MoDOT, District 8, Springfield -- One northbound and one southbound lane of National Avenue on the bridge over James River Freeway (Route 60) will be closed during daytime hours beginning Thursday, Oct. 1, and lasting into the week of Oct. 5, the Missouri Department of Transportation said.

Contractor crews will begin removing a concrete median down the center of the bridge.

Crews will close the lanes between 9 a.m. and 3 p.m. Thursday and Friday, Oct. 1-2.

The outside through lane will be open in each direction and a very short left-turn lane will be available for National Avenue drivers who need to access the James River Freeway. Driving delays are expected during the work.

No work is planned over the weekend and all lanes on National Avenue will be open to traffic.

However, on Monday, Oct. 5, crews will resume work on the National Avenue bridge. Each day through the week, a lane in each direction on the National Avenue bridge will be closed during the day.

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

Early Heads Up

Starting the week of Oct. 19, more extensive work is scheduled to begin on the project. That's when long-term lane closings and traffic shifts will be needed on National Avenue between Bradford Parkway north of the bridge and Kingsley Street south of the bridge over the James River Freeway.

Drivers can expect slow-moving traffic with delays getting through the work zone, with workers and equipment set up very close to traffic.

Project Details

* Widen the National Avenue bridge (10 feet on each side) over James River Freeway to provide three lanes in each direction across the bridge. The bridge is in good condition and does not have to be replaced or undergo significant repairs. The bridge deck will be sealed.

* Widen ramps. Dual right-turn lanes will be provided from westbound James River Freeway to northbound National Avenue.

* Build a pedestrian walkway down the middle of the National Avenue bridge.

* Add a lane in each direction on National Avenue south of the bridge to Kingsley Street and north of the bridge to Bradford Parkway.

* Build an additional lane in each direction on the James River Freeway connecting the ramps at National Avenue and Campbell Avenue.

* Build a service road and underpass underneath National Avenue north of James River Freeway to improve connections between CoxHealth facilities on both sides of National Avenue and provide safer entry to Cox South Hospital, including its emergency department. This also will improve traffic flow and safety for drivers on National Avenue going past the CoxHealth facilities.

* Convert the interchange into a Diverging Diamond Interchange design where the opposing lanes of National Avenue will criss-cross at traffic signals at the ends of the bridge over the James River Freeway. Crossing the bridge, oncoming traffic will be on the right. Opposing lanes will be divided by concrete barriers, with a pedestrian walkway in between the walls.

This configuration will provide left-turning vehicles on National Avenue a "free left" onto the James River Freeway ramps. At the same time, traffic continuing north or south on National Avenue will be able to travel more steadily through the interchange, reducing backups. Signs, pavement markings and concrete islands will clearly guide drivers and help prevent making a wrong turn into the opposing lanes.

The project at National Avenue and the James River Freeway will cost $9.7 million, including $7.5 million for construction and $2.2 million for engineering and right-of-way acquisition. Springfield, CoxHealth and MoDOT will share the cost.

The prime contractor is Emery Sapp and Sons of Columbia. The project is scheduled for completion in August 2010.