After almost 100 years in operation, the Grand Avenue Bridge over Walnut Creek at 63rd Street is being retired, meaning commuters will have to find an alternate route until a new bridge is built.

The city of Des Moines said in a release that the bridge will officially close on May 14 and won't be open for traffic until November. Jencoe Construction Inc. won a $3.3 million contract to replace the bridge.

The Grand Avenue Bridge was originally built in 1914, according to the release, and carries approximately 18,000 vehicles each day. During the past 98 years, the bridge was widened once in 1935, but has continued to deteriorate. 

In November, the city expects to open three lanes of the new bridge to traffic, while two remaining lanes are finished. The city expects construction to last into 2013. 

All stores on Grand Avenue in the area will remain open during construction, according to the city. The Walnut Creak Bike Trail is expected to remain open through the majority of construction and will be realigned with the new bridge. 

The city has set up a detour route for commuters to use during construction. For passenger vehicles, the city has asked drivers to take 63rd Street across the interstate to University Avenue, then back down 56th Street to Grand Avenue, if traveling east on Grand, and vice versa if traveling west on Grand. For truck traffic, the city has recommended drivers use 42nd Street instead of 56th Street.