Route 336, Section 55-2

Location

Macomb, Illinois

 

Client

Illinois Department of Transportation – District 4, Region 3

 

Services provided

Hydraulic engineering

Route survey

Structural engineering

Transportation engineering

 

Project overview

The Illinois Department of Transportation (IDOT) required Phase II design engineering services for an 8.6-mile four-lane rural expressway on a new alignment. The project included two separate crossings of the BNSF Railroad involving five bridge structures and extensive drainage and erosion control measures. The project was to be connected to the existing US Route 136 with provisions for connecting to an improved section at the west end.

 

Approach

STS provided design engineering services including a dual highway structure to bring Route 336 over the BNSF Railroad eight miles west of Macomb, IL. The project also included five other bridge structures, including three railroad structures to carry the railway over the ramps and the mainline at the interchange of 336 with Route 136 near Macomb.

 

STS provided topographical and right-of-way surveying; highway drainage design; preparation of type, size and location plans for structures; complete structure plans for five bridges and several large culverts; preparation of right-of-way plats; and preparation of plans specifications and estimates for the entire project.

 

The design of the Route 336/Route 136 interchange included final design of the outer ramps of the Parclo interchange. Special slope considerations were included in the eastern half of the project area where some deep cuts and high fills were necessary, in addition to the lake adjacent to the mainline roadway.

 

Client benefits

• STS found that it was more economical to construct the roadway under the railroad at the interchange. This significantly reduced the projected cost of the project and improved the vertical alignment for the future roadway east of the interchange.
• To advance the construction of the project by one year, the plans were divided into a grading and structures contract and a final paving and structure contract.