The Water Data Library (WDL) provides public access to three distinct environmental data stores within DWR.  The WDL provides access to these data through a map interface as well as search forms specific to each dataset. 

For the best experience, we recommend using an up-to date version Chrome, Firefox or Edge.

The Department of Water Resources makes no warranties, representations or guarantees, either expressed or implied, as to the accuracy, completeness, correctness, or timeliness of the information in the datasets that are accessible through the Water Data Library, nor accepts or assumes any liability arising from use of the Water Data Library or underlying data. Neither the Department nor any of the sources of the information utilized by the Water Data Library shall be responsible for any errors or omissions, or for the use or results obtained from the use of this information. Classifications and boundaries shown in this viewer are graphical representations only, and do not establish legal rights or define legal boundaries.  

The WDL publishes 3 separate datasets:  Discrete Water Quality, Discrete Groundwater Measurements, and Continuous Data.  These are described below.

This database hold information on discrete water quality samples collected from the early 1900s to present for a variety of programs within DWR.  While there are some programs within DWR that may have additional water quality data not contained in this database, the majority of discrete water quality samples taken by DWR and analyzed by DWR’s Bryte Environmental Laboratory are contained within this database.
 

This is the primary groundwater elevation measurement database maintained by DWR.  This database holds information on monitoring stations (generally groundwater wells) and groundwater elevation measurements collected under CASGEM, SGMA, and other programs, from the late 1890s to present.  Data within this database were collected by DWR as well as local, other state, and federal agencies such as the USGS, and reported to DWR.  In most cases, these are manual measurements of groundwater elevation, though the system also contains some automated measurements of groundwater elevation.
 

These stations have automated systems that periodically (typically hourly or every 15 minutes), but other intervals are used by some stations) measure environmental variables.  Data in this dataset was collected from around 1930 to present, with the majority of the data collected since 1980.  These stations fall into 3 subcategories:  surface water stations (and tidal) that measure stage and/or flow of surface water features such as streams; water quality stations that measure water quality parameters such as pH, salinity, and dissolved oxygen in surface water features; and groundwater stations that measure groundwater elevation and related measurements typically in groundwater wells.