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Maryland State Government Maryland Department of the Environment

Maryland’s NPDES Municipal Separate Storm Sewer System (MS4) Permits

New! Tentative Determination to Issue Stormwater Permit for Frederick County

MDE has reached a tentative determination to issue an NPDES permit to Frederick County to control storm drain system pollutant discharges. MDE has drafted a permit designed to comply with the United States Environmental Protection Agency’s (EPA) regulations and to control stormwater pollutant discharges from the County’s storm drain system. The permit is issued for five years.

Under the conditions of the permit, the County is required to possess the legal authority to control storm drain system pollutants, continue mapping its storm sewer system, monitor stormwater discharges, and develop and implement comprehensive management programs. The permit also requires increases in impervious area treatment goals, the development of litter control programs, and the implementation of environmental site design for new and redevelopment projects to the maximum extent practicable. The County is also required to develop and implement plans to address stormwater waste load allocations established under EPA approved total maximum daily loads. Penalties for failure to comply with the terms of the permit are provided.

This permit and a fact sheet may be viewed here:

Draft NPDES Permit for Frederick County
Fact Sheet concerning the Frederick County NPDES Permit

For more information concerning this permit, please contact Mr. Raymond Bahr at 410-537-3543 or 1-800-633-6101 or by email at Raymond.Bahr@maryland.gov. Copies of the document may be procured at a cost of 36¢ per page.

MDE held a public hearing concerning the tentative determination to issue the stormwater permit for Frederick County on August 28, 2014. MDE also accepted public comments on the Frederick County stormwater permit through September 29, 2014. Written comments received before September 29, 2014 may be viewed here:

New! Tentative Determination to Issue Stormwater Permit for Carroll County

MDE has reached a tentative determination to issue an NPDES permit to Carroll County to control storm drain system pollutant discharges. MDE has drafted a permit designed to comply with the United States Environmental Protection Agency’s (EPA) regulations and to control stormwater pollutant discharges from the County’s storm drain system. The permit is issued for five years.

Under the conditions of the permit, the County is required to possess the legal authority to control storm drain system pollutants, continue mapping its storm sewer system, monitor stormwater discharges, and develop and implement comprehensive management programs. The permit also requires increases in impervious area treatment goals, the development of litter control programs, and the implementation of environmental site design for new and redevelopment projects to the maximum extent practicable. The County is also required to develop and implement plans to address stormwater waste load allocations established under EPA approved total maximum daily loads. Penalties for failure to comply with the terms of the permit are provided.

This permit and a fact sheet may be viewed here:

Draft NPDES Permit for Carroll County
Fact Sheet concerning the Carroll County NPDES Permit

For more information concerning this permit, please contact Mr. Raymond Bahr at 410-537-3543 or 1-800-633-6101 or by email at Raymond.Bahr@maryland.gov. Copies of the document may be procured at a cost of 36¢ per page.

MDE held a public hearing concerning the tentative determination to issue the stormwater permit for Carroll County on September 8, 2014. MDE also accepted public comments on the Carroll County stormwater permit through September 29, 2014. Written comments received before September 29, 2014 may be viewed here:

New! Tentative Determination to Issue Stormwater Permit for Charles County

MDE has reached a tentative determination to issue an NPDES permit to Charles County to control storm drain system pollutant discharges. MDE has drafted a permit designed to comply with the United States Environmental Protection Agency’s (EPA) regulations and to control stormwater pollutant discharges from the County’s storm drain system. The permit is issued for five years.

Under the conditions of the permit, the County is required to possess the legal authority to control storm drain system pollutants, continue mapping its storm sewer system, monitor stormwater discharges, and develop and implement comprehensive management programs. The permit also requires increases in impervious area treatment goals, the development of litter control programs, and the implementation of environmental site design for new and redevelopment projects to the maximum extent practicable. The County is also required to develop and implement plans to address stormwater waste load allocations established under EPA approved total maximum daily loads. Penalties for failure to comply with the terms of the permit are provided.

This permit and a fact sheet may be viewed here:

Draft NPDES Permit for Charles County
Fact Sheet concerning the Charles County NPDES Permit

For more information concerning this permit, please contact Mr. Raymond Bahr at 410-537-3543 or 1-800-633-6101 or by email at Raymond.Bahr@maryland.gov. Copies of the document may be procured at a cost of 36¢ per page.

MDE held a public hearing concerning the tentative determination to issue the stormwater permit for Charles County on September 4, 2014. MDE also accepted public comments on the Charles County stormwater permit through September 26, 2014. Written comments received before September 26, 2014 may be viewed here:

New! Tentative Determination to Issue Stormwater Permit for Harford County

MDE has reached a tentative determination to issue an NPDES permit to Harford County to control storm drain system pollutant discharges. MDE has drafted a permit designed to comply with the United States Environmental Protection Agency’s (EPA) regulations and to control stormwater pollutant discharges from the County’s storm drain system. The permit is issued for five years.

Under the conditions of the permit, the County is required to possess the legal authority to control storm drain system pollutants, continue mapping its storm sewer system, monitor stormwater discharges, and develop and implement comprehensive management programs. The permit also requires increases in impervious area treatment goals, the development of litter control programs, and the implementation of environmental site design for new and redevelopment projects to the maximum extent practicable. The County is also required to develop and implement plans to address stormwater waste load allocations established under EPA approved total maximum daily loads. Penalties for failure to comply with the terms of the permit are provided.

This permit and a fact sheet may be viewed here:

Draft NPDES Permit for Harford County
Fact Sheet concerning the Harford County NPDES Permit

For more information concerning this permit, please contact Mr. Raymond Bahr at 410-537-3543 or 1-800-633-6101 or by email at Raymond.Bahr@maryland.gov. Copies of the document may be procured at a cost of 36¢ per page.

MDE held a public hearing concerning the tentative determination to issue the stormwater permit for Harford County on September 5, 2014. MDE also accepted public comments on the Harford County stormwater permit through September 26, 2014. Written comments received before September 26, 2014 may be viewed here:

New! Tentative Determination to Issue Stormwater Permit for Howard County

MDE has reached a tentative determination to issue an NPDES permit to Howard County to control storm drain system pollutant discharges. MDE has drafted a permit designed to comply with the United States Environmental Protection Agency’s (EPA) regulations and to control stormwater pollutant discharges from the County’s storm drain system. The permit is issued for five years.

Under the conditions of the permit, the County is required to possess the legal authority to control storm drain system pollutants, continue mapping its storm sewer system, monitor stormwater discharges, and develop and implement comprehensive management programs. The permit also increases impervious area treatment goals, requires the implementation of litter control programs and environmental site design for new and redevelopment projects to the maximum extent practicable. The County is also required to develop and implement plans to address waste load allocations established under EPA approved total maximum daily loads. Penalties for failure to comply with the terms of the permit are provided.

This permit and a fact sheet may be viewed here:

Draft NPDES Permit for Howard County
Fact Sheet concerning the Howard County NPDES Permit

For more information concerning this permit, please contact Mr. Raymond Bahr at 410-537-3543 or 1-800-633-6101 or by email at Raymond.Bahr@maryland.gov. Copies of the document may be procured at a cost of 36¢ per page.

MDE accepted public comments on the tentative determination to issue the stormwater permit for Howard County through July 23, 2014. Written comments received before July 23, 2014 may be viewed here:

Final Determination to Issue Stormwater Permit to Anne Arundel County (February 10, 2014)

The Maryland Department of the Environment (MDE) has reached a final determination to reissue a National Pollutant Discharge Elimination System (NPDES) stormwater permit to Anne Arundel County, Maryland. This permit covers stormwater discharges from the storm drain system owned or operated by Anne Arundel County. Permit requirements include implementing comprehensive stormwater management programs for addressing runoff from new and redevelopment projects, restoring urban areas where there is currently little or no stormwater management, and working toward meeting stormwater waste load allocations for local water resources and Chesapeake Bay. Also included in the permit are conditions that require the County to possess the necessary legal authority to control stormwater discharges,map its storm drain system, monitor urban runoff, and eliminate illicit discharges to the storm drain system. MDE has met with various stakeholders over the past several years regarding this permit, held a public hearing to accept testimony on August 7, 2013, and accepted public comments through August 19, 2013. It is MDE's final determination that this permit complies with the United States Environmental Protection Agency’s NPDES regulations to control stormwater pollutant discharges from Anne Arundel County’s storm drain system to the maximum extent practicable. MDE's final determination is subject to judicial review at the request of any person that meets the threshold standing requirements under federal law and participated in the public participation process through the submission of written or oral comments. The final determination may be found on MDE's web site at www.mde.maryland.gov or by contacting Mr. Brian Clevenger, Maryland Department of the Environment, 1800 Washington Blvd., Suite 440, Baltimore, Maryland 21230-1708, or call (410) 537-3543. Requests for judicial review in accordance with §1-601 and §1-605 of the Environment Article need to be made on or before March 14, 2014.

This permit and the Basis for Final Determination may be viewed here:

Written testimony and comments received during the Public Hearing held on August 7, 2013, and written comments received before August 19, 2013 may be viewed here:

Anne Arundel County NPDES Phase I MS4 Permit

Final Determination to Issue Stormwater Permit to Prince George's County (January 2, 2014)

The Maryland Department of the Environment (MDE) has reached a final determination to reissue a National Pollutant Discharge Elimination System (NPDES) stormwater permit to Prince George’s County, Maryland. This permit covers stormwater discharges from the storm drain system owned or operated by Prince George’s County. Permit requirements include implementing comprehensive stormwater management programs for addressing runoff from new and redevelopment projects, restoring urban areas where there is currently little or no stormwater management, and working toward meeting stormwater waste load allocations for local water resources and Chesapeake Bay. Also included in the permit are conditions that require the County to possess the necessary legal authority to control stormwater discharges, map its storm drain system, monitor urban runoff, and eliminate illicit discharges to the storm drain system. MDE has met with various stakeholders over the past several years regarding this permit, held a public hearing to accept testimony on June 5, 2013, and accepted public comments through June 27, 2013. It is MDE's final determination that this permit complies with the United States Environmental Protection Agency’s NPDES regulations to control stormwater pollutant discharges from Prince George’s County’s storm drain system to the maximum extent practicable. MDE's final determination is subject to judicial review at the request of any person that meets the threshold standing requirements under federal law and participated in the public participation process through the submission of written or oral comments. The final determination may be found on MDE's web site at www.mde.maryland.gov or by contacting Mr. Brian Clevenger, Maryland Department of the Environment, 1800 Washington Blvd., Suite 440, Baltimore, Maryland 21230-1708, or call (410) 537-3543. Requests for judicial review in accordance with §1-601 and §1-605 of the Environment Article need to be made on or before February 3, 2014.

This permit and the Basis for Final Determination may be viewed here:

Written testimony and comments received during the Public Hearing held on May 15, 2013, and written comments received before June 27, 2013 may be viewed here:

Final Determination to Issue Stormwater Permit to Baltimore City (December 27, 2013)

The Maryland Department of the Environment (MDE) has reached a final determination to reissue a National Pollutant Discharge Elimination System (NPDES) stormwater permit to Baltimore City, Maryland. This permit covers stormwater discharges from the storm drain system owned or operated by Baltimore City. Permit requirements include implementing comprehensive stormwater management programs for addressing runoff from new and redevelopment projects, restoring urban areas where there is currently little or no stormwater management, and working toward meeting stormwater waste load allocations for local water resources and Chesapeake Bay. Also included in the permit are conditions that require the City to possess the necessary legal authority to control stormwater discharges, map its storm drain system, monitor urban runoff, and eliminate illicit discharges to the storm drain system. MDE has met with various stakeholders over the past several years regarding this permit, held a public hearing to accept testimony on August 7, 2012, and accepted public comments through September 21, 2012. It is MDE's final determination that this permit complies with the United States Environmental Protection Agency’s NPDES regulations to control stormwater pollutant discharges from Baltimore City’s storm drain system to the maximum extent practicable. MDE's final determination is subject to judicial review at the request of any person that meets the threshold standing requirements under federal law and participated in the public participation process through the submission of written or oral comments. The final determination may be found on MDE's web site at www.mde.maryland.gov or by contacting Mr. Brian Clevenger, Maryland Department of the Environment, 1800 Washington Blvd., Suite 440, Baltimore, Maryland 21230-1708, or call (410) 537 -3543. Requests for judicial review in accordance with §1-601 and §1-605 of the Environment Article need to be made on or before January 26, 2014.

This permit and the Basis for Final Determination may be viewed here:

Written testimony and comments received during the Public Hearing held on August 7, 2012, and written comments received before September 21, 2012 may be viewed here:

Final Determination to Issue Stormwater Permit to Baltimore County (December 23, 2013)

The Maryland Department of the Environment (MDE) has reached a final determination to reissue a National Pollutant Discharge Elimination System (NPDES) stormwater permit to Baltimore County, Maryland. This permit covers stormwater discharges from the storm drain system owned or operated by Baltimore County. Permit requirements include implementing comprehensive stormwater management programs for addressing runoff from new and redevelopment projects, restoring urban areas where there is currently little or no stormwater management, and working toward meeting stormwater waste load allocations for local water resources and Chesapeake Bay. Also included in the permit are conditions that require the County to possess the necessary legal authority to control stormwater discharges, map its storm drain system, monitor urban runoff, and eliminate illicit discharges to the storm drain system. MDE has met with various stakeholders over the past several years regarding this permit, held a public hearing to accept testimony on July 26, 2013, and accepted public comments through July 10, 2013. It is MDE's final determination that this permit complies with the United States Environmental Protection Agency’s NPDES regulations to control stormwater pollutant discharges from Baltimore County’s storm drain system to the maximum extent practicable. MDE's final determination is subject to judicial review at the request of any person that meets the threshold standing requirements under federal law and participated in the public participation process through the submission of written or oral comments. The final determination may be found on MDE's web site at www.mde.maryland.gov or by contacting Mr. Brian Clevenger, Maryland Department of the Environment, 1800 Washington Blvd., Suite 440, Baltimore, Maryland 21230-1708, or call (410) 537-3543. Requests for judicial review in accordance with §1-601 and §1-605 of the Environment Article need to be made on or before January 22, 2014.

This permit and the Basis for Final Determination may be viewed here:

Written testimony and comments received during the Public Hearing held on June 26, 2013, and written comments received before July 10, 2013 may be viewed here:

NPDES Phase I Permits

The Environmental Protection Agency’s (EPA) National Pollutant Discharge Elimination System (NPDES) stormwater regulations were published in 1990. Phase I of these regulations require large urban jurisdictions to control pollution in stormwater to the maximum extent practicable (MEP). For permitting purposes, municipalities with populations of greater than 250,000 are considered “large” and those with populations of between 100,000 and 250,000 as “medium.” Municipalities with less than 100,000 are handled separately under Phase II NPDES stormwater rules discussed below (cli ck here to learn more about Phase II). After receiving applications from Phase I municipalities in 1991 and 1992, MDE began issuing NPDES municipal stormwater permits in 1993. These permits are updated every five years. You can view background information on each jurisdiction by clicking on the municipality's name in the chart below. Initial permits, current permits, and links to the agency responsible for administering each local permit are also accessible by clicking on the respective links below.

Initial Permit Issued Current Permit Issued Local Agency Responsible for Annual Reporting

Large Jurisdictions

Anne Arundel County

12/02/1993

02/12/2014

Dept. of Public Works / Watershed Ecosystem and Restoration

Baltimore County

11/17/1994

12/23/2013

Dept. of Environmental Protection & Sustainability (EPS) / NPDES

Baltimore City

11/17/1993

12/27/2013

Dept. of Public Works

Montgomery County

03/15/1996

02/16/2010

Dept. of Environmental Protection

Prince George’s County

11/17/1993

01/02/2014

Dept. of Environmental Resources

Medium Jurisdictions

Carroll County

11/17/1993

07/14/2005

Land Use, Planning & Development

Charles County

05 /01/1997

07/31/2002

Planning & Growth Management

Frederick County

11/15/1994

03/11/2002

Sustainable Development - Watershed Management

Harford County

05/17/1994

11/01/2004

Dept. of Public Works - Water Resources

Howard County

04/17/1995

06/20/2005

Dept. of Public Works / Stormwater Management Division

State Storm Drain Systems

State Highway Administration

01/08/1999

10/21/2005

Not Available

Summary of Local Requirements

NPDES municipal stormwater permits require the jurisdictions to develop comprehensive programs to reduce storm drain system pollution to the MEP. Typical NPDES stormwater permit conditions require jurisdictions to:

  • Legal Authority: provide certification from appropriate legal counsel that adequate authority exists to control discharges from the municipal storm drain system
  • Source Identification: map storm drain pipes and best management practices (BMPs), land use, impervious cover, and watershed restoration projects in geographical information system (GIS) format
  • Management Programs: implement erosion and sediment control, stormwater management, illicit connection detection and elimination, and public education and outreach programs
  • Watershed Assessment: evaluate all urban watersheds thoroughly regarding water quality and develop goals and action plans for restoration,
  • Restoration Projects: restore between 10% and 20% of uncontrolled impervious surfaces based on watershed assessments during each five-year permit cycle
  • Assessment of Control: document work toward meeting watershed restoration goals, including total maximum daily loads (TMDLs)*, using chemical, biological, and physical monitoring
  • Program Funding: provide an annual fiscal analysis of the capital, operation, and maintenance expenditures necessary to comply with permit conditions

More information on TMDLs may be found on MDE's webpage here: Introduction to TMDLs

Maryland’s NPDES Municipal Stormwater Permits - Phase II

In December 1999, the EPA promulgated NPDES Phase II stormwater requirements. As a result, many of the localities and State and federal agencies not permitted under Phase I were required to obtain NPDES permit coverage under the federal Clean Water Act (CWA). Approximately 60 cities and towns in Maryland with populations greater than 1,000 have been designated for coverage by EPA or the MDE. Each Phase II municipality is required to implement the following six minimum measures: public education and outreach; public participation and involvement; illicit discharge detection and elimination; construction site runoff control; post- construction runoff control; and pollution prevention/good housekeeping. Implementation of these minimum control measures will help efforts toward improving the quality of Maryland’s streams, rivers, and Chesapeake Bay through the continued improvement of stormwater management and erosion and sediment control programs; the removal of illicit discharges; and public education.

To provide coverage to Phase II municipalities, MDE adopted a general permit on April 14, 2003 that addresses the six minimum control measures. Application requirements, measurable goals, BMP implementation schedules, and annual reporting requirements are addressed as well. A copy of the general permit may be found here:

NPDES Phase II General Permit

MDE has received the following Notices of Intent for coverage under the NPDES Phase II stormwater general permit.

Municipality

County Name

Cecil County

Cecil

Washington County Washington
Aberdeen Harford

Annapolis

Anne Arundel

Bel Air

Harford

Berwyn Heights

Prince George's

Bladensburg

Prince George's

Bowie

Prince George's

Brentwood

Prince George's

Brunswick

Frederick

Capitol Heights

Prince George's

Cheverly

Prince George's

College Park

Prince George's

Colmar Manor

Prince George's

Cottage City

Prince George's

District Heights

Prince George's

Elkton

Cecil

Emmitsburg

Frederick

Fairmount Heights

Prince George's

Forest Heights

Prince George's

Frederick

Frederick

Gaithersburg

Montgomery

Glenarden

Prince George's

Greenbelt

Prince George's

Hagerstown

Washington

Hampstead

Carroll

Havre de Grace

Harford

Hyattsville

Prince George's

Landover Hills

Prince George's

Laurel

Prince George's

Manchester

Carroll

Middletown

Frederick

Morningside

Prince George's

Mount Airy

Carroll

Mount Rainier

Prince George's

Myersville

Frederick

New Carrollton

Prince George's

New Windsor

Carroll

Riverdale Park

Prince George's

Rockville

Montgomery

Salisbury

Wicomico

Seat Pleasant

Prince George's

Smithsburg

Washington

Sykesville

Carroll

Takoma Park

Montgomery

Taneytown

Carroll

Thurmont

Frederick

Union Bridge

Carroll

University Park

Prince George's

Walkersville

Frederick

Westminster

Carroll

State and Federal Agencies

To provide coverage to State and federal agencies, MDE adopted a general permit on November 12, 2004 that addresses the six minimum control measures. Application requirements, measurable goals, BMP implementation schedules, and annual reporting requirements are addressed as well. A copy of the general permit may be found here:

General Permit for State and Federal Agencies

MDE has received the following NOI's for coverage under the NPDES Phase II Stormwater General Permit for Discharges from State and Federal Small MS4s:

Agency Installation/Facility Date Listed Date Authorized
Maryland Army National Guard Multiple Properties 01/03/2005 pending
Federal Law Enforcement Training Center Cheltenham 01/03/2005 09/29/2005
U.S. Department of the Army Fort Detrick 01/03/2005 09/20/2005
U.S. Department of the Air Force Andrews Air Force Base 01/10/2005 09/15/2005
U.S. Department of the Army Adelphi Laboratory Center 01/12/2005 09/20/2005
Washington Suburban Sanitary Commission Multiple Properties 01/12/2005 09/19/2005
United States Department of Agriculture APHIS-PPQ National Plant Germplasm & Biotechnology Laboratory 01/14/2005 10/27/2005
Maryland Aviation Administration Martin State Airport 01/14/2005 09/08/2005
National Institutes of Health Bethesda Campus 01/14/2005 10/07/2005
University of Maryland College Park Campus 01/14/2005 10/20/2005
Towson University Towson Campus 01/14/2005 10/04/2005
United States Postal Service William F. Bolger Center 01/14/2005 09/15/2005
Maryland Transit Administration Multiple Properties 01/14/2005 09/28/2005
National Aeronautics & Space Administration Goddard Space Flight Center 01/14/2005 10/04/2005
U.S. Department of the Navy Naval District Washington, Indian Head 01/18/2005 09/29/2005
U.S. Department of the Navy National Naval Medical Center 01/18/2005 09/28/2005
U.S. Department of the Army U.S. Army Garrison, Aberdeen Proving Ground 01/18/2005 09/28/2005
Maryland Air National Guard Multiple Properties 01/18/2005 pending
Architect of the Capitol Library of Congress at Fort Meade 01/18/2005 09/29/2005
Maryland State Highway Administration Multiple (outside Phase I Jurisdictions) 01/18/2005 05/25/2005
Washington Metropolitan Area Transit Authority Multiple Metro Rail Stations 01/25/2005 10/27/2005
U.S. Department of the Army Washington Aqueduct 01/25/2005 10/24/2005
Maryland Transportation Authority Multiple Properties 01/25/2005 09/08/2005
U.S. Department of the Navy U.S. Naval Academy 01/25/2005 10/20/2005
U.S. Department of the Navy Naval Surface Warfare Center, Carderock 02/01/2005 10/27/2005
U.S. Department of Commerce, National Institute of Standards & Technology (NIST) Gaithersburg Campus 02/01/2005 10/24/2005
Maryland Department of General Services Ellicott City District Court & John R. Hargrove District Court 02/17/2005 10/07/2005
U.S. Department of the Army Fort Meade 02/17/2005 10/07/2005
Maryland Stadium Authority Camden Yards Sports Complex 02/17/2005 10/27/2005
U.S. Department of the Army, Reserves Multiple Properties 11/14/2005 01/05/2006
U.S. Department of Defense Fort Meade 08/29/2008 10/27/2008
U.S. Department of Agriculture Beltsville Agricultural Research Center 10/24/2008 03/27/2009
Maryland Department of Transportation Motor Vehicle Administration Glen Burnie Headquarters 03/13/2009 05/29/2009
Maryland Department of Transportation Motor Vehicle Administration Multiple Properties 05/14/2009 07/02/2009
Maryland Department of Transportation Maryland Port Administration Multiple Properties 09/17/2009 04/05/2010
M-NCPPC Montgomery County Department of Parks Multiple Properties 11/12/2009 03/24/2010

Questions about NPDES municipal permits may be directed the Sediment, Stormwater, and Dam Safety Program at 410-537-3543 or emailed to Mr Raymond Bahr at Raymond.Bahr@maryland.gov.