Wastewater Treatment


RMC’s planning and design professionals understand complex wastewater treatment and permitting issues and identify project alternatives that provide the greatest increase in reliability within available project funding.

3D rendering of SMCSD treatment plant

Treatment and Wet Weather Flow Upgrade Final Design

Sausalito-Marin City Sanitary District

RMC is providing a suite of design services for Sausalito-Marin City Sanitary District’s Wastewater Treatment Plant, located on a highly constrained site on the San Francisco Bay leased from the National Park Service. We designed a new headworks facility, washer/compactors, pumps, grit washer, hydraulic vortex grit removal system, dewatered sludge handling system, primary clarifier, fixed film reactor upgrades, tertiary filtration, and roadway improvements to allow trucks easy access for sludge removal. RMC worked with the district to accommodate maximum flexibility in meeting long-term changes that may occur to the secondary treatment and during peak wet weather flow. The project improves trickling filter capacity—including media replacement and odor control covers—provides 0.6 MG of equalization storage, and replaces secondary polishing (filtration with disc filters). RMC assisted in obtaining project approval from the National Park Service and with the amendment to the existing San Francisco Bay Conservation and Development Commission permit.

Clarifier at Brentwood Treatment Plant

Wastewater Treatment Plant Expansion Phase 2

City of Brentwood

The RMC team is providing preliminary design, final design, and bidding and construction support services to expand the capacity of the City of Brentwood’s wastewater treatment plant from 5.0 MGD to 7.5 MGD, and eventually to 10.0 MGD. The goal of this phase of the project is to meet the Brentwood’s near-term needs, while optimizing new facilities to meet long-term goals and making the facility as energy efficient as practical. Services consist of recalibrating buildout flows and load criteria based on newer data and the city’s population projections; reassessing current and future required process capacity based on revised flow and load projection; transitioning to diffused air for process flexibility, increased capacity, and energy efficiency; re-rating the existing filters to eliminate the need for additional units; and providing direction for disinfection and biosolids dryer process upgrades.

IEUA RP-1 treatment plant aerial

RP-1 Mixed Liquor Return Pumps

Inland Empire Utilities Agency

RMC designed a Mixed Liquor Return Pumps system at Regional Water Recycling Plant No. 1 (RP-1) to reduce effluent Total Inorganic Nitrogen (TIN) to comply with NPDES and groundwater recharge program permit conditions. Our team had originally completed and alternatives evaluation and final design nearly a decade ago, but the project was shelved before construction. For the current project, we revisited the assumptions, confirmed the solution, and provided revised design documents. The revived project was completed on a fast-track schedule to allow construction completion by June 2017 to meet summertime recycled water demand.

Construction along Alvarado Street

Alvarado Wastewater Treatment Plant Site Use Study

Union Sanitary District

RMC is developing a Site Use Study to identify land area needs and optimize the plant site to meet future operational and maintenance needs for USD’s Alvarado Wastewater Treatment Plant. We are determining the best configuration of process, maintenance, storage, and green energy facilities; considering space needs, required connections, truck access, aesthetics, cost, and impacts to neighbors. RMC is also investigating space-saving alternatives, including re-purposing of existing structures and evaluation of alternative, space-efficient process technologies and train configurations. We held workshops during key points in the site use study to include staff from operations and maintenance teams to gather input on priorities and to build consensus on how best to meet those priorities.

Malibu coastline

Civic Center Wastewater Treatment Plant

City of Malibu

RMC is designing a centralized wastewater collection and treatment system and recycled water distribution system for the City of Malibu in response to several regulatory orders that will ultimately ban the use of onsite wastewater treatment systems in the Civic Center Area. Groundwater injection was identified as a secondary means for effluent disposal. RMC prepared a Report of Waste Discharge (ROWD) for submittal to the Los Angeles Regional Water Quality Control Board (RWQCB) and coordinated with the City, RWQCB, and California Department of Public Health (CDPH) throughout the process. RMC prepared a Title 22 Engineering Report for submittal to CDPH, prepared the permit application for the Coastal Development Permit through the California Coastal Commission, and assisted with encroachment, building, and grading permit acquisition. RMC and its subconsultant prepared a project-level environmental impact report (EIR) for the Malibu Wastewater Treatment Plant, associated collection and recycled water facilities, and percolation/injection facilities.