In order to provide an accurate data set of service area boundaries for California drinking water systems, the Division of Drinking Water of the California Water Resources Control Board (SWRCB DDW) has undertaken a project to vet and verify the data collected by the Tracking California's Water Boundary Tool (WBT).Note: This feature layer is updated on a regular basis. However, in some locations where it is shared, it shows the “Data Updated” date as the last time the item has changed, not the data. To accurately determine when the data was last updated, open the data table and sort by Last Edited Date field.SWRCB DDW downloaded a copy of the current water system service areas loaded in the WBT as of June 27, 2019. Additional attribute fields indicating verification status, verification staff and system type were appended to the data set. SWRCB DDW staff are reviewing and validating the displayed boundaries of each service area as well as contacting the service providers regarding necessary corrections. The verification status of any particular service area may be found in the Verification Status field.For any questions regarding this dataset, please contact the Data Support Unit at DDW-DSU@waterboards.ca.gov.

This is the archived 2022 version of the Aquifer Risk Map. The most recent version is available here.This aquifer risk map is developed to fulfill requirements of SB-200 and is intended to help prioritize areas where domestic wells and state small water systems may be accessing raw source groundwater that does not meet primary drinking water standards (maximum contaminant level or MCL). In accordance with SB-200, the risk map is to be made available to the public and is to be updated annually starting January 1, 2021. The Fund Expenditure Plan states the risk map will be used by Water Boards staff to help prioritize areas for available SAFER funding. This is the final 2022 map based upon feedback received from the 2021 map. A summary of methodology updates to the 2022 map can be found here.This map displays raw source groundwater quality risk per square mile section. The water quality data is based on depth-filtered, declustered water quality results from public and domestic supply wells. The process used to create this map is described in the 2022 Aquifer Risk Map Methodology document. Data processing scripts are available on GitHub. Download/export links are provided in this app under the Data Download widget.This version was last updated December 1, 2021.Water quality risk: This layer contains summarized water quality risk per square mile section and well point. The section water quality risk is determined by analyzing the long-tern (20-year) section average and the maximum recent (within 5 years) result for all sampled contaminants. These values are compared to the MCL and sections with values above the MCL are “high risk”, sections with values within 80%-100% of the MCL are “medium risk” and sections with values below 80% of the MCL are “low risk”. The specific contaminants above or close to the MCL are listed as well. The water quality data is based on depth-filtered, de-clustered water quality results from public and domestic supply wells.Individual contaminants: This layer shows de-clustered water quality data for arsenic, nitrate, 1,2,3-trichloropropane, uranium, and hexavalent chromium per square mile section.Domestic Well Density: This layer shows the count of domestic well records per square mile. The domestic well density per square mile is based on well completion report data from the Department of Water Resources Online System for Well Completion Reports, with records drilled prior to 1970 removed and records of “destruction” removed.State Small Water Systems: This layer displays point locations for state small water systems based on location data from the Division of Drinking Water.Public Water System Boundaries: This layer displays the approximate service boundaries for public water systems based on location data from the Division of Drinking Water.Reference layers: This layer contains several reference boundaries, including boundaries of CV-SALTS basins with their priority status, Groundwater Sustainability Agency boundaries, census block group boundaries, county boundaries, and groundwater unit boundaries.

This is the 2022 version of the Aquifer Risk Map. The 2021 version of the Aquifer Risk Map is available here.This aquifer risk map is developed to fulfill requirements of SB-200 and is intended to help prioritize areas where domestic wells and state small water systems may be accessing raw source groundwater that does not meet primary drinking water standards (maximum contaminant level or MCL). In accordance with SB-200, the risk map is to be made available to the public and is to be updated annually starting January 1, 2021. The Fund Expenditure Plan states the risk map will be used by Water Boards staff to help prioritize areas for available SAFER funding. This is the final 2022 map based upon feedback received from the 2021 map. A summary of methodology updates to the 2022 map can be found here.This map displays raw source groundwater quality risk per square mile section. The water quality data is based on depth-filtered, declustered water quality results from public and domestic supply wells. The process used to create this map is described in the 2022 Aquifer Risk Map Methodology document. Data processing scripts are available on GitHub. Download/export links are provided in this app under the Data Download widget.This draft version was last updated December 1, 2021. Water quality risk: This layer contains summarized water quality risk per square mile section and well point. The section water quality risk is determined by analyzing the long-tern (20-year) section average and the maximum recent (within 5 years) result for all sampled contaminants. These values are compared to the MCL and sections with values above the MCL are “high risk”, sections with values within 80%-100% of the MCL are “medium risk” and sections with values below 80% of the MCL are “low risk”. The specific contaminants above or close to the MCL are listed as well. The water quality data is based on depth-filtered, de-clustered water quality results from public and domestic supply wells.Individual contaminants: This layer shows de-clustered water quality data for arsenic, nitrate, 1,2,3-trichloropropane, uranium, and hexavalent chromium per square mile section. Domestic Well Density: This layer shows the count of domestic well records per square mile. The domestic well density per square mile is based on well completion report data from the Department of Water Resources Online System for Well Completion Reports, with records drilled prior to 1970 removed and records of “destruction” removed.State Small Water Systems: This layer displays point locations for state small water systems based on location data from the Division of Drinking Water.Public Water System Boundaries: This layer displays the approximate service boundaries for public water systems based on location data from the Division of Drinking Water.Reference layers: This layer contains several reference boundaries, including boundaries of CV-SALTS basins with their priority status, Groundwater Sustainability Agency boundaries, census block group boundaries, county boundaries, and groundwater unit boundaries. ArcGIS Web Application

Use Constraints:This mapping tool is for reference and guidance purposes only and is not a binding legal document to be used for legal determinations. The data provided may contain errors, inconsistencies, or may not in all cases appropriately represent the current boundaries of PWSs in California. The data in this map are subject to change at any time and should not be used as the sole source for decision making. By using this data, the user acknowledges all limitations of the data and agrees to accept all errors stemming from its use.Description:This mapping tool provides a representation of the general PWS boundaries for water service, wholesaler and jurisdictional areas. The boundaries were created originally by collection via crowd sourcing by CDPH through the Boundary Layer Tool, this tool was retired as of June 30, 2020. State Water Resources Control Board – Division of Drinking Water is currently in the process of verifying the accuracy of these boundaries and working on a tool for maintaining the current boundaries and collecting boundaries for PWS that were not in the original dataset. Currently, the boundaries are in most cases have not been verified. Map Layers· Drinking Water System Areas – representation of the general water system boundaries maintained by the State Water Board. This layer contains polygons with associated data on the water system and boundary the shape represents.· LPA office locations – represents the locations of the Local Primacy Agency overseeing the water system in that county. Address and contact information are attributes of this dataset.· LPA office locations – represents the locations of the Local Primacy Agency overseeing the water system in that county. Address and contact information are attributes of this dataset· California Senate Districts – represents the boundaries of the senate districts in California included as a reference layer in order to perform analysis with the Drinking Water System Boundaries layers.· California Senate Districts – represents the boundaries of the assembly districts in California included as a reference layer in order to perform analysis with the Drinking Water System Boundaries layers.· California County – represents the boundaries of the counties in California included as a reference layer in order to perform analysis with the Drinking Water System Boundaries layers.Informational Pop-up Box for Boundary layer· Water System No. – unique identifier for each water system· Water System Name – name of water system· Regulating Agency – agency overseeing the water system· System Type – classification of water system.· Population the approximate population served by the water system· Boundary Type – the type of water system boundary being displayed· Address Line 1 – the street or mailing address on file for the water system· Address Line 2 – additional line for street or mailing address on file for the water system, if applicable· City – city where water system located or receives mail· County – county where water system is located· Verification Status – the verification status of the water system boundary· Verified by – if the boundary is verified, the person responsible for the verification Date Created and Sources:This web app was most recently updated on July, 21, 2021. Each layer has a data created date and data source is indicated in the overview/metadata page and is valid up to the date provided.

This is a modified version of the DDW California Drinking Water System Area Boundaries (SABL) data. This was created by the Needs Analysis Unit (NAU) to aide in GIS analysis for the Needs Assessment and Affordability Assessment. Currently it contains 5,322 water system service area boundaries.Changes include:Addition of "Artificial Boundaries" for systems missing service area boundaries. When comparing the total number of available water systems on the original SABL layer to the Needs Assessment inventory there are 157 missing systems. Those systems are given a proxy boundary in order to include them within the analysis. These boundaries are made by creating 0.5-mile buffers around point locations tied to the water system. The point locations can be well heads, physical locations, treatment facilities, storage tanks, or any other component of the water system. The buffer is added to provide a two-dimensional aspect to the artificial boundaries to give them an area of coverage. The total diameter of these buffers is 1-mile.Removal of duplicate water system boundaries. Some water systems can have multiple boundary types from the original SABL layer. For instance, a water system can have a service area boundary and a jurisdictional boundary. For the purposes of the Risk Assessment all water system included only have one boundary where service area is given preference when available.Total boundary types: 5,322Water Service Area: 5,132Jurisdictional: 7Wholesaler: 26Artificial: 157In order to provide an accurate data set of service area boundaries for California drinking water systems, the Division of Drinking Water of the California Water Resources Control Board (SWRCB DDW) has undertaken a project to vet and verify the data collected by the Tracking California's Water Boundary Tool (WBT).SWRCB NAU downloaded a copy of the current water DDW California Drinking Water System Area Boundaries map on January 27th, 2025. This dataset is updated on a quarterly basis.For any questions regarding this dataset, please contact the Data Support Unit at DDW-SAFER-NAU@Waterboards.ca.gov.

The California State Water Resources Control Board (State Water Board) and the nine Regional Water Quality Control Boards (Regional Water Boards), collectively known as the California Water Boards (Water Boards), are dedicated to a single vision: abundant clean water for human uses and environmental protection to sustain California’s future. Under the federal Clean Water Act (CWA) and the state’s pioneering Porter-Cologne Water Quality Control Act, the State and Regional Water Boards have regulatory responsibility for protecting the water quality of nearly 1.6 million acres of lakes, 1.3 million acres of bays and estuaries, 211,000 miles of rivers and streams, and about 1,100 miles of California coastline.The State Water Board is located in Sacramento. There are nine Regional Water Boards, the boundaries of which are generally based on watersheds, also known as hydrologic areas. The nine Regional Water Boards are referred to by specific names, which are: (1) North Coast, (2) San Francisco Bay, (3) Central Coast, (4) Los Angeles, (5) Central Valley, (6) Lahontan, (7) Colorado River Basin, (8) Santa Ana, and (9) San Diego. Due to their size, and/or geographic spread, the Central Valley Board has three offices and the Lahontan Board has two offices. In addition, the Drinking Water Program has fourteen District offices spread throughout the state.This map service shows the jurisdictional boundaries of the nine Regional Water Boards and the locations of their administrative offices. The official legal definitions of Regional Water Quality Control Board jurisdictions may be found in the Section 13200 of the California Water Code.For more information, please visit the California Water Boards website at https://www.waterboards.ca.gov.

The SaveWater.CA.Gov is an online tool to help save water in California communities. The data to support the application comes from two sources: Public Water Systems boundary information from the California Environmental Health Tracking Program (CEHTP) Drinking Water Systems Geographic Reporting Tool (CDPH) and Public Water Systems contact information from the CA State Water Resources Control Board Drinking Water Program.

This layer is a combination of data sources. California water systems are regulated and tracked differently based on system classification and and size, so a single layer dataset for all drinking water systems in California was created in order to make consolidation and partnership outreach simpler.

The California Drinking Water System Area Boundaries (SABL) are publicly available. SABL is the database of record for public drinking water systems. The locations are verified as the best available data and include over 4,000 water systems. Collecting and verifying SABL boundaries is an ongoing effort. There are public water systems (mostly non-community) that do not yet have a boundary in the SABL dataset. These systems have been geocoded from their Physical Locations in the State Drinking Water Information System (SDWIS) portal, with light data cleaning. Eventually these systems will be captured in SABL.State Small Water Systems are non-public water systems that are regulated by County health officials in partnership with the State Water Board. These systems have been geocoded from their Physical Locations using the most recent County-provided data, with light data cleaning. Eventually, these systems may be found in SABL.

Attribute Definitions

System ID - The Public Water System ID (PWSID), an identifier assigned by the state. System Name - Name of the water system. System Type - State classification of a system. Options here include Community, Non-Transient Non-Community, Transient Non-Community, and State Small Water Systems. County - The principal county served by the identified system. Regulator - The agency responsible for regulating the system(s) involved. Risk Status - The Risk status data point differs for public water systems and state smalls.

For public water systems, the risk status is based on the 2021 Needs Assessment:

HR2W or Human Right to Water At-Risk Potentially At-Risk Not-At Risk No data

For state small water systems, the risk status is based on the 2022 Aquifer Risk and reflects the local Aquifer drinking water quality:

High contaminant risk Medium contaminant risk Low contaminant risk No data

Connections - Number of physical connections to a water systems distribution infrastructure. Population - Number of persons served by a water system. Owner Type - Most California water systems are privately owned and operated. Other Owner Type options include Federal Govt, State Govt, Local Govt, Mixed ownership, and Native/Tribal ownership. Admin Address, City, State, Zip, Email, Phone - Administrative Contact information for water systems are included. Only one Administrative Contact per system is included for the sake of simplicity in the map. For outreach purposes, additional Administrative Contacts can be found using the public Drinking Water Watch portal.

Interactive GIS Mapping Tool – Urgent Drinking Water Needs (UDWN) Web Map in California

Use Constraints:

This mapping tool is for reference and guidance purposes only and is not a binding legal document to be used for legal determinations. The data provided may contain errors, inconsistencies, or may not in all cases appropriately represent the current status of Urgent Drinking Water Needs project locations. The data in this map are subject to change at any time and should not be used as the sole source for decision making. By using this data, the user acknowledges all limitations of the data and agrees to accept all errors stemming from its use. The Urgent Drinking Water Needs map does not provide the locations of individual households that were provided funding through grant agreements with non-profit organizations.

Description:

This map displays Urgent Drinking Water Needs due to drought, contamination, or other eligible emergencies. This includes projects approved for funding from July 1, 2014 to November 18, 2022, including both active and completed projects. The data comes from the State Water Resources Control Board (SWRCB) Cleanup and Abatement Account’s (CAA) project database and was exported on November 18, 2022. The map contains four layers: UDWN_Projects, UDWN_Summary_by_county, CA_Assembly_Districts_WEB, and CA_Senate_Districts_WEB.

The attributes for each project in the UDWN_Projects layer include the recipient of grant funding (grantee), community served, type of project, grant amount, funding program, date the project was approved, date the project was completed, Disadvantaged Community status, Small Disadvantaged Community status, the public water system number, status of the project (Active or Completed), and the state fiscal year in which the project was approved.

How to Use the Interactive Mapping Tool:When the map loads, it displays the state of California, UDWN Project locations, and California county boundaries. The “About” tab is located on the left-hand side of the map and displays instructions for using the map. The next tab display pre-set filters, the legend, and a layer list. Clicking on the “Legend” tab in the menu will show the legend of the map. Projects that appear as blue dots are still active, while projects that appear as red dots have already been completed.Note: Layers that show CA Assembly and Senate Districts were created by the Sierra Nevada Conservancy (SNC). These layers must be toggled on in the layers list to be seen. To view information about a specific project, click on a project location. A pop-up box will appear with the following information: (a) county name, (b) community served, (c) type of project, (d) approved funding amount, (e) approval date, and (f) status. To view information about the total funding and number of projects in a county, click within a county boundary and a pop up will appear.Use the pre-set filters to filter projects by status, fiscal year, funding program, county, assembly district, and/or senate district using the drop-down menu. The filters can be toggled on or off using the switches on the right side of the menu. To create a custom filter, click the filter icon at the bottom of the preset filter menu and enter the desired parameters. For one parameter, click “add expression” to create a custom filter. For more than one, click “add set” to create a custom filter.To export and download filtered data, open the Attribute Table located at the bottom of the map, click the “Options” drop down menu, select “Export all to CSV” from the drop-down menu, and download the desired information.

Map Layers:UDWN_Projects – This layer shows all active or completed UDWN projects from July 1, 2014 to November 18, 2022. Active projects are represented with blue dots while completed projects are represented with red dots. The attributes in this layer include what county the project is in, the community served, the type of project, approved funding amount, approval date, and status.UDWN_Summary_by_county – This layer shows the boundary lines for all the counties in California. The attributes in this layer include the total number of projects and total funding approved in that county since July 1, 2014. CA_Assembly_Districts_WEB – This layer shows the boundary lines for all the assembly districts in California. It is owned and maintained by the Sierra Nevada Conservancy (SNC) and boundaries may not be accurate. CA_Senate_Districts_WEB – This layer shows the boundary lines for all the senate districts in California. It is owned and maintained by the Sierra Nevada Conservancy (SNC) and boundaries may not be accurate.

Informational Pop-up Box:County – California county where the project is locatedCommunity Served – California community that is benefiting from UDWN funding Type of Project – Project type, which can include bottled water, consolidation, hauled water, pilot study, POU, pump, tank, treatment, and well Approved Funding Amount – Amount of money in U.S. dollars approved for the projectApproval Date – Date that the project was approved for fundingStatus – Current status of the project (active or closed)Date Created:

Data created on November 18, 2022 and valid up to this date.

Sources:

Urgent Drinking Water Needs data was exported from the CAA Database.

The Sierra Nevada Conservancy (SNC) created the California Senate and Assembly layers.

Points of Contact:

Christina Raynard is the creator and owner of this layer. Christina.raynard@waterboards.ca.gov (State Water Resources Control Board, Division of Financial Assistance)

Terms of Use

No special restrictions or limitations on using the item’s content have been provided.

Drinking Water - SAFER Dashboard Failing and At-Risk Drinking Water SystemsDrought is a regional hazard; a community's susceptibility to it is influenced primarily by the status of their water system. During periods of drought, communities served by at-risk water systems could lose access to safe drinking water. Drought impacts water quality because decreasing well water levels lead to increased concentrations of contaminants such as arsenic. A lack of clean, sufficient well water can cause financial burden, sanitation concerns, and other issues for communities that rely on active wells for bathing, washing dishes, and other daily needs. This map layer draws data from State assessments of the hundreds of water systems across the county. The Division of Drinking Water (DDW) identifies Failing and At-Risk community water systems and K-12 non-transient, non-community schools. This information is displayed online in the Safe and Affordable Funding for Equity and Resilience (SAFER) Dashboard. The data utilized for this assessment is derived from multiple sources: self-reported from water systems, data generated by DDW staff, other California state agencies, and U.S. Census. The data sources, calculation methods, Failing and At-Risk criteria, etc. are fully documented in the annual Drinking Water Needs Assessment report which is published annually on the State Water Board’s website.SAFER Dashboard: https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/saferdashboard.htmlAttribute Data: https://data.ca.gov/dataset/safer-failing-and-at-risk-drinking-water-systemsWater System Boundaries: https://gispublic.waterboards.ca.gov/portal/home/item.htmlData from the SAFER Dashboard joined to water system boundaries using the Water System ID. If no matching Water System ID, the nearest boundary to the point location noted in the SAFER dataset was used.This dataset is updated nightly from the Attribute Data source above.

This data release contains site information and potential explanatory factor data for 1,899 groundwater sites. These sites were used to assess groundwater quality in aquifers used for domestic and public drinking water supply in the southeastern San Joaquin Valley. The southeastern San Joaquin Valley (SESJV) study unit consists of five study areas whose boundaries are defined by the eponymous California Department of Water Resources groundwater subbasins of the San Joaquin Valley groundwater basin: Madera-Chowchilla, Kings, Kaweah, Tule, and Tulare Lake. The sites consist of 198 wells representing the domestic-supply aquifer and 1,701 wells representing the public-supply aquifer. The domestic-supply aquifer wells were sampled in 2013-2015 by the USGS for either the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) or the USGS National Water Quality Assessment project (NAWQA). The public-supply aquifer wells were either sampled by the USGS for the GAMA-PBP in 2005-2018 or have water-quality data in the California State Water Resources Control Board Division of Drinking Water (SWRCB-DDW) public database. The data types in this data release include site identification and location, well construction and lithology data, land use characteristics, groundwater age and oxidation-reduction classifications and aridity indices. Not all sites have data for all fields. Water-quality data for the sites are available from U.S. Geological Survey (2023), and California State Water Resources Control Board Division of Drinking Water (2023). The study design and the assessment results are presented in Burow and others (2024).

The Aquifer Risk Map Web Tool contains all archived maps, including this 2023 Aquifer Risk Map.The Aquifer Risk Map is developed to fulfill requirements of SB-200 (Monning, 2019) and is intended to help prioritize areas where domestic wells and state small water systems may be accessing groundwater that does not meet primary drinking water standards (maximum contaminant level or MCL). In accordance with SB-200, the map is made available to the public and updated annually starting January 1, 2021. This web map is part of the 2023 Aquifer Risk Map. The Fund Expenditure Plan states the risk map will be used by Water Boards staff to help prioritize areas for available SAFER funding.

This web map includes the following layers:Water Quality Risk: water quality risk estimates per square mile section for all contaminants with an MCL. Water quality risk is listed as “high” (average or recent concentration in section is above MCL for one or more contaminants), “medium” (average or recent concentration in section is between 80% - 100% of MCL for one or more contaminants), “low” (average or recent concentration in section is less than 80% of MCL for all measured contaminants) or “unknown” (no water quality data available in section).Individual Contaminant Risk: water quality risk estimates for nitrate, arsenic, 1,2,3-trichloropropane, hexavalent chromium, and uranium per square mile section.State Small Water Systems (DDW): state small water systems (5-14 connections) location from the Division of Drinking Water joined with water quality risk section estimates from the 2023 Aquifer Risk Map.Domestic Well Records (OSWCR): the approximate count and location of domestic well completion reports submitted to the Department of Water Resources. This is used as a proxy to identify domestic well locations.Public Water System Boundaries (DDW): the approximate boundaries of public drinking water systems, from the Division of Drinking Water. For reference only.Census Areas: Census block groups and census tract boundaries containing demographic information from the 2021 American Community Survey (B19013 Median Household Income and B03002 race/ethnicity) joined with summarized water quality risk estimates from the 2023 Aquifer Risk Map (count of high risk domestic wells and state small water systems per census area).Reference Boundaries: Various geographic boundaries including counties, basins, GSA’s, CV-SALTS basin prioritization status, Disadvantaged Community (DAC) status, and legislative boundaries. For reference only.CalEnviroScreen 4.0: CalEnviroScreen scores from OEHHA. For reference only.Groundwater Level Percentiles (DWR): Groundwater depth in various monitoring wells compared to the historic average at that well. For reference only.

The water quality risk is based on depth-filtered, de-clustered water quality results from public and domestic supply wells. The methodology used to determine water quality risk is outlined here. For more information about the SAFER program, please email SAFER@waterboards.ca.gov. For technical questions or feedback on the map please email GAMA@waterboards.ca.gov.

The aquifer risk map is being developed to fulfill requirements of SB-200 and is intended to help prioritize areas where domestic wells and state small water systems may be accessing groundwater that does not meet primary drinking water standards (maximum contaminant level or MCL). In accordance with SB-200, the risk map is to be made available to the public and is to be updated annually starting January 1, 2021. The Fund Expenditure Plan states the risk map will be used by Water Boards staff to help prioritize areas for available SAFER funding.Methodology for the draft aquifer risk map available for download.This layer shows the locations of state small water systems. The state small water system locations were collected by the Rural Community Assistance Corporation. The locations are approximate and may not exactly represent well locations or service boundaries.

A water system’s customer service area is the geographic location that they serve in California. This means all residential and commercial customer connections for which the water system has a permit to provide services and can bill payment. This information is not considered sensitive or confidential.

The ascii grids associated with this data release are predicted distributions of continuous pH at the drinking water depth zones in the groundwater of Central Valley, California. The two prediction grids produced in this work represent predicted pH at the domestic supply and public supply drinking water depths, respectively and are bound by the alluvial boundary that defines the Central Valley. A depth of 46 m was used to stratify wells into the shallow and deep aquifer and were derived from depth percentiles associated with domestic and public supply in previous work by Burow et al. (2013). In this work, the median well depth categorized as domestic supply was 30 meters below land surface and the median well depth categorized as public supply is 100 meters below land surface. Prediction grids were created using prediction modeling methods, specifically Boosted Regression Trees (BRT) with a gaussian error distribution within a statistical learning framework within R's computing framework (http://www.r-project.org/). The statistical learning framework seeks to maximize the predictive performance of machine learning methods through model tuning by cross validation. The response variable was measured pH from 1337 wells, and was compiled from two sources: US Geological Survey (USGS) National Water Information System (NWIS) Database (all data are publicly available from the USGS: http://waterdata.usgs.gov/ca/nwis/nwis) and the California State Water Resources Control Board Division of Drinking Water (SWRCB-DDW) database (water quality data are publicly available from the SWRCB: http://www.waterboards.ca.gov/gama/geotracker_gama.shtml). Only wells with measured pH and well depth data were selected, and for wells with multiple records, only the most recent sample in the period 1993-2014 was used. A total of 1003 wells (training dataset) were used to train the BRT model and 334 wells (hold-out dataset) were used to validate the prediction model. The training r-squared was 0.70 and the RMSE in standard pH units was were 0.26. The holdout r-squared was 0.43 and RMSE in standard pH units was 0.37. Predictor variables consisting of more than 60 variables from 7 sources (see metadata) were assembled to develop a model that incorporates regional-scale soil properties, soil chemistry, land use, aquifer textures, and aquifer hydrology. Previously developed Central Valley model outputs of textures (Central Valley Textural Model, CVTM; Faunt et al. 2010) and MODFLOW-simulated vertical water fluxes and predicted depth to water table (Central Valley Hydrologic Model, CVHM; Faunt, 2009) were used to represent aquifer textures and groundwater hydraulics, respectively. In this work, wells were attributed to predictor variable values in ArcGIS using a 500-m buffer. Results of the predictor variable influence as defined by Friedman (2001) for variables used in the final BRT model used for mapping can be downloaded from this landing page (see file named PredictorVariableInfluence_CentralValley_pH_BRT.csv).

The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide, comprehensive assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is being implemented by the California State Water Resources Control Board. The USGS is the technical lead for the Priority Basin Project (PBP), one of the components of the GAMA Program. The initial focus of the GAMA Priority Basin Project in 2004 to 2012 was on assessment of water-quality in groundwater resources used for public drinking water supply (Belitz and others, 2003; 2015). Groundwater basins and sub-basins (472 in total) were prioritized based upon a number of factors (Belitz and others 2003). Two hundred and twenty-seven of these basins and additional areas outside of basins were subsequently grouped into 35 study units comprising 87 Study Areas. The basin and sub-basin boundaries, local geology, local knowledge, and watershed data were used to define the Study Areas. The Study Areas each were divided into equal-area grid cells collectively referred as a "study area grid". The number and size of cells generated for each Study Area was based upon the size of the area being sampled, and the number of public-supply wells available to sample. Three Study Areas contained an insufficient number of public-supply wells for division into a study area grid and were instead directly sampled. The number of cells in a study area grid ranged from 7 to 122 (median 20), and the size of the cells ranged from 4 to 471 km2 (median 25 km2). Additional information about the design of individual study area grids can be found in the reports listed below. The 87 Study Areas are collected and assembled here into one GIS dataset.

This dataset represents polygon boundaries of all public water agencies in California including public water systems, agricultural water districts, urban water districts, Federal and State water contractors, wholesalers, retailers, and other public or private utilities that deliver water to the end user.

In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within California’s State Waters. The program supports a large number of coastal-zone- and ocean-management issues, including the California Marine Life Protection Act (MLPA) (California Department of Fish and Wildlife, 2008), which requires information about the distribution of ecosystems as part of the design and proposal process for the establishment of Marine Protected Areas. A focus of CSMP is to map California’s State Waters with consistent methods at a consistent scale. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data (the undersea equivalent of satellite remote-sensing data in terrestrial mapping), acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. It is emphasized that the more interpretive habitat and geology data rely on the integration of multiple, new high-resolution datasets and that mapping at small scales would not be possible without such data. This approach and CSMP planning is based in part on recommendations of the Marine Mapping Planning Workshop (Kvitek and others, 2006), attended by coastal and marine managers and scientists from around the state. That workshop established geographic priorities for a coastal mapping project and identified the need for coverage of “lands” from the shore strand line (defined as Mean Higher High Water; MHHW) out to the 3-nautical-mile (5.6-km) limit of California’s State Waters. Unfortunately, surveying the zone from MHHW out to 10-m water depth is not consistently possible using ship-based surveying methods, owing to sea state (for example, waves, wind, or currents), kelp coverage, and shallow rock outcrops. Accordingly, some of the data presented in this series commonly do not cover the zone from the shore out to 10-m depth. This data is part of a series of online U.S. Geological Survey (USGS) publications, each of which includes several map sheets, some explanatory text, and a descriptive pamphlet. Each map sheet is published as a PDF file. Geographic information system (GIS) files that contain both ESRI ArcGIS raster grids (for example, bathymetry, seafloor character) and geotiffs (for example, shaded relief) are also included for each publication. For those who do not own the full suite of ESRI GIS and mapping software, the data can be read using ESRI ArcReader, a free viewer that is available at http://www.esri.com/software/arcgis/arcreader/index.html (last accessed September 20, 2013). The California Seafloor Mapping Program is a collaborative venture between numerous different federal and state agencies, academia, and the private sector. CSMP partners include the California Coastal Conservancy, the California Ocean Protection Council, the California Department of Fish and Wildlife, the California Geological Survey, California State University at Monterey Bay’s Seafloor Mapping Lab, Moss Landing Marine Laboratories Center for Habitat Studies, Fugro Pelagos, Pacific Gas and Electric Company, National Oceanic and Atmospheric Administration (NOAA, including National Ocean Service–Office of Coast Surveys, National Marine Sanctuaries, and National Marine Fisheries Service), U.S. Army Corps of Engineers, the Bureau of Ocean Energy Management, the National Park Service, and the U.S. Geological Survey. These web services for the Offshore of Ventura map area includes data layers that are associated to GIS and map sheets available from the USGS CSMP web page at https://walrus.wr.usgs.gov/mapping/csmp/index.html. Each published CSMP map area includes a data catalog of geographic information system (GIS) files; map sheets that contain explanatory text; and an associated descriptive pamphlet. This web service represents the available data layers for this map area. Data was combined from different sonar surveys to generate a comprehensive high-resolution bathymetry and acoustic-backscatter coverage of the map area. These data reveal a range of physiographic including exposed bedrock outcrops, large fields of sand waves, as well as many human impacts on the seafloor. To validate geological and biological interpretations of the sonar data, the U.S. Geological Survey towed a camera sled over specific offshore locations, collecting both video and photographic imagery; these “ground-truth” surveying data are available from the CSMP Video and Photograph Portal at https://doi.org/10.5066/F7J1015K. The “seafloor character” data layer shows classifications of the seafloor on the basis of depth, slope, rugosity (ruggedness), and backscatter intensity and which is further informed by the ground-truth-survey imagery. The “potential habitats” polygons are delineated on the basis of substrate type, geomorphology, seafloor process, or other attributes that may provide a habitat for a specific species or assemblage of organisms. Representative seismic-reflection profile data from the map area is also include and provides information on the subsurface stratigraphy and structure of the map area. The distribution and thickness of young sediment (deposited over the past about 21,000 years, during the most recent sea-level rise) is interpreted on the basis of the seismic-reflection data. The geologic polygons merge onshore geologic mapping (compiled from existing maps by the California Geological Survey) and new offshore geologic mapping that is based on integration of high-resolution bathymetry and backscatter imagery, seafloor-sediment and rock samples, digital camera and video imagery, and high-resolution seismic-reflection profiles. The information provided by the map sheets, pamphlet, and data catalog has a broad range of applications. High-resolution bathymetry, acoustic backscatter, ground-truth-surveying imagery, and habitat mapping all contribute to habitat characterization and ecosystem-based management by providing essential data for delineation of marine protected areas and ecosystem restoration. Many of the maps provide high-resolution baselines that will be critical for monitoring environmental change associated with climate change, coastal development, or other forcings. High-resolution bathymetry is a critical component for modeling coastal flooding caused by storms and tsunamis, as well as inundation associated with longer term sea-level rise. Seismic-reflection and bathymetric data help characterize earthquake and tsunami sources, critical for natural-hazard assessments of coastal zones. Information on sediment distribution and thickness is essential to the understanding of local and regional sediment transport, as well as the development of regional sediment-management plans. In addition, siting of any new offshore infrastructure (for example, pipelines, cables, or renewable-energy facilities) will depend on high-resolution mapping. Finally, this mapping will both stimulate and enable new scientific research and also raise public awareness of, and education about, coastal environments and issues. Web services were created using an ArcGIS service definition file. The ArcGIS REST service and OGC WMS service include all Monterey Canyon and Vicinity map area data layers. Data layers are symbolized as shown on the associated map sheets.

This dataset represents a water shortage vulnerability analysis performed by DWR using Small Water System boundaries pulled from the SWRCB (State Water Resource Control Board) water system boundary layer (SABL). The water systems were then restricted to only active water systems with under 3000 connections that had SDWIS (Safe Drinking Water Information System) data. This data is from the 2024 analysis.

The spatial data of these feature classes is used as units of analysis for the spatial analysis performed by DWR. These datasets are intended to be authoritative datasets of the scoring tools required from DWR according to Senate Bill 552. Please refer to the source metadata for more information on completeness.

The associated data are considered DWR enterprise GIS data, which meet all appropriate requirements of the DWR Spatial Data Standards, specifically the DWR Spatial Data Standard version 3.4, dated September 14, 2022. DWR makes no warranties or guarantees — either expressed or implied— as to the completeness, accuracy, or correctness of the data. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data. Comments, problems, improvements, updates, or suggestions should be forwarded to GIS@water.ca.gov.

In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within California’s State Waters. The program supports a large number of coastal-zone- and ocean-management issues, including the California Marine Life Protection Act (MLPA) (California Department of Fish and Wildlife, 2008), which requires information about the distribution of ecosystems as part of the design and proposal process for the establishment of Marine Protected Areas. A focus of CSMP is to map California’s State Waters with consistent methods at a consistent scale. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data (the undersea equivalent of satellite remote-sensing data in terrestrial mapping), acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. It is emphasized that the more interpretive habitat and geology data rely on the integration of multiple, new high-resolution datasets and that mapping at small scales would not be possible without such data. This approach and CSMP planning is based in part on recommendations of the Marine Mapping Planning Workshop (Kvitek and others, 2006), attended by coastal and marine managers and scientists from around the state. That workshop established geographic priorities for a coastal mapping project and identified the need for coverage of “lands” from the shore strand line (defined as Mean Higher High Water; MHHW) out to the 3-nautical-mile (5.6-km) limit of California’s State Waters. Unfortunately, surveying the zone from MHHW out to 10-m water depth is not consistently possible using ship-based surveying methods, owing to sea state (for example, waves, wind, or currents), kelp coverage, and shallow rock outcrops. Accordingly, some of the data presented in this series commonly do not cover the zone from the shore out to 10-m depth. This data is part of a series of online U.S. Geological Survey (USGS) publications, each of which includes several map sheets, some explanatory text, and a descriptive pamphlet. Each map sheet is published as a PDF file. Geographic information system (GIS) files that contain both ESRI ArcGIS raster grids (for example, bathymetry, seafloor character) and geotiffs (for example, shaded relief) are also included for each publication. For those who do not own the full suite of ESRI GIS and mapping software, the data can be read using ESRI ArcReader, a free viewer that is available at http://www.esri.com/software/arcgis/arcreader/index.html (last accessed September 20, 2013). The California Seafloor Mapping Program is a collaborative venture between numerous different federal and state agencies, academia, and the private sector. CSMP partners include the California Coastal Conservancy, the California Ocean Protection Council, the California Department of Fish and Wildlife, the California Geological Survey, California State University at Monterey Bay’s Seafloor Mapping Lab, Moss Landing Marine Laboratories Center for Habitat Studies, Fugro Pelagos, Pacific Gas and Electric Company, National Oceanic and Atmospheric Administration (NOAA, including National Ocean Service–Office of Coast Surveys, National Marine Sanctuaries, and National Marine Fisheries Service), U.S. Army Corps of Engineers, the Bureau of Ocean Energy Management, the National Park Service, and the U.S. Geological Survey. These web services for the Hueneme Canyon map area includes data layers that are associated to GIS and map sheets available from the USGS CSMP web page at https://walrus.wr.usgs.gov/mapping/csmp/index.html. Each published CSMP map area includes a data catalog of geographic information system (GIS) files; map sheets that contain explanatory text; and an associated descriptive pamphlet. This web service represents the available data layers for this map area. Data was combined from different sonar surveys to generate a comprehensive high-resolution bathymetry and acoustic-backscatter coverage of the map area. These data reveal a range of physiographic including exposed bedrock outcrops, large fields of sand waves, as well as many human impacts on the seafloor. To validate geological and biological interpretations of the sonar data, the U.S. Geological Survey towed a camera sled over specific offshore locations, collecting both video and photographic imagery; these “ground-truth” surveying data are available from the CSMP Video and Photograph Portal at https://doi.org/10.5066/F7J1015K. The “seafloor character” data layer shows classifications of the seafloor on the basis of depth, slope, rugosity (ruggedness), and backscatter intensity and which is further informed by the ground-truth-survey imagery. The “potential habitats” polygons are delineated on the basis of substrate type, geomorphology, seafloor process, or other attributes that may provide a habitat for a specific species or assemblage of organisms. Representative seismic-reflection profile data from the map area is also include and provides information on the subsurface stratigraphy and structure of the map area. The distribution and thickness of young sediment (deposited over the past about 21,000 years, during the most recent sea-level rise) is interpreted on the basis of the seismic-reflection data. The geologic polygons merge onshore geologic mapping (compiled from existing maps by the California Geological Survey) and new offshore geologic mapping that is based on integration of high-resolution bathymetry and backscatter imagery seafloor-sediment and rock samplesdigital camera and video imagery, and high-resolution seismic-reflection profiles. The information provided by the map sheets, pamphlet, and data catalog has a broad range of applications. High-resolution bathymetry, acoustic backscatter, ground-truth-surveying imagery, and habitat mapping all contribute to habitat characterization and ecosystem-based management by providing essential data for delineation of marine protected areas and ecosystem restoration. Many of the maps provide high-resolution baselines that will be critical for monitoring environmental change associated with climate change, coastal development, or other forcings. High-resolution bathymetry is a critical component for modeling coastal flooding caused by storms and tsunamis, as well as inundation associated with longer term sea-level rise. Seismic-reflection and bathymetric data help characterize earthquake and tsunami sources, critical for natural-hazard assessments of coastal zones. Information on sediment distribution and thickness is essential to the understanding of local and regional sediment transport, as well as the development of regional sediment-management plans. In addition, siting of any new offshore infrastructure (for example, pipelines, cables, or renewable-energy facilities) will depend on high-resolution mapping. Finally, this mapping will both stimulate and enable new scientific research and also raise public awareness of, and education about, coastal environments and issues. Web services were created using an ArcGIS service definition file. The ArcGIS REST service and OGC WMS service include all Hueneme Canyon map area data layers. Data layers are symbolized as shown on the associated map sheets.