Department of Stormwater

The Department of Stormwater's mission is to monitor, protect, restore, and enhance Frederick County’s waterways. 

We work to improve our community’s quality of life, defend from climate-driven flooding, and contribute to the health of the Chesapeake Bay ecosystem. The Department of Stormwater ensures regulatory compliance through cost-effective decisions that provide the greatest community and environmental benefit. Please use the links on this page to learn more about our work and our public programs.

Our work is structured by requirements of the National Clean Water Act and administratively enforced by the State of Maryland under the National Pollutant Discharge Elimination System (NPDES) permit program. The State of Maryland issues two permit types to Frederick County to ensure it is abiding by the Clean Water Act: the Municipal Separate Storm Sewer System (MS4) permit and a General Permit for Discharges from Stormwater Associated with Industrial Activities permit (20-SW). The MS4 permit requires the County to perform permit and program administration, stream and forest restoration, and environmental enforcement to protect our waterways. 

We submit an annual report to the State of Maryland that details our MS4 Permit-related work. You can review the latest submission here.

  1. Municipal Separate Storm Sewer Permit

The Frederick County Department of Stormwater's work is structured by compliance with a Municipal Separate Storm Sewer System permit issued by the State of Maryland, also known as the “MS4.” That permit is required by a larger federal Clean Water Act program, the National Pollutant Discharge and Elimination System (NPDES). Our current MS4 Permit requires Frederick County to complete the restoration of 1,027 impervious equivalent acres and address pollutant load reductions for the Chesapeake Bay and local Total Maximum Daily Loads (TMDLs).  

What does that mean? This means there are regulated, legally-required activities we take that help us be good stewards of the environment, conserve valuable natural resources, improve the health of our waterways, and protect our community's infrastructure. Those activities must be measured and reported to the State to meet our mandated goals. 

To accomplish these goals, DEE must identify stormwater projects that receive the required impervious equivalent acre credits (see the Glossary of Terms on this page for more info) in accordance with the Maryland Department of Environment’s (MDE) Accounting for Stormwater Management guidance document.   On a large scale, this is accomplished through Watershed Assessments that identify multiple areas where there is a need for stormwater management. Then our staff completes more focused assessments through Feasibility Studies.