Dec 04, 2018

Smart Diversion System Reduces Potable Water Use

Storm water diversion system manages water use in California

For the drought-stricken city of Lakewood, Calif., in Los Angeles County, implementing a smart regional storm water best management practice (BMP) was necessary to not only meet state permit regulations for the Los Cerritos Watershed Management Plan, but also to reduce potable water consumption. The Bolivar Park Storm Water Management Project uses an air-inflated rubber dam diversion system to redirect urban storm water runoff from the Del Amo Channel through a pre-treatment system that removes trash, debris and sediment. A pump station and drainage pipe then convey the water into a buried multi-chambered storage and infiltration facility. The treated runoff is used to irrigate Boliver Park’s landscaped areas.

“Being a part of the first large regional project that provides multiple benefits from potable water reduction, pollutant load reduction and increased flood capacity in the channel [is a point of pride],” said Jeremy Hohnbaum, project manager with Tetra Tech, the designer firm for the project.

The project also uses smart, real-time controls to optimize system performance and monitor weather conditions through a cloud-based system. The system automatically controls water levels to maximize irrigation storage between storms and maximize capture capacity prior to impending runoff.

“It was critical in meeting water quality objectives and permit compliance to help avoid heavy penalties that would have been assessed to the local agencies,” Hohnbaum said. “It also sets precedence for other on-site treatment and reuse projects.”

While the project spearheads on-site treatment and reuse projects in the region, getting appropriate permits and overcoming design issues were challenges during design and construction. Funding from the California Department of Transportation (Caltrans) required the city of Lakewood to meet an accelerated schedule in order to secure a design firm, complete necessary permits and being construction in less than two years. Obtaining appropriate approvals and permits from governing agencies such as the local county health department and flood control districts was a challenge on the accelerated timeline.

Additionally, the proposed diversion is located 600-ft from the proposed subsurface storage structure and high groundwater levels limited the depth of the subsurface structure. To navigate this design issue, a pump station was constructed, enabling storm water runoff to be conveyed to the storage structure. Many parties collaborated to make the Bolivar Park project possible.

“[The] city of Lakewood and the County of Los Angeles worked together to get the project kicked off,” Hohnbaum said. “Caltrans funded the entire project which was critical.”

Project Year:
Contractor: Reyes Construction Inc.
Designers: Tetra Tech Inc.
Solution Providers: StormTrap, Obermeyer, Bio-Clean, Wahaso, OptiRTC
Owner: City of Lakewood, Calif.
Location: Lakewood, Calif.
Cost: $11 million
Size: 381.614 cu ft