BOONE – Monica Davis, an Appalachian State University graduate student, is spending her summer conducting flood mapping research on the Swannanoa River in Asheville. Many states can benefit from Davis’ research and be better prepared for future floods and disasters.
Monica Davis conducts flood mapping research with her mentor, Dr. Jeffrey Colby, an associate professor in Appalachian State University’s Department of Geography and Planning. (Appalachian photo by Marie Freeman)
Davis’ interest in flood mapping is rooted in her love of whitewater kayaking. Combining her interests of water levels and flooding with her studies in geography will help her to realize her dreams in emergency management.
About her research
In the Department of Geography and Planning, Davis is analyzing recent data taken from the Swannanoa River in Asheville in order to construct the most accurate representation of flood extent and depth, and to analyze the amount of damage caused by floods. She is building on previous research conducted by her mentor, Dr. Jeffrey Colby, an associate professor in the Department of Geography and Planning.
The goal of Davis’ research is to accurately depict the topography of the Swannanoa River by identifying the spatial resolution that is best for flood mapping, using Light Detection and Ranging (LiDAR) elevation data provided by the North Carolina Flood Mapping Program. LiDAR is similar to active SONAR; however, LiDAR uses laser pulses of light instead of sound. LiDAR also uses an airborne laser to retrieve data as it reflects off tops of trees, buildings and bare earth. In some states, flood mapping utilizes data retrieved 30 years ago or more, rendering a less accurate 3-D model of the land. Where the old method measured elevation every 10 or 30 meters, LiDAR technology allows for a measurement of four meters or less.
Why it matters
“Obviously, a four-meter spatial resolution is better than a 30-meter spatial resolution, but it’s more time consuming to obtain and process,” said Davis. “Our goal is to find the maximum spatial resolution, or range of spatial resolutions, for accurate flood mapping.”
For families and businesses surrounding the Swannanoa River, these few meters matter. Flood mapping determines their insurance policies based on the 100-year flood level, and inadequate data produces inaccurate flood insurance policies. Homes and businesses within the 100-year flood level pay higher insurance premiums, so it is important that the modeled flood level and boundary is accurate.
Furthermore, if a city is unprepared for a major flood, reservoirs may be forced to let go of water at an inappropriate time. “Having an emergency plan in place prior to a major flood event can decrease the overall effects of a devastating flood,” said Davis. “The City of Asheville learned its lesson during the disastrous floods of 2004 created by hurricanes Francis and Ivan. After these devastating floods, the City of Asheville created the Flood Damage Reduction Task Force charged with creating an emergency management plan which included a flood operations plan and emergency action plan for Burnette Reservoir. This plan allows the pre-release of water from the reservoir prior to a potentially large flood event deterring the contribution of excess water to an already flooded river.
In 1999, Hurricane Floyd sent a powerful message to the state of North Carolina when the storm generated 500-year flood levels. Catastrophic flooding persuaded state officials to acquire their own LiDAR data, bringing North Carolina flood maps up-to-date. Since then, only eight or nine states have completed their LiDAR aquisition and post-processing. Many of the country’s flood maps are still out-of-date.
Road to Appalachian
After graduating from Purdue University, Davis worked in the fields of forestry and horticulture for a couple of years. She decided a master’s degree was necessary to advance in her career and really make a difference. A culmination of Davis’ love for whitewater kayaking, her desire for higher education, and optimal timing led her to Appalachian.
“I was driving back from Charlotte when I saw a sticker on the back of a car that said Appalachian State University. They had a bunch of kayaks on top and I wanted to know what Appalachian was all about,” she said. Davis was looking for a master’s program in geography and planning at the time, and she was excited to learn that Appalachian offered just that.
“The faculty here are quite amazing. They have a good collaboration and fellowship with each other, and I thought that was crucial. At other universities I visited, the faculty all worked on their own research projects and it wasn’t a joint effort,” she said.
Davis, along with other geography graduate students, was able to attend a meeting of the N.C. Association of American Planners as well as a Southeastern Division of the Association of American Geographers meeting, courtesy of the Department of Geography and Planning.
“I like the fact that you can apply geographic knowledge, or the understanding of space and place, in any job,” said Davis. “It can be used in marketing, planning, engineering, and even medical sciences – geographical thought provides a different perspective when approaching a problem.” After graduation, Davis hopes to find a career in emergency management, pertaining to flood modeling or natural disasters.