Phase II NPDES Permit – Is Your MS4 Program Meeting its Milestones?

Ohio EPA’s deadline to update your comprehensive stormwater management code, erosion & sediment control code, and Stormwater Management Program (SWMP) is fast approaching.

CRWP is here to help.

We developed model codes and a SWMP template to assist our members with the updates. (See the links under the Resources section of this page.)  Updated SWMPs must be submitted to Ohio EPA for review within 2 years of the permittee’s MS4 permit renewal date.

If you have any questions about the program, please contact us at (440) 975-3870 or



Stormwater discharges are generated by runoff from land and impervious areas such as paved streets, parking lots, and building rooftops during rainfall and snow events that often contain pollutants in quantities that could adversely affect water quality. Most stormwater discharges are considered point sources and require coverage by a National Pollutant Discharge Elimination System (NPDES) permit. The primary method to control stormwater discharges is through the use of best management practices.


Under the NPDES General Permit for Small Municipal Separate Storm Sewer Systems (MS4), some Chagrin River watershed communities are required to submit Phase II stormwater management programs to the Ohio Environmental Protection Agency to detail how each individual community will comply with the Phase II mandates. These regulations require designated communities to develop and implement a stormwater management plan. This program is composed of six minimum control measures:

  1. Public Education
  2. Public Involvement
  3. Illicit Discharge Detection and Elimination
  4. Construction Site Runoff Control
  5. Post Construction Site Runoff Control
  6. Good Housekeeping