Increasing regulations for impact to wetlands, streams, rivers, and other protected areas, as well as escalating rules about disturbance/flow restrictions and mitigation, have reduced developers’ options for developing in sensitive areas.

The Big Canoe Company in Atlanta, GA was facing these same concerns when developing a new community north of Atlanta. The area is home to 3 Lakes, 27 holes of championship golf, and numerous hiking trails in a mountainous setting with ridges exceeding 8,000 feet.  

York Bridge Concepts (YBC) was chosen to design and construct several Timber Bridges in the community to span protected areas and resolve these concerns. With this solution, the Big Canoe Company was able to save time and budget, while maintaining the aesthetic of the new mountain community.

Case Study
This new development required several bridges to span a wetlands area, a protected trout stream, and to form a trail system for this new housing community. Engineers had originally specified and priced prefabricated concrete and steel structures, but concern about permitting and logistical problems, as well as the developer’s preference for timber, prompted the engineer’s call to YBC.

Big Canoe’s Objectives
• Build four vehicular bridges and twelve pedestrian bridges throughout the development. Include a horizontal turn and elevation change on one bridge to meet original designs. Ensure the bridges blend into the surroundings.
• Overcome permitting concerns – steel pilings in this sensitive area would likely not be approved.
• Solve the logistical problem of getting prefabricated concrete slabs and an ornamental steel bridge to this mountainous, undeveloped site.
• Decrease turnaround time – approximate fabrication and installation time frame for the steel structure was 12 months.
YBC’s Solutions
• Meet design objectives through the creative use of timber design. With their extensive experience in arching and curving bridges, often through wooded areas, YBC’s design team was quickly able to design the array of bridges for this development.
• Solve permitting concerns by using timber piling throughout the wetlands and a freespan section across an environmentally protected trout stream.  No piling or equipment encroached upon the stream.  
• Construct the bridges on-site, which solved logistical problems. Delivering the material for the timber bridges through the steep, mountainous terrain did not pose the problem that delivery of prefabricated steel or concrete structures did. YBC’s deck level construction method allowed YBC to stay in compliance with permitting regulations, which only allowed foot traffic in the wetlands.
• Decrease turnaround time with YBC’s flexible scheduling and the use of timber. For this project, YBC was able to design and construct the timber bridges in 4-6 months less time than the originally proposed steel and concrete structures.

End result
Beyond the aesthetic, environmental, logistical and time objectives that YBC was able to solve, YBC’s price was 20% less than the steel and concrete crossings. According to Cyndi Godwin, Project Manager for Big Canoe, these bridges are “very fitting to the environment of Big Canoe.” The York Timber Bridges have created noticeable warmth in the community with the feeling that only comes from crossing a Timber Vehicular Bridge.

The project also created an unexpected benefit: The largest of the timber bridges built on site earned the prestigious “Award of Merit” as one of America’s Best Timber Bridges, one of only 50 bridges nationwide to ever receive this honor. This bridge won this honor for its innovation and execution in the design and construction of timber bridges. SLDT