Inspection of the Coos Bridge utilizing traditional inspection access such as under-bridge inspection vehicles or ladders was not possible due a 5-ton live load posting of the bridge and location in a deep valley. We utilized rope access techniques to provide the required NBIS Routine and Fracture Critical hands-on inspection.
The Coos Bridge is a 50’ long single span through girder structure built in 1919 consisting of two rolled shape girders, four rolled shape floor beams and timber stringers and deck. To provide access for our inspectors, we retained a subconsultant to provide rigging of the bridge for rope access and completed the NBIS Routine and Fracture Critical inspection during the month of February. The rope access allowed for close up and hands-on inspection of the fracture critical bridge in accordance with NBIS criteria while not impacting traffic across the bridge.
SERVICES
NBIS Bridge Inspection
Report Preparation
From the blog
Learn about ongoing projects and the innovative processes we employ for our clients.
In northern climates, winter is more than a season – it's a construction variable. For airport projects in particular, cold-weather conditions can shape schedules, budgets, and even the quality...
Key Takeaways from The Wildlife Society’s Recent Webinar The Wildlife Society recently hosted a national webinar (led by Dr. Patricia Cramer) focused on the growing importance of wildlife connectivity...
Insights from the People Who Support Your Ground Transportation Infrastructure Every Day As we head deeper into 2026, we asked our ground transportation team one simple question: “What do...
Hoyle Tanner is currently providing wastewater engineering design services for the Town of Richmond, Vermont, to assess and develop alternatives which address the urgent need to upgrade the existing...
Hoyle Tanner’s Chelmsford office expansion is officially complete! After months of planning and coordination, construction was completed earlier this year to expand the office footprint, including the removal of...
We’re proud to announce that Jeffrey “JJ” Hollstein has earned his Professional Engineering (PE) license! JJ is a structural engineer in our Ground Transportation Division (Chelmsford office), where he...
As we close the chapter on 2025, we’re proud to reflect on a year defined by meaningful progress for our teams, our clients, and the communities we serve. Across...
Meet Stephanie Bishop – Structural Engineer & Lifelong Learner What drew you to Hoyle Tanner? Back in 2017, I was introduced to Hoyle Tanner as a high school intern...
The intersection of wildlife habitat connectivity and transportation is receiving growing national attention as the impacts of wildlife–vehicle collisions on public safety, ecosystems, and the economy become increasingly well...
