Fullerton, CA
Home MenuFrequently Asked Stormwater Questions
What is stormwater?
Stormwater is runoff from rain or snowmelt that travels over lawns, rooftops, parking lots, and streets—picking up pollutants like debris, oils, fertilizers, and sediment—which then enter storm drains and flow untreated into local waterways.
What is the NPDES?
The National Pollutant Discharge Elimination System (NPDES) is a federal program under the Clean Water Act that regulates the discharge of pollutants from point sources (e.g., pipes, ditches) into U.S. waters. It requires permits with pollutant limits, monitoring, and reporting.
Who needs an NPDES permit?
Stormwater discharge permits are required for:
- Municipal Separate Storm Sewer Systems (MS4s): Medium and large (Phase I) systems in cities/counties with populations ≥100,000, and small systems in urbanized areas over 50,000 (Phase II).
- Construction sites: Disturbing ≥1 acre or part of a larger development must obtain an NPDES Construction General Permit and implement a Stormwater Pollution Prevention Plan (SWPPP).
- Industrial facilities: Facilities with industrial operations often need NPDES coverage if stormwater contacts industrial materials.
What does an MS4 permit require?
MS4 permittees must develop and implement a Stormwater Management Program (SWMP) that includes:
- Construction site runoff control
- Illicit Discharge Detection & Elimination (IDDE)
- Pollution prevention and good housekeeping
- Post-construction runoff management
- Public education, involvement, and participation
- Program effectiveness assessments
What is an illicit discharge?
An illicit discharge is any non-stormwater discharge to an MS4, such as sanitary sewage, vehicle fluids, or unpermitted industrial wastewater.
What are Best Management Practices (BMPs)?
BMPs are structural, vegetative, or procedural solutions designed to reduce pollutant runoff—such as sediment fences on construction sites, detention basins, or street sweeping programs.
How do I apply for or renew a permit?
Permits are issued by state water boards or EPA regions. General permits involve submitting a Notice of Intent (NOI). Individual permits require detailed applications, public notices, and may take 6+ months to process.
How long are NPDES permits valid?
Typically, NPDES permits last five years and can be renewed. If an application is submitted at least 180 days before expiration and action isn’t taken, the permit is administratively extended.
What happens if we violate permit terms?
Permits require self-monitoring and reporting. Failure to comply can lead to state or EPA inspections, administrative penalties, enforcement orders, civil or criminal actions—and the public can also file citizen enforcement suits.
How does stormwater benefit the community?
Effective stormwater management:
- Protects waterways, wetlands, and ecosystems
- Improves water quality for public health
- Helps control flooding and manage water resources
- Prevents habitat loss and erosion