San Dieguito Water District in Encinitas, formed in 1922 under the California Irrigation District Act, is a public agency providing potable and recycled water service to Old Encinitas, Leucadia, Cardiff-by-the-Sea, and portions of New Encinitas. A subsidiary of the City of Encinitas since the 1986 municipal incorporation, the district coordinates infrastructure maintenance and capital improvement projects through the City of Encinitas Public Works department at the municipal complex. The district purchases wholesale supply through the San Diego County Water Authority and supplements it with local sources and recycled water for irrigation, maintaining APWA accreditation for its operational standards. Water-quality monitoring and habitat-impact assessments for the district's coastal delivery network intersect with the conservation management of San Elijo Lagoon and Ecological Reserve, where stormwater runoff and reclaimed-water discharge require coordinated oversight. The district shares the R.E. Badger Water Filtration Plant and San Dieguito Reservoir with Santa Fe Irrigation District, a joint-facility arrangement that processes imported and local raw water through flocculation, sedimentation, and granular-media filtration before distribution across the coastal service territory.