EBMUD Completes Oakland Inner Harbor HDD Crossing
The East Bay Municipal Utility District (EBMUD) has successfully completed the installation of approximately 3,000 ft of 32-in. diameter earthquake-resistant pipeline below the Oakland Estuary floor via horizontal directional drilling (HDD).
The new pipe, serving the City of Alameda, took three months to construct and was installed over the April 7-8 weekend, and replaces a 1940s era cast iron pipeline in an area that is susceptible to liquefaction during an earthquake.
The innovative design, construction and installation of the Oakland Inner Harbor Crossing took nearly a decade of work and partnerships to come to fruition. In 2014, EBMUD completed initial plans to replace the four water transmission lines that serve the City of Alameda with three new transmission lines.
In 2016, EBMUD completed an environmental impact report for the full project and prioritized the first crossing between Alice Street in Oakland to Webster Street in Alameda using HDD to drill a borehole beneath the Oakland Estuary floor near the Posey Tube. In 2022, EBMUD awarded a $25 million contract to Cratus Inc.
Construction crews drilled a bore hole 160 ft beneath the estuary and fused together 63 sections of high-density polyethylene (HDPE) water transmission pipe. This 3,000-ft pipeline stretched more than half a mile along Mitchell Avenue in Alameda before it was pulled through the bore hole north of Estuary Park in Oakland on April 7 and 8. 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 Doug Linney, EBMUD board director 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.”
In the coming months, crews will continue with the installation of two miles of 24-in. steel pipeline to connect the new HDPE 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 approximately five years, and the final crossing parallel to Park Street will occur last.
An Era of Infrastructure Upgrades
EBMUD is entering the most capital-intensive period in its history and is investing more than $2.8 billion in the next five years to rehabilitate water treatment plants, pumping plants, reservoirs, pipelines, wastewater facilities and sewer interceptors.
Aging water and wastewater infrastructure across the EBMUD service area, some of it more than 100 years old, needs continued maintenance and replacement. Water and wastewater systems must deal with earthquakes, climate change, and emerging contaminants, to protect public health and the environment.
“Water infrastructure is the very lifeline of society,” said Jimi Yoloye, engineering and construction director. “We cannot delay investing in this system. We must bring projects like Oakland Inner Harbor Crossing to fruition. The coming years will be exciting and vital for our region’s future.”
EBMUD is a not-for-profit public utility where customer rate dollars directly fund operations and capital improvements. EBMUD is recognized as a responsible financial steward and is the only California water utility to receive Moody’s Investors Service’s highest Aaa water bond rating. As EBMUD innovates to improve infrastructure and services, the utility must also confront rising costs due to supply chain disruptions and inflationary pressures on equipment, chemicals, energy, and labor.
SOURCE – EBMUD