Kansas Turnpike Authority President Michael Johnston will chat online about the Kansas Turnpike project that will see new bridges built over the Kansas River and upgrades made to the Lawrence toll booths.

KTS Kansas River Bridge construction

Think of it as the “mother of all projects.”

That’s how Mike Johnston describes what will be a $140 million, three-year effort to replace the turnpike bridges over the Kansas River in Lawrence – and rebuild the city’s two interchanges.

“It’s a huge project for us,” Johnston, the Kansas Turnpike Authority’s chief executive, said during an informational meeting Tuesday at the Lawrence Visitor Center.

“It is going to entail some very challenging traffic management issues for the community,” he said.

The project is necessary because by 2012 the bridges will have reached the end of their serviceability, Johnston said.

“The bridges have to be replaced,” he said. “That’s not discretionary. It is going to be a real trying experience from time to time.”

Bid-letting for the project is set for May, and construction on a new westbound bridge is expected to start in June.

The new westbound, three-lane river bridge will be constructed just north of the existing bridges, said KTA project engineer Rex Fleming.

“It will be a much larger structure than what we have now,” Fleming said.

The new bridges will span 2,300 feet.

Motorists definitely will notice when work begins next summer on the east and west Lawrence interchanges.

A bridge over the turnpike carrying traffic from the west Lawrence toll plaza to the westbound lanes will be torn down. That means motorists who use that entrance to the turnpike to head to Topeka and beyond will have to use other entrances for about eight months.

In mid-2009, the second phase of the project will start, when all traffic in both directions is moved onto the newly constructed bridge over the river. Construction on a new eastbound bridge will start next and the old bridges will be torn down.

In addition, the east Lawrence toll plaza will be closed to all traffic for eight months while it is rebuilt. The new toll plaza will be larger than the existing one.

The final phase will come in 2011 with completion of the eastbound bridge and resurfacing along the 2-mile corridor between the two interchanges. Taller concrete barriers will be installed in the median.

Consideration was given to options that would keep the east Lawrence toll plaza open during reconstruction but it would take longer and add to the cost, Johnston said. KTA representatives said it would extend the construction project by at least a year and add $9 million to $10 million to the cost.

“We didn’t look seriously at it because one of the chief goals is to get it done as soon as we possibly can,” Johnston said.

Rebuilding the interchanges will mean they can handle increased traffic. About 31,000 vehicles a day travel by Lawrence on the turnpike, Johnston said. Traffic increases by about 1.5 percent each year, he said.

Several city, county and public safety officials attended the meeting.

“We’re going to need to closely coordinate with them (KTA) in regards to the impact this is going to have on the community; particularly, the plaza closings are going to be a significant impact to the traveling public and the nearby businesses,” City Manager Dave Corliss said. “We want to make sure we’re not going to be repaving a road that will be an important detour.”

Douglas County Commissioner Bob Johnson said the turnpike improvements – although inconvenient – will have a positive effect on the area.

“People will get awfully frustrated at times,” he said. “I’ll probably be one of them, but three years is a relatively short period of time.”