Frequently Asked Questions - NPDES
"What is the NPDES program?"
NPDES stands for National Pollutant Discharge Elimination System. It is a federal program out of the Environmental Protection Agency (EPA) that regulates pollution through permits. While the County has several NPDES permits, our biggest one is the countywide MS4 permit, which is managed by the Department of Planning and Land Management.
"What is an MS4 permit?"
MS4 stands for Municipal Separate Storm Sewer System. Within Carroll County, the MS4 permit regulates discharges into, through, and from the storm drain system owned by the County or any of the eight incorporated municipalities. The Carroll County MS4 Permit is held jointly by the County and municipalities and requires us to have certain programs that control, monitor, and reduce pollutants within our boundaries.
"Why is the County rebuilding or changing the stormwater pond in my neighborhood?"
As part of the County’s MS4 permit, we are required to reduce the pollutants that enter our waterways. Stormwater ponds and other stormwater management structures provide several important functions, including flooding prevention, protecting downstream waterways from erosion, and filtering pollutants from stormwater runoff. If you see a stormwater pond being rebuilt, it may be getting an upgrade as part of our restoration program to enhance its water-cleaning capabilities!
"What are the white PVC tubes in my yard? Why did someone from the County just inspect them?"
The white PVC tubes or caps that you see in your yard may be part of a dry well. Dry wells are one type of small-scale stormwater management structure that captures runoff from your gutters and allows it to soak into the ground. This helps replenish groundwater and reduce surface runoff. All stormwater facilities, no matter how big or how small, are required to be inspected every three years. Inspectors from the Bureau of Resource Management make sure that everything is connected and functioning properly during their assessment.
"What should I do if I observe pollutants in the storm drain or waterway?"
We always advise people to call 911 or Hazmat right away if there is an emergency or hazardous situation. For non-emergency situations, please call the Stormwater Pollution Hotline at 410-386-2210 to report your concerns. The hotline is managed by the Bureau of Resource Management. Please note that we are unable to process anonymous complaints.