Introduction

High-quality elevation data for Utah inform decision making to improve the State’s economy. Light detection and ranging (lidar) data are used to support infrastructure planning and management, assess natural resources, and improve resiliency to hazards. The expanding availability of current and more accurate lidar data helps to better support natural resource conservation, wildfire risk management, geologic hazard investigation and mitigation, flood risk management, water supply planning, and urban planning and development. Critical applications that meet the State’s management needs depend on lidar data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features.

The 3D Elevation Program (3DEP; refer to sidebar) is managed by the U.S. Geological Survey (USGS) in partnership with Federal, State, Tribal, U.S. territorial, and local agencies to acquire consistent lidar coverage at quality level 2 or better (table 1) to meet the many needs of the Nation and Utah. The status of available and in-progress 3DEP baseline lidar data in Utah is shown in figure 1. 3DEP baseline lidar data include quality level 2 or better, 1-meter or better digital elevation models, and lidar point clouds, and must meet the Lidar Base Specification version 1.2 (https://www.usgs.gov/3dep/lidarspec) or newer requirements. The National Enhanced Elevation Assessment (Dewberry, 2012) identified user requirements and conservatively estimated that availability of lidar data would result in at least $8.70 million in new benefits annually to the State. The top 10 Utah business uses for 3D elevation data, which are based on the estimated annual conservative benefits of 3DEP, are shown in table 2.

Status of 3DEP in Utah

The State of Utah is second in the Nation for its percentage of federally owned land at 64 percent. Funding and collection of lidar has been a collaborative effort between various Federal (80 percent) and non-Federal (20 percent) partners. The Utah Geospatial Resource Center (UGRC) provides a wide range of geographic information system (GIS) and other geospatial support services. UGRC strives to ensure a high level of coordination among Utah GIS users and effective, efficient use of GIS resources. UGRC coordination has played a significant role in the completion of lidar coverage.

Since 2022, six partner agencies have contributed to three large projects with a total value over $6 million. These projects, along with 3DEP acquisitions by federal partners such as Federal Emergency Management Agency, U.S. Forest Service, U.S. Fish and Wildlife, Natural Resources Conservation Service, and USGS, have achieved completion of statewide 3DEP baseline lidar coverage in 2024. Next steps for the State include higher resolution (quality level 1) data in certain areas, maintaining quality level 2 coverage across Utah, and improving the quality and density of hydrography data based on lidar data.

Flood Risk Management

A significant percentage of Utah’s population lives in areas susceptible to flash flooding, but much of this flood risk is not identified, and this is especially true along intermittent or ephemeral streams. As a result, it is becoming increasingly important to map flood risk accurately to reduce costs and save human lives. High-quality elevation data can allow Utah’s Risk MAP Program to map flood risk areas not yet identified and revise current outdated flood risk information to better define the risk. Local and Tribal governments use lidar data as a tool for development planning and flood mitigation efforts.

Natural Resource Conservation

The Utah Department of Natural Resources; the U.S. Department of Agriculture (USDA), Forest Service; and the USDA, Natural Resources Conservation Service, all use elevation data for natural resource management applications including wildfire management, vegetation management, conservation engineering, soils and wetlands mapping and characterization, riverine ecosystem management, modeling of biological and ecological systems, erosion control (fig. 2), and recreation.

The economic significance of a broad range of activities in and around the Great Salt Lake is over $1.3 billion annually (Great Salt Lake Advisory Council, 2021, p. 3). Uses of the lake’s resources include brine shrimp harvesting, salt and mineral extraction, recreational activities, and wildlife habitat conservation. As the lake level fluctuates due to climate change and reduced water availability, understanding the changing shoreline and water volume using topographic and bathymetric lidar can inform decision making regarding this unique feature and the threats it faces.

Geologic Resource Assessment and Hazard Mitigation

With a wide range of geologic resources and hazards in the State, the Utah Geological Survey utilizes lidar for applications including geologic mapping and analysis, karst mapping, aquifer recharge, and geothermal energy resource development potential. Lidar is also used for identification of hazards such as landslides, debris flows, and faults, and as an aid in mitigating and responding to geologic hazards.