Ripon’s Stormwater Management Program protects water quality in the City’s rivers by regulating stormwater and non-stormwater discharges from commercial and industrial operations as well as other activities.

Stormwater discharges to local rivers from the City’s stormwater conveyance system are regulated under the State’s General Permit for Small Separate Municipal Storm Sewer System (MS4). Under this permit, the City must reduce pollutants in stormwater runoff to the technology-based standard of the Maximum Extent Practicable (MEP). To accomplish this, the City will monitor all discharges from commercial, industrial, construction, residential and municipal activities. Pollutants in stormwater and non-stormwater discharges can be minimized either through source reduction or treatment. Consult the CASQA BMP Guidance Manuals at www.cabmphandbooks.com for more information.

The General Permit effectively prohibits the discharge of materials other than storm water except those that are “authorized” or those permitted by a separate State permit. Through the implementation of best management practices (BMPs), and the use of an iterative process to evaluate their effectiveness, contaminant loads in both stormwater and non-stormwater discharges are reduced. BMPs can be structural or administrative in nature. At this time, BMP selection and implementation is at the discretion of the discharger.

The City’s Stormwater Management Program is implementing a program to reduce pollutants from retail food facilities. Contaminants such as grease, trash and food debris will be targeted.

Discharge of power washing effluent from parking lots, trash enclosures, and floor mat washing to the stormwater system is prohibited. The Stormwater Management Program will respond to reported violations in Ripon. Please contact the Engineering Department at (209) 599-2108 to determine proper disposal options.

BMP fact sheets coming soon

Fact sheets in downloadable PDF files will describe and recommend stormwater BMP's for specific businesses and industries in Ripon.

City Stormwater Ordinance

Under the Illicit Discharge Detection and Elimination section of the State’s General Permit for MS4s, the City is required to effectively prohibit, through ordinance, non-stormwater discharges into the MS4. In addition, the City is required to implement appropriate enforcement procedures and actions to carry out the mandates of the ordinance. The General Permit allows the City to evaluate the following non-stormwater discharges and exempt them from regulation only if they are not significant contributors of pollutants to local waterways. As such, the following discharges, when properly handled, are currently not considered significant contributors of pollutants to the City's stormwater system:

• Water line flushing
• Landscape irrigation
• Diverted stream flows
• Rising ground waters
• Uncontaminated ground water infiltration
• Uncontaminated pumped ground water
• Discharges from potable water sources
• Foundation drains
• Air conditioning condensation
• Irrigation waters
• Springs
• Water from crawl space pumps
• Footing drains
• Lawn watering
• Individual residential car washing
• Flows from riparian habitats and wetlands
• Dechlorinated swimming pool discharges
• Fire fighting flows

Check out the stormwater ordinance (RMC Title 13)