NPDES Municipal Regional Permit

National Pollutant Discharge Elimination System Permit

All cities must comply with a National Pollutant Discharge Elimination System (NPDES) Permit to discharge stormwater to the storm sewer system. The permit controls water pollution by regulating sources that potentially discharge pollutants to waterways.

In June 1990, member agencies received the first NPDES municipal stormwater permit in the nation from the San Francisco Bay Regional Water Quality Control Board (Water Board). The permit was reissued in 1995, 2001, 2009, and 2015. The permit reissued in 2009 and 2015 is referred to as the Municipal Regional Permit (MRP). Negotiations are currently underway for the next MRP with an effective date anticipated to be July 1, 2022. The MRP covers stormwater discharges from a total of 76 municipalities and local agencies in Alameda, Contra Costa, San Mateo, and Santa Clara Counties, and the cities of Fairfield, Suisun City, and Vallejo. Some of the most challenging stormwater management requirements in the current MRP include:

OkMRP Requirements

The Authority's member agencies must comply with the NPDES stormwater permit, which mandates certain activities. The Authority develops an annual work plan to fulfill the requirements of the MRP and to reduce the amount of pollutants discharged in urban runoff. The plan is a comprehensive program that is designed to reduce the discharge of pollutants to the maximum extent practicable and encompasses best practices for the following operational areas:

C.2 Municipal OperationsC.2 Municipal Operations
Street sweeping, road maintenance, and corporation yard activities.

C.3 New Development & RedevelopmentC.3 New Development & Redevelopment
Implementing green stormwater infrastructure features into private and public projects. These features allow stormwater runoff to soak into the ground and be filtered by soil.

C.4 Industrial & Commercial Site Controls

C.4 Industrial & Commercial Site Controls
Educating business owners and inspecting over 350 industrial and commercial sites a year or annually.

C.5 Illicit Discharge Detection & Elimination (IDDE)

C.5 Illicit Discharge Detection & Elimination (IDDE)
Maintaining a system for receiving complaints of illegal discharges to storm drains; responding and investigating reports.

C.6 Construction Site Controls

C.6 Construction Site Controls
Educating property owners and developers and inspecting construction sites to ensure they are implementing practices to prevent stormwater pollution.

C.7 Public Information & OutreachC.7 Public Information & Outreach
Educating and engaging the community through social media, public events, and classroom presentations.

C.8 Water Quality Monitoring

C.8 Water Quality Monitoring
Assessing local creek health and identifying sources of impacts.

C.9 Pesticides Toxicity Controls

C.9 Pesticides Toxicity Controls
Managing municipal facilities and parks with least toxic chemicals and educating the community on alternatives to pesticides for controlling common home and garden pests.

C.10 Trash Load Reductions

C.10 Trash Load Reductions
Installing trash capture devices in storm drains, conducting creek and homelessness camp cleanups, and banning single-use products, like plastic bags and styrofoam.

C.11 Mercury Controls

C.11 Mercury Controls
Controlling discharges of mercury (thermometers and fluorescent light bulbs).

C.12 Polychlorinated Biphenyls (PCBs) Controls

C.12 Polychlorinated Biphenyls (PCBs) Controls
Controlling discharges of polychlorinated biphenyl (PCB) (demolition of old buildings).

C.13 Copper Controls

C.13 Copper Controls
Controlling discharges of copper (ornamental features and pool/spa discharge).

C.15 Exempted & Conditionally Exempted Discharges

C.15 Exempted & Conditionally Exempted Discharges
Defines discharges that may enter a storm drain or may conditionally enter a storm drain if certain conditions are met.