Stormwater Case Studies Search Results
Case Study Location: California: Santa Monica
Case Study Title: Urban Runoff BMPs for Municipal Facilities
Minimum Control Measure: Pollution prevention/good housekeeping for municipal operations
Location: California: Santa Monica
The City of Santa Monica's Environmental Programs Division has taken a proactive approach to preventing and treating urban runoff discharges from municipal activities and other sources throughout the community. The City has invested heavily in facilities to wash municipal vehicles, treat dry-weather flows, and install innovative runoff reduction practices at municipal sites. The City also has conducted urban runoff training sessions for municipal crews.
Bus Wash Facility
The city-owned and operated Big Blue Bus system built a new bus wash center with a water reclamation system that will cut water use by up to 50 percent and reduce the likelihood of non-stormwater discharges. Wash water is captured, filtered and reused, ensuring that runoff from the bus wash center does not enter receiving waters. Stormwater runoff from this facility and the surrounding parking lot drains into two large sub-surface infiltration basins, removing stormwater pollutants and recharging ground water.
Training of Municipal Crews
The city's Urban Runoff Coordinator continues to conduct urban runoff training sessions for city field crews at city yards, the airport, and all other city facilities. Approximately 150 employees receive annual training on the City's urban runoff ordinance, NPDES permit, urban runoff concerns, and best management practices (BMPs) related to city operations. The employees, in turn, provided feedback on how to improve urban runoff management at their job sites. The employees' recommendations for procedural and structural changes resulted in significant improvements to the city's storm water pollution prevention plans (SWPPPs).
Urban Runoff Recycling Facility
The city owns and operates an urban runoff recycling facility, called the Santa Monica Urban Runoff Recycling Facility (SMURRF) , which treats an average of 350,000 gallons per day of dry-weather urban runoff for reuse in Santa Monica. Approximately 50% of the dry weather flows originate in the City of Los Angeles, which is an equal partner in this project. Dry weather runoff water generated from activities such as over-irrigation and residential car washing is diverted from the city's two main storm drains to the SMURRF. During rain events, SMURRF is inoperable and stormwater runoff is discharged to Santa Monica Bay. This is because it would not have been economically feasible to design the SMURRF to treat the extremely high volume of stormwater generated during rain events. Treatment processes at the SMURRF include coarse and fine screening to remove trash and debris, degritting systems to remove sand and grit, dissolved air flotation to remove oil and grease, microfiltration to remove turbidity, and ultraviolet radiation to kill pathogens. Once treated, the water is safe for all reclaimed water applications, such as landscape irrigation and dual-plumbed indoor systems, as prescribed by the California Department of Health Services.
Low Impact and Runoff Treatment Practices
The city has installed permeable pavement in lightly used areas such as alleys and parking lots and has used permeable pavement as porous gutters for many residential streets, providing additional runoff treatment through infiltration of stormwater runoff. Infiltration pits, porous concrete, bioswales, and French drains were also installed on City property to reduce runoff. Additional Runoff treatment practices installed by the city include catch basin inserts and screens, a StormTreat' system, multi-stage BMP systems, a multipurpose 'green' beach parking lot, and diversions. Soluble filtration systems will soon be installed at various locations.
Additional Materials Related to this Case Study:
EPA presents this case study as an example to which Phase I and Phase II municipal stormwater programs can refer as they develop their own stormwater programs. Although EPA has reviewed the case studies, they should not be considered officially endorsed by the Agency and are not intended to represent full compliance with EPA’s stormwater Phase II minimum control measures. Each community must decide on the appropriate BMPs necessary to meet its unique permit requirements and local conditions.