The construction site is located at the roundabout connecting Route 1 and 156th Street, which provides access to the canton of San Ramón in Alajuela Province.

As part of the project, crews are installing 24 pre-drilled foundation piles for the underpass roadway that will form part of the new interchange.

MOPT said the structural elements will serve as retaining walls for the underpass.

The underpass will include two lanes, one in each direction, along with internal and external shoulders, allowing vehicles to enter and exit Route 1 to access San Ramón.

The project will create a two-level roadway system, eliminating the roundabout between local canton roads and Route 1 that existed before construction began.

Once completed, vehicles traveling along Route 1 toward other provinces and the Pacific Coast will be able to continue without interruption on the upper level, improving traffic flow throughout the corridor.

The upper section of the highway will feature four lanes, with two lanes in each direction, as well as a central barrier and internal and external shoulders.

MOPT said construction of the foundation piles and the two-level roadway will require ongoing traffic control measures. Drivers are being asked to proceed with caution and comply with the maximum speed limit of 18 mph (30 km/h) throughout the construction period.

Work is taking place Monday through Saturday from 7 a.m. to 5 p.m. Officials said nighttime construction may also be necessary, with crews working from 6 p.m. to 2 a.m. when required.

Construction is expected to continue for at least seven months, with the new interchange scheduled to open in January 2027.

The San Ramón overpass project is estimated to cost $10 million and is being financed through a loan from the Inter-American Development Bank (IDB).

The work is part of a broader series of road improvement projects being carried out nationwide by MOPT. Last week, authorities installed a new bridge near Juan Santamaría International Airport in Alajuela Province.