The District utilizes approximately 140 miles of sewer pipeline to collect between 400-500 million gallons of sewage per year. The Sonora Regional Wastewater Treatment Plant was constructed in the late 1970’s along with a network of sewer trunk lines to collect sewage from the surrounding areas of Columbia, East Sonora, Mono Village, Mono Vista, Ranchos Poquitos, Soulsbyville, Twain Harte, and Willow Springs. Also in the late 1970’s, a regional reclamation system was constructed that allows for the reuse of the treated sewer effluent for irrigation on pasture lands outside of the community of Jamestown. The overall sewer system directly serves approximately 6,000 residential, commercial and industrial customers.