California Code of Regulations › Title 23 - Waters › Division 2 - Department of Water Resources › Chapter 2.7 - Model Water Efficient Landscape Ordinance › Section 492.16 - Stormwater Management and Rainwater Retention

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a)
				Stormwater management practices minimize runoff and increase infiltration which
				recharges groundwater and improves water quality. Implementing stormwater best
				management practices into the landscape and grading design plans to minimize
				runoff and to increase on-site rainwater retention and infiltration are
				encouraged.
(b) Project applicants
				shall refer to the local agency or Regional Water Quality Control Board for
				information on any applicable stormwater technical requirements.
(c) All planted landscape areas are required
				to have friable soil to maximize water retention and infiltration. Refer to
				§
									492.6(a)(3).
(d) 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: the one inch, 24-hour rain event or (2) the 85th percentile, 24-hour
				rain event, and/or additional capacity as required by any applicable local,
				regional, state or federal regulation.
(e) It is recommended that storm water
				projects incorporate any of the following elements to improve on-site storm
				water 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 (e.g., 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 drywells
				  to capture storm water and dry weather runoff and increase percolation into the
				  soil.
* Consider constructed wetlands and ponds that retain water,
				  equalize excess flow, and filter pollutants.
1. New section
				  filed 9-10-2009; operative 9-10-2009 pursuant to Government Code section
				  11343.4
				  (Register 2009, No. 37).
2. Renumbering of former section
				  492.16 to section
				  492.17 and renumbering of former
				  section 492.15 to new section
				  492.16, including amendment of
				  section heading, section and NOTE, filed 9-15-2015; operative 9-15-2015. Exempt
				  from OAL review and submitted to OAL for printing only pursuant to Governor's
				  Executive Order No. B-29-15 (4-1-2015) (Register 2015, No. 38).
Note: Authority cited: Section
					 65595,
					 Government Code; and sections
					 11 and
					 30, Governor's Exec. Order No.
					 B-29-15 (April 1, 2015). Reference: Section
					 65596,
					 Government Code; and section
					 11, Governor's Exec. Order No.
					 B-29-15 (April 1, 2015).