Study to quantify benefits of replacing turf being expanded following first phase

SCCWRP and the County of San Diego are moving to the next phase of a study seeking to quantify the runoff water quality benefits of replacing residential grass with drought-tolerant landscaping, following the successful completion of the study’s initial phase.

The study, which the County extended and expanded in October, represents a first-of-its-kind effort to quantify how much runoff can be eliminated by replacing turf and traditional spray irrigation with drought-tolerant landscaping and drip irrigation. The study’s first phase – in a residential community in Spring Valley – demonstrated that it is possible to measure reductions in the volumes of runoff from irrigation following turf replacement.

During the next phase, researchers will continue measuring dry-weather irrigation runoff volumes, as well as examine whether turf replacement also can reduce volumes of wet-weather runoff by absorbing more rainfall on site.

Water districts commonly offer property owners rebates and incentives for turf replacements. By assessing the potential of turf replacements to improve runoff water quality, the County of San Diego study will help stormwater management agencies decide whether they also should expand their turf replacement investments.