At a Glance

With the work carried out under this project effort, Montgomery County is leading the way in Maryland and the Chesapeake Bay region on implementing integrated watershed and stormwater management approaches to achieve water quality and habitat targets required under the latest generation of regulatory permits.

Project Description

Under an Environmental Restoration Services contract with Montgomery County Department of Environmental Protection (DEP), Biohabitats is providing services for a two-part assignment related to meeting the requirements of the County’s third-round National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit. The first part focuses on the development of a coordinated watershed implementation strategy. Biohabitats developed detailed implementation plans for seven of the county’s watershed groupings using desktop analysis, detailed pollutant loading modeling (including bacteria) and a process of exploring the full restoration potential of each watershed area. Then a prioritization effort was developed that balanced permit requirements, stakeholder input, and cost/benefit output tied to projected funding levels.  The final output yielded a countywide strategy that meets: 1) short term permit requirements such as treating specified amounts of untreated impervious surface; 2) Chesapeake Bay Total Maximum Daily Load (TMDL) targets for nutrient and sediment load reduction; and 3) longer term local watershed TMDLs, including a bacteria TMDL for Rock Creek. As part of their MS4 permit, Montgomery County was responsible for reducing the bacterial load from wildlife and domestic pets in the watershed.

The second part of the project involved developing recommendations to implement Environmental Site Design/Low impact Design (ESD/LID) techniques to the Maximum Extent Practicable (MEP) to meet the permit requirements. Biohabitats assessed the County’s existing laws and regulations concerning stormwater management and water resources protection; identified any potential barriers, gaps, and deficiencies; and provided recommendations to promote the use of ESD/LID techniques to the MEP.



Chesapeake/Delaware Bays

Physiographic Province



Anacostia River and Potomac River

Expertise Areas

Conservation, Infrastructure, Urban Ecology


Montgomery County Department of Environmental Protection


Montgomery County, Maryland, United States