Page 105 - Mapping the Nation: Taking Climate Action

Coastal Flooding Coastal flooding is becoming more frequent along the US coastline. Every site measured by NOAA has shown an increase in coastal flooding since the 1950s. The rate of increase is greatest along the East and Gulf Coasts. NOAA has confirmed that the places that flood the most are experiencing the highest sea level rise. With the rise of sea levels, low-lying areas are flooding more frequently, shorelines are eroding, and saltwater is fouling estuaries and nearby groundwater. The higher sea level also makes coastal infrastructure more vulnerable to the damage of increasingly extreme storms. Cities such as Norfolk, Virginia, which is served by the Hampton Roads Sanitation District (HRSD), are experiencing increased occurrences of flooding at high tide. Scientists call these events "nuisance floods" or "sunny-day flooding." The number of these floods has doubled since 2000. Although they may seem minor, they cause inconvenient road closures and storm drain issues and degrade HRSD's infrastructure. To take a proactive stance against increased flooding, HRSD is returning water to its aquifer to slow or halt sand settling, known as subsidence. GIS is instrumental in creating a digital twin of HRSD's infrastructure to monitor it in real time to make operations on the network and to ensure the aquifer recharge project progresses smoothly. In Cape Cod, famous for its fishing villages and summer vacationers, shorelines are slipping away. The Cape also forms one of the world's largest barrier islands, protecting the rest of the Massachusetts shore from violent northeaster storms. The Cape Cod Commission, formed in the 1980s, works to protect the peninsula's uniqueness and quality of life. With the assistance of NOAA's Regional Coastal Resilience Grant program, the commission launched the Resilient Cape Cod project. To start, it researched various coastline preservation strategies that have been developed around the world. It developed the Cape Cod Coastal Planner, an interactive, online app residents can use to visualize the local impact of sea level rise and erosion, along with different mitigation approaches to guide each community's resilience efforts. The San Francisco Estuary Institute took a similar approach of inventorying vulnerable places, cataloging strategies, and showing where similar places could apply the same strategies around San Francisco Bay. The San Francisco Bay Shoreline Adaptation Atlas serves as a science-based framework that takes advantage of natural processes for developing adaptation strategies specific to the area's diverse shoreline. Without proper preparation, communities face millions of dollars in infrastructure damage, displacement, and property loss. GIS provides a means to proactively map vulnerabilities and test solutions that have worked elsewhere. Modeling the processes at risk helps tackle the bigger question of how to improve climate resilience while maintaining functional ecological and hydrologic systems. Although sea level rise is increasing, we have data to support informed adaptation and coastal resilience measures. The more we collaborate, the better prepared everyone will be for the changes that are yet to come. 104