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57/60 Freeway widening

Metro Board Approves $294 Million to Widen 57/60 Freeways Confluence

Metro, Caltrans, and the San Gabriel Valley Council of Governments are widening the 57/60 interchange. 2021 photo by Joe Linton/Streetsblog L.A.

This morning, the Metro board of directors approved $293.6 million for the next and "final" phase of the half-billion dollar 57/60 Freeway widening megaproject [staff report]. Metro's "SR-57/SR-60 Interchange Improvements Project" is located in the east San Gabriel Valley city of Diamond Bar. The freeway expansion is a partnership between Metro, Caltrans, and the San Gabriel Valley Council of Governments (SGVCOG). The SGVCOG is currently managing more than $100 million worth of early construction phases of 57/60 widening, and will oversee the remaining construction approved today.

57/60 project location map - via FHWA
57/60 project location map – via FHWA - click to enlarge
57/60 project location map - via FHWA

The new phase of 57/60 Freeway construction is anticipated to get underway this Spring. Metro’s project page currently forecasts an opening date from 2026-2028.

The 57/60 Freeway widening cost has been a significant factor spurring recent dramatic increases in Metro's annual highway construction budget. In 2021, Metro increased its highway expansion construction program by 80 percent. Then in 2022, Metro increased the highway program by a further 33 percent (at the same as Metro cut transit construction by eight percent). According to the agency's own accounting, Metro freeway widening is set to generate much more greenhouse gas emissions than all of its transit initiatives would save.

The 57/60 project adds one more eastbound general purpose lane to the 57/60 confluence. It adds new and widened on- and off-ramps (including two mile-plus long new bypass ramps to and from Grand Avenue), and widens Diamond Bar streets leading to the freeway trunk. Overall, the project adds just over eight miles of new lane miles for drivers. In addition, the project includes about 600 feet of isolated bike lanes, and widens Grand Avenue Bridge sidewalks from five feet to eight feet.

The 57/60 widening does not demolish any homes or businesses, though it does take some sliver portions of a couple business parcels toward the north end of the project - near Diamond Bar Boulevard. Most of the freeway widening will be accomplished by taking nine acres of public parkland, shrinking and traversing the county's Diamond Bar Golf Course.

For more information on Metro 57/60 Freeway widening, see earlier SBLA coverage from earlier this month, and from April 2021. Project updates may be available at the 57/60 project InstagramFacebook, and Twitter accounts.

57/60 Freeway
2020 Metro 57/60 Freeway widening map. As of January 2023, nearby road widening (in blue) and golf course reconfiguration/shrinking (in green) are currently under construction.
57/60 Freeway widening project diagram - via Metro fact sheet (diagram omits project adding one new eastbound general purpose lane)

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