Press Release

BALTIMORE, MD (February 25, 2009) – Today the Maryland Department of Environment (MDE) issued its final determination for Montgomery County’s Municipal Separate Storm Sewer System (MS4) permit, required by the federal Clean Water Act. The final permit requires actions to eliminate the negative impacts of polluted stormwater runoff in Montgomery County, which has eight federally listed impaired waterways, and would be an important step toward cleaning up local waterways and restoring the Chesapeake Bay. Major new provisions include requiring restoration of an additional 20 percent of impervious surfaces (on top of 10 percent already required, for a total of 30 percent); developing and implementing measurable strategies to reduce trash as part of the County’s commitment to a trash-free Potomac River; and setting pollution limits necessary to meet water quality standards for impaired waters.

A draft permit published on September 2, 2008, was followed by a public hearing on November 19, 2008, where MDE received many verbal and written comments. The permit was modified after public comments to clarify the requirement that Total Maximum Daily Load (TMDL) implementation plans include actions and deadlines to meet Waste Load Allocations (WLAs) in federally approved TMDLs. The final permit should go into effect March 20, 2009.

Maryland Department of the Environment Deputy Secretary Bob Summers said: “While Maryland has taken bold steps in reducing pollution from wastewater treatment plants and agriculture, polluted stormwater runoff remains a challenge in our most populated areas. Montgomery County’s stormwater permit would significantly advance stormwater controls, which are critical to restoring our streams, rivers, and the Chesapeake Bay. This permit is one of the most progressive in the country and clearly demonstrates that Montgomery County and Maryland are serious about water quality.”
According to the latest estimates from the Chesapeake Bay Program, urban and suburban stormwater runoff accounts for 17 percent of Maryland’s nitrogen load to the bay. In the Middle Potomac Watershed, urban sources, excluding wastewater treatment plants, contribute over 30 percent of the nutrient load. Contaminants in runoff can rival or exceed the amount reaching local waterways from industries, federal facilities, and wastewater treatment plants.

To view this permit, along with MDE’s response to public comments, visit:

In addition to today’s permit, in January 2009 MDE issued a final determination for a general permit for stormwater related to construction activities that increases public participation, includes monitoring and plan review, and addresses several critical elements of site design and erosion and sediment controls. MDE is also finalizing proposed regulations to implement the Stormwater Management Act of 2007, which would require developers to use state-of-the-art Environmental Site Design practices wherever possible to control runoff and pollution from both new development and redevelopment. Combined, these new controls will cut current urban stormwater nutrient loads by 20 to 30 percent, resulting in a 3 to 4 percent reduction in the total load from Maryland to the Bay.

MDE also encourages property owners to reduce stormwater runoff and erosion by using permeable paving surfaces; planting trees, shrubs, and groundcover; allowing “buffer strips” near waterways; and limiting the use of chemical fertilizers and pesticides.

The press release has been edited after publication.