Motorists who typically use the Delaware River Bridge connecting the Pennsylvania and New Jersey Turnpikes should make new driving plans for the foreseeable future, officials urged Tuesday.

It will be at least two weeks before the nature of the bridge repairs is known, and making the fix will take longer, they said. As engineers attempt to diagnose and then repair the crack that forced the bridge's shutdown Friday, commuters likely will continue to experience significant delays on alternative routes.

Joseph Donnelly, Delaware River Joint Toll Bridge Commission spokesman, said Tuesday that Route 1 commuters traveling on the Trenton-Morrisville Bridge saw traffic backed up for about five miles, adding more than 20 minutes to the trip. On the Scudder Falls Bridge, commuters are experiencing delays of about 18 minutes.

Forty-two thousands cars typically traverse the Delaware River Bridge each day. The 61-year-old span was closed after a crack was discovered in a supporting steel beam beneath a westbound lane on the Pennsylvania side of the bridge, which runs between Bucks County in Pennsylvania and Burlington County in New Jersey.

As the engineers attempt to identify the cause of the crack, workers this week are  stabilizing the 1.2 mile-long bridge. In an interview with the Inquirer, Karl Frank, professor emeritus of engineering at the University of Texas at Austin, suggested the fissure was caused by holes drilled and filled with plug welds during its construction.

While the work continues, Donnelly said, morning commuters can expect heavy traffic volume, especially headed toward the Trenton and Princeton areas in New Jersey. Drivers can expect an extra 30 minutes just to get on local roads after getting off the Scudder Falls Bridge, he said.

Officials are encouraging commuters to carpool, use public transit, or arrange to work remotely

Staff Writer Ashleigh M. Albert contributed to this report.