A planning tool for preliminary assessment of transportation infrastructure vulnerable to current and future flooding


Project Background

The Sea Level Scenario Sketch Planning Tool has been completed over three phases and multiple years (2012 – 2017). The GeoPlan Center has recently finished Phase 3 of this work, culminating in updated SLR models of inundation and an updated Map Viewer.

In Phase 1 (2012-2013), researchers from the University of Florida (UF) GeoPlan Center developed the Florida Sea Level Scenario Sketch Planning Tool (SLS Sketch Planning Tool) to facilitate identification of transportation infrastructure potentially at risk from projected sea level changes.  The purpose of the tool was to visualize various sea level scenarios at future time periods to inform transportation planners and highlight infrastructure for potential avoidance, minimization, or mitigation.   The Phase 1 work built upon the research completed under Florida Department of Transportation (FDOT) contract BDK79 977-01, Development of a Methodology for the Assessment of Sea Level Rise Impacts on Florida’s Transportation Modes and Infrastructure (Florida Atlantic University, 2012).

US Army Corps of Engineers (USACE) sea level change projection methodology, as outlined in Engineering Circular EC 1165-2-212, was used in Phase 1 to generate statewide and regional SLR projections (“low/ historic”, “intermediate”, and “high” projections) in 10-year increments from 2040 through 2100. The benefits of this methodology include the use of local data to generate relative SLR projections, projections for multiple scenarios, and the ability to revise the calculations based on the latest available guidance and trends.

In Phase 2 (2013-2015), the GeoPlan Center and FDOT Office of Policy Planning worked with two Metropolitan Regional Planning Organizations (MPOs) to test the tool’s usefulness for planning at the regional scale.  Both MPOs were awarded grants through the Federal Highway Administration (FHWA)’s Climate Change Resilience Pilot Program, which has funded partners to assess infrastructure vulnerability to the impacts of sea level changes and extreme weather events, determine adaptation options, and improve resiliency of infrastructure. This opportunity allowed for “real-world” testing of the SLS Sketch Planning Tool with partners who could benefit from the tools, while providing feedback on usability enhancements.

In Phase 3, improvements and updates were made to the Sketch Planning Tool based on recommendations from Phase 2 and incorporation of the latest available data and science.  Major updates completed in this phase of work included: re-run of the SLR models of inundation and affected infrastructure using updated input data and corrected bridge elevation data; development and deployment of a new, modern web map viewer for data visualization; update of the GIS calculator tool; addition of current flood risk.

In this phase, SLR scenarios were re-mapped by county, utilizing local tide station data, the best available elevation data, and five SLR projections from NOAA (2012) and USACE (2013).  Updated transportation data was analyzed using the newly mapped SLR scenarios. Finally, segment-level analyses were completed, calculating amount and percentage of impact to transportation assets under each SLR scenario.

As sea level projections and tidal datums are modified over time, horizon year, and place, the ability to have a framework of tools that are customizable (based on the latest data inputs and projections) will facilitate the revision and reassessment of potentially impacted areas and related infrastructure. In addition, as higher resolution data inputs become available, the analysis can change from statewide and regional to more local in scale. The tools developed in this project support higher resolution data inputs and facilitate reproduction of the data outputs (inundation surfaces and affected transportation infrastructure layers).

Project Tools: Sea Level Scenario Sketch Planning Tool

The Sea Level Scenario Sketch Planning Tool includes (1) a map viewer, (2) output modeled GIS data layers (inundation surfaces and affected infrastructure), and (3) an ArcGIS tool for creating custom inundation surfaces.

(1)Map Viewer

The map viewer allows for visualization and identification of potentially inundated areas and affected transportation infrastructure due to sea level rise and current flood risk. The map displays SLR scenarios for five SLR projections and seven time periods. SLR projections were mapped by county, using local tide station data, and then the individual counties were merged into a seamless statewide mosaic.

SLR Projections Mapped:

C1 = USACE Low (2013)/ NOAA Low (2012)
C2 = USACE Intermediate (2013) / NOAA Intermediate Low (2012)
C3 = NOAA Intermediate High (2012)
C4 = USACE High (2013)
C5 = NOAA High (2012)

The map viewer interface was developed using ESRI’s ArcGIS for Javascript.

(2) GIS Data Layers:

The output modeled GIS data layers include the SLR inundation surfaces and corresponding affected infrastructure layers. These output data layers are displayed in the map viewer. SLR inundation surfaces are available by county (36 coastal counties), for seven decades (2040 – 2100), five SLR projections (USACE and NOAA), and two tidal datums: MSL and MHHW. The SLR inundation surfaces are available as vector or raster feature classes in a file geodatabase, and the infrastructure layers are available as vector feature classes.

All data layers require ArcGIS software to view and moderate knowledge of GIS and mapping. Data layers can be overlaid with local infrastructure data and other data layers of local interest. These output data layers are designed to be integrated into existing FDOT decision support systems and assist state and regional transportation planning and programming activities (e.g. Efficient Transportation Decision Making, Long Range Transportation Plan).

(3) SLR Inundation Surface Calculator

The Sea Level Rise Inundation Surface Calculator is an ArcGIS tool for creating custom inundation surfaces. The calculator allows users to choose one of the three USACE projective curves (low/ intermediate/ high), a decade (2040-2100), a tide station, and a Digital Elevation Model (DEM) layer. ArcGIS software and intermediate/ advanced technical and/or GIS expertise is needed to use this tool. With this tool, it is possible for a user to create a more refined inundation surface using a DEM with a higher horizontal resolution (than the 5-meter DEM used).