DWR continuous groundwater level measurements contains continuous time-series data from automated recorders at sites operated by the Department of Water Resources. Readings are taken at 15-minute to one-hour intervals. Some of the readings are relayed to the California Data Exchange Center. However, most of the monitoring sites are visited once every month or two, when readings are off-loaded from data recorders, then finalized and published. Wells monitored for this dataset are located within Butte, Colusa, Glenn, Mendocino, Modoc, Sacramento, San Joaquin, Shasta, Siskiyou, Solano, Sutter, Tehama, Yolo, and Yuba Counties. Water-level measurements are the principal source of information about changes in groundwater storage and movement in a basin, and how these are affected by various forms of recharge (e.g., precipitation, seepage from streams, irrigation return) and discharge (e.g., seepage to streams, groundwater pumping). Water-level monitoring involves "continuous" or periodic measurements. Continuous monitoring makes use of automatic water-level sensing and recording instruments that are programmed to make scheduled measurements in wells. This provides a high-resolution record of water-level fluctuations. Resulting hydrographs can accurately identify the effects of various stresses on the aquifer system and provide measurements of maximum and minimum water levels in aquifers. Continuous monitoring may be the best technique to use for monitoring fluctuations in groundwater levels during droughts and other critical periods when hydraulic stresses may change at relatively rapid rates, or when real-time data are needed for making water management decisions [see usgs reference](https://ca.water.usgs.gov/sustainable-groundwater-management/groundwater-levels-california.html).

The DWR Periodic Groundwater Levels dataset contains seasonal and long-term groundwater level measurements collected by the Department of Water Resources and cooperating agencies in groundwater basins statewide. It also includes data collected through the Sustainable Groundwater Management Act (SGMA) Portal’s Monitoring Network Module (MNM), and the CASGEM (California Statewide Groundwater Elevation Monitoring) Program. Most measurements are taken manually twice per year to capture the peak high and low values in groundwater elevations. However, the dataset also includes measurements recorded more frequently, monthly, weekly, or daily. This resource also included daily measurements from DWR's automated monitoring network of groundwater sites. For DWRs holdings of groundwater level measurements recorded at more frequent intervals (e.g., hourly), please refer to DWR's “Continuous Groundwater Level Measurements” dataset. For additional information regarding DWR groundwater levels data collection please visit DWR's Groundwater Management website (https://www.water.ca.gov/Programs/Groundwater-Management). The source data can also be accessed directly from two websites. The Water Data Library (http://wdl.water.ca.gov) provides anonymous access to this and other data sets. The CASGEM online system (https://www.casgem.water.ca.gov/OSS) provides authenticated access to only the the periodic groundwater measurements. This dataset is maintained primarily in the DWR Enterprise Water Management database and contains information specific to the location of groundwater level monitoring wells and groundwater level measurements collected at these wells. The Stations resource identifies well location coordinates and other supplementary items about the well type. Measurements resources includes information about the time/date a measurement was collected, the entity collecting the measurement, a measurement indicating the depth to groundwater, and quality information about the measurement. The Well Perforations resources contains well construction information identifying the well's screened intervals (not available for all wells).

The DWR Periodic Groundwater Levels dataset contains seasonal and long-term groundwater level measurements collected by the Department of Water Resources and cooperating agencies in groundwater basins statewide. It also includes data collected through the Sustainable Groundwater Management Act (SGMA) Portal’s Monitoring Network Module (MNM), and the CASGEM (California Statewide Groundwater Elevation Monitoring) Program. Most measurements are taken manually twice per year to capture the peak high and low values in groundwater elevations. However, the dataset also includes measurements recorded more frequently, monthly, weekly, or daily. This resource also included daily measurements from DWR's automated monitoring network of groundwater sites. For DWRs holdings of groundwater level measurements recorded at more frequent intervals (e.g., hourly), please refer to DWR's “Continuous Groundwater Level Measurements” dataset. For additional information regarding DWR groundwater levels data collection please visit DWR's Groundwater Management website (https://www.water.ca.gov/Programs/Groundwater-Management). The source data can also be accessed directly from two websites. The Water Data Library (http://wdl.water.ca.gov) provides anonymous access to this and other data sets. The CASGEM online system (https://www.casgem.water.ca.gov/OSS) provides authenticated access to only the the periodic groundwater measurements. This dataset is maintained primarily in the DWR Enterprise Water Management database and contains information specific to the location of groundwater level monitoring wells and groundwater level measurements collected at these wells. The Stations resource identifies well location coordinates and other supplementary items about the well type. Measurements resources includes information about the time/date a measurement was collected, the entity collecting the measurement, a measurement indicating the depth to groundwater, and quality information about the measurement. The Well Perforations resources contains well construction information identifying the well's screened intervals (not available for all wells).

Stations and a table of download links for time-series data, from DWR's continuous environmental monitoring database. For more information, see DWR's Water Data Library, continuous data section: https://wdl.water.ca.gov/ContinuousData.aspx, where this data is also available.

Stations and a table of download links for time-series data, from DWR's continuous environmental monitoring database. For more information, see DWR's Water Data Library, continuous data section: https://wdl.water.ca.gov/ContinuousData.aspx, where this data is also available.

The Community Groundwater Level Monitoring Program is a voluntary, locally driven effort designed to strengthen drought resilience and fill critical groundwater data gaps across the region. The program is built around three complementary components: domestic wells, schools, and small water systems. Community members with domestic wells can participate by collecting simple water-level measurements using equipment and training provided free of charge by the Department of Water Resources (DWR). In exchange, participants agree to submit their data to DWR’s public groundwater databases, helping create a more complete and transparent picture of groundwater conditions in areas where monitoring is limited. The school and small water system components support implementation of SB 552, which requires improved drought planning and early warning capabilities for vulnerable water supplies. By partnering with schools and small water systems to install dedicated monitoring equipment and collect consistent data, the program provides timely information that can be used for drought preparedness, resource planning, and community outreach. Together, these three components form a flexible, community-centered network that expands groundwater understanding and supports long-term water reliability for all.

The Community Groundwater Level Monitoring Program is a voluntary, locally driven effort designed to strengthen drought resilience and fill critical groundwater data gaps across the region. The program is built around three complementary components: domestic wells, schools, and small water systems. Community members with domestic wells can participate by collecting simple water-level measurements using equipment and training provided free of charge by the Department of Water Resources (DWR). In exchange, participants agree to submit their data to DWR’s public groundwater databases, helping create a more complete and transparent picture of groundwater conditions in areas where monitoring is limited. The school and small water system components support implementation of SB 552, which requires improved drought planning and early warning capabilities for vulnerable water supplies. By partnering with schools and small water systems to install dedicated monitoring equipment and collect consistent data, the program provides timely information that can be used for drought preparedness, resource planning, and community outreach. Together, these three components form a flexible, community-centered network that expands groundwater understanding and supports long-term water reliability for all.

The Department of Water Resources (DWR) Enterprise Monitoring Well Network dataset contains information regarding wells monitored by DWR. The wells included in this dataset have been completed, a well completion report (WCR) has been submitted through the Online System for Well Completion Reports (OSWCR), and have been registered either through the California Statewide Groundwater Elevation Monitoring (CASGEM) Online System or the Sustainable Groundwater Management Act (SGMA) Portal’s Monitoring Network Module (MNM). This dataset will be updated on a monthly basis.

The Department of Water Resources (DWR) Enterprise Monitoring Well Network dataset contains information regarding wells monitored by DWR. The wells included in this dataset have been completed, a well completion report (WCR) has been submitted through the Online System for Well Completion Reports (OSWCR), and have been registered either through the California Statewide Groundwater Elevation Monitoring (CASGEM) Online System or the Sustainable Groundwater Management Act (SGMA) Portal’s Monitoring Network Module (MNM). This dataset will be updated on a monthly basis.

The Department of Water Resources Telemetered Wells dataset contains information regarding wells within the DWR monitoring network that have telemetry equipment installed. The wells included in this dataset have been completed, a well completion report (WCR) has been submitted through the Online System for Well Completion Reports (OSWCR), and have been registered either through the California Statewide Groundwater Elevation Monitoring (CASGEM) Online System or the Sustainable Groundwater Management Act (SGMA) Portal’s Monitoring Network Module (MNM).