Metrolink’s 91/Perris Valley Line rail extension provides much needed relief to commuters along the I-215 and SR-91 freeways in Riverside County, CA. STV has been a long-term partner of the Riverside County Transportation Commission (RCTC), and was first contracted by the commission to perform planning, environmental studies and reports when the project was proposed, and then providing engineering and construction support after the extension broke ground.

The 24-mile line runs from the Riverside-Down Station to the City of Perris, with four stations along the extension at Riverside-Hunter Park, Moreno Valley/March Field, Perris-Downtown and Perris-South. The extension also connects the new stations to a route that operates between Los Angeles Union Station and Riverside. STV's scope of work included designs for the four stations, as well as the upgrade or closure of 16 grade crossings, sound walls, a layover facility, crew building and inspection areas.