Stormwater Non Point Discharge System (NPDES) in Richland County
In addition to requirements Richland County landowners follow for earthmoving activities through the Richland County Stormwater and Erosion Control Program, communities that have 1000 or more people per square mile must follow the Stormwater Non Point Discharge System (National Pollutant Discharge Elimination System) (NPDES) General Permit for Small Municipal Separate Storm Sewer Systems (MS4) to further effectively manage water pollution. The Richland County Commissioners are mandated by Ohio EPA to create and manage this added accountability for stormwater runoff. The NPDES (MS4) communities in Richland County are: City of Mansfield, City of Ontario, Village of Lexington, Madison Township, Mifflin Township, Springfield Township and Washington Township.
Stormwater runoff is generated when rain and snowmelt events flows over land or impervious surfaces and does not percolate into the ground. As the runoff flows over the land or impervious surfaces (paved streets, parking lots, and building rooftops), it accumulates debris, chemicals, sediment or other pollutants that could adversely affect water quality if the runoff is discharged untreated. The primary method to control stormwater discharges is the use of best management practices (BMPs). In addition, most stormwater discharges are considered point sources and require coverage under an NPDES/MS4 permit.
Water pollution degrades surface waters making them unsafe for drinking, fishing, swimming, and other activities. Authorized by the Clean Water Act, the National Pollutant Discharge Elimination System (NPDES) permit program for MS4 controls water pollution by regulating point sources that discharge pollutants into waters of the United States. Point sources are discrete conveyances such as pipes or man-made ditches. Individual homes that are connected to a municipal system, use a septic system, or do not have a surface discharge do not need an NPDES/MS4 permit; however, industrial, municipal, and other facilities must obtain permits if their discharges go directly to surface waters. In most cases, the NPDES/MS4 permit program is administered Ohio EPA. Since its introduction in 1972, the NPDES permit program is responsible for significant improvements to our Nation’s water quality. These regulations require designated communities to develop and implement a storm water management plan. This is accomplished by implementing six minimum control measures.
- Public Education — BMPs for MS4s to inform individuals and households about ways to reduce stormwater pollution.
- Public Involvement — BMPs for MS4s to involve the public in the development, implementation, and review of an MS4’s stormwater management program.
- Illicit Discharge Detection & Elimination — BMPs for identifying and eliminating illicit discharges and spills to storm drain systems. Learn more about how to test for an IDDE.
- Construction — BMPs for MS4s and construction site operators to address stormwater runoff from active construction sites.
- Post-construction — BMPs for MS4s, developers, and property owners to address stormwater runoff after construction activities have completed.
- Pollution Prevention/Good Housekeeping — BMPs for MS4s to address stormwater runoff from their own facilities and activities.
If there is a land disturbance within the NPDES/MS4 area it may require engineered plans. Please contact us as part of your planning process to find out. Our office can provide detailed steps of how a land use change can be made while still complying and how to work with EPA (Environmental Protection Agency) directly.
Richland Soil and Water Conservation District assists communities with a variety of public education, outreach, involvement and participation programs to help meet the requirements of the local MS4 management plan. These programs include electronic newsletters, social media platforms, website updates and workshops.
2026 Stormwater Theme: Only Rain Down the Drain
In the final quarter of 2025, we inspected our MS4 township garage facilities to confirm their good housekeeping practices. We enjoyed catching up with the township road supervisors and discussing our plans for the new permit term, which will run from 2026 to 2030.
2026 brings a new MS4 theme: Only Rain Down the Drain!
Many people don’t realize that, unlike a sanitary sewer, the water that enters a storm drain or ditch is NOT treated. There’s no filtration or disinfection process. Stormwater simply flows (often through a system of pipes, culverts, and catch basins) to the nearest stream, lake, or river. That means anything the water picks up along the way (from litter to oil) is carried into our local waterways. What goes down the drain goes into our environment.
Join us throughout 2026 as we highlight simple ways to protect our waterbodies. If you’re planning a project this year, come get your stormwater permit to ensure you’re only sending rain down the drain. Small choices can make a big impact! Learn more here: https://www.onlyraindownthedrain.com/
Learn more about the MS4 program in Richland County by contacting the MS4 Technician.
We sell rain barrels and have them in stock. You may purchase one online or let us know and we will make arrangements with you to pick one up.