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GAMA OnLine Tools

The State Water Board GAMA Program and the U.S. Geological Survey have created tools to help users understand groundwater quality in California. The following online tools allow users to access data through web maps and data querying tools.

Recommended browser is Google Chrome. If you have any problems when using these tools, please contact Dori Bellan.


GAMA groundwater-information system

GAMA Groundwater Information System

 - The GAMA Program’s online groundwater information system integrates and displays groundwater quality data from several different sources on an interactive Google-based map interface. This system provides access to approximately 87 million analytical results from over 290,000 wells in California. Analytical tools and reporting features help users assess groundwater quality and identify potential groundwater issues in California.



Trend Analysis Tool

Trend Analysis Tool

 - The U.S. Geological Survey trends analysis tool allows the user to observe trends in 38 inorganic constituents from the GAMA Priority Basin Project, alongside the same inorganic constituents from the Division of Drinking Water public supply drinking water data. Several tools to analyze trends are included, as well as the ability to differentiate between statistically-significant increasing or decreasing trends, and trends dependent of well depth.



Domestic Well Water Quality Tool

Domestic Well Water Quality Tool

 - The State Water Board GAMA Program developed methodology to estimate the water quality in domestic wells as part of the second element of the Needs Analysis of the state of drinking water in California. This element identifies the location and number of domestic wells potentially accessing groundwater affected by constituents at concentrations above regulatory thresholds. Domestic depth groundwater quality estimates for six constituents are shown on the map: nitrate, arsenic, hexavalent chromium, uranium, 1,2,3 trichloropropane (123 TCP), and perchlorate. For each constituent, groundwater quality estimates can be displayed for all Public Land Survey System (PLSS) sections statewide, or for only the PLSS sections that include at least one domestic well (domestic well counts and locations were obtained from the Department of Water Resources Online System of Well Completion Reports).



2021 Aquifer Risk Map

2021 Aquifer Risk Map for Domestic and State Small Water Systems

 - The Aquifer Risk Map is an interactive web tool designed to identify areas of the state where domestic wells (serving less than five connections) and state small water systems (serving between 5 and 15 connections) may be at a relatively higher risk of accessing groundwater that does not meet primary drinking water standards. The aquifer risk map was developed to fulfill requirements included in Senate Bill 200 (Monning, statues of 2019) and is a component of California’s Safe and Affordable Funding for Equity and Resilience (SAFER) program. The primary purpose of this map interface is to inform Water Boards staff in support of the SAFER annual Fund Expenditure Plan. In accordance with SB 200, the Aquifer Risk Map will be updated on an annual basis. See the white paper presenting the methodology behind this map. See the SAFER program for additional information.



GAMA groundwater-information system

U.S. Geological Survey Groundwater Quality Mapping Tool

 - The U.S. Geological Survey has created the Groundwater Quality Results Mapping Tool. This interactive web map plots water-quality data from domestic and public-supply wells sampled by the USGS for the California GAMA Priority Basin Project, and allows users to download datasets.



GAMA groundwater-information system

GAMA Groundwater Publications Webmap

 - The GAMA Program’s publications are all available through the new GAMA Publications webmap. This interactive web map displays all published reports from GAMA projects, while also providing study unit information. Reference layers are also available for spatial comparisons.



Groundwater Vulnerability Using Relative Groundwater Age

Groundwater Vulnerability Using Relative Groundwater Age

 - This tool is intended to provide a knowledge of relative groundwater age across California, using the tritium-helium dating technique employed by the GAMA Program work with the LLNL, previously published. It allows the user to analyze relative groundwater age of the tritium-containing groundwater (young portion) to observe vulnerability to groundwater contamination via recharge.



Is My Property Near a 123-TCP Impacted Water Well?

Is My Property Near a 123-TCP Impacted Water Well?

 - This interactive tool is intended for private domestic well owners to evaluate if their well is near a 1,2,3-Trichloropropane-impacted well. Enter your address or point of interest into the search bar to locate impacted wells nearby. Additional information about 123-TCP is provided.



Is My Property Near a Nitrate Impacted Water Well?

Is My Property Near a Nitrate Impacted Water Well?

 - This interactive tool is intended for private domestic well owners to evaluate if their well is near a nitrate-impacted well. Enter your address or point of interest into the search bar (top left) to locate impacted wells nearby. Additional information about nitrate is provided.



Salt and Nutrient Management Plans Webmap

Salt and Nutrient Management Plans Webmap

 - As part of the Recycled Water Policy adopted by the State Water Board, agencies, municipalities, and local stakeholders are to develop salt and nutrient management plans (SNMPs) for groundwater basins in California. This webmap tracks the status of SNMP development.




Source Water Protection Webmap

Source Water Protection Webmap - (Coming Soon!)

 - A webmap will provide spatial data for analysis and download, including groundwater source well locations, surface water intakes, vulnerability assessments, nearby potentially contaminating activities, and other data relevant to source water protection. The site will also provide an application to create source water assessments required for drinking water sources.



Digitized Well Completion Reports

Digitized Well Completion Reports - (Coming Soon!)

 - Lead by the U.S. Geological Survey, the GAMA Program is digitizing well completion reports as we analyze the groundwater quality of shallow aquifers across California. Digitized data will include latitude/longitude, type of well, year completed, total depth, top of opening depth and number of openings, aquifer type, depth to static water level, including a link to the well completion report.