On December 13, 2001, the Regional Water Quality Control Board issued a Municipal Storm Water National Pollutant Discharge Elimination System Permit (NPDES Permit No. CAS004001) that requires new development and redevelopment projects to incorporate storm water mitigation measures, effective September 2, 2002.
Depending on the type of project, either a Standard Urban Stormwater Mitigation Plan (SUSMP) or a Site Specific Mitigation Plan is required to reduce the quantity and improve the quality of rainfall runoff that leaves the site. Developers are encouraged to begin work on complying with these regulations by visiting the Watershed Protection Division (WPD) in the design phase of their projects.
SUSMP Project Categories:roject Categories:
Site Specific Project Categories:
ÒRedevelopmentÓ means, "…any land-disturbing activity that results in the creation, addition, or replacement of 5,000 square feet or more of impervious surface area on an already developed site. Redevelopment includes, but is not limited to: the expansion of a building footprint; addition or replacement of a structure; replacement of impervious surface area when replacement is not part of a routine maintenance activity; and land-disturbing activities related to structural or impervious surfaces.
It does not include routine maintenance activities that are conducted to maintain original line and grade, hydraulic capacity, or original purpose of facility, nor does it include emergency construction activities required to immediately protect public health and safety.
Existing "non-hillside" single-family structures are exempt from the redevelopment requirements."