User needs in hazard mitigation planning: Examples from coastal South Carolina

The state of South Carolina codified progressive coastal zone management policies in the landmark Beachfront Management Act of 1988 (S.C. Code Ann. § 48-39-250 et seq.) and has long assisted with the development of state-mandated Local Comprehensive Beachfront Management Plans. However, it was not until the passage of Hurricane Joaquin in 2015, and the associated historic flooding, that the state of South Carolina has shown a genuine commitment to funding coastal hazard mitigation efforts. Since 2015, South Carolina has appropriated a total of $46 million in beach nourishment efforts statewide (compared to nearly $0 in the past), the Governor appointed a Floodwater Commission in 2018, and local communities have developed numerous sea level rise adaptation strategies with state support. Coastal municipalities are investing in major drainage and infrastructure improvements to improve flood protection. The City of Charleston made a $235 million capital investment in drainage improvements (tunnels, pumps) and transportation improvements (roads, seawalls) between 1990 and 2020.

This presentation will highlight recent examples of successful collaborations between managers and researchers, where user needs have directly informed scientific approaches and the resultant products. Planners have engaged community leaders, residents, and other stakeholders in participatory exercises to prioritize coastal hazard mitigation challenges. Most of these challenges relate to water level changes due to sea level rise and extreme event impacts. To address these challenges, communities are developing management and adaptation strategies for drainage infrastructure, septic vulnerability, marsh and dune management, and transportation routes. Some federal tools, such as NOAA’s Sea Level Rise Viewer, have been leveraged in South Carolina’s hazard mitigation planning efforts. More often, coastal communities collaborate with scientists on high-resolution, site specific flood maps to visualize the impacts and thresholds of various elevated water level scenarios on critical infrastructure. This presentation will summarize the science and tools being used by coastal communities and opportunities to better communicate coastal hazard observational and modeling research to meet user needs.