California Groundwater Basin Subsidence Measurements 2015-2022

January 2015 to April 2022 vertical ground displacement measurements for over 200 high-use groundwater basins in California. Data is derived from Sentinel-1A satellite InSAR and processed by TRE ALTAMIRA for the California Department of Water Resources. It includes point data for 100m x 100m areas and interpolated GIS rasters for total and annual displacement.

Use Cases

• Analyze monthly time-step vertical displacement rasters to identify subsidence hotspots correlated with groundwater extraction.
• Model long-term subsidence trends using total vertical displacement data relative to the June 13, 2015 baseline.
• Validate InSAR-derived point time series data against independent Continuous GPS station measurements for accuracy assessment.
• Map annual vertical displacement rates across different groundwater basins to support Groundwater Sustainability Plan (GSP) development.

Strengths

• Covers over 200 populated and high-use groundwater basins across California.
• Provides data from January 2015 to April 2022, with some areas having coverage from late 2014.
• Includes both point data for 100m x 100m areas and interpolated GIS raster formats.
• Data was independently validated against Continuous GPS station data by Towill Inc.

Limitations

• Data is provided in PDF, ZIP, and HTML formats, which are not immediately machine-readable for large-scale analysis without extraction.
• The spatial resolution is at the 100m x 100m area level, which may not capture very localized displacement features.
• Coverage for the entire study area began in June 2015, creating a slightly shorter time series for some basins compared to others.

Provenance

Source

TRE ALTAMIRA Inc., under contract with the California Department of Water Resources.

Collection Method

Vertical displacement estimates derived from ESA Sentinel-1A satellite InSAR data, processed into point data and interpolated GIS rasters.

Time Range

January 2015 to April 2022, with some areas from late 2014 and full coverage from June 13, 2015.

Freshness

Data is updated quarterly, with reports updated annually; last platform update was March 2026.

Geography

Over 200 groundwater basins across the State of California, United States.