Firm: Strand Associates Inc.
Client: Wisconsin Department of Transportation
Location: Madison, WI
The USH 18/151 is one of the key transportation crossroads in southern Wisconsin. Carrying up to 110,000 vehicles daily, $13 billion in freight annually and supporting 393 businesses within a half mile radius, its impact is far greater than a simple state highway interchange would suggest. Any design had to modernize the system to keep up with growing demand while keeping routes open during construction. The entire project encompassed multiple interchanges, multi-modal paths and bridge reconstruction in less than a mile radius.
Strand Associates approached each of these problems with innovative design solutions. To facilitate bike and pedestrian traffic, two separate bridges and a tunnel were created to increase safety, reduce congestion and keep neighborhoods connected. A specialized jug-handle interchange design was put in at the intersection of USH 151 and a local road. The first of its kind in Wisconsin, it incorporates a roundabout underneath the highway and uses 2 million pounds of steel to support the structure above and improve roadway visibility. At the actual intersection between USH 18 and USH 151, the design team created a single-point urban interchange with offset piers. This is the first of its kind in the US. This design reduces traffic conflict points which speeds up the commute and lowers the risk of accidents. The two span structure above saves money and doesn’t interfere with traffic. It is estimated this new design will save 250,000 hours of traveler delay annually.
Said awards judge Anna Varney, PE: “Even with all the engineering complexities, the needs of the community were incorporated in the project through context sensitive designs, as well as providing neighborhood connectivity and safety with improved mobility of the sidewalks, trails, paths, bus accommodations, and grade separated crossings, all while completing the project on schedule and under budget”.
This incredible project highlights both the complexity of transportation systems and the crucial role professional engineers play. The new design increases safety and decreases time wasted by drivers in traffic. Strand provided a great design for motorists, local businesses and pedestrians with multiple innovative solutions.