The Ambassador Bridge across the Detroit River is closer to maximum vehicle capacity than was previously believed, according to a study released by the Booker T. Washington Business Association in Detroit. To help alleviate delays, the group advocates a proposed Jobs Tunnel, which would convert an existing train passage below the river into a two-lane truck route, with an enlarged train tunnel added alongside.

"The benefits of building the Jobs Tunnel are substantial and striking," notes Michael H. Belzer, the lead author of the economics team which produced the report. It "will double truck-crossing capacity and save truckers -- and shippers -- between US$1.3 billion and US$1.8 billion annually over the next 27 years."

Belzer and his team calculated that the bridge system -- including the bridge itself, access roads, toll plazas and government checkpoints -- is generally "at 92 percent of capacity ... (and) significantly exceeds capacity during many hours of the average workday."

The team spent six months examining the Detroit-Windsor border, the world's busiest border with US$92 billion in annual trade. An average of 10,000 trucks a day cross the bridge, using one lane in each direction and slowed by clogged approach roads in Windsor, a sharp curve for U.S. bound trucks and "a significant grade" averaging 4.5 percent on the bridge, the report says. "The current estimated capacity of the bridge system for trucks traveling from the U.S. to Canada is 395 trucks per hour (for trucks traveling from Canada to U.S. it is 315 trucks per hour) and this number will not increase without building a new crossing," Belzer concludes.