City & County of San Francisco Public Utilities Commission


Richard Graham, City and County of San Francisco Public Works


The Mariposa Pump Station (MPS) Improvements Project included removing the existing pump station and constructing a new pump station at the same location to accommodate full buildout of the Mission Bay, including the new Warriors Arena and other nearby communities including Dogpatch and the Potrero Hill neighborhoods. These facilities are a critical component of San Francisco’s wastewater operations and provide reliable, high-quality service to all who live, work and play in San Francisco.


This project included a large amount of new infrastructure within a small postage stamp piece of real estate tucked next to the SF Marina. This required the use of engineered frozen soil systems to cut off groundwater and provide temporary shoring for the 40’ deep excavation next to the Bay allowing for the concrete construction and CLSM backfill.


This project provides the SFPUC the ability to maintain critical sewer system services by increasing the existing dry weather capacity of the MPS while at the same time meeting San Francisco seismic standards and sea level rise requirements. The MPS will increase sewer system reliability and protect water quality and aquatic life in the Bay