Sea-level rise is going to impact cities around the globe, most drastically in coastal communities, many of which have been at risk for years.
One such example of this data-driven planning is occurring in Kauaʻi County, Hawaii, where officials passed legislation to regulate construction based on sea-level rise projections and established guidelines for development in areas prone to impacts of rising sea levels.
Alan Clinton, the county’s administrative planning officer, explained the passage of Bill No. 2879 called for consolidation of data into something easily digestible for use by the City Council, legislators and other stakeholders.
The county created the Sea Level Rise Constraint District Viewer using tools from Esri, specifically underlining the Experience Builder tool.
This tool uses data from a 2017 University of Hawaii (UH) report that offers individual depths associated with this hazard area, helping inform the elevation level needed for structures developed. It differs from the floodplain management program, which uses historic data, by using projected models to predict needs for future hazard conditions, showing what could be seen in the area dating up to the year 2100.
“So, this bill really showcases that we can use future conditions to inform a regulatory framework,” Clinton said.
Because the county had coastal engineers, scientists and land use attorneys vet the work, Clinton said leadership was supportive and the legislation was unanimously approved.
The county’s goal is to take this work further in the future to incorporate data from atmospheric and hydrological modeling. However, he noted that with sea-level rise, there is a global consensus on the basis for the data underlining the policy; for atmospheric and hydrological modeling, there is not yet consensus. The county is working with partners at UH and other scientists to determine what authoritative academic sources can be cited for this kind of regulatory framework.
He underlined that the legislation and platform the county created could be re-created for any other Hawaii counties in a matter of hours — and potentially in other parts of the country as well.
The city of Norfolk, Va., is another community facing major risks related to rising sea levels. As explained by City Council Member Andria McClellan, the region is ranked second only to New Orleans, La., in terms of flood risk related to coastal storms — with projections revealing a four- to five-foot rise by the year 2100, according to conservative estimates.
Through the implementation of cameras in the stormwater system, the city was able to determine that the system is at about 50 percent capacity because of the sea level and frequent nuisance flooding regularly impacts community members. As such, the city worked with FloodMapp to incorporate flood data into the mobility app Waze so drivers could reroute based on weather conditions.
The city also launched an interactive online tool, the Flood Risk Learning Center, that allows residents to input their address to visualize the impacts that storm conditions might have on their homes.
McClellan also noted that because floods are not restricted by jurisdictional boundaries, the city is also leveraging regional solutions, like a flood sensor program launched earlier this year. In addition, RISE, a resilience lab incubator funded through the Superstorm Sandy National Disaster Resilience Competition, has funded several regional initiatives related to infrastructure, mobility and flooding.
Notably, McClellan underlined that historically redlined neighborhoods are disproportionately affected by flooding as a result of infrastructure issues. As such, she argued that flood resilience funding and initiatives should be intentionally implemented with an equity lens not to exclude these neighborhoods.
Meanwhile, the city of Clearwater, Fla., is using technology to guide urban planning and development to help prepare the city for future sea-level rise.
The city launched a platform using Forerunner software earlier this year, which offers a visualization of the most stringent building requirements for base flood elevation to meet regulations.
This is especially helpful as the city has adopted a more stringent standard than the one given by the Federal Emergency Management Agency, explained by Sarah Kessler, environmental specialist for the city. The city uses the regulatory standard of the Pinellas County Sea Level Rise and Storm Surge Vulnerability Assessment.
The platform is primarily used by the city’s building department, which Kessler said is one of the few groups with access to the full version of the tool. However, anyone in the city can access the public-facing version, which offers necessary information for project planning.
Forerunner co-founder Susanna Pho said cities around the country are working to regulate floodplain development, explaining that the software extracts information on structures and then uses data from permitting documents to create a visualization with geospatial data.
Pho also noted discussions are in progress with the city to explore how theoretical scenarios or projects, such as the creation of a sea wall, could impact different parts of the city.
