Moccasin Powerhouse Bypass Upgrade

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 construct the HH-1018 Moccasin Powerhouse Bypass Upgrade project (Project). An “Applicant” is any entity responding to this RFQ. Water deliveries for the San Francisco Public Utilities Commission (SFPUC) originate at Hetch Hetchy Reservoir and travel through Early Intake Dam to the beginning of the Mountain Tunnel, which extends more than 18 miles. After passing through the Mountain Tunnel, water enters Priest Reservoir and continues through the Moccasin Power Tunnel to the Moccasin Penstocks. At the West Portal Valve House, located at an elevation of 2,116 feet above mean sea level (MSL), water enters the Moccasin Penstocks and descends approximately 1,200 feet to the Moccasin Powerhouse (MPH). At MPH, water passes through two hydroelectric turbines where the energy of high-pressure water is converted into electricity. When electricity generation is not required or turbine/generator units are down for repairs or maintenance, water is diverted around the turbines through two existing bypass valves capable of dissipating up to 143,000 horsepower of hydraulic energy. The bypass system can convey up to 305 million gallons per day (mgd) at pressures of approximately 560 pounds per square inch (psi). After passing through MPH, water enters either Moccasin Reservoir or the Moccasin Reservoir Bypass Pipeline before continuing through the Foothill Tunnel to the San Joaquin Pipelines (SJPLs) and ultimately serving customers throughout the San Francisco Bay Area. Historically, periodic short-term operation of the bypass system has resulted in significant vibration and cavitation damage to the high-pressure energy-dissipating valves. Extended operation of the bypass valves (greater than two to five days) could lead to severe mechanical damage or valve failure, potentially interrupting critical water deliveries to San Francisco. The objective of the MPH Bypass Upgrades Project is to upgrade or replace the high-pressure energy-dissipating valves, control systems, and associated structures to provide a reliable hydraulic bypass system around the turbines and directly to the Moccasin Reservoir Bypass Pipeline. These improvements will enhance the operational flexibility of Hetch Hetchy Water & Power (HHWP), enabling continued delivery of scheduled water supplies during outages or curtailments affecting the Moccasin Powerhouse, Moccasin Switchyard, or Transmission Lines 3 and 4. The SFPUC strongly encourages all Applicants to attend the RFQ Pre-Submittal Conference on Tuesday, September 29th 2026, at 10:00 AM. https://sfwater.zoom.us/j/81482595732?pwd=DIaK1T8PawrEZvnMmYiILPpSlD3Wvd.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.