image showing staff collecting data from surface water
Staff collecting water data

Municipal operation inspections

Municipal operation inspections help reduce the impacts to stormwater from municipally owned or operated facilities, areas, or stormwater best management practices (BMPs). Staff conducting these inspections can stop pollution before it reaches stormwater, or minimize the impacts if your BMPs have failed or need maintenance.

The municipal separate storm sewer system (MS4) General Permit requires inspections of the following: (MS4 General Permit Part III.D.6.e)

  • Annual inspections of structural stormwater BMPs to determine structural integrity, function, and maintenance needs.
  • At least one inspection every permit term of stormwater ponds and outfalls to determine structural integrity, function, and maintenance needs.
  • Quarterly inspections of stockpiles, and storage and material handling areas identified in the Facility Inventory to determine function and maintenance needs.

During each of these inspections, inspectors must look for evidence of illicit discharges (MS4 General Permit Part III.D.3.c.). All inspections must be documented (MS4 General Permit Part III.D.6.h.(1)), so save any checklists that you are using.


Fact sheets and guidance documents

Checklists and templates

BMP inspection checklists

Pond inspection checklists

Outfall inspection checklists