Vacaville, CA Landscaping Rules: Rainwater Harvesting (2026)

27's landscape design standards for new construction and rehabilitated landscapes. Subsection A frames storm water best management practices, including on-site rainwater retention and infiltration, as 'encouraged' rather than required. Subsection D sets the one firm numeric standard: landscape areas must be designed with capture and infiltration capacity sufficient to prevent runoff from impervious surfaces, roofs and paved areas, from either the one-inch, 24-hour rain event or the eighty-fifth percentile, 24-hour rain event, plus any added capacity required by other local, regional, state, or federal rules.

Subsection E then lists specific rainwater techniques a storm water project must incorporate at least one of, item 5 naming 'rain gardens, cisterns, and other rain harvesting or catchment systems' alongside grading impervious surfaces to drain toward vegetation, minimizing paved area, using pervious surfaces, directing roof runoff into planted beds, and building infiltration beds, swales, basins or drywells. 3, meaning compacted soils must be loosened before planting to maximize infiltration. Subsection B directs applicants to the local agency or the Regional Water Quality Control Board for any additional applicable storm water technical requirements beyond this chapter.