Southwest Adams Avenue will close between Baseline and Walnut streets in Hillsboro for improvements to the aging rail. (Courtesy of Google Maps)

As Hillsboro moves into the second phase of its multiyear rail replacement project along Southwest Adams Avenue, downtown drivers can expect a new round of road closures and detours.

Scheduled between July 30 and Aug. 7, construction will fully close Southwest Adams Avenue between Baseline and Walnut streets, the city of Hillsboro announced. The work zone also includes the intersection at Southwest Oak Street (Oregon Highway 8), which will be closed to through-traffic between Southwest Dennis and Southwest Adams avenues.

Lane closures will remain in place 24 hours a day, seven days a week during the project window.

Detours will direct traffic from Southwest Dennis Avenue to Southwest Walnut Street, then south on First Avenue to reconnect with Oak Street. The city encourages travelers to plan ahead, follow the posted signage and avoid the area if possible.

This year’s work extends the upgraded rail corridor by another 500 feet, building on the first phase’s work to replace tracks south of Washington Street. The second phase mirrors the previous scope of work: removing aging rail, installing a new solid base, adding new track and concrete panels and repaving the affected roadways.

Access to local businesses will remain open throughout construction, according to city officials.

Another closure is tentatively scheduled Aug. 11-15 at the railroad crossing on First Avenue, where similar repairs are planned. That closure will require a full shutdown of the highway in both directions, with the city coordinating with the Oregon Department of Transportation and the railroad operator to provide updates about detours.

Funding for the rail improvements is covered through the city’s 2025-27 budget through Pavement Management Program contracts supported by the transportation utility fee.