Michigan DOT advertises I-75/I-96 Ambassador Gateway contract

Yesterday, Michigan DOT advertised the main contract for the I-75/I-96 Ambassador Gateway. This project will make major improvements to the connections among the Ambassador Bridge, the two Interstates, and the local street system. It includes a signature cable-stayed pedestrian bridge to connect the two halves of Bagley Ave. which were severed by construction of I-75 and I-96 plus a number of flyover ramps, some of which lie within the current toll plaza approach, to connect the freeways more directly with the Ambassador Bridge.

Google Maps covers the project location in its current state. To indicate the scope of what is planned, I have created two photo maps by overlaying extracts from the plan sheets over aerial photos downloaded from Google Earth. (Note that while north is up in Google Maps, north is generally to the right--but not at precisely the same angle--in these extracts.) The first gives a general overview of the project.



The second gives more detail of the spaghetti-like arrangement of ramps in the vicinity of the toll booths and Customs plaza:


Bid opening for this project is currently scheduled for June 8, 2007. Michigan DOT does not publish estimates of construction contract value as part of the advertisement process, but the 2006-08 TIP for the Southeast Michigan Council of Governments (the MPO for Detroit and vicinity) allocates a total of $150 million for this project.

Contractor outreach started early for this project, in what I take to be another indicator of its size and importance. On February 27, 2007, Michigan DOT announced a pre-advertisement constructability review meeting to take place in Lansing on March 16, and also published sketches showing the geographical scope of roadway (11 MB) and bridge (21 MB) construction required for this project. The project website was unveiled on April 20 but still has only the bare bones.