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New Calif. "Model Water Efficient Landscape Ordinance"07-23-15 | News

New Calif. "Model Water Efficient Landscape Ordinance"

California Gov. Jerry Brown's April 1, 2015 executive order on the drought required the California Department of Water Resources to update its Model Water Efficient Landscape Ordinance. The public draft https://tinyurl.com/o37kn9b of the update was released June 12, 2015. For new or redeveloped landscapes turf is not to exceed 25% of the landscape area in residential areas, and no turf is allowed in nonresidential areas.
Image: CDOWR

After Calif. Gov. Jerry Brown announced mandatory water cutbacks on April 1, the Calif. Water Commission was tasked to further tighten the state's water restrictions. The new rules apply to newly built landscape areas greater that 500 square feet or remodeled landscapes larger than 2,500 sq. ft. (i.e., projects that require a building or landscape permit, plan check or design review.

Turf is not to exceed 25% of the landscape area in residential areas, and no turf is allowed in nonresidential areas.

Turf can't be be planted on sloped areas that exceed 1" vertical elevation change for every 4' of horizontal length.

Turf is prohibited in parkways less than 10 feet wide, unless the parkway is adjacent to a parking strip and used to enter and exit vehicles. Any turf in parkways must be irrigated by subsurface irrigation or by other technology that creates no overspray or runoff.

Automatic irrigation controllers are required, and must use vapotranspiration or soil moisture sensor data.

All planted landscape areas are required to have friable (crumbly texture) soil to maximize water retention and infiltration.

It is strongly recommended that landscape areas be designed for capture and infiltration capacity that is sufficient to prevent runoff from impervious surfaces (i.e., roof and paved areas) from either a 1" 24-hour rain event, or the 85th percentile, 24-hour rain event, and/or additional capacity as required by any applicable local, regional, state or federal regulation.

It is recommended that stormwater projects incorporate any of the following elements to improve on site stormwater and dry weather runoff capture and use:
-Grade impervious surfaces, such as driveways, during construction to drain to vegetated areas.
-Minimize the area of impervious surfaces such as paved areas, roof and concrete driveways.
-Incorporate pervious or porous surfaces (gravel, permeable pavers or blocks, pervious or porous concrete) that minimize runoff.
-Direct runoff from paved surfaces and roof areas into planting beds or landscaped areas to maximize site water capture and reuse.
-Incorporate rain gardens, cisterns and other rain harvesting or catchment systems.
-Incorporate infiltration beds, swales, basins and dry wells to capture stormwater and dry weather runoff and increase percolation into the soil.
-Consider constructed wetlands and ponds that retain water, equalize excess flow, and filter pollutants.

The final Model Water Efficient Landscape Ordinance will be released after the California Department of Water Resources reviews all public comments.

The ordinance does not apply to:
(1) Registered local, state or federal historical sites.
(2) Ecological restoration projects that do not require a permanent irrigation system.
(3) Mined land reclamation projects that do not require a permanent irrigation system.
(4) Existing plant collections, as part of botanical gardens and arboretums open to the public.