Nontoxic Sparker Control of Zebra Mussels

Following their inadvertent introduction to Lake St. Clair, zebra mussels quickly spread throughout the Great Lakes and into many inland lakes, rivers, and canals. Zebra mussels clog intake screens, pipes, and cooling systems and pose a serious problem. Chlorine injection effectively controls zebra mussels, but also produces toxic byproducts, some of which are carcinogenic. Furthermore, regulatory actions in the United States and Canada are expected to eliminate chlorine for controlling zebra mussels. The objective of this project is to demonstrate the feasibility of using high-intensity pressure pulses from sparkers for the nontoxic, low-cost control of zebra mussels. Sparker pressure pulses both prevent young zebra mussels from attaching to surfaces and eradicate attached mature zebra mussels by interfering with feeding. Acceptance of the only commercial sparker for controlling zebra mussels has been limited in part because it requires maintenance twice per day. In addition, potential users are unconvinced that the sparker will work at their sites because the pressure levels needed to control zebra mussels are not known. In Phase I, Phoenix Science & Technology, Inc., will implement an "innovative" electrode to increase the maintenance time from twice per day to once every 5 weeks. The new electrode will be tested at a commercial water plant, and pressure levels that both prevent and eradicate zebra mussels will be measured. These pressure measurements will be used to begin development of a phenomenological design model for zebra mussel control to support widespread use of sparkers.