Known as the Great River Road to tourists, state highway (STH) 35 is a heavily traveled route that required safety upgrades. The complex project had several construction stages and a range of work including adding two roundabouts. In addition to the roundabouts, ISG replaced the watermain, culvert pipe, and storm sewer, extended box culverts, added modular block and mechanically stabilized earth retaining walls, constructed multi-use trails, and improved intersections and roadway surfacing. Balancing the busy road with the necessary improvements, ISG successfully phased and allowed traffic during construction.