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Corner of tabFlorida's NPDES Stormwater Program

Program for Municipal Separate Storm Sewer Systems (MS4s)


Photo of an MS4 OutfallA municipal separate storm sewer system (MS4) is a publicly-owned conveyance or system of conveyances (i.e., ditches, curbs, catch basins, underground pipes, etc.) that is designed or used for collecting or conveying stormwater and that discharges to surface waters of the State. An MS4 can be operated by municipalities, counties, drainage districts, colleges, military bases, or prisons, to name a few examples.

As implemented by Chapter 62-624, F.A.C., Phase I addresses discharges of stormwater runoff from "medium" and "large" MS4s (i.e., those MS4s located in areas with populations of 100,000 or greater). Under Phase II, the program regulates discharges from certain MS4s not regulated under Phase I, and that meet designation criteria set forth in Chapter 62-624, F.A.C. Regulated MS4 operators must obtain an NPDES stormwater permit and implement a comprehensive stormwater management program to reduce the contamination of stormwater runoff and prohibit illicit discharges to the MS4. Get a list of permitted Phase I (individual) and Phase II MS4 permits and contacts in Florida

The following links provide more detailed information

Phase I MS4s

  • Who's Covered: Provides the regulatory definitions of Phase I large and medium MS4s and a list of the Phase I MS4s currently permitted in Florida.
  • Permit Requirements: Outlines the stormwater management program requirements for Phase I large and medium MS4s and the permit re-application requirements.
  • Frequently Asked Questions (FAQs): Provides answers to the Phase I large and medium MS4s permit re-application questions most commonly posed to DEP.

Regulated Phase II MS4s

  • Who's covered:  Explains which Phase II MS4s are regulated under the program, including automatic designation and designation by the permitting authority.
  • Permit and Implementation Options: Permit Options & Requirements: Outlines the three options available to regulated Phase II MS4 operators for obtaining permit coverage. Also, details the permit application and stormwater management program requirements.

For more information, send us an e-mail
NPDES Stormwater Program
2600 Blair Stone Road  Mail Station 3585
Tallahassee, FL, 32399
Phone (850) 245-7522

Last updated: September 26, 2013

  2600 Blair Stone Road M.S. 3500   Tallahassee, Florida 32399   850-245-8336 (phone) / 850-245-8356 (fax) 
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