Illinois Department of Transportation, District Two
IL 40 over the Rock River, Whiteside County, Illinois
Chastain completed a Phase I study in 2009 for the complete removal and replacement of a 12-span bridge carrying IL 40 over the Rock River between Sterling and Rock Falls. The project included geometric studies to provide a wider proposed bridge in a constrained urban area and realignment of the approach roadways. The bridge has buildings located directly adjacent to it at both ends of the structure. Work also included preparation of Location/Design Report; traffic management analysis; cost estimate; TS&L; roadway, drainage and traffic signal plans; drainage system design; and field survey. Phase II design plans, specifications and estimates were completed in 2011. The new 8-span, 1030' long steel plate girder bridge provided four lanes of traffic, 11' multi-use paths on each side of the road, scenic overlooks adjoining the multi-use paths, decorative railing, and overhead decorative lighting. Environmental studies and coordination with IDNR and IEPA addressed threatened mussel species along with other socio-economic and environmental issues. Chastain was among the first consultants in District Two to incorporate Context Sensitive Solution principals to achieve community consensus regarding design features. First and Second Streets in Rock Falls and Wallace and Second Streets in Sterling all lie within the project limits and were significant considerations in development of the geometric alignment and profile, as well as maintenance of traffic plans for the wider IL 40 bridge. Chastain was the first consultant to prepare a Transportation Management Plan for a District Two project. Chastain received a "Good" in our final evaluation from the District for our Phase I performance noting "…consultants work was presented in a concise manner and required minimal review time." Construction was completed in 2012 with a total construction cost of $25 million.