La Mesa, CA Water Use Rules: Recycled Water Rules (2026)

LMMC § 14.29.160, part of the Water Efficient Landscape Regulations, imposes a mandatory-use rule rather than an option: any person who obtains a permit for a project covered by Chapter 14.29 must use recycled water for irrigation once tertiary treated recycled water is available from the purveyor supplying the property. Compliance requires installing a dual distribution system separate from the potable water received from the public purveyor, and every pipe carrying recycled water must be colored purple, the industry-standard warning color the section writes directly into the code.

In exchange, a permit holder who irrigates with recycled water is entitled to an ET adjustment factor (ETAF) of 1.0 when calculating the maximum applied water allowance under § 14.29.110, a more generous water budget than the 0.7 ETAF used for potable irrigation. The section closes by making clear that using recycled water does not excuse compliance with any other state or local recycled-water law. The rule attaches to the same permit-triggered projects as the rest of Chapter 14.29: commercial, industrial, institutional or multi-family projects with 2,500 square feet or more of landscaped area, and new single-family homes with 5,000 square feet or more of homeowner-provided landscaping, per § 14.29.030, with the community development director administering enforcement under § 14.29.040.