Maine’s Piscataqua Bridge on I-95 is described as Maine’s gateway to the rest of New England and the nation. When it was built, traffic volumes were a fraction of what they are today. Now, approximately 74,000 vehicles cross the bridge on an average day, with summer traffic peaking at 130,000 vehicles each day. This high traffic volume creates congestion; traffic can back up for miles on summer weekends. Dated railings diminished safety confidence, and drains malfunctioned, damaging the structure. The bridge needed an upgrade to continue to move people and goods safely and efficiently.
Because of the location and nature of this structure, shutting this bridge down to implement a detour is not practical. A unique solution came in the form of a “zipper truck,” a vehicle specially designed to relocate concrete barriers an entire lane width quickly and in a single pass. Using conventional methods, relocating one mile of barriers would take hours. Using a “zipper truck,” this change can happen in a matter of minutes. This allowed crews to shift lanes over while remaining behind concrete barriers to perform work safely. Maine DOT’s $52.6 million rehabilitation now allows people to move across this vital bridge easier and more safely.