Workers will start tearing down the crumbling Wisner Boulevard bridge over Interstate 610 next week to make way for a new, wider overpass.

The $19.5 million project is scheduled to get underway Dec. 10 and to wrap up in early 2017.

The existing concrete-girder bridge will be demolished and replaced with a steel-girder span.

The new overpass will measure about 65 feet across — eight feet wider than the existing, half-century-old span — and will include two 12-foot-wide travel lanes in each direction. It will have a 12-foot-wide pedestrian and bike path.

It’s a joint project of the city and the state Department of Transportation and Development.

During construction, lakebound traffic will be detoured to Desaix Boulevard and St. Bernard Avenue. Riverbound traffic will be detoured to Harrison Avenue and Marconi Drive.

The work will generally take place on weekdays from 7 a.m. to 5:30 p.m., although some work may be done at night.

The contractor, Boh Bros. Construction Co., will be permitted to close I-610 on as many as three weekends during the construction.