The future is unknowable, especially when it comes to extreme weather.
But with the help of innovative flood modeling and systems engineering approaches used by the University of Georgia’s Institute for Resilient Infrastructure Systems (IRIS), the campus’ Risk and Resiliency Division (RRD) can make more informed decisions about where to shore up defenses against flooding.
The University of Georgia’s Athens campus is located at the nexus of four major waterways: North Oconee River, Tanyard Creek, Trail Creek and Lily Branch, all of which intertwine around, through, and in some places, under campus.
“When the UGA campus takes a ‘shower,’ there’s a lot of ‘plumbing’, both visible and out of sight, that carries stormwater to the Oconee River. It’s important to understand how people and the built environment are likely to be affected by extreme rainfall, and to keep improving flood protection. Creeks, floodplains and underground pipes all have to work together as a system to avoid damage,” said Brian Bledsoe, co-Director of the Institute for Resilient Infrastructure Systems and professor in the College of Engineering.
While development on top of and around streams and rivers is far from uncommon, it can cause issues down the line—leading to increased risk of flooding that can put the built landscape and people in it at risk.
This is where the Risk and Resiliency Division comes in, with its mission to strengthen the University’s ability to anticipate, prepare for, respond to and recover from emergencies and disasters. The study began when Adam Fouche, newly appointed associate vice president of the RRD, approached IRIS researchers about conducting a study to assess areas of potential flooding.
“Effective risk management starts with understanding our vulnerabilities,” said Fouche of the project. “This partnership with IRIS provides critical data and analysis to help us better assess flood hazards across campus, prioritize mitigation strategies, and strengthen UGA’s long-term resilience.”
While flood models for campus exist from the Federal Emergency Management Agency (FEMA) Flood Insurance Study program, these models largely fail to account for changing precipitation and land use conditions.
For example, research by IRIS affiliate and Director of UGA’s Atmospheric Science Program, Marshall Shepherd, indicates that heavy rainfall from summer thunderstorms is getting more intense. Similarly, as more and more areas are developed with impermeable surfaces (such as concrete), rainwater will be unable to soak into the ground, worsening flood conditions.
IRIS researchers created models that build on FEMA’s maps, using scientifically vetted methods to produce enhanced maps that more accurately depict flood risks on campus.
“These modeling results were coupled with watershed-scale, system analysis strategies to better understand why an area may be more prone to flooding due to upstream hydrology, along with the identification of high-level strategies to begin addressing flood risks,” said Zak Ruehman, Director of Engineering Services for the Institute for Resilient Infrastructure Systems.
They also developed flood forecasting measures to provide campus with a foundation for predicting when flooding may occur based on rainfall predictions. Researchers noted that floods as small as the 5-year flood (which has a 20% chance of happening in any given year) were likely to cause flooding at some of the most vulnerable locations across campus.
This study is a first step in a broader effort to help bolster campus resilience. Next up, the researchers hope to understand the extent of the risk from Tanyard Creek, which runs through the heart of campus, adjacent to Bolton Dining Commons and beneath Sanford Stadium—and poses a flood risk to the high-traffic area of Lumpkin Street and surrounding parking areas and buildings.
They will do this through focused study of the watershed through field surveys, robust hydrologic and hydraulic modeling techniques and the installation of a permanent flood gage that will display real-time water level data through a dashboard. This flood gage, coupled with the installation of other sensors throughout Tanyard Creek and its tributaries, will help to calibrate models and identify where major sources of water are coming from.
“Our hope is that the findings from Phase 1 will inform how and where to strategically focus future efforts and allocate resources where they are needed most to improve flood resilience on campus,” said Ruehman of the project. “When it comes to the effective management of our infrastructure assets, it’s all about working to shift from a reactive, ‘run-to-failure’ mode of operation to a predictive, ‘address-failures-before-they-happen’ strategy, in the most resource efficient manner possible. This is going to be the driving theme as we move into future phases.”
The next phase also includes an assessment of how natural and conventional flood solutions can be combined to help ameliorate these risks–another area that IRIS specializes in.
Natural flood solutions use the power of nature to help slow and divert water flow to a given area, while conventional solutions can include things like upsizing stormwater detention systems to reduce peak flows and upscaling roadway crossing structures such as culverts to minimize the backup of water. Together, they have the power to help reshape flood risk.
“Our engineering analysis will help identify a mix of conventional and nature-based measures that better protect UGA’s people and infrastructure while at the same time making campus more pleasant and beautiful,” Bledsoe said of the project.
Together, IRIS and the Risk and Resiliency Division are teaming up for a more resilient UGA campus.
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IRIS is an interdisciplinary UGA institute housed in the College of Engineering, and is a national leader in the resilience sphere, where it helps communities and businesses assess the natural hazards that could impact them, develop plans using natural and conventional infrastructure solutions that help lessen risks, and ultimately implement solutions.