East Bay Municipal Utility District (EBMUD) announced it has completed the installation of the Oakland Inner Harbor Crossing pipeline over the April 7 and 8 weekend. The earthquake-resistant pipeline, which was installed below the Estuary floor, will provide reliable water infrastructure to the City of Alameda.

According to EBMUD, the old pipeline, which was constructed in the 1940s and used cast-iron pipeline, was susceptible to liquefaction during an earthquake and reached the end of its useful life. The new pipe material significantly increases flexibility and durability, improving system reliability during an earthquake.

“The pull of the new pipe under the estuary was a remarkable feat of engineering and construction,” said EBMUD Board Director Doug Linney, who represents EBMUD’s Ward 5, which includes the City of Alameda. “This work will benefit the 76,000 residents of Alameda for decades to come with a more resilient and reliable water distribution pipeline. We are extremely grateful and proud of this effort, the crews who performed it, and our customers for their patience and support.”

Construction crews drilled a bore hole 160 feet beneath the estuary and fused together 63 sections of high-density polyethylene water transmission pipe. The 3,000-foot pipeline, which is 32 inches in diameter, stretched more than half a mile along Mitchell Avenue before it was pulled through the bore hole north of Estuary Park in Oakland. In 2022, EBMUD awarded a $25 million contract to Cratus Inc., a San Francisco-based construction company, to complete the project.

The Oakland Inner Harbor Crossing took nearly a decade to complete. The City of Alameda has four existing pipelines that feed Alameda — the Alice Street-Webster Street crossing, the two northeastern corridor crossings along Park Street, and the Bay Farm Island crossing. At the Oct. 15, 2022 EBMUD meeting, Design Project Manager Raffi Moughamian said because there are no reservoirs of any treated water, "if any one of these pipelines fails at one point in time it can affect the level of service to the Alameda.” EBMUD realized this was an issue and they created the Alameda-North Bay Farm Island Master Plan in 2014. The plan calls for EBMUD to reduce the four water transmission lines that serve Alameda to three transmission lines — the two crossings along Park Street will be reduced to one crossing. In 2016, EBMUD completed an environmental impact report for the full project that prioritized the Alice Street-Webster Street crossing, which is the Oakland Inner Harbor Crossing pipeline.

In the coming months, crews will continue with the installation of two miles of 24-inch steel pipeline to connect the new high-density polyethylene pipe to the EBMUD system in both Oakland and Alameda. To support long-term goals for diverse water supply sources, once the new transmission line is put into service, EBMUD will investigate whether the old crossing can be repurposed to serve as a recycled water line. In addition, work on the second Alameda transmission replacement at Bay Farm Island will begin in five years, and the final crossing parallel to Park Street will occur last.

The project will continue for the next eight months, starting with limited daytime road closures on Sherman Street, and moving block by block toward Marina Village Parkway.