The MS4 permit for Genesee County is being administered by the Genesee County Drain Commissioner Surface Water Management Division.
Permit
The current NPDES MS4 permit is available here.
Permit Application
Inventory of applicant-owned or operated facilities and stormwater structural controls with a discharge of stormwater to surface waters of the state (Table 3 of the permit application).
County Facilities
Nested Jurisdictions - Schools