Map of the known geothermal resource areas from the California Department of Conservation, CalGEM 2002.

This online map represents geothermal wells regulated by the Geologic Energy Management Division.

CalGEM is the Geologic Energy Management Division of the California Department of Conservation, formerly the Division of Oil, Gas, and Geothermal Resources (as of January 1, 2020).

This data layer contains geothermal resource areas and their technical potential used in long-term electric system modeling for Integrated Resource Planning and SB 100. Geothermal resource areas are delineated by Known Geothermal Resource Areas (KGRAs) (Geothermal Map of California, 2002), other geothermal fields (CalGEM Field Admin Boundaries, 2020), and Bureau of Land Management (BLM) Geothermal Leasing Areas (California BLM State Office GIS Department, 2010). The fields that are considered in our assessment have enough information known about the geothermal reservoir that an electric generation potential was estimated by USGS (Williams et al. 2008) or estimated by a BLM Environmental Impact Statement (El Centro Field Office, 2007). For the USGS identified geothermal systems, any point that lies within 2 km of a field is summed to represent the total mean electrical generation potential from the entire field.

Geothermal field boundaries are constructed for identified geothermal systems that lie outside of an established geothermal field. A circular footprint is assumed with a radius determined by the area needed to support the mean resource potential estimate, assuming a 10 MW/km² power density.

Several geothermal fields have power plants that are currently generating electricity from the geothermal source. The total production for each geothermal field is estimated by the CA Energy Commission’s Quarterly Fuel and Energy Report that tracks all power plants greater than 1 MW. The nameplate capacity of all generators in operation as of 2021 were used to inform how much of the geothermal fields are currently in use. This source yields inconsistent results for the power plants in the Geysers. Instead, an estimate from the net energy generation from those power plants is used. Using these estimates, the net undeveloped geothermal resource potential can be calculated.

Finally, we apply the protected area layer for geothermal to screen out those geothermal fields that lie entirely within a protected area. The protected area layer is compiled from public and private lands that have special designations prohibiting or not aligning with energy development.

This layer is featured in the CEC 2023 Land-Use Screens for Electric System Planning data viewer.

For more information about this layer and its use in electric system planning, please refer to the Land Use Screens Staff Report in the CEC Energy Planning Library.

Change Log:

Version 1.1 (January 18, 2024)

• ProtectedArea_Exclusion field was updated to correct for the changes to the Protected Area Layer. A Development Focus Area on Bureau of Land Management (BLM) land that overlays the Coso Hot Springs allows its resource potential to be considered in the statewide estimate.

Data Dictionary:

Total_MWe_Mean: The estimated resource potential from each geothermal field. All geothermal fields, except for Truckhaven, was given an estimate by Williams et al. 2008. If more than one point resource intersects (within 2km of) the field, the sum of the individual geothermal systems was used to estimate the magnitude of the resource coming from the entire geothermal field. Estimates are given in MW.

Total_QFER_NameplateCapacity: The total nameplate capacities of all generators in operation as of 2021 that intersects (within 2 km of) a geothermal field. The resource potential already in use for the Geysers is determined by Lovekin et al. 2004. Estimates are given in MW.

ProtectedArea_Exclusion: Binary value representing whether a field is excluded by the land-use screen or not. Fields that are excluded have a value of 1; those that aren’t have a value of 0.

NetUndevelopedRP: The net undeveloped resource potential for each geothermal field. This field is determined by subtracting the total resource potential in use (Total_QFER_NameplateCapacity) from the total estimated resource potential (Total_MWe_Mean). Estimates are given in MW.

Acres_GeothermalField: This is the geodesic acreage of each geothermal field. Values are reported in International Acres using a NAD 1983 California (Teale) Albers (Meters) projection.

References:

1. Geothermal Map of California, S-11. California Department of Conservation, 2002. https://www.conservation.ca.gov/calgem/geothermal/maps/Pages/index.aspx
2. CalGEM Field Admin Boundaries, 2020. https://gis.conservation.ca.gov/server/rest/services/CalGEM/Admin_Bounds/MapServer
   
3. California BLM State Office GIS Department, California BLM Verified and Potential Geothermal Leases in California, 2010. https://databasin.org/datasets/5ec77a1438ab4402bf09ef9bfd7f04d9/
   
4. Williams, Colin F., Reed, Marshall J., Mariner, Robert H., DeAngelo, Jacob, Galanis, S. Peter, Jr. 2008. "Assessment of moderate- and high-temperature geothermal resources of the United States: U.S. Geological Survey Fact Sheet 2008-3082." 4 p. https://certmapper.cr.usgs.gov/server/rest/services/geothermal/westus_favoribility_systems/MapServer/0
5. El Centro Field Office, Bureau of Land Management (2007). Final Environmental Impact Statement for the Truckhaven Geothermal Leasing Area (Publication Index Number: BLM/CA/ES-2007-017+3200). United States Department of the Interior Bureau of Land Management.
6. Lovekin, James W., Subir K. Sanyal, Christopher W. Klein. 2004. “New Geothermal Site Identification and Qualification.” Richmond, California:

Map showing geothermal fields, known geothermal resource areas, high-temperature wells, geothermal springs, and power plants. Inset map of low-temperature wells and select commercial low-temperature projects in CA. Scanned Map S-11.

This resource is metadata for a Bibliography of California Geothermal Publications. It was compiled by the Arizona Geological Survey, made available for distribution through the AASG Geothermal Data System and published as an Excel workbook containing header features including title, description, author, citation, originator, distributor, and resource URL links to scanned maps for download. The Excel workbook contains 6 worksheets, including information about the template, notes related to revisions of the template, Resource provider information, the data, a field list and vocabularies for use in populating the data worksheet (data valid terms).

Geologic Data Map No. 4: Geothermal Resources of California. 2010 Geologic Map of California. This resource is available for purchase in hard copy format by the California Geological Survey. For more information see links provided.

There are 487 onshore oil and gas fields in California encompassing 3,392 square miles of aggregated area. The California State Water Resources Control Board (State Water Board) initiated a Regional Monitoring Program (RMP) in July 2015, intended to determine where and to what degree groundwater quality may be at potential risk to contamination related to oil and gas development activities including well stimulation, well integrity issues, produced water ponds, and underground injection. The first step in monitoring groundwater in and near oil and gas fields is to prioritize the 487 fields using consistent statewide analysis of available data that indicate potential risk of groundwater to oil and gas development. There were limited existing data on potential groundwater risk factors available for oil and gas fields across the state. During 2014-2016, the U.S. Geological Survey (USGS) extracted and compiled data from various sources, including the California Division of Oil, Gas, and Geothermal Resources (DOGGR) and the Department of Water Resources (DWR). Geospatial data from the DOGGR were used in the prioritization analysis. Dataset include geospatial data for 222,637 petroleum wells, administrative boundaries for 514 oil, gas, and geothermal fields, and boundaries for DOGGR's 6 juristictional districts. The data were downloaded from DOGGR's Geographic Information System (GIS) Mapping website at http://www.conservation.ca.gov/dog/maps. The DOGGR GIS Mapping website is periodally updated, and the datasets downloaded by the U.S. Geological Survey in 2014 may no longer be available on the DOGGR website.

This compilation provides metadata for documents and maps related to geothermal data in California. The compilation is published as an Excel workbook containing header features including title, description, author, citation, originator, distributor, and resource URL links to scanned maps for download. The Excel workbook contains 6 worksheets, including information about the template, notes related to revisions of the template, resource provider information, the data, a field list, and vocabularies (data valid terms) used to populate the data worksheet. This resource was provided by the Arizona Geological Survey and made available for distribution through the National Geothermal Data System.

Energy capacity data and map are from the California Energy Commission. Map depicts geothermal energy capacity by county. Unshaded counties had no commercial geothermal energy capacity. Data is from 2022 and is current as of May 14, 2024. Projection: NAD 1983 (2011) California (Teale) Albers (Meters). For more information, contact John Hingtgen at 916 510-9747 or Jessica Lin at 415 990-8392.

Lands Valuable For Geothermal Resources Northern California

No Publication Abstract is Available

The datasets that are included in the composite layer making up the protected area layer are given below: DatasetExample DesignationsCitation or hyperlinkPAD-US (CBI Edition)National Parks, GAP Status 1 and 2, State Parks, Open Spaces, Natural Areas“PAD-US (CBI Edition) Version 2.1b, California”. Conservation Biology Institute. 2016. https://databasin.org/datasets/64538491f43e42ba83e26b849f2cad28.Conservation EasementsCalifornia Conservation Easement Database (CCED), 2022a. 2022. www.CALands.org. Accessed December 2022. Inventoried Roadless Areas“Inventoried Roadless Areas.” US Forest Service. Dec 12, 2022. https://www.fs.usda.gov/detail/roadless/2001roadlessrule/maps/?cid=stelprdb5382437BLM National Landscape Conservation SystemWilderness Areas, Wilderness Study Areas, National Monuments, National Conservation Lands, Conservation Lands of the California Desert, Scenic Rivershttps://gbp-blm-egis.hub.arcgis.com/datasets/BLM-EGIS::blm-ca-wilderness-areashttps://gbp-blm-egis.hub.arcgis.com/datasets/BLM-EGIS::blm-ca-wilderness-study-areashttps://gbp-blm-egis.hub.arcgis.com/datasets/BLM-EGIS::blm-ca-national-monuments-nca-forest-reserves-other-poly/Greater Sage Grouse Habitat Conservation Areas (BLM)For solar technology: BLM_Managm IN (‘PHMA’, ‘GHMA’, ‘OHMA’)For wind technology: BLMP_Managm = ‘PHMA’“Nevada and Northeastern California Greater Sage-Grouse Approved Resource Management Plan Amendment.” US Department of the Interior Bureau of Land Management Nevada State Office. 2015. https://eplanning.blm.gov/public_projects/lup/103343/143707/176908/NVCA_Approved_RMP_Amendment.pdf Other BLM Protected AreasAreas of Critical Environmental Concern (ACECs), Recreation Areas (SRMA, ERMA, OHV Designated Areas), including Vinagre Wash Special Recreation Management Area, National Scenic Areas, including Alabama Hills National Scenic Areahttps://gbp-blm-egis.hub.arcgis.com/datasets/BLM-EGIS::blm-ca-off-highway-vehicle-designations

This resource is a compilation of thermal spring temperature observations compiled by the Arizona Geological Survey, published as a Web feature service for the AASG National Geothermal Data System. The data is available in the following formats: web feature service, web map service, ESRI service and an Excel workbook for download. The workbook contains 6 worksheets, including information about the template, notes related to revisions of the template, resource provider information, the data, a field list (data mapping view) and a worksheet with vocabularies for use in populating the data worksheet (data valid terms). This data was provided by the California Division of Oil, Gas and Geothermal Resources and made available for distribution through the AASG National Geothermal Data Systems project.

This geologic map database is a reproduction of U.S. Geological Survey Miscellaneous Investigations Map I–2362: “Geologic Map and Structure Sections of the Clear Lake Volcanics, Northern California” (Hearn, Donnelly-Nolan, and Goff, 1995). The database consists of a geologic map, three structural cross sections and a table of petrographic data for each map unit by mineral type, abundance, and size. The Clear Lake Volcanics are in the California Coast Ranges about 150 km north of San Francisco. This Quaternary volcanic field has erupted intermittently since 2.1 million years ago. This volcanic field is considered a high-threat volcanic system (Ewert and others, 2005). The adjacent Geysers geothermal field, the largest power-producing geothermal field in the world, is powered by the magmatic heat source for the volcanic field. The geology of parts of the area underlain by the Cache Formation is based on mapping by Rymer (1981); the geology of parts of the areas underlain by the Sonoma Volcanics, Franciscan assemblage, and Great Valley sequence is based on mapping by McLaughlin (1978). Volcanic compositional map units are basalt, basaltic andesite, andesite, dacite, rhyodacite, and rhyolite, based on SiO2 content. Most ages are potassium-argon (K/Ar) ages determined for whole-rock samples and mineral separates by Donnelly-Nolan and others (1981), unless otherwise noted. A few ages are carbon-14 ages or were estimated from geologic relationships. Magnetic polarities are from Mankinen and others (1978; 1981) or were determined in the field by B.C. Hearn, Jr., using a portable fluxgate magnetometer. Thickness for most units is estimated from topographic relief except where drill-hole data were available. This database does not reproduce all elements of the original publication. Omissions include the chart and figures showing erupted volumes of different lava types through time, and the chart and diagram for the correlation of map units. Users of this database are highly encouraged to cross reference this database with the original publication.

description: This dataset is a compilation of Well header information compiled by the California Division of Oil, Gas and Geothermal Resources, published as a Web feature service, a web map service, an ESRI service, and as a set of Excel spreadsheets for the National Geothermal Data System. The spreadsheet contains 8 worksheets, including information about the template, notes related to revisions of the template, Resource provider information, the data, a field list (data mapping view) and a worksheet with vocabularies for use in populating the spreadsheet (data valid terms). Data from 23,198 wells are included. Fields found in the template are: HeaderURI, WellName , APINo, OtherID, OtherName, BoreholeName, ParentWellURI, Operator, MineralOwner, Driller, LeaseName, SpudDate, EndedDrillingDate, DrillingMethod, WellType, Status, CommodityOfInterest, StatusDate, Function, Production , ProducingInterval , ReleaseDate, County, State, Field, OtherLocationName, PLSS_Meridians, TWP, RGE, Section_, SectionPart, Parcel, UTM_E, UTM_N, UTMDatumZone, LatDegree, LongDegree, SRS, LocationUncertaintyStatement, LocationUncertaintyCode, LocationUncertaintyRadius, DrillerTotalDepth, DepthReferencePoint, LengthUnits, WellBoreShape, TrueVerticalDepth, ElevationKB, ElevationDF, ElevationGL, FormationTD, BitDiameterCollar, BitDiameterTD, DiameterUnits, RelatedResource, Notes, CasingLogger, CasingBottomDepthDriller, CasingTopDepth, CasingPipeDiameter, CasingWeight, CasingWeightUnits, CasingThickness and InformationSource.; abstract: This dataset is a compilation of Well header information compiled by the California Division of Oil, Gas and Geothermal Resources, published as a Web feature service, a web map service, an ESRI service, and as a set of Excel spreadsheets for the National Geothermal Data System. The spreadsheet contains 8 worksheets, including information about the template, notes related to revisions of the template, Resource provider information, the data, a field list (data mapping view) and a worksheet with vocabularies for use in populating the spreadsheet (data valid terms). Data from 23,198 wells are included. Fields found in the template are: HeaderURI, WellName , APINo, OtherID, OtherName, BoreholeName, ParentWellURI, Operator, MineralOwner, Driller, LeaseName, SpudDate, EndedDrillingDate, DrillingMethod, WellType, Status, CommodityOfInterest, StatusDate, Function, Production , ProducingInterval , ReleaseDate, County, State, Field, OtherLocationName, PLSS_Meridians, TWP, RGE, Section_, SectionPart, Parcel, UTM_E, UTM_N, UTMDatumZone, LatDegree, LongDegree, SRS, LocationUncertaintyStatement, LocationUncertaintyCode, LocationUncertaintyRadius, DrillerTotalDepth, DepthReferencePoint, LengthUnits, WellBoreShape, TrueVerticalDepth, ElevationKB, ElevationDF, ElevationGL, FormationTD, BitDiameterCollar, BitDiameterTD, DiameterUnits, RelatedResource, Notes, CasingLogger, CasingBottomDepthDriller, CasingTopDepth, CasingPipeDiameter, CasingWeight, CasingWeightUnits, CasingThickness and InformationSource.

Energy capacity data and map are from the California Energy Commission. Map depicts geothermal energy capacity by county. Unshaded counties had no geothermal energy capacity. Data is from 2022 and is current as of May 14, 2024. Projection: NAD 1983 (2011) California (Teale) Albers (Meters). For more information, contact John Hingtgen at (916) 510-9747 or Jessica Lin at (415) 990-8392.

This dataset is a compilation of electrical power production data (from geothermal power plants) in California, compiled from the Existing Electric Generating Units in the United States, 2005 (http://www.eia.doe.gov/cneaf/electricity/page/eia860.html). The data are available in the following formats: web feature service, web map service, ESRI Service Endpoint, and an Excel workbook for download. The workbook contains 4 worksheets, including information about the template with notes related to revisions of the template, resource provider information, the data, and a field list (data mapping view). This resource was provided by the Arizona Geological Survey and made available for distribution through the National Geothermal Data System.

Online interactive map service for wells in California. Select by API, latitude/longitude, PLSS, oil/gas field.

The California Department of Conservation, Division of Oil, Gas and Geothermal Resources publishes a GIS feature class of well locations and its associated records across the state for use by the public. Data provided are projected in Teal Albers California North American Datum of 1983 for shapefiles and WGS84 Web Mercator projection for web feature service. Well Attributes include API Number, Operator Well Number, Well Status, Well Type, Operator Code, Operator Name, Lease Name, Field Name, Area Name, District, County, Section, Township, Range, Base Meridian, Latitude, Longitude, Elevation, Total Depth, Redrill Footage, Redrill Cancel Flag, Location Description, Comments, GIS Source, Dry Hole, Confidential Well, Directionally Drilled, Hydraulically Fractured, BLM Well, EPA Well, Spud Date, Completion Date, Abandoned Date.Well location values were collected using a submeter-accurate gps receiver (i.e., Trimble GeoXT). Some of the data provided herein are also displayed in the Division's WellFinder application (http://maps.conservation.ca.gov/doggr/index.html).

© California Department of Conservation, Division of Oil, Gas and Geothermal Resources This layer is sourced from spatialservices.conservation.ca.gov.

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