Municipal Separate Storm Sewer System (MS4) Permit

The Maryland Department of Transportation State Highway Administration (MDOT SHA) controls storm drain system pollutants along MDOT SHA roads. We do the following:

  • map our storm drain system
  • assess the effectiveness of restoration projects through chemical, physical and biological monitoring
  • implement comprehensive management programs for -
    • stormwater management
    • erosion and sediment control
    • illicit discharge detection and elimination
    • public education and outreach
    • property management and maintenance

In 2015 MDOT SHA received an NPDES MS4 permit (No. 11-DP-3313) from the Maryland Department of the Environment (MDE) to control storm-drain-system pollutant discharges in MS4-designated areas (see map below). The permit requires that we use restoration practices to treat 20% of existing MDOT SHA impervious surfaces and address stormwater wasteload allocations (WLAs) established under US Environmental Protection Agency (EPA)-approved Total Maximum Daily Loads (TMDL).

MS4 Phase 1 Permit Coverage map

IMPERVIOUS RESTORATION AND COORDINATED TMDL IMPLEMENTATION PLAN

Part I – Program Introduction (10/09/2018) (PDF, 4.8 MB)
Part II – Impervious Restoration Plan & Chesapeake Bay TMDL Compliance (10/08/2016) (PDF, 3.1 MB)
Part III – Coordinated TMDL Implementation Plan (10/09/2018) (PDF, 3.4 MB)
Part IV – MDOT SHA Watershed TMDL Implementation Plans (10/09/2018) (PDF, 56.8 MB)
Entire Plan without Part II (10/09/2018) (PDF, 64 MB)

2019 TMDL IMPLEMENTATION PLANS

Other West Chesapeake Watershed Sediment TMDL Implementation Plan (PDF)
Non-Tidal Back River Watershed Sediment TMDL Implementation Plan (PDF)
Non-Tidal Patuxent River Lower Watershed Sediment TMDL Implementation Plan (PDF)
Non-Tidal Patuxent River Middle Watershed Sediment TMDL Implementation Plan (PDF)

REVIEW AND COMMENT ON DRAFT IMPLEMENTATION PLANS

Review latest draft MDOT SHA TMDL implementation plan.

CURRENT MS4 PERMIT AND ANNUAL REPORTS

MDOT SHA MS4 Permit Issued October 9, 2015 (PDF,  551 KB)
2018 Annual Report (PDF, 125 MB)
2017 Annual Report (PDF, 500 MB)
2016 Annual Report (PDF, 91.9 MB)

RELATED DOCUMENTS

MDOT SHA Existing Water Quality Grass Swale Identification Protocol (PDF, 3.22 MB)
MDOT SHA Alternative Headwater Channel and Outfall Crediting Protocol (PDF, 11 MB)
MDOT SHA Automated Modeling Protocol Revised (PDF, 476 KB)

PREVIOUS MS4 PERMIT AND ANNUAL REPORTS

MDOT SHA MS4 Permit Issued October 21, 2005 (PDF, 1.93 MB)
2015 Annual Report (PDF, 7.37 MB)
2014 Annual Report (PDF, 13 MB)
2013 Annual Report (PDF, 8.99 MB)
2012 Annual Report (PDF, 25.8 MB)
2011 Annual Report (PDF, 2.57 MB)
2010 Annual Report (PDF, 23.4 MB)
2009 Annual Report (PDF, 13.1 MB)
2008 Annual Report (PDF, 41.7 MB)
2007 Annual Report (PDF, 17.7 MB)
2006 Annual Report (PDF, 18.6 MB)