Municipal Separate Storm Sewer System (MS4) Permit Program

What is a MS4?
MS4 is short for municipal separate storm sewer system. The MS4 Permit Program is a program that ensures county-owned and operated storm sewer systems meet state water control board and United State Environmental Protection Agency (EPA) requirements. Generally, MS4 permits are required for medium and large cities or counties with a population of 100,000 citizens or more in an urbanized area. The permit allows municipalities to discharge stormwater to state waterways. MS4 permits are a type of National Pollutant Discharge Elimination System (NPDES) permit.

Storm sewer systems collect and convey stormwater and are separate from sanitary sewer systems. Unlike sanitary sewer, which flows to a treatment facility to be cleaned before discharging to a natural waterway, stormwater is not treated before it is discharged into a waterway. Maintaining a compliant program prevents harmful pollutants from entering waterways within the county.

Stafford County’s MS4 Program
The County is designated as a Phase II (small) MS4, according to the U.S. Environmental Protection Agency’s MS4 Stormwater Permit Program. The County was issued a General Permit for Discharges of Stormwater by the Virginia Department of Environmental Quality (DEQ) on October 29, 2018 and will expire on October 31, 2023.

Stafford MS4 Permit
Under the general permit, small MS4s must develop, implement and enforce a program that includes the following “six minimum control measures":

  1. Public education and outreach on stormwater impacts
  2. Public involvement and participation
  3. Illicit discharge detection and elimination
  4. Construction site stormwater runoff control
  5. Post-construction stormwater management in new development and redevelopment
  6. Pollution prevention/good housekeeping for municipal operations

The County’s efforts to control stormwater within urban areas is defined in the MS4 Program Plan and Pubic Education and Outreach Plan.


A paper copy of the 2018-23 Program Plan is available at 2126 Richmond Highway, Suite 203, Stafford, VA 22554.

The permit requirements include allowing the public an opportunity to provide input on the program plan. To submit input and comments, please contact the Environmental Division by phone or email.

High-Priority Stormwater Issues
In order to comply with the MS4 general permit, the County identified pet waste, residential lawn care, and illicit discharge as the high priority stormwater issues to address as part of its Public Education and Outreach Program.
The County selected pet waste as a high priority stormwater issue because pet waste is known to contain high volumes of bacteria and the 2016 305(b)/303(d) Water Quality Assessment Integrated Report identified bacteria as a cause of impairment for numerous receiving waters downstream of the County’s MS4 service area in both the Potomac River and Rappahannock River basins.

The County selected residential lawn care as a high priority stormwater issue because EPA has identified improper nutrient application on residential lawns as a source of nutrients that contribute to the Chesapeake Bay impairments.

The County selected illicit discharge, in general, as a high-priority stormwater issue because EPA identified eliminating illicit discharges has been identified by EPA as one of the six minimum control measures necessary for MS4 operators to implement in order to reduce pollutants from MS4s to the maximum extent practicable. The general public is not only the eyes and ears for reporting illicit discharges to the County, they are the main source of the illicit discharge, either at home or at work.

TMDL Action Plan
A Total Maximum Daily Load (TMDL) is the calculated maximum amount of a particular pollutant a waterbody can receive without exceeding water quality standards. Implementation of TMDLs are a requirement of section 303(d) of the Clean Water Act. The Commonwealth of Virginia is required to establish TMDLs for waterbodies that are declared impaired for certain pollutants. Localities receive allocations for those pollutants under a TMDL and are required to create an action plan for each TMDL. The TMDL action plan is a document that outlines management and restoration initiatives aimed to reduce the amount of a particular pollutant for a designated body of water.

Stafford County's 2019 Chesapeake Bay TMDL Action Plan
2020 Bacteria TMDL Action Plan
Stafford County's 2023 Draft TMDL Action Plan

Annual Reports
Stafford County is required to provide an Annual Report during the term of the MS4 Stormwater General Permit (2018-2023). This Annual Report is submitted to the Virginia Department of Environmental Quality (DEQ) and describes the County's yearly progress towards meeting the requirements of the Permit.

MS4 Program Partner Organizations
Friends of the Rappahannock (FOR) MOU
Northern Virginia Regional Commission (NVRC) MOU
Friends of Rappahannock - https://riverfriends.org
Northern Virginia Regional Commission - https://www.novaregion.org/190/Environmental-Programs-and-Projects

St. Clair Brooks Park Stream Restoration Project
Information about the St. Clair Brooks Park Stream Restoration Project can be found here

Please report potential illicit discharges, improper disposal or spills to the MS4, complaints regarding land disturbing activities, or oth-er potential stormwater pollution concerns by using "Report Water Pollution" under "Report Violations" using AskBlu. Alternatively, you can call 540-658-8830.