To view the Plank Road Interchange Project alternates in detail, please click here.

The alternates’ analysis for the Plank Road Interchange Project includes the development of two alternative configurations, one each for Level of Service (LOS) (See glossary for definition) C and D, to evaluate right-of-way impacts, traffic flow improvements, and anticipated construction costs. Ideal conditions would allow LOS C operation twenty (20) years after the completion of the project. Although this is ideal, a LOS D can be considered acceptable to minimize significant impacts.

Both alternates include widening of the existing pavement from five (5) to eight (8) lanes on Plank Road and five (5) to six (6) lanes on Goods Lane, replacement of the I-99 bridges, improvements to the Plank Road/I-99 interchange, and replacement of the existing drainage system. In order to obtain the LOS C for design year conditions, additional pavement widening at the northern, southern, and western limits of the project are necessary to provide additional turning lanes. The intersection of Plank Road and Goods Lane/Orchard Avenue is currently being studied in greater detail. The design team will identify options which will increase the level of service for design year traffic volumes.

In addition to the intersection improvements, the Plank Road interchange is also being studied to improve traffic flow through the interchange area. The first alternate for the interchange is an upgrade of the existing ramps to provide additional turning lanes and room for vehicles waiting to turn onto Plank Road. The second interchange alternate is a Single Point Urban Interchange configuration (see the illustration to the right). This alternate consolidates all left turn movements to a single signal located under the overhead structures. Both interchange alternates are compatible with either the LOS C or D alternates for Plank Road.

In addition to Level of Service, anticipated construction costs, right-of-way impacts, and public feedback will be considered when the project team chooses a preferred alignment, for further design and future construction.