Reduced Pressure

Reduced pressure is a viable means of establishing zebra mussel mortality in pipes where the flow consists of raw untreated water. Vacuum pressure of 14-15 psi will reduce the dissolved oxygen in the water to near zero, thereby suffocating the mussels. The procedure may be successful in air or under water (Lei 1992), as long as the pressure is maintained at 14-15 psi.

The procedure as described by Miller et al. (1992) is as follows:

• After the zebra mussel-infested pipes have been partially drained and tightly sealed, they must then be subjected to continuous vacuum pressure of 15 psi for 2 to 3 days to achieve the goal of 100-percent zebra mussel mortality.

• At the end of the 3 day period, the pipe should be backflushed to thoroughly remove the dead mussels.

It is suggested (Miller et al. 1992) that long lengths of pipe be subdivided into sections to increase the effectiveness of this procedure.

Management and Control Contents

Management and Control Options

Prospective Control Methods