All coastal train service in San Diego County will be temporarily suspended Saturday and Sunday for scheduled track maintenance and to advance two construction projects during what transit agencies call an “absolute work window.”

In Carlsbad, the weekend work will include excavation, utility relocation, and building a retaining wall within the Batiquitos Lagoon. The project there includes the construction of a second set of railroad tracks and a concrete-and-steel, double-track bridge to replace a wooden trestle from the 1940s.

The Batiquitos project is part of plans to double-track the county’s entire coastal route, about 75% of which has been completed so far. The second set of tracks allows trains to pass each other and is intended to improve rail service and boost ridership.

Del Mar residents could hear noise from construction equipment and see bright lights illuminating work areas at night as part of the ongoing bluffs stabilization effort expected to continue there through mid-2027.

Work in Del Mar includes the installation of drainage ditches within the railroad right-of-way between Sixth Street and Coast Boulevard. The multi-year project also includes the construction of additional seawalls and concrete-and-steel pilings to secure the tracks on the eroding bluffs.

Adding to the inconvenience in Del Mar this weekend will be several street closures from about 6:30 to 8:30 a.m. Saturday for the La Jolla Half Marathon, which begins its route at the fairgrounds before running a course through the town.

The railroad projects are a cooperative effort by Caltrans, the San Diego Association of Governments, and railroad right-of-way owner North County Transit District.

During the suspension, no Coaster, Amtrak or BNSF freight trains will operate on the route between the Oceanside Transit Center and the Santa Fe Depot in downtown San Diego, according to NCTD officials.

However, test trains, construction vehicles and equipment will be active on the railroad right-of-way and the tracks throughout the weekend. Residents along the corridor should remain alert, and people should only cross the tracks at lawfully designated rail crossings.

Weekend train suspensions occur periodically throughout the year so crews can work safely on routine maintenance and advance major improvement projects.

After this weekend, the next work windows this year are scheduled for Oct. 17 and 18, and Nov. 7 and 8.