Southeast Water Pollution Control Plant Nutrient Reduction

Project Description

The San Francisco Public Utilities Commission (SFPUC) is issuing this Request for Qualifications (RFQ) in search of Applicants with the specified qualifications to respond to the forthcoming Request for Proposals (RFP) to design and construct the DB-141 Southeast Water Pollution Control Plant Nutrient Reduction project (Project). An “Applicant” is any entity responding to this RFQ.

The Southeast Treatment Plant (SEP) is the centerpiece of SFPUC’s wastewater treatment operations. Built in 1952, SEP is San Francisco's largest wastewater facility with a treatment capacity rated for 85.4 MGD designed average dry weather flow (ADWF) and 250 MGD of designed peak wet weather flow (PWWF). The SEP is the main treatment plant for the city, handling about 80% of the wastewater and stormwater from the eastern two-thirds of San Francisco. Treated effluent in dry weather from the SEP is discharged via the Pier 80 Outfall into Lower San Francisco Bay under National Pollutant Discharge Elimination System (NPDES) No. CA0037664. In wet weather secondary treated effluent from the SEP is discharged to Quint Street Outfall up to 140 million gallons per day (MGD) and primary treated effluent up to 110 MGD from SEP is discharged to Pier 80 Outfall.

In July 2024, the San Francisco Bay Regional Water Quality Control Board (RWQCB) adopted the Nutrient Watershed Permit (Watershed Permit) (CA0038873) that reduces the amount of nutrients, specifically total inorganic nitrogen, discharged from the Southeast Treatment Plan (SEP) into San Francisco Bay. The permit includes two effluent limits on the average seasonal discharges from the SEP that occur between May 1 and September 30: (1) “Interim” limit effective upon permit adoption of 11,000 kilograms (kg) of total inorganic nitrogen (TIN) as nitrogen (N) per day; and (2) “Final” limit effective October 1, 2034 of 3,300 kg-N/day as SFPUC’s current allocation in a Bay-wide load limit allocated to the 37 dischargers. The “final” effluent limits will only be effective if the Bayside Aggregate Mass Load Limit of 26,700 kg-N/day is exceeded.

To address the Watershed Permit requirements, SFPUC is embarking on the Nutrient Reduction Project (Project). Based on a preliminary conceptual evaluation, the proposed Project assumes maximization of the use of existing infrastructure to reduce costs. This baseline concept for the Project has an escalated, total project cost of $1,470,000,000 and is included in the 10-year capital planning process. It assumes a scope of work comprising:

• Retrofit and/or replacement of the existing high-purity oxygen (HPO) activated sludge system to produce densified activated sludge;
• Construction of a new biological nutrient removal (BNR) system; and
• Modification of existing aeration basins (Facility 200).
This baseline concept is subject to an alternative analysis that will select a variant and configuration of nutrient treatment that achieves maximum return on investments and benefits to SFPUC stakeholders. Specifically, the selected nutrient treatment strategy must:
• Reliably meet or exceed the environmental and permitting compliance requirements in the Watershed Permit;
• Be constructable within the existing SEP site without disrupting ongoing plant operations and maintenance (O&M); and
• Have attained technology maturity and demonstrated successful operation at similar facilities.

The size, scale and complexities of the Project represents a significant effort to deliver in the timeframe required. Following a series of consensus-building workshops with key stakeholders, it was determined that PDB represents the most advantageous method for delivering the Project to achieve the following objectives most desired by key stakeholders:

• Maintaining operational continuity;
• Optimizing lifecycle cost;
• Enabling flexibility in design changes;
• Maximizing innovation and value engineering;
• Facilitating early environmental review and risk mitigation;
• Achieving early cost and schedule certainty; and
• Allowing early contractor involvement.

The SFPUC strongly encourages all Applicants to attend the RFQ Pre-Submittal Conference on March 31, 2025 at 10:00am.

https://sfwater.zoom.us/j/88349303573?pwd=aUzfDmRwUAbBvalsbVNxD0WfTlfybF.1

All requests for information concerning the RFQ must be directed to qbd@sfwater.org no later than the Deadline for Applicants to Submit RFQ Questions.