The Wisconsin Department of Transportation (WisDOT) is on track to open two ramps on the Zoo Interchange system this week.
The ramp connecting eastbound I-94 to northbound I-41 is scheduled to open on Wednesday. A day later, the ramp connecting southbound I-41 with the eastbound lanes of I-94, as well as the Wisconsin Avenue Bridge going over I-41, will open.
The three openings will come as the most significant milestones reached this season amid work on the Zoo Interchange’s second core phase—a $300 million, three-year project. Work on the Zoo Interchange project’s first core phase wrapped up in June last year. The second phase is expected to be complete by late summer 2018.
The Zoo Interchange is among the largest projects in WisDOT’s history. The nearly 50-year-old interchange is already the most used in the state, and it is likely to get busier. Its daily traffic count, currently at 350,000 vehicles, is expected to increase to 410,000 vehicles a day by 2035.
For months, work on the interchange has moved traffic to detours onto smaller highways and local streets to go to and from the various freeways that converge in the area. With the ramp reopenings next week, drivers will again be able to use the interchange to make those connections. The resulting traffic reduction should be especially welcome to travelers during the state’s tourism season, which generally starts with Memorial Day weekend.
The interchange’s new configuration is far better suited to current traffic counts than was the original design, which dated to the 1960s. Among the features to help traffic flow are various “collector” roads that will take vehicles out of mainline traffic before they reach their exit ramps.
Once finished, the entire interchange project will have 9 miles of reconstructed freeway, 3.5 million miles of steel rebar, 100,000-plus cubic yards of concrete, more than 100 retaining walls and 73 bridge structures. WisDOT engineers estimate it will be 75 years before the Zoo Interchange needs to be rebuilt again.