Stormwater Regulations
Phase II Stormwater Regulations
In 1999 the EPA established the Phase II regulations to reduce the impact of pollution that was being created with the increase of development. The NPDES Phase II requires permit coverage for stormwater discharges from small MS4s in urbanized areas and construction activity that disturbing between one – five acres of land. The Environmental Protection Agency defines Urbanized Areas as “ a land area comprising one or more places, central place(s), and the adjacent densely settled surrounding area, urban fringe, that together have a residential population of at least 50,000 and an overall population density of at least 1,000 people per square mile.” The six minimum control measures required by Phase II are detailed below.
What is an MS4?
MS4 stands for “Municipal Separate Storm Sewer System.” An MS4 is a drainage system (including roads, catch basins, curbs, gutters, parking lots, ditches, conduits, pumping devices, man-made channels, etc.) that is designated or used for collecting and conveying storm water which is regulated. During wet weather, pollutants can be transported through MS4s to local water bodies.
Six Minimum Control Measures
Develop, implement and provide program opportunities for active involvement in water quality stewardship.
1. Public Education Program
- Work to inform the public about the steps they can take to reduce/prevent storm water pollution. These steps can include landscape practices, water conservation, proper hazardous waste disposal, and septic system maintenance. Additional information available regarding these practices are available through the Huron River Watershed Council Website.
- View Livingston County’s Public Education Program (PEP)
2. Public Involvement and Participation
- Promoting public involvement in the stormwater management program, such as volunteer stream cleanups or reporting illicit discharges is a requirement. The most recent Public Participation Plan was submitted to the State of Michigan for review in March 2024. However, this plan has not yet been approved. Public viewing of the 2024 Public Participation Plan can found using the following link. Comments regarding the Public Participation Plan can be made to Mitch Dempsey at the Livingston County Drain Commissioner’s Office.
- View Public Participation Plan (PPP)
3. Illicit Discharge Elimination Program
- Storm drain mapping
- Regulations that prohibit non-storm water discharges to MS4’s
- Programs to identify and eliminate illicit discharges and illegal dumping
- Dry weather screening
4. Construction Storm Water Runoff Control
- The Livingston County Drain Commissioner’s Office is the designated Part 91 County Enforcing Agency (CEA) for Livingston County. (View additional information regarding construction storm water runoff control.) This includes general soil erosion control information, County ordinance, and other permitting requirements.
- Resident complaints and inquires facilitate better effectiveness of the County Soil Erosion program.
- Part 91 and the Livingston County Soil Erosion and Sedimentation Control Ordinance help protect storm sewers and waters of the State from sediments.
5. Post-construction Storm Water Runoff Control
- Implement regulatory programs to ensure installation of structural and non-structural BMPs for new development and redevelopment.
- The Livingston County Drain Commissioner’s office has implemented Post-Construction Storm Water Runoff Control standards which have been reviewed by the State of Michigan. These standards are in effect for new development and re-development projects which are 1.0 acres or larger. Many municipalities within Livingston County reference and have adopted these drainage standards as part of their review process for developments. View stormwater standards for Post-construction Storm Water Runoff Control. Ensure long-term operation and maintenance.
6. Pollution Prevention and Good Housekeeping
- Develop and implement programs to prevent and reduce storm water pollution from municipal operations
Livingston County has implemented practices which help reduce storm water pollution from it’s municipal operations. These include inspections, fleet maintenance, cleaning of parking lots and drains, proper contractor use and disposal of fertilizer, pesticide, and herbicide.
