Jump to main content.


Stormwater Permits

Mid-Atlantic Stormwater Quick Finder

Stormwater HomeContacts DroughtEnforcement FloodingPermits - MS4s Success Stories
What is an MS4?

A municipal separate storm sewer system.

A conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains):

District of Columbia MS4 Green Infrastructure Enhancement

On this page

Which discharges need permits? The NPDES stormwater permit regulations, put into law by the EPA, cover 3 classes of stormwater discharges on a nationwide basis:

Municipal Separate Storm Sewer Systems (MS4s)

Industrial

Construction



Mid-Atlantic Municipalities With Separate Storm Sewer (MS4) Permits
State
Permitting Authority
Permit Name
Phase*
Delaware
DE DNREC
New Castle County
I
DE DNREC
Del DOT
II
DE DNREC
City of Newark
II
DE DNREC
City of Dover
II
EPA Region 3
Dover Air Force Base
II
District of Columbia
EPA Region 3
District of Columbia
I
Maryland
MD DOE
Anne Arundel County
I
MD DOE
Baltimore City
I
MD DOE
Harford County
I
MD DOE
Prince George's County
I
MD DOE
Baltimore County
I
MD DOE
Carroll County
I
MD DOE
Charles County
I
MD DOE
Frederick County
I
MD DOE
Howard County
I
MD DOE
Montgomery County
I
MD DOE
MD State Highway Administration
II
MD DOE
Statewide Small MS4
II
MD DOE Statewide Small MS4 (State & Federal Facilities)
II
Pennsylvania
PA DEP
Philadelphia
I
PA DEP
Allentown
I
PA DEP
PA DOT
II
PA DEP PA Turnpike Commission
II
PA DEP
Statewide Small MS4
II
Virginia
VA DEQ
Arlington County
I
VA DEQ Fairfax County
I
VA DEQ Prince William County
I
VA DEQ Chesterfield County
I
VA DEQ Henrico County
I
VA DEQ Chesapeake City
I
VA DEQ Hampton City
I
VA DEQ Newport News
I
VA DEQ Norfolk City
I
VA DEQ Portsmouth City
I
VA DEQ Virginia Beach City
I
VA DEQ Statewide Small MS4
II
West Virginia WV DEP Statewide Small MS4
II

*
Phase I - sources of stormwater runoff that have the greatest potential to negatively impact water quality

Phase II - stormwater discharges from:

  • certain regulated small municipal separate storm sewer systems (MS4s) and
  • construction activity disturbing between 1 and 5 acres of land

EPA Water Home || Mid-Atlantic Water Home
Mid-Atlantic Water Topics A - Z


Local Navigation


water for kids

Jump to main content.