The San Francisco Public Utilities Commission Biosolids Digester Facilities Project is a major modernization of San Francisco’s Southeast Treatment Plant, the City’s largest wastewater treatment facility and the plant responsible for treating approximately 80% of San Francisco’s combined sewage and stormwater flows. The multi-billion-dollar infrastructure project is replacing aging solids-treatment facilities with modern systems designed to produce higher-quality biosolids, improve odor control, increase reliability, and maximize beneficial use of biogas. The project is part of a broader transformation of the Southeast Treatment Plant into a modern resource recovery facility serving San Francisco for decades to come.

CMI is providing mechanical and HVAC expertise for the project, including work associated with the facility’s specialized odor-control infrastructure. The scope includes large-diameter ductwork and mechanical systems supporting the collection and treatment of foul air across multiple facilities. Extensive coordination and heavy installation planning are required to integrate these systems within the project’s complex concrete, structural, process, and mechanical infrastructure while construction progresses within an operating wastewater treatment plant.