In 1909, the South San Joaquin Irrigation District was established to provide a reliable and economical source of irrigation water for the areas around Escalon, Manteca and Ripon. SSJID's historic water rights allow for several hydroelectric power plants on a series of dams and reservoirs on the Stanislaus River. SSJID and Oakdale Irrigation District completed the original Melones Reservoir in 192
6, and have co-owned the Tri-Dam Project, consisting of Donnells, Beardsley and Tulloch reservoirs and powerhouses since 1957. In 2005, as unprecedented urban growth replaced agricultural land, the District expanded into providing domestic water service to South San Joaquin County cities with its state-of-the-art water treatment plant. In 2009, SSJID completed a 1.4 megawatt solar farm that provides nearly all of the electricity to run its water treatment plant, and the District passes on a 15% savings on power costs to the cities who participate in the treatment plant. For several years, the District has been moving towards providing retail electric service as well, aiming to cut electric bills of those in its service territory by 15% across the board.
