The Project includes:

• Widening of Interstate 55 to 3 lanes in each direction between Route M and Route Z

• Resurface existing lanes in each direction between Route M and Route Z

• Straightening of the Interstate 55 southbound exit to Route M. It also removes the curve approaching the signal at Route M.

• Replace and widen Interstate 55 bridges over Route M and Glaize Creek

• Install new high tension guard cable after lanes are widened in the median

• To view the entire high tension guard cable pamplet click here (2 pages, 567 kb)

• Increase shoulders from 6 feet wide to 10 feet wide

Construction begins in March 2010 through 2012. Construction work will address the congestion problem by widening the interstate to 3 lanes in each direction and will address the safety issues by adding features such as median shoulders, new high friction pavement, and high tension guard cable. The project construction cost is approximately $ 15-20 million and was funded by the American Recovery and Reinvestment Act.

 



Construction Schedule and Impacts:

• Project began in March 2010.

• Two lanes will be open in each direction of Interstate 55 during peak hours.  Night time lane closures will be utilized for construction.

• During the construction of the bridges over Route M and Glaize Creek, the lanes of traffic will be shifted, the speed reduced (70 mph to 50 mph) and the lane widths reduced to 11 foot lanes over Route M.

• Northbound Interstate 55 exit to Route M will be closed during the bridge construction. (Spring 2010- early 2011) Traffic will be detoured to Route Z to Highway 61/67 to access Route M.

• Southbound Interstate 55 exit to Route M will have temporary closures to connect the Interstate to the newly aligned ramp.  The new ramp will be straighter approaching Route M.

• Operation Protect will be operating along Interstate 55 in Jefferson County.  This Missouri Highway Patrol program provides traffic and safety enforcement of work zones.  Interstate 55 was selected to participate in this program due to the number of severe crashes that occur in this area.

Noise analysis to be performed

A noise analysis is required whenever MoDOT widens an existing roadway.  MoDOT will use a federally approved traffic model to analyze the change in noise from the widened I-55 from Route M to Route Z.  The model looks at a 20-year noise projection.  Noise levels must be projected at greater than 66 decibels to require construction of noise abatement, which is typically a soundwall.  For more information on MoDOT’s soundwall policy, please click on:

http://www.modot.mo.gov/stlouis/links/docs/sndwalls_304.pdf