Topographic and bathymetric information provide the basis for equation inputs, such as water depth, beach slopes, and land elevations. These data are also valuable when creating numerical modeling domains to determine various coastal processes at a particular location. The following discussion focuses on evaluating and acquiring existing data for these purposes, but there are locations or projects that may require new data collection. In general, the entire Texas coastal region has had LiDAR data collected since 2007 that provide topographic coverage of high resolution, that would only need to be supplemented by local survey for design work. Bathymetry is much less recently or accurately collected along the Texas coast. Readily available bathymetry datasets would be sufficient for Level 1 or possibly Level 2 analyses, but for Level 2 analyses where water depths at or near the project site are critical for coastal design calculations and any Level 3 analysis, local bathymetric survey would be required to supplement the regional or statewide datasets.

In many cases, existing high-resolution datasets, such as LiDAR terrain or bathymetry data, will be readily available. When used in combination with site specific field surveys necessary for project design, they can provide the information necessary to understand historical trends of elevation changes in the project area, including in the surrounding submerged environment when bathymetric field survey is collected. In locations where LiDAR or other high-resolution elevation/bathymetric datasets already exist, the designer must determine whether and how the datasets can be used in the project. The following conditions should be considered: