Construction on the Mosquito Road Bridge in El Dorado County continues above the South Fork of the American River. Crews are now working toward the final connections that will link the bridge into a single, continuous span.

The project replaces the narrow, historic Mosquito Road Bridge with a new two-lane structure that will reduce a 1.3-mile winding canyon route to a 0.3-mile direct crossing between the Mosquito and Swansboro communities. The bridge spans more than 1,100 feet and rises about 400 feet above the river.

The project is being built by Shimmick Construction, working under contract with El Dorado County Department of Transportation.

Work over the past months has focused on building the bridge outward from its two main concrete piers in the canyon, using a segmental method in which sections are cast sequentially from the supports toward the center of the span.

Video captured Jan. 31 shows latest bridge construction progress.

Crews have also completed major concrete work near both ends of the bridge, preparing the structure to tie into Mosquito Road on the north and south sides of the canyon.

In a presentation delivered during a December town hall meeting, El Dorado County outlined that the bridge is expected to open to the public in June or July 2026. Officials said construction has moved forward steadily despite the challenges posed by the site’s height and terrain.

Work in the coming months will focus on closing the remaining gaps in the bridge, followed by installation of the driving surface, safety barriers, and railings, according to the county’s website. Roadway connections and final inspections are expected to follow before the bridge opens to traffic.

Once the new bridge opens, the existing Mosquito Road Bridge is expected to remain in place and be converted for bicycle and pedestrian use under a separate project.

Mosquito Road Bridge Map