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Storm Water - MS4 Municipal Program

Storm Water - MS4 Municipal Program

  • U.S. Department of Transportation Announces $500 Million in TIGER Discretionary Grants
    The U.S. Department of Transportation recently announced that the Transportation Investment Generating Economic Recovery (TIGER Discretionary Grant program) has up to $500 million available for capital projects related to highways, bridges, public transportation, rail, ports, and intermodal projects. A primary selection criterion specifically mentions addressing environmental sustainability including avoiding adverse environmental impacts to water quality, providing environmental benefits such as ground water recharge in areas of water scarcity, and stormwater mitigation, including green infrastructure. Applicants are encouraged to provide quantitative information, including baseline information that demonstrates how the project will reduce stormwater runoff. Eligible applicants are State, local, and tribal governments, transit agencies, port authorities, metropolitan planning organizations, other political subdivisions of State or local governments, and multi-State or multi-jurisdictional groups applying through a lead applicant. TIGER applications are due no later than April 29, 2016 at 8 PM E.D.T. Additional details and webinars: https://www.transportation.gov/tiger

  • NOTICE: The U.S. Environmental Protection Agency's (U.S. EPA) Urban Waters Small Grants program is currently requesting proposals. For more information please see the U.S. EPA's Urban Waters web page (http://www2.epa.gov/urbanwaters/urban-waters-small-grants-mapping)

Disclaimer and Notes:

The NPDES Permit pdf documents might be formatted differently than the hard copies. We are in the process of reformating the permit pdf files to match the format on the hard copies.

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MS4 Municipal Program Content


The Municipal Storm Water Permitting Program regulates storm water discharges from municipal separate storm sewer systems (MS4s). MS4 permits were issued in two phases.

  • Under Phase I, which started in 1990, the Regional Water Quality Control Boards have adopted National Pollutant Discharge Elimination System (NPDES) storm water permits for medium (serving between 100,000 and 250,000 people) and large (serving 250,000 or more people) municipalities. Most of these permits are issued to a group of Co -permittees encompassing an entire metropolitan area.

  • On April 30, 2003, as part of Phase II, the State Water Resources Control Board issued a General Permit for the Discharge of Storm Water from Small MS4s (WQ Order No. 2003-0005-DWQ) to provide permit coverage for smaller municipalities (population less than 100,000), including non-traditional Small MS4s, which are facilities such as military bases, public campuses, prisons and hospital complexes. The Phase II Small MS4 General Permit covers Phase II Permittees statewide. On February 5, 2013, the Phase II Small MS4 General Permit was renewed and became effective on July 1, 2013.

Region-wide Permit

The Central Valley Water Board adopted a Region-wide MS4 Permit (Region-wide Permit) on 23 June 2016. Phase I MS4 permittees shall enroll under the Region-wide Permit as their current Individual permits expire and Phase II MS4 Permittees may choose to enroll.

emailsubscription  To receive information and updates on upcoming meetings for the Region-wide Permit, please visit: http://www.waterboards.ca.gov/resources/email_subscriptions/reg5_subscribe.shtml. Provide your email address and name in the spaces provided and select "Storm Water Region-wide Permit" from the list of selections.

Stakeholder Meeting Process

Phase I MS4 Municipal Program

Phase II Small MS4 Program

Other Resources

Questions or Comments about MS4 Permits or the MS4 Program?

  • You may submit your MS4 questions or comments to Program Staff.

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--Web page updated 01/23/2017