The City of Concord initiated an intersection improvements project to support continued economic development within the Whitney Road and Exit 17 commercial and industrial districts.
VHB worked closely with the City to make major improvements to Hoit (NH Route 4) and Whitney roads, including the design of a hybrid two-lane roundabout at the intersection where the two roads meet.
Additional improvements included the reconfiguration of the entrance to the I-93 Exit 17 SB on-ramp to lengthen the separation distance between the on-ramp and Whitney Road and to moderate vehicle speeds within the interchange. VHB also redesigned the Whitney Road approach and developed a single-lane roundabout at the main development entrance. To manage high peak hour traffic volumes through the project site during construction, VHB implemented a multiphase construction phasing and traffic control plan. The finished condition included Pedestrian Hybrid Beacons (PHBs) to control pedestrian crossings of multi-lane Route 4, and Rectangular Rapid Flashing Beacons (RRFBs) to enhance the Whitney Road pedestrian crossings.
VHB also completed environmental permitting efforts, including a noise impact study for a nearby eagle nest, and designed stormwater detention and infiltration systems to conform to stormwater regulations. Additionally, VHB provided engineering support during construction and completed a post-construction as-built survey.
