Bergmann Associates developed the interchange designs for NYS Route 17 at Exit 122 in Wallkill, New York. The USD 68.5 million project included interchange reconstruction and realignment, as well as new and reconstructed bridges. NYSDOT required the designs to address sharp curves on ramps, close proximity of exit and entrance ramps that contributed to a high accident rate, vehicular delays at the ramp terminals, and a steep grade on the local road as it passes over Route 17.
During preliminary design, Bergmann was tasked with developing five complete interchange design alternatives. Using MicroStation and InRoads, Bergmann’s design team developed complex horizontal and vertical alignments to minimize impacts to environmentally sensitive areas. MicroStation-rendered photorealistic simulations helped the public visualize the alternatives. During final design, the geometry was further refined using InRoads’ advanced tools.
The preferred interchange alternative included new on and off ramps for NYS Route 17, arterial roadway realignment, large signalized intersections, a new bridge over NYS Route 17, a canoe launch, and a park and ride facility. Detailed cross sections were annotated using Bentley’s automated workflow, cutting production hours in half. Extensive use of Bentley products helped the project earn the Evergreen award through the Green Leadership in Transportation and Environmental Sustainability program.
With multiple design firms and disciplines involved, it was imperative that responsibilities be well-defined to avoid interference between design components and to ensure accurate calculation of project quantities. This was accomplished by using MicroStation and InRoads to develop 3D solid models and 3D digital terrain models to aid in design, coordination, detailing, and estimating. ProjectWise managed file sharing and coordination.