MWH Constructors and its joint venture partner Webcor Builders have secured a $939m construction manager/general contractor (CM/GC) contract from the San Francisco Public Utilities Commission (SFPUC) for the Southeast Water Pollution Control Plant (SEP) Biosolids Digester Facilities Project (BDFP).

Constructed in 1952, SEP purifies 80% of sewage and storm water in San Francisco.

The BDFP aims to enhance energy recovery and increase odor control by substituting the current digester facilities with new, expanded, reliable, modernized and relocated facilities.

Using the Cambi thermal hydrolysis process, the BDFP will enable the new facilities to produce quality biosolids, capture and treat odors effectively

The construction of the plant will commence in the summer of 2018 and it will be commissioned in summer 2025.

The facility will be built in two phases, where destruction and site preparation of SEP and the current asphalt plant will be processed in the first phase. The second phase includes the demolition of the central shops and construction of the BDFP.

SFPUC offers water services to over 2.6 million residential, commercial and industrial customers.

MWH Constructors president Blair Lavoie said: “Our partnership with Webcor Builders combines unique and relevant experience in water and wastewater facilities and integrates the complementary expertise and resources of two leading general contractors to provide the highest quality service and best partner for the sustainable development of San Francisco’s water infrastructure and community.”

Established in 1993, MWH Constructors is a project delivery firm that aims at water and energy, and provides single-source construction services.