The $283 million seismic and reliability upgrades project at the Harry Tracy Water Treatment Plant in San Bruno is more than 65 percent finished.
The plant has been off-line for two months as workers on two shifts performed intensive work in multiple locations, including on the water pipeline located underground along the hillside behind Meadows School in Millbrae.
A new steel pipe was placed inside the existing pipeline that carries drinking water from the Plant to the Peninsula.
The plant is expected to come back online this month.
The entire project is expected to be complete in early 2015.
The Treatment Plant is part of the Hetch Hetchy System.