Once zebra mussels or quagga mussels are widely distributed throughout a large lake, there is little hope for eradication with currently available methods. In these cases, it is important to let go of the myth that invasive mussels must be eradicated. This myth feeds a common, but mistaken, perception that control measures are costly and futile once invasive mussels are firmly established.
Good engineering is absolutely vital for the smooth operation of any water treatment plant or power generation facility, but time and zebra mussels wait for no one — not even engineers. Developing and installing new technologies takes time — sometimes years. Without immediate control measures in place, zebra mussels have that much more time to wreak havoc.
Copper is toxic to fish at high concentrations. That much is true. But copper is also a natural element that is approved for use in drinking water. When used efficiently, at concentrations well below the minimum for drinking water, it is not a threat to fish or to the larger ecosystem.