Susceptibility Index Designed to Safeguard Public Health
What would be the most pressing public health challenges in Charleston if a Category 2 hurricane were to trudge slowly along the South Carolina coast?
Lessons from recent storms make it clear: Flooding would be a major problem. So that’s what utility managers, hospital leaders, and municipal planners focused on recently when they gathered in Charleston to test a new tool developed to help understand public health risks from natural disasters.
A grant from the National Oceanic and Atmospheric Administration’s Coastal and Ocean Climate Applications program is funding work on the tool, called a susceptibility index, as part of a broad guidebook on the issue. Researchers and graduate students from the S.C. Sea Grant Consortium, University of South Carolina, East Carolina University, North Carolina State University, and Saint Louis University examined the relationships between water infrastructure and public health in two coastal communities: Charleston, South Carolina and Morehead City, North Carolina.
With some in Charleston still drying out a week after Tropical Storm Irma’s 4-foot storm surge hit, local officials at the tabletop exercise compared their recent challenges with the potential problems raised by the fictional 2030 Hurricane Liz created for the engagement.
Participants at a tabletop exercise tested a susceptibility index designed to help determine how prepared communities are for natural disasters. Photo by Joey Holleman, S.C. Sea Grant Consortium.
Sea-level rise could mean tides are 1.5 feet higher than in 2017. Add a couple more feet if the storm coincides with a lunar cycle King Tide. And the storm model put together by Tom Crawford, a geography professor at Virginia Tech, incorporated a prolonged rain event preceding the storm. Sea-level rise, rainfall from the preceding storm, King Tides, and storm surge added 6 to 12 feet of inundation along the coast and on tidal waterways well inland.
Crawford used map overlays to show which critical health facilities would be inundated in the “Hurricane Liz” scenario. Using those maps as a guide, the various groups at the meeting then tested methods for gauging the susceptibility of infrastructure to inundation and damage.
The process includes questions about current readiness of utilities, health-care facilities, and municipal governments. Are sewage pump stations designed to keep working when inundated? Do hospitals have plans for getting workers to their facilities if the buildings are surrounded by water? Are municipalities equipped to spray for mosquitoes when the roads are still flooded days after a storm?
Based on answers to the questions, the susceptibility index provides a rating on a 1 to 5 scale and a list of best management practices that could help them improve their score. However, participants in the exercise felt the real value is that the process prompts self-evaluation.
“These questions are a lot to move through, but they’re interesting to think about,” said Connie Banegas, director of asset management for the Charleston Water System.
“This would be useful not just as an exercise but as a tool for planning,” said John Simkovich, preparedness coordinator with the S.C. Hospital Association.
The participants suggested tweaks to some of the questions on the survey. Those suggestions will be incorporated into a final product — a guidebook and susceptibility index that can be adapted for various communities and public health concerns.