Naperville's Jefferson Street Bridge closing Monday

Several thousand Naperville motorists - and walkers - will have to alter their commutes for about six months beginning Monday as the Jefferson Avenue Bridge is removed and rebuilt.

Naperville officials said the 48-year-old bridge spanning the West Branch of the DuPage River carries about 6,500 cars a day and has begun to deteriorate.

"The bridge is getting older and coming to the end of its life," project engineer Sean Marquez said. "It is still structurally sound but it is to the point where normal maintenance will not benefit the bridge and so it needs to be replaced."

During construction, traffic will be detoured to Ogden Avenue along River Road on the west side and along Mill Street on the east side.

The pedestrian and cyclist detour route will direct residents on the west side of the bridge to go to Aurora Avenue to Eagle Street to reach downtown. The route is about a half-mile longer than going over the bridge and will add about 10 to 15 minutes to the walk.

When the $3.5 million project is complete, no later than Aug. 27, the new two-lane bridge will span from Willoway Drive to Parkway Drive and be wide enough to accommodate vehicles, bicycles and protected sidewalks.

The city is only on the hook for about $700,000 with the remaining 80 percent of the work paid for by state and federal grants.

Residents can receive e-mail alerts on the project by registering at www.naperville.il.us/enews.aspx.