Municipal Separate Storm Sewer

This page contains information relating to Municipal Separate Storm Sewer Systems (MS4)

Recent federal regulations require that storm water discharges from certain small MS4s be covered under a storm water permit.  At this time in Wyoming municipal, county, and other publicly-operated MS4s within the state's two Census Bureau-defined urbanized areas (see maps below) will be required to be covered under a general storm water permit.

  • Beginning July 1, 2013 payment of permit fees for individual permits and general permit authorizations are required to be submitted with the permit application or NOI form.  All storm water authorizations have variable fees that must be calculated depending upon the NOI date.  The "Fee Calculator" should be used to determine the proper amount to be submitted with each NOI.  Checks should be made out to the "Dept. of Environmental Quality, Water Quality Division.