 Since 2003, SRGRP has delivered approximately 11 million gallons per day of tertiary treated wastewater to replenish The Geysers’ geothermal reservoir.In 2004, 85% of the effluent produced by four waste-water treatment plants serving 10 Lake County communities was diverted to the Geysers steam field.Injecting treated water into the Geysers field increases the amount of power that can be generated.