Introduction

High-resolution elevation data for Texas inform decision making to improve the State’s economy. Existing elevation data coverage is used to improve resiliency to natural disasters, manage energy infrastructure, and assess natural resources. The expanding availability of current and more accurate elevation data helps better support natural resources conservation, agriculture and precision farming, flood risk management, infrastructure and construction management, geologic resource assessment and hazard mitigation, coastal zone management, and identification of features of interest or concern, such as archaeological and historic sites. Critical applications that meet the State’s management needs depend on light detection and ranging (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 Texas. The status of available and in-progress 3DEP baseline lidar data in Texas 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 $53.1 million in new benefits annually to the State. The top 10 Texas 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 Texas

The Texas Geographic Information Office (formerly Texas Natural Resources Information System), a division of the Texas Water Development Board (TWDB), acquires lidar data through the State-funded Strategic Mapping Program (StratMap), which partners with other State, local, and Federal agencies through the Strategic Mapping Program Contracts. Since 2009, 39 partner agencies have contributed to 40 projects with a total value of $19.6 million. These projects, along with 3DEP acquisitions by Federal partners such as the Federal Emergency Management Agency, the Natural Resources Conservation Service of the U.S. Department of Agriculture, and the USGS, achieved completion of statewide lidar coverage in 2020. Next steps for the State include obtaining higher resolution (quality level 1) data in certain areas, maintaining quality level 2 coverage across Texas, and improving the quality and density of hydrography data based on lidar data.

Water Supply and Quality

Texas is experiencing tremendous population growth, along with a recurring threat of severe drought. The mission of the TWDB is “to lead the State’s efforts in ensuring a secure water future for Texas” (Texas Water Development Board, 2023). Lidar data are used to help fulfill this mission as base data for reservoir flood-pool modeling, hydrodynamic modeling, reservoir capacity determinations, sedimentation studies, and determinations of freshwater inflow requirements.

Flood Risk Management

Texas experiences significant coastal and riverine flooding, such as the Blanco River flood (fig. 2) which killed 12 people and caused severe infrastructure damage. High-resolution lidar can be used to improve the accuracy of flood-plain mapping and hydrologic modeling, enabling flood planners to better identify area of high risk, which could lead to mitigating the costs of flood events and possibly saving lives.

Coastal Zone Management

As a frequent target of tropical storms, Texas coastal communities experience cycles of storm impact and recovery, costing billions of dollars. According to the National Oceanic and Atmospheric Administration, Office for Coastal Management, Hurricane Harvey in 2017 was the most significant tropical cyclone rainfall event ever recorded in U.S. history, both in scope and in peak rainfall amounts. The highest total rainfall reported from Harvey was 60.58 inches and the estimated total cost of the storm was $125 billion (Blake and Zelinsky, 2018, p. 6, 9) in losses. Lidar data are used by State, regional, and local governments to mitigate coastal storm threats, identify areas at risk, and improve Texas citizens’ resilience to storms.

Wildlife and Habitat Management

The Texas Parks and Wildlife Department and the U.S. Fish and Wildlife Service utilize high-resolution elevation data for modeling wildlife habitat, to accurately map ecosystems and natural resources in the State. This application of lidar data contributes to increased confidence in map accuracy (fig. 3) and program effectiveness, provides information for public applications such as state park usage, and leads to improved management of natural and cultural resources (Mueller and Sesnie, 2020).