2025 Lidar DEM (Hydro-flattened): San Francisco Bay - Delta Estuary, CA

Product: These are Digital Elevation Model (DEM) data for California as part of the required deliverables for the SanFrancisco_Baylands_Lidar project. Class 2 (ground) LiDAR points in conjunction with the hydro breaklines were used to create a 1 foot hydro-flattened Raster DEM.

Geographic Extent: Parts of 14 counties in California, covering approximately 2097 total square miles. These counties are: Alameda, Contra Costa, Marin, Napa, Sacramento, San Francisco, San Joaquin, San Mateo, Santa Clara, Solano, Sonoma, Stanislaus, Sutter, Yolo.

Dataset Description: The SanFrancisco_Baylands_Lidar project called for the planning, acquisition, processing, and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.29 meters. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base LiDAR Specification, 2024 Rev. A. LiDAR data were delivered as processed Classified LAS 1.4 files formatted to individual 600 m x 600 m tiles, as tiled intensity imagery, and as tiled bare earth DEMs; all tiled to the same 600 m x 600 m schema. Continuous breaklines were produced in Esri file geodatabase format.

Ground Conditions: LiDAR was collected in summer and fall 2025, while no snow was on the ground and rivers were at or below normal levels. In order to post process the LiDAR data to meet task order specifications and meet ASPRS vertical accuracy guidelines, NV5 Geospatial utilized a total of 51 ground control points that were used to calibrate the LiDAR to known ground locations established throughout the project area. An additional 115 independent accuracy checkpoints, 84 in Bare Earth and Urban landcovers (84 NVA points), 31 in Tall Weeds categories (31 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. The following four tiles in State Plane Zone 3 are empty due to being entirely over water: 10339968, 09130148, 07930588, and 01731068.

These data were provided to the NOAA Office for Coastal Management (OCM) from the San Francisco Estuary Institute (SFEI) for the purpose of making the data publicly available for custom and bulk downloads from the NOAA Digital Coast Data Access Viewer.

To acquire detailed surface elevation data for use in conservation planning, design, research, floodplain mapping, dam safety assessments and elevation modeling, etc. Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create intensity images, breaklines and raster DEMs. The purpose of these LiDAR data was to produce high accuracy 3D hydro-flattened digital elevation models (DEMs) with a 1 foot cell size. These raw LiDAR point cloud data were used to create classified LiDAR LAS files, intensity images, 3D breaklines, and hydro-flattened DEMs as necessary.

Raster File Type = GeoTIFF; Bit Depth/Pixel Type = 32-bit float; Raster Cell Size = 1 foot; Interpolation or Resampling Technique = Triangulated Irregular Network (TIN), Linear Interpolation, Proprietary; Required Vertical Accuracy = 0.196

Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners.

To the extent possible under law, the U.S. Government has waived all copyright and related or neighboring rights to this dataset.

Data is available online for bulk and custom downloads.

None

Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.

This data set was produced to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 13 (cm) RMSEh Horizontal Accuracy Class which equates to Positional Horizontal Accuracy = +/- 22 cm at a 95% confidence level.

The DEM tested 6.62 cm NVA at a 95% confidence level (or 3.38 cm RMSE) using 84 independent survey points located in open terrain. The survey check points were distributed throughout the project area. The 84 independent check points were surveyed using GPS techniques. See survey report for additional survey methodologies.

The DEM tested 28.89 cm VVA (Vegetated Vertical Accuracy) at the 95th percentile.

Datasets contain complete coverage of tiles. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. There are no void areas or missing data. The raw point cloud is of good quality and data pass Non-Vegetated Vertical Accuracy specifications.

Data cover the entire area specified for this project.

The NOAA Office for Coastal Management (OCM) received the GeoTIFF files from the San Francisco Estuary Institute (SFEI).