This digital dataset contains three types of information about the land use properties used in the updated Central Valley Hydrologic Model (CVHM2): land use shapefile showing primary land use type for a model cell through time, soil data using the curve number for each region and zone, and farm process parameter values including crop coefficients and rooting depths.

The shapefile in this data release is the updated Central Valley Hydrologic Model (CVHM2) model grid cells with yearly land use from 1921 to 2019. Historical land use data shows the Central Valley land use prior to agricultural development. The rise of agriculture in the Central Valley is visible over time in this data set. Existing land use maps covering the Central Valley were used as sources and were assigned to model grids cells for their observed land use year. This source data was used to estimate land use over time for years where no land use map was available. This was accomplished by comparing land use cells between two years where source data is available. Cells where there is no land use change remain the same and are assigned that land use over the years with missing data. Where land use change occurs, cells are assigned the land use in the newer map based on the area of the new land use and the number of years with missing data.

This digital dataset contains the soil data for the updated Central Valley Hydrologic Model (CVHM2). The soil data is based on California Department of Water Resource’s C2VSim’s fine grid model soil curve number data set (C2VSimFG Version 1.0 - Datasets; CNRA, 2011). These values were originally obtained from the U.S. Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS) Soil Survey Geographic Database (SSURGO) soil map of the State of California (USDA, 2004), and then an area-weighted average value for each hydrologic soil group within each subregion was calculated to the C2VSim element. Curve number values obtained from SSURGO were converted for use in C2VSimFG. To translate the curve number from the C2VSim grid to the CVHM2 grid, the curve number from the C2VSim that covered the largest area of a CVHM2 cell was used as zone number. There were 8 unique curve numbers in C2VSimFG. Then each of these numbers were given a different zone number for each of the four regions (Sacramento, Delta-Eastside, San Joaquin, and Tulare), resulting in 26 unique zones for CVHM2. The use of regional zones for curve numbers along with that introduced by the large scale of cell sizes (one square mile) introduces some unavoidable errors into the calculations, but this is expected for errors inherent in estimating runoff rates over such a large area without using a dedicated and complex model (Loague and Freeze, 1985).

This digital dataset includes three sets of observational data (groundwater level, streamflow, subsidence) used to calibrate the updated Central Valley Hydrologic Model (CVHM2). CVHM2 is a tool that can be used to quantify the sustainability of groundwater resources in the Central Valley.

This digital dataset consists of monthly climate data from the Basin Characterization Model v8 (BCMv8) for the updated Central Valley Hydrologic Model (CVHM2) for water years 1922 to 2019. The BCMv8 data are available in a separate data release titled "The Basin Characterization Model - A regional water balance software package (BCMv8) data release and model archive for hydrologic California, water years 1896-2020". The data were modified by: (1) extracting the data from the data source for the relevant model domain and times, and (2) rescaling the 270-meter BCMv8 grid to the small watersheds that contribute boundary flow to the CVHM2 model for the hydrologic variables recharge and runoff. The three data pieces included are a CSV file of monthly recharge and runoff values in units of acre-ft/month for each of the 56 small watersheds, a shapefile of the the foothill boundaries for the small watersheds and a shapefile of the model boundary cells and runoff cells that are active for the small watersheds.

This data release consists of climate data from the Basin Characterization Model v8 (BCMv8) for the updated Central Valley Hydrologic Model (CVHM2) for water years 1922-2019. The BCMv8 data are available in separate data release titled "The Basin Characterization Model - A regional water balance software package (BCMv8) data release and model archive for hydrologic California, water years 1896-2020". The data were modified by: (1) clipping the data within the modeled area and modeled time frame, and (2) assigning values from the 270-meter BCMv8 grid to the1-mile CVHM2 model grid for the hydrologic variables precipitation and potential evapotranspiration.

This digital dataset contains groundwater level observations for 364 wells, in addition to well construction information, from 1916 to 2014 in the Central Valley, California. Groundwater level observations are used to create groundwater level contours and to calibrate the groundwater levels for the updated Central Valley Hydrologic Model (CVHM2). Groundwater level observations were collected from five sources (USGS, 2018; SLDMWA, 2018; CADWR, 2004; CRNA, 2018).

This digital dataset consists of monthly climate data from the Basin Characterization Model v8 (BCMv8) for the updated Central Valley Hydrologic Model (CVHM2) for water years 1922 to 2019. The BCMv8 data are available in a separate data release titled "The Basin Characterization Model - A regional water balance software package (BCMv8) data release and model archive for hydrologic California, water years 1896-2020" that accompanies the USGS Techniques and Methods report titled: "The Basin Characterization Model - A Regional Water Balance Software Package". The BCMv8 data are extracted from the state-wide data for the CVHM2 modeled area for water years 1922 to 2019. Climate data for CVHM2 are presented in two child items: precipitation and potential evapotranspiration extracted for the modeled area within the CVHM2 model boundary; recharge and runoff are extracted for the small watersheds surrounding the CVHM2 model boundary. Each child items contain metadata, a shapefile, a file containing the data.