Project Description

CH 21 Bridge over Lake Fork Creek
Macon County, IL

The bridge carrying County Highway 21 over Lake Fork Creek in Macon County was in need of replacement. The County utilized Federal Funds for construction of the new bridge. Phase I and II reports, studies, and plans were prepared according to State and Federal requirements.

The new bridge consisted of a three span continuous cast-in-place slab bridge with integral abutments and solid wall encased pile piers. The bridge was built on a zero degree vertical grade but utilized Type SM bridge railing to allow deck drainage. The steel railing also reduced the out-to-out width of the bridge deck and provided a significant cost saving while meeting the required crash test level. The total bridge length was 81’-8″ with outer spans of 25’-3″ and a center span length of 31’-2″. The bridge width was 28’-0″ between railings, the substructure was founded on metal shell piles, and a shortened concrete approach pavement was utilized.

Phase I planning including preparation and submittal of all required documentation including the Bridge Condition Report, Hydraulic Report, Environmental Studies, Joint Application, and Project Development Report. In-house work included survey, hydraulic analysis, environmental investigations and reporting, roadway and bridge design. Geotechnical borings and the Structure Geotechnical Report were prepared by another consultant and the effort coordinated by Clark Dietz.