By 1999 the steam to power extraction had begun to deplete the Geysers steam field and production began to drop.[2] However, since October 16, 1997, the Geysers steam field has been recharged by injection of treated sewage effluent, producing approximately 77 megawatts of capacity in 2004.[11] The effluent is piped up to 50 miles (80 km) from its source at the Lake County Sanitation waste water treatment plants and added to the Geysers steam field via geothermal injection.[11] 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.[11] Injecting treated water into the Geysers field increases the amount of power that can be generated