The task seemed impossible. Construct an entirely new Powder Activated Carbon water treatment system at the Sunol Valley Water Treatment Plant that must be ready for service by the January 2019 Hetch Hetchy shutdown, while the Plant remained in operation.

Why the rush? The SFPUC’s 2.7 million Bay Area customers would rely solely on local watershed sources for their drinking water for 60 days during this shutdown. Powder Activated Carbon, or PAC, is a powerful tool to combat the taste and odor effects of blue-green algae blooms in a water supply. These blooms have become increasingly common in the SFPUC’s East Bay Reservoirs. And these East Bay Reservoirs become one of the SFPUC’s primary sources of water supply during Hetch Hetchy shutdowns. Hence, the hurry.

It became clear to the operators of the Sunol Valley Water Treatment Plant, the water quality engineers monitoring the system, and the construction team building the PAC system that proactive communication and coordination would be crucial. During construction, Chief Stationary Engineer Tony Scott, Water Quality Engineer Daniel Kim, Project Construction Manager John Wen, and Regional Project Manager Susan Hou became near constant companions, along with the design team – Stantec, and the construction contractor – Anvil. 

“It became a joke that my secondary office was Tony’s office,” said Project Construction Manager John Wen.

By working closely with one another, the construction team and the operating crews were able to address the inevitable schedule conflicts that come up during a tight construction schedule. There were times when the plant had to be in service when the construction scheduled called for it to be out of service.

“The contractor had their timeline. We had to do what we needed to do from an operational standpoint,” notes Chief Stationary Engineer Tony Scott. “Looking back on that, we were able to work it out.”

The entire team often worked collectively to meet crucial milestones. For example, due to a procurement issue, Water Quality Staff, the construction contractor, and the Water Treatment Plant operators had to monitor the PAC system in manual operation around the clock for several days to pass a crucial reliability test prior to the shutdown.

“Overcoming a particular challenge to meet project schedule, being cooperative and working together, and coming up with both a solution and execution is actually very unique,” notes Water Quality Engineer Daniel Kim. “This shows how unique this particular team was in working together.”

Regional Project Manager Susan Hou concluded, “The teamwork made a huge difference in the dynamics here. We even won a 2019 San Francisco Collaborative Partnering Award because we worked so well together.”

The system was brought online in December 2019, right on time for the Hetchy shutdown.

Fortunately, operators did not encounter any issues during the shutdown, so they did not need to deploy the PAC. But the system had to be, and continues to be, ready in case the SFPUC needs it.