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Illicit Discharge Detection and Elimination
An illicit discharge is any discharge to a municipal separate storm sewer system (MS4) that is not composed entirely of stormwater, except for discharges allowed under an NPDES permit or waters used for firefighting operations.
Detection Program
Methods and procedures for identifying illicit discharges in stormwater systems.
System Mapping
- Outfall inventory and mapping
- Storm sewer system documentation
- Land use and high-risk area identification
- Digital mapping system maintenance
Field Screening
- Dry weather outfall screening
- Water quality testing
- Visual inspections
- Flow monitoring
Elimination Procedures
Steps for removing and preventing illicit discharges once detected.
Investigation
- Source tracking procedures
- Dye testing protocols
- Video inspection methods
- Smoke testing procedures
Enforcement
- Legal authority implementation
- Compliance notifications
- Enforcement escalation procedures
- Follow-up inspections
Prevention Measures
Proactive steps to prevent future illicit discharges.
Business Education
- Industry-specific guidance
- Best practices training
- Spill prevention education
- Proper disposal methods
System Maintenance
- Regular system inspections
- Preventive maintenance
- Record keeping procedures
- Staff training programs
Program Success Metrics
- Number of illicit discharges detected and eliminated
- Percentage of outfalls screened annually
- Response time to reported incidents
- Number of enforcement actions taken
- Reduction in water quality violations