Resilience Scanner

LiDAR Elevation Data System for Sea-Level Rise Vulnerability Mapping

Solution Overview

Broward County coordinates with agency partners to ensure the coordinated acquisition of, access to, and informed use of LiDAR and other high-resolution elevation data for resiliency and adaptation planning, studies, stormwater modeling, asset management, and other purposes.[1] The County updated its LiDAR database with the 2018 USGS data set and continues to partner with municipal, state, and federal agencies to collect and maintain LiDAR data refinements for countywide planning.[1] This elevation data system enables improved analysis and mapping capabilities for identifying areas vulnerable to sea-level rise by utilizing the most recent LiDAR data.[1]

Technical Components

The project specifications were designed to meet or exceed USGS Lidar Base Specifications for Quality Level 1 Lidar at 8 pulses per square meter, with all flights planned to reach an average aggregate nominal pulse density of 10 pulses per square meter and an average aggregate nominal pulse spacing not to exceed 0.35 meters.[3] Dewberry deployed Leica Geosystems' linear-mode sensors, TerrainMappers, and ALS80s, along with Riegl VQ1560 and VQ1560i sensors for the Florida peninsula lidar project.[3] The lidar point cloud data includes classified ground data, building rooftops, overpasses and bridges, a hydrologically flattened digital terrain model, 3D breaklines, and associated metadata.[3] Within Fort Lauderdale specifically, a vehicle traveled throughout City streets, as well as along County and State roads within City limits, to capture data with a focus on street curbs, drainage swales, alleyways, and sidewalks using street level imagery and LiDAR elevation survey technology.[4] Broward County uses LiDAR elevation data in the development of land-use policies and modeling.[1]

Implementation Details

The Florida Division of Emergency Management, Florida Department of Transportation, Florida Department of Environmental Protection, and five Florida Water Management Districts worked in cooperation with the U.S. Geological Survey to maintain and update high-resolution elevation data through a $22 million lidar project covering the Florida peninsula.[3] The Florida Legislature appropriated $15 million in funds to FDEM, which entered into a joint funding agreement with USGS to match funds under the USGS Supplemental for Hurricane Irma totaling $7.6 million to acquire quality level 1 specification lidar data for roughly 35,000 square miles of the Florida peninsula.[3] The estimated cost for quality level 2 lidar completion in Florida is $0.88 million with a payback period of 0.08 year.[2] Broward County completed a Seawall Modeling Study in August 2018, prepared by Cummins Cederberg Coastal & Marine Engineering.[5] The information gained from the Fort Lauderdale LiDAR assessment is used to guide operations and maintenance activities and help the City plan for future capital improvement projects.[4]

Benefits and Impacts

The National Enhanced Elevation Assessment conservatively estimated that availability of lidar data would result in at least $10.88 million in new benefits annually to the State of Florida.[2] The 2017 Florida Statewide Lidar Assessment indicated that the state would realize a net benefit of more than $20 million per year for Quality Level 1 topographic lidar acquired every two to three years.[3] The Florida Statewide Lidar Assessment, conducted in 2017, exceeded the NEEA-identified benefits by almost $10 million, reporting at least $20 million in new benefits annually to the State with a need for topographic lidar coverage at quality level 1.[2]

Climate Adaptation Relevance

This elevation data system improves analysis and mapping capabilities for identifying areas of the County vulnerable to sea-level rise by utilizing the most recent LiDAR data.[1] The approach supports updating maps of potential impacts of sea-level rise to the natural and built environments at two and 3.3-foot levels, with this information considered in long-term planning.[1] The high-resolution elevation data enables stormwater modeling and asset management critical for addressing coastal flooding and precipitation-related hazards.[1]

Business Analysis

The estimated cost for quality level 2 lidar completion in Florida demonstrates a rapid payback period of 0.08 year against expected annual benefits of $10.88 million.[2] The 2017 Florida Statewide Lidar Assessment indicated that the state would realize a net benefit of more than $20 million per year for Quality Level 1 topographic lidar acquired every two to three years, establishing a strong financial case for recurring data acquisition.[3] The Florida Legislature's appropriation of $15 million in funds to FDEM, combined with USGS matching funds totaling $7.6 million under the USGS Supplemental for Hurricane Irma, demonstrates a public-sector joint funding model for large-scale elevation data acquisition.[3] This multi-agency partnership approach, involving state emergency management, transportation, environmental protection agencies, and water management districts working cooperatively with federal geological survey resources, represents a collaborative financing mechanism for maintaining critical climate adaptation infrastructure data.[3]

[1]: Broward County Climate Change Action Plan [2]: Florida Statewide Lidar Assessment [3]: Florida Peninsula Lidar Project [4]: Fort Lauderdale LiDAR Assessment [5]: Broward County Seawall Modeling Study

Sources