The SFCTA is retrofitting 8 seismically poor bridge constructions on Treasure Island Highway to fulfill present protection requirements. The $126 million challenge, a part of a bigger infrastructure growth program, comes to new maintaining partitions, roadways, and a retrofitted bridge. Finishing touch is anticipated by means of overdue 2026, supporting higher residency, transit get admission to, and financial redevelopment on Yerba Buena and Treasure Islands.
Picture courtesy of the San Francisco County Transportation Authority
Pillings are put in adjoining to the San Francisco Bay.
The San Francisco County Transportation Authority mentioned it’s on time table to finish the $126 million West Aspect Bridges Retrofit challenge on Treasure Island Highway by means of addressing 8 present bridge constructions which might be seismically poor with new maintaining partitions, roadways and a retrofitted bridge to fulfill present protection requirements.
Building started in June 2023 at the constructions, which might be a an important connection between Yerba Buena Island, Treasure Island and the Bay Bridge and will likely be finished by means of overdue 2026.
Picture courtesy of the San Francisco County Transportation Authority
That is one a part of a bigger multimodal infrastructure growth program at the Islands, the opposite two finished being the I-80 East Aspect Ramps Venture (2016) and the Yerba Buena Island/I-80 Southgate Highway and Interchange Venture (2023). The 8 present bridge constructions are at the west facet of Yerba Buena Island and include a viaduct alongside Treasure Island Highway, simply north of the San Francisco-Oakland Bay Bridge (SFOBB).
The challenge prohibit is roughly 2,000 feet. northward towards Macalla Highway. The bridges have been built between 1937 and 1964 and have been made up our minds to be seismically poor so the Transportation Authority, in cooperation with the California Division of Transportation (Caltrans) and the Federal Freeway Management, is operating to carry the bridge constructions, maintaining partitions and roadways as much as present seismic protection requirements.
The challenge is funded the use of federal (Freeway Bridge Program and Rebuilding American Infrastructure with Sustainability and Fairness), Federal Congressionally Directed Spending, state (Proposition 1B) and native (Treasure Island Construction Authority, Bay Space Toll Authority, Native Partnership Program and Proposition Okay Gross sales Tax) price range.
Building is composed of the next seismic retrofit technique, which was once made up our minds to be essentially the most cost-effective manner: demolishing seven bridge constructions, realigning the roadway into the hillside, establishing six maintaining partitions and one undercrossing construction, and seismically retrofitting one bridge construction.
The challenge features a motorcycle trail and can permit for the improvement of a devoted transit-only ramp to the SFOBB, offering higher transit get admission to to the Islands’ citizens.
Picture courtesy of the San Francisco County Transportation Authority
“It is geared for expanding the sturdiness and reliability of the roadways as Treasure Island continues to expand. The plan, from a housing viewpoint, is 8,000 further residential devices,” mentioned Carl Holmes, Transportation Authority’s deputy director of capital initiatives. “We’re operating at the spine infrastructure to toughen and be in a position for the higher residency at the island.”
This challenge will ensure that the resiliency of transportation for Yerba Buena and Treasure Islands and supply unimpeded get admission to to United States Coast Guard Sector amenities for hometown safety. It additionally will fortify roadway protection for drivers, transit customers, pedestrians and cyclists at the island.
And it’s going to toughen the continuing financial redevelopment of Yerba Buena and Treasure Island that can turn into the islands to a colourful new community with 27 p.c of the 8,000 devices Holmes discussed being reasonably priced housing.
The challenge contract supply means is development supervisor/common contractor (CM/GC) with Golden State Bridge/Obayashi JV (GSB/O) selected all through a CM/GC variety procedure in 2018 to supply preconstruction services and products, together with charge estimating, chance research and constructability evaluation. After the finishing touch of the general design in overdue 2022, an agreed value to accomplish development was once made up our minds, and GSB/O was once gotten smaller to build the challenge.
Key subcontractors come with Farwest Protection; Crystal O’Neill Electrical; Get right of entry to Restricted Building; Chrisp Co.; Staff EES; Coral Building Co.; Bay Towns Paving and Grading; West Coast Drilling; Oliveira Fence; Dees-Hennessey; Silverado Contractors; and Gonsalves & Santucci. WSP is offering resident engineering/development control, inspection services and products, development staking and subject matter checking out services and products.
Uniqueness exertions has integrated carpenters, pile drivers/drillers, laborers, ironworkers, running engineers, electricians and Teamsters. Building fabrics come with 6,300 cu. yds. of structural concrete; 2,200,000 lbs. of reinforcing metal; 6,500 linear feet. of metal piling; and 9,600 linear feet. of drilled piling, together with distinctiveness fabrics that comes with 200 cu. yds. of shotcrete; 368 tiebacks/flooring anchors every; and 11,600 linear feet. of soil nails. A number of heavy development apparatus is getting used together with drill rigs, cranes, excavators, loaders, dozers, concrete pumps and vans.
“What the CM/GC contract means did is authorized for us to have interaction with a common contractor whilst we have been finalizing the design. The convenience is we have been ready to raised confirm one of the most dangers that the design won’t have handled in one of the best ways,” Holmes mentioned. “For instance, when it got here to one of the most bridge demolition, having a look at one of the most dangers and ensuring it is accomplished with a undeniable degree of protection, productiveness and velocity. It is been a real collaboration.”
The challenge now calls for the entire closure of Treasure Island Highway till challenge finishing touch in 2026. This permits for a extra environment friendly and shorter development length. To facilitate native visitors, the Transportation Authority coordinated with native construction groups to build the Wooded area Highway Detour, which supplies complete get admission to from Treasure Island to Yerba Buena Island and the eastbound and westbound on ramps to the SFOBB. Upon finishing touch of the challenge, Treasure Island Highway will likely be reopened.
The challenge has witnessed some demanding situations with flooring stipulations when excavating for maintaining partitions, however soil dull exams finished previous within the procedure helped watch for the problem.
Picture courtesy of the San Francisco County Transportation Authority
Building of maintaining partitions and the vehicular field culvert will proceed over the following two years. Holmes additionally shared that native artist Muzae Sesay supplied the design for an ornamental maintaining wall, including a neighborhood arts contact to the challenge.
“We are actively in development at the moment construction maintaining partitions. We finished maximum, if now not all, our bridge demolition. We now have a couple of 3rd of the island roadway closed however we’ve got a detour that has been in position prior to we had the closure so there are methods to nonetheless traverse in the course of the island,” Holmes mentioned.
“It is just right that we have been ready to close down a portion of the roadway as a result of now not having to fret about impacting the general public is useful. An important quantity of labor is being carried out at the steep hillsides of Yerba Buena Island. Get right of entry to constraints and cautious making plans by means of the contractor to expand website get admission to for the apparatus to build, subject matter deliveries and employee protection has been key to a success development to this point.” CEG
Ruksana Hussain
Ruksana Hussain is a Los Angeles, California-based award-winning journalist with 19 years’ revel in operating with native, nationwide and world print and virtual media for client and business markets. As {a magazine} editor and contours author, she covers a vast vary of subjects together with development and design, range and inclusion, knowledge privateness and safety, and extra. She earned her bachelor’s level in sociology in India. Leisurely interests come with touring, random researching and making an attempt phrase puzzles of any nature.
