Greene County -- Work begins Tuesday, Sept. 4, on a project to replace the West Bypass (Route 160) bridge over Interstate 44 in northwest Springfield, the Missouri Department of Transportation said.

The bridge will be replaced one side at a time. That means traffic will be shifted and reduced to one lane in each direction across the part of the bridge that is still in use.

Drivers who use West Bypass regularly can expect delays, especially during morning and afternoon rush hours.

The project also will require I-44 underneath the West Bypass bridge to be closed for parts of two weekends. That way contractor crews can tear out half of the bridge so the new half-section can be built.

Timeline

* Week of Sept. 4: Lane closings on West Bypass over I-44 will allow contractor crews to remove a concrete median and islands. The work will prepare for two-way traffic in the near future.

* Week of Sept. 17: At mid-week, West Bypass traffic will be reduced to one lane in each direction and shifted to the west side of the bridge.

* Sept. 21 into Sept. 22: West Bypass will be CLOSED at I-44 and I-44 will be CLOSED underneath the bridge. Contractor crews will tear down the east half of the bridge.

The roads could be closed for up to 20 hours, beginning at 10 p.m. Friday, Sept. 21, and lasting as late as 6 p.m. Saturday, Sept. 22.

During the 20-hour closing of I-44 at West Bypass, people driving through Springfield on I-44 will be urged to use Route 65 (Mile Marker 82), Route 60 and Route 360 (Mile Marker 69) to get around the closing. Electronic message signs will be deployed with that advisory.

Big trucks especially are urged to use the Route 65-60-360 route.

While I-44 will be closed at West Bypass, the ramps at the interchange will remain open. However, drivers only will be allowed to make right turns onto or off of ramps. Traffic will NOT be allowed use the West Bypass bridge.

Weather and/or construction delays could alter the work schedule.

* February 2013: West Bypass will be traffic shifted to the new east-side bridge. Two-way traffic on West Bypass will continue as the west side of the bridge is removed and replaced.

Dates in February for a weekend closing of West Bypass at I-44 and of I-44 underneath the bridge will be announced.

The project also includes adding new traffic signals on West Bypass at the I-44 ramps on the south end of the bridge. The traffic signal at the north end of the bridge at the ramps will be replaced.

The prime contractor is Lehman Construction of California, doing the work for a low bid amount of $3.5 million.

The project is set for completion by late May 2013.

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