens and other infrastructure; uses divers to inspect and pressure wash underwater infrastructure; and uses rovers with cameras to inspect pipelines and underwater infrastructure not readily accessible by divers. Austin Water treatment plants also have enhanced protocols to evaluate taste and odor of drinking water before it leaves the plant on a more frequent basis.
