Project Overview
Garnsey Range is an important training asset for the Army and Fort Moore and continued access to the area is critical to the military mission. The roadway crossing at Shell Creek within Garnsey Range has historically utilized traditional corrugated metal pipes to convey flow through the channel. This solution has resulted in multiple structural failures that have led to blowouts, rendering the crossing impassable for standard range operations. These traditional solutions to stream crossing design also pose a barrier to aquatic organisms that disrupt connectivity throughout the stream’s watershed.
We performed a preliminary analysis of this crossing and utilized an Engineering with Nature approach to develop a design of a multi-objective stream crossing structure. The goal was to provide a robust, climate-resilient design that not only provides hydraulic capacity to safely pass flows attributed to changes in future land use and rainfall, but also supports aquatic organism passage and floodplain connectivity.

Meet the Team
The engineering expertise for this project was led by the Institute for Resilient Infrastructure Systems, with input from departments and institutes across the University of Georgia. The project is also supported by Daniel Sebastian, graduate student at Columbus State University, and IRIS communications team Sarah Buckleitner and Olivia Allen.


Brian Bledsoe, Ph.D., P.E. Director of IRIS, College of Engineering

Zak Ruehman, P.E. Senior Resilience Engineer, IRIS

Matthew Schudtz, J.D. Law and Policy Fellow, IRIS

Kevin Samples Geographic Information System Specialist, IRIS

James Shelton, Ph.D. Associate Professor, Warnell School of Forestry and Natural Resources

Jon Calabria, Ph.D., P.L.A. Professor, College of Environment & Design

Haley Selsor, E.I.T. Research Professional, IRIS

John Montoya, E.I.T. Research Assistant, IRIS

Daniel Wyatt Defense Community Resiliency Professional, CVIOG

Alejandra Gomez PhD Student, IRIS

Scott Luis, J.D. Research Professional, Carl Vinson Institute of Government
Project elements

The Problem
In-depth hydrologic and hydraulic analyses indicated that the most recent crossing solution, an 84-inch corrugated metal pipe, experienced significant roadway overtopping during the 25-year storm event. Further analysis indicated that a three-sided structure with a 20-foot span and 10-foot rise has the capacity to convey the 100-year storm event associated with an existing land use and existing rainfall pattern scenario; however, it does not have the capacity to pass flows attributed to future rainfall patterns or land use changes.
the FINDINGS
ThisA 65-foot clear span bridge alternative was investigated and found to provide the necessary capacity to pass all 100-year storm event flows for all rainfall pattern and land use change scenarios, while also providing 1-ft of freeboard underneath the low chord of the bridge.
The proposed three-sided culvert improves aquatic organism passage, but still hinders floodplain connectivity and constricts the natural channel. The bridge alternative completely spans the bankfull width of Shell Creek, allowing for aquatic organism passage and the ability for the channel to self-adjust, potentially resulting in floodplain reconnection.
The clear span bridge is recommended as a cost-effective, climate-ready, stream crossing structure that provides adequate hydraulic capacity to account for future land use change and climate scenarios while enhancing aquatic organism passage and floodplain connectivity.

Additional Resources to Explore
Full report coming soon!