Irvine, CA Water Use Rules: Recycled Water Rules (2026)

Irvine's Hillside Overlay District regulates development in the San Joaquin Hills and Lomas de Santiago Hills through a review procedure in Zoning Ordinance Section 5-4-3, and Section 5-4-4 layers on additional slope-analysis, grading, and landscaping standards for projects within those specific hillside areas shown on Figures 5-4B and 5-4C. Within the landscaping subsection, Section 5-4-4.D.1 states that, where feasible, all landscaped common areas shall use recycled water when permanent irrigation is required and the supply of recycled water is adequate. The standard is conditional rather than an absolute mandate, it applies only where a recycled-water connection is feasible and the local supply can support it, but it is paired with mandatory revegetation of all cut and fill slopes and a required landscape and irrigation plan submittal for City approval under Section 5-4-4.D.2.

The same feasibility-based recycled-water directive recurs elsewhere in Irvine's planning-area-specific development standards. In Planning Area 22, for example, Section 9-22-5 similarly requires landscaped common areas to use reclaimed water for permanent irrigation where feasible, meaning where reclaimed water line hookups are available, and the supply is adequate, showing the City applies the same conditional recycled-water expectation across separate master-planned areas rather than as a single citywide mandate. Applicants seeking approval for a hillside or planning-area project should coordinate with Irvine Ranch Water District early in design to confirm recycled-water line availability, since the feasibility determination, not a hard citywide requirement, drives whether potable irrigation can be used instead.