Florida Sea-level Rise Sketch Planning Tool for Transportation
The University of Florida (UF) developed a geographic information system (GIS)-based “sketch planning tool” to help transportation planners in Florida identify transportation infrastructure potentially vulnerable to projected sea-level rise. The sketch planning tool offers a mapping function to visualize areas that will be affected by different sea-level rise scenarios based upon surface elevations and the location of infrastructure. The tool is also customizable for experienced users to allow them to create more spatially refined inundation surfaces. The sketch planning tool is designed to support decision-making at the statewide and regional (FDOT district) scale by indicating potentially vulnerable infrastructure, which can be prioritized for further analysis.
The UF GeoPlan Center developed the sketch-planning tool in a first phase of the project, and later refined and tested its functions in a second research phase. The sketch-planning tool utilizes multiple data inputs to model inundation surfaces (i.e., sea-level scenarios) and identify potentially vulnerable assets. The tool’s inputs include: sea-level projection curves developed from the Army Corps of Engineers Engineering Circular 1165-2-12; tide station data from fourteen National Oceanic and Atmospheric Administration (NOAA) tide stations in Florida; digital elevation data including LIDAR-derived data; and three inventories of transportation assets including roadways, railways, airports and seaports. The team created a statewide digital elevation model (DEM) with 5-meter resolution. One limitation of the DEM data initially used was the lack of bridge elevation information.
From these data sources, a single inundation layer can be created by selecting a sea-level change projection curve (low, intermediate, or high), a decade between 2040 and 2100, a tidal datum, and a geographic scale (statewide or single FDOT district). These options are combined with information from the statewide DEM to produce the inundation surface. The GeoPlan team also enhanced the inundation surfaces by including a filter showing hydroconnectivity, which helps users avoid identifying inland areas as inundated even though they are not hydrologically connected (directly or indirectly) to the ocean. Users can map or download the data for specific inundation surfaces and overlay with some or all of the data about transportation assets from the inventories included in the tool. Using the outputs from the sketch-planning tool, users can identify potentially vulnerable transportation infrastructure assets.
The sketch-planning tool includes three separate functions that present the data in different formats for users of different levels of expertise with GIS software. These functions include:
- A web-based map viewer, which allows users to visualize and identify areas and infrastructure that could potentially be affected by sea-level rise over time using a “time slider” function. From the map viewer, users can also create summary reports of potentially affected infrastructure.
- Modeled data layers, including inundation surfaces and corresponding infrastructure layers. These can be downloaded but require GIS software to view. Users can also overlay these data layers with additional local infrastructure data to create more refined models.
- A Sea Level Change Inundation Surface Calculator, an ArcGIS tool that allows users to customize the inundation surface by using a higher-resolution DEM. By default, the sketch- planning tool uses a DEM with 5-meter horizontal resolution, but this inundation surface calculator allows users to input a DEM of any resolution, potentially yielding a more spatially refined inundation surface. This third function of the sketch planning tool requires the highest level of GIS technical expertise to use.
The sketch-planning tool was designed initially for regional or statewide use only, as the DEM resolution built into the tool did not provide information such as roadway and bridge elevations, or the locations of ditches, levees, etc. Data outputs from the sketch-planning tool can be incorporated into existing FDOT project development processes if desired by FDOT. After the first phase of research, GeoPlan identified benefits, limitations, and possible enhancements for future updates to the tool, such as including storm surge models, floodplain and groundwater mapping to identify combined effects with sea-level rise on infrastructure vulnerabilities.
In the second phase of the research project, the GeoPlan Center worked with two MPOs to evaluate the usefulness of the sketch-planning tool for analysis at the MPO scale, and to improve the tool’s effectiveness for decision support. The GeoPlan team partnered with the Hillsborough MPO and the Broward MPO, both of which received grants through FHWA’s Climate Change Resilience Pilot Program to assess infrastructure vulnerability (with Broward MPO managing the pilot project grant on behalf of a larger four-county region in Southeast Florida). These partnerships allowed the GeoPlan team to test the tool in real-time in the context of a vulnerability assessment for transportation infrastructure, and to identify data gaps and technical challenges that could be addressed with future revisions to the tool. The GeoPlan Center further tested the tool through partnerships with the City of Satellite Beach and Monroe County, both of which were engaged in separate adaptation planning efforts.
During phase two, GeoPlan first tested methods to enhance data inputs, including by developing more accurate information for the elevation of bridges. GeoPlan created a separate data layer for bridge deck elevations using LIDAR data, and tested this new functionality in the five pilot counties. GeoPlan also tested the effectiveness of the existing DEM, as compared against two higher-resolution DEMs (2-meter and 3-meter) derived from LIDAR data. They found that the differences in inundation area between the 3 DEMs tested were not substantial, and the existing DEM provides a good balance between accuracy of inundation mapping and file size/processing time. They also evaluated the adequacy of the existing transportation data inputs for smaller (MPO) scale analysis, using the MPO partners to test the tool. GeoPlan found that additional data layers were not needed to analyze transportation impacts at the MPO scale; rather, bridge elevation data and any updates to the existing transportation inventories were more helpful.
GeoPlan also researched and tested storm surge models and methods (including FEMA’s Hazus-MH, SLOSH, and FHWA’s HEC 25, Vol. 2) to begin investigating methods for assessing sea-level rise effects on storm surge. For coastal flood hazard areas, GeoPlan found that a tiered approach could be taken: first, incorporating transportation infrastructure at risk to current flood hazards (best available 100-year floodplain) into the sketch planning tool, and next, using the 500-year floodplain as a proxy to evaluate future flood risks. For more refined flood hazard information and for modeling the effects of sea-level rise on coastal storm surge, GeoPlan recommends further investigation of several models.
The MPOs were able to use the sketch planning tool during their adaptation pilot projects to help assess risks to transportation infrastructure in their counties from sea-level rise. Both MPOs and the other partnering jurisdictions (Satellite Beach and Monroe County) developed recommendations for improving the tool. The GeoPlan Center has addressed some of these recommendations already in updates to the tool (such as the addition of bridge elevation data, and other enhancements to improve ease of use and functionality), and others may be explored in future research (such as incorporating floodplains and storm surge data).
University of Florida developed the sketch-planning tool with funding from FDOT. It was developed as a follow-on to a previous study, also funded by FDOT but undertaken by Florida Atlantic University (FAU), which assessed different methods for projecting sea-level rise in Florida and made recommendations for how FDOT should assess vulnerability of its infrastructure. University of Florida developed accompanying reports documenting the research and development of the sketch planning tool through the first and second phase of this project.
This Adaptation Clearinghouse entry was prepared with support from the Federal Highway Administration. This entry was last updated on January 28, 2016.
Publication Date: October 2015
- University of Florida
- Florida Department of Transportation
- Mapping tool
- Tool (general)