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Storm Water Program


  1. What state storm water requirements apply to school projects?
    School construction activity resulting in a land disturbance of one acre or more, or less than one acre but part of a larger common plan of development or sale must obtain coverage under the Construction Activities Storm Water General Permit (General Permit).  Construction activity includes clearing, grading, excavation, stockpiling, and reconstruction of existing facilities involving removal and replacement.   General Permit coverage is obtained through the State Water Board.  General Permit requirements are enforced by the Regional Water Quality Control Board where the project is located.

    Schools may also be subject to post-construction storm water requirements.  Municipal storm water permits contain specific requirements for post-construction storm water quantity controls (e.g., maximum amount of allowable impervious surface, runoff detention/retention basins) and quality controls (e.g., infiltration trenches, grass swales/channels).  Attachment 4 of the Small Municipal Separate Storm Sewer System (MS4) Phase II Permit contains the general requirements.  The applicant is encouraged to contact the appropriate Regional Water Quality Control Board Staff for specific post-construction storm water requirements.

    Storm water discharges in the Lake Tahoe Hydrologic Unit are regulated by a separate construction permit(s) adopted by the respective Regional Water Quality Control Board, and may not seek coverage under the State Water Resources Control Board's General Permit.

  2. If I am implementing a Construction Site Storm Water Runoff Control Program in compliance with the Small MS4 Phase II Permit, do I need coverage under the General Permit for Discharges of Storm Water Associated with Construction Activity (General Construction Permit) for a construction site?
    Yes, both permits are needed because the Small MS4 Phase II Permit and the General Construction Permit are programmatically different. The Construction Site Storm Water Runoff Control Minimum Control Measure requires the municipality to develop and implement a program that provides local oversight of construction projects within the municipality to ensure that pollutants being discharged from construction sites into the MS4 are reduced. The program must include adopting an ordinance requiring storm water quality controls at construction sites, reviewing site plans, receiving comments from the public regarding the discharge of pollutants from construction sites, inspecting construction sites to ensure that pollutants are not being discharged in storm water runoff, and taking enforcement when necessary.  Also, the program must ensure that post-construction controls are implemented for those sites/cities that are subject to Attachment 4 of the Small MS4 Phase II Permit.

    The General Construction Permit requires a project to have a site specific SWPPP and to implement BMPs specific to activities at the construction site. The General Construction Permit directly regulates landowners engaged in construction involving land disturbance of one acre or more.  School construction and reconstruction resulting in more than one acre of disturbance must file a complete Notice of Intent (NOI) package and develop a Storm Water Pollution Prevention Plan (SWPPP) in accordance with Section A of the General Permit prior to the commencement of soil disturbing activities.

  3. Are there other storm water requirements I should be aware of?
    There may be other permits or requirements in addition to the Small MS4 Permit and the Construction General Permit.   For example, there may be specific requirements for erosion and sediment control contained in a local grading or erosion control ordinance.  You may also need a streambed alteration agreement from the Department of Fish and Game, a Water Quality Certification (Clean Water Act Section 401) as administered by the State and Regional Water Quality Control Boards, and/or Clean Water Act Section 404 permit administered by the U. S. Army Corps. of Engineers.  Contact the appropriate Regional Water Quality Control Board Staff to determine if other permits are required for your construction activity.

  4. Who should I contact if I have questions?
    Please email the State Water Board at stormwater@waterboards.ca.gov or call (916) 341-5537.  You may also contact the appropriate Regional Water Quality Control Board Staff.