New Mississippi River Bridge Project, United States of America

The new Mississippi River Bridge is the first bridge to be built in the past 40 years over the Mississippi river connecting St Louis and Illinois. It will be the third largest cable-stayed bridge in the US upon completion.

The structure was officially named Ronald Wilson Reagan Memorial Bridge in August 2005. It will be located one mile north of the Martin Luther King Bridge.

The states of Illinois and Missouri obtained approval from the federal government to build the bridge and associated roadways in 2001. The project was estimated to cost from $1.8bn to $2.2bn approximately.

Lack of sufficient funds to simultaneously construct all the components, however, forced Illinois and Missouri to redesign the bridge to a simpler one.

The redesigned project is estimated to cost $667m including land acquisition, relocation and construction.

The new bridge will reduce the traffic congestion on the Poplar Street Bridge which links St Louis of Missouri to Eastern Illinois. It will reduce the accident frequency and also the travel time. It will also improve system linkages and community access.

The ground breaking ceremony of the project was conducted in April 2010. The bridge is expected to be complete and opened to traffic by 2014.

Mississippi River Bridge project

The project involves construction of a new bridge across the Mississippi river, construction of the Mississippi North I-70 interchange and Illinois I-70 connection and the improvement of I-55/64/70 tri level interchange.

The entire project spans 6,460ft including the Illinois approach, the main bridge and the Missouri approach.

The new cable-stayed bridge will link St Louis of Missouri to the St Claire County of southwest Illinois. It will be linked to the I-70 roadway and downtown St Louis by the Mississippi I-70 interchange.

The Illinois I-70 connection will be connected to the new bridge so the I-70 traffic crosses the river using the new bridge crossing.

The existing tri level interchange meets at the Poplar Street Bridge. The area will be improved and new ramps will be added to and from the bridge.

The project will also involve demolition and reconstruction of the Cass Avenue Bridge and St. Louis Avenue Bridge.

Improvements are also being planned for future. A new bridge with four additional lanes is planned to be built adjacent to the new Mississippi River Bridge.

The Missouri interchange and I-55/64/70 tri level interchange will witness additional improvements. The relocated I-70 will be extended to I-55/70 interchange of Illinois.

Bridge design specifications

The four-way cable-stayed bridge will be 457m (1,500ft) long, 26m wide and 122m high. It will have two single-pylon towers, a nine degree inclination from the river and three planes of cables.

It will be connected to the Illinois and Missouri approaches at its two ends. The pylon towers will be 400ft high above the water level.

Construction of the bridge linking St. Louis and Illinois

Construction works were initiated in 2010. The test shafts were bored into the river in early 2010 and foundation was laid for the construction of the bridge.

Ground breaking ceremony on the Illinois approach was conducted in August 2010. Reconstruction on the St. Louis Avenue Bridge, which was demolished in June 2010, was completed in 2010. The bridge was opened to traffic in November 2010.

Steel cofferdams were constructed on both sides of the river and around 3,000 cubic yards of concrete was poured on both ends of the river in early 2011. Girders of 6ft height and 145ft length, and precast concrete panels were also placed in early 2011.

Foundation works for the construction of the main bridge neared completion by spring 2011. A framework was built on both ends of the river by using approximately 1.9 million lb of steel.

Girders and concrete panels were placed on the Missouri approach in spring 2011. The girders are 6ft tall and have a length ranging from 115ft to 145ft.

Construction works are in progress at the Illinois approach and Missouri Approach. Piers are being built for the support of the approach.

Building works on the Cass Avenue Bridge were initiated in August 2011 and it was inaugurated in January 2012.

Construction works on the new bridge at Exchange Avenue over the I55/70 and the one over the I64 are in the final stages of completion as of January 2012. A new bridge will be built on the relocated I-70.

Work on the mainline I-70 has been initiated and construction is also in progress on the curved structure over the industrial drive.

Contractors involved in construction

A $229.5m contract for the construction of the main span of the bridge was awarded jointly to Massman Construction, Traylor Brothers and Alberici Constructors in November 2009.

Modjeski and Masters were appointed to conduct the bridge studies and prepare the preliminary and final bridge design.

A Keeley-Keller joint venture has been appointed for the construction of the Illinois approach. The $4.4m preliminary works contract was awarded to Freb Weber in June 2009. The works include the replacement of the Madison Street Bridge and the St Louis Avenue Bridge.

Financers of the Mississippi project

The project will be jointly funded by the Federal and the State governments. Illinois Department of Transportation, Missouri Department of Transportation and Federal government will contribute $313m, $115m and $239m respectively.