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.

The USGS National Hydrography Dataset (NHD) downloadable data collection from The National Map (TNM) is a comprehensive set of digital spatial data that encodes information about naturally occurring and constructed bodies of surface water (lakes, ponds, and reservoirs), paths through which water flows (canals, ditches, streams, and rivers), and related entities such as point features (springs, wells, stream gages, and dams). The information encoded about these features includes classification and other characteristics, delineation, geographic name, position and related measures, a "reach code" through which other information can be related to the NHD, and the direction of water flow. The network of reach codes delineating water and transported material flow allows users to trace movement in upstream and downstream directions. In addition to this geographic information, the dataset contains metadata that supports the exchange of future updates and improvements to the data. The NHD supports many applications, such as making maps, geocoding observations, flow modeling, data maintenance, and stewardship. For additional information on NHD, go to https://www.usgs.gov/core-science-systems/ngp/national-hydrography.

DWR was the steward for NHD and Watershed Boundary Dataset (WBD) in California. We worked with other organizations to edit and improve NHD and WBD, using the business rules for California. California's NHD improvements were sent to USGS for incorporation into the national database. The most up-to-date products are accessible from the USGS website. Please note that the California portion of the National Hydrography Dataset is appropriate for use at the 1:24,000 scale.

For additional derivative products and resources, including the major features in geopackage format, please go to this page: https://data.cnra.ca.gov/dataset/nhd-major-features Archives of previous statewide extracts of the NHD going back to 2018 may be found at https://data.cnra.ca.gov/dataset/nhd-archive.

In September 2022, USGS officially notified DWR that the NHD would become static as USGS resources will be devoted to the transition to the new 3D Hydrography Program (3DHP). 3DHP will consist of LiDAR-derived hydrography at a higher resolution than NHD. Upon completion, 3DHP data will be easier to maintain, based on a modern data model and architecture, and better meet the requirements of users that were documented in the Hydrography Requirements and Benefits Study (2016). The initial releases of 3DHP include NHD data cross-walked into the 3DHP data model. It will take several years for the 3DHP to be built out for California. Please refer to the resources on this page for more information.

The FINAL,STATIC version of the National Hydrography Dataset for California was published for download by USGS on December 27, 2023. This dataset can no longer be edited by the state stewards. The next generation of national hydrography data is the USGS 3D Hydrography Program (3DHP).

Questions about the California stewardship of these datasets may be directed to nhd_stewardship@water.ca.gov.

The California State Lands Commission (CSLC) was created by the California Legislature in 1938 and given the authority and responsibility to manage certain public lands within the state. The public lands under the Commission’s jurisdiction are of two distinct types—sovereign lands acquired upon California’s admission into the Union in 1850; and certain federally granted lands including school lands, and swamp and overflowed lands. For purposes of this GIS data, sovereign lands are considered to be further divided into two general categories—fixed-boundary sovereign lands and ambulatory-boundary sovereign lands. The following lands are included in this data: Portions of the ambulatory-boundary for state sovereign lands at a specific point in time, for portions of the San Joaquin River. NOT INCLUDED IN THIS DATA: School lands: These are what remains of nearly 5.5 million acres throughout the state originally granted to California by Congress in 1853 to benefit public education. Fixed-boundary sovereign lands: These are sovereign, public trust lands having fixed boundaries as the result of land exchanges, boundary line agreements or court orders. Swamps and overflowed lands: These are what remain of federal lands granted to California by Congress in 1850 to encourage reclamation and development of agricultural lands. ALSO NOT INCLUDED IN THIS DATA: Ownership details within the U.S. Government meanders of Owens Lake. THIS DATA SUPERSEDES all previously published GIS information with respect to the above described state-owned lands under the jurisdiction of the CSLC.

This geologic map database is comprised of new geologic mapping, at a 1:24,000 scale, along the southern Bartlett Springs fault in the northern California Coast Ranges. The map covers an area of 258 square miles in Lake, Napa, Colusa, and Yolo counties, work was undertaken between 2016 and 2021, and supported by the USGS National Cooperative Geologic Map Program. This geodatabase contains the most up-to-date and highest resolution mapping in the region. Results and observations reported here help elucidate the geologic deformational history, as well as relationships between active older and active structures. Please consult the map pamphlet and description of map units for a detailed presentation and interpretation of data and discussion of results. The report and geodatabase contain two plates including the geologic map as well as a correlation of map units, four geologic cross sections, six microseismic cross sections, and a microseismicity fault map.

https://www.loc.gov/resource/g4360.ct007805TitleA new map of the States of California and Nevada, exhibiting the rivers, lakes, bays, and islands, with the principal towns, roads, railroads, and transit routes to the silver mining districts; also meridian, standard, range and township lines as established; to which is added the county boundaries and United States land districts.NamesRansom, Leander, 1800-1874.Doolittle, A. J., joint author.Baker, Geo. H. (George Holbrook), 1827-1906.Holt, Warren.Created / Published[San Francisco] W. Holt, 1867.

Percent of each freshwater ecoregion’s area covered with lakes and man-made reservoirs.

We calculated the percentage of the ecoregion that is covered by lakes and reservoirs using lake and reservoir polygons from the Global Lakes and Wetlands Database (GLWD) (Lehner and Döll 2004). This database represents the best available source for lakes and wetlands on a global scale (1:1 to 1:3 million resolution). The GLWD contains shoreline polygons of the 3,067 largest lakes (surface area greater than or equal to 50 km2) and 654 largest reservoirs (storage capacity greater than or equal to 0.5 km3) worldwide, as well as shoreline polygons of approximately 250,000 smaller lakes, reservoirs, and rivers (surface area greater than or equal to 0.1 km2). For our calculations, only lake and reservoir polygons were used. It was not possible to separate natural lake polygons from reservoirs.

These data were derived by The Nature Conservancy, and were displayed in a map published in The Atlas of Global Conservation (Hoekstra et al., University of California Press, 2010). More information at http://nature.org/atlas.

Data derived from:

Lehner, B., and P. Döll. 2004. Development and validation of a global database of lakes, reservoirs and wetlands. Journal of Hydrology 296: 1–22.

These data were derived by The Nature Conservancy, and were displayed in a map published in The Atlas of Global Conservation (Hoekstra et al., University of California Press, 2010). More information at http://nature.org/atlas.

For more about The Atlas of Global Conservation check out the web map (which includes links to download spatial data and view metadata) at http://maps.tnc.org/globalmaps.html. You can also read more detail about the Atlas at http://www.nature.org/science-in-action/leading-with-science/conservation-atlas.xml, or buy the book at http://www.ucpress.edu/book.php?isbn=9780520262560

Medicine Lake, California Well Locations

description: This geologic map database for the El Mirage Lake area describes geologic materials for the dry lake, parts of the adjacent Shadow Mountains and Adobe Mountain, and much of the piedmont extending south from the lake upward toward the San Gabriel Mountains. This area lies within the western Mojave Desert of San Bernardino and Los Angeles Counties, southern California. The area is traversed by a few paved highways that service the community of El Mirage, and by numerous dirt roads that lead to outlying properties. An off-highway vehicle area established by the Bureau of Land Management encompasses the dry lake and much of the land north and east of the lake. The physiography of the area consists of the dry lake, flanking mud and sand flats and alluvial piedmonts, and a few sharp craggy mountains. This digital geologic map database, intended for use at 1:24,000- scale, describes and portrays the rock units and surficial deposits of the El Mirage Lake area. It was prepared as part of a water-resource assessments of the area, describing and interpreting surface geology that provides information to help understand distribution and extent of deeper groundwater-bearing units. The area mapped covers the Shadow Mountains SE and parts of the Shadow Mountains, Adobe Mountain, and El Mirage 7.5-minute quadrangles. The map database includes detailed geology of surface and bedrock deposits, which represent a significant update from previous bedrock geologic maps by Dibblee (1960) and Troxel and Gunderson (1970), and the surficial geologic map of Ponti and Burke (1980); it incorporates a fringe of the detailed bedrock mapping in the Shadow Mountains by Martin (1992).; abstract: This geologic map database for the El Mirage Lake area describes geologic materials for the dry lake, parts of the adjacent Shadow Mountains and Adobe Mountain, and much of the piedmont extending south from the lake upward toward the San Gabriel Mountains. This area lies within the western Mojave Desert of San Bernardino and Los Angeles Counties, southern California. The area is traversed by a few paved highways that service the community of El Mirage, and by numerous dirt roads that lead to outlying properties. An off-highway vehicle area established by the Bureau of Land Management encompasses the dry lake and much of the land north and east of the lake. The physiography of the area consists of the dry lake, flanking mud and sand flats and alluvial piedmonts, and a few sharp craggy mountains. This digital geologic map database, intended for use at 1:24,000- scale, describes and portrays the rock units and surficial deposits of the El Mirage Lake area. It was prepared as part of a water-resource assessments of the area, describing and interpreting surface geology that provides information to help understand distribution and extent of deeper groundwater-bearing units. The area mapped covers the Shadow Mountains SE and parts of the Shadow Mountains, Adobe Mountain, and El Mirage 7.5-minute quadrangles. The map database includes detailed geology of surface and bedrock deposits, which represent a significant update from previous bedrock geologic maps by Dibblee (1960) and Troxel and Gunderson (1970), and the surficial geologic map of Ponti and Burke (1980); it incorporates a fringe of the detailed bedrock mapping in the Shadow Mountains by Martin (1992).

State Water Resources Control Board Division of Water Quality staff have developed this map to graphically display the waterbodies assessed in the 2018 California Integrated Report. This map contains waterbodies assessed for 305(b) categorization, including those placed on the 303(d) list of impaired waters.Map Layers and Table:2018 Integrated Report Streams, Rivers, and Beaches: Spatial representation of the assessed linear waterbodies in California.2018 Integrated Report Lakes, Bays, and Reservoirs: Spatial representation of the non-linear (polygon) waterbodies in California. The layers can also be accessed here: https://gispublic.waterboards.ca.gov/portalserver/rest/services/Hosted/CA_2018_Integrated_Report_Assessed_Lines_and_Polys/FeatureServerHow to Use the Map:Navigate to your point of interest by either using the search bar in the upper left-hand corner of the map or by zooming in on the map. You may enter a waterbody name or address into the search bar. Click on a waterbody of interest, such as a river, lake, or beach, and a pop-up box will appear with a summary of the pollutant assessments conducted for that waterbody. Select the ellipsis ("...") in a pop-up window or the layers to view the attribute table. This table can be further filtered and exported in a tabular format. Click on the layers icon in the upper right hand corner to toggle map layers on and off.Click on the filter button in the upper right corner to filter for a specific Regional Board and to select for 303(d) listed waterbodies only. Note, this should be done for both layers.More details on each waterbody can be found by scrolling to the bottom of a waterbody pop-up and selecting “Waterbody Fact Sheet- More information”.Pop Up Description:WBID: Unique identifier for each waterbody used in the Integrated Report. Waterbody Name: Name of the mapped waterbody assessed for the Integrated Report. Waterbody Type: Type of water (Coastal & Bay Shoreline, Freshwater Wetland, Tidal Wetland, Saline Lake, River & Stream, Ocean, Lake and Reservoir, Estuary, and Bay & Harbor).Regional Board: Which Regional Water Quality Control Board has jurisdiction over the waterbody. Waterbody Condition Category: Integrated Report 305(b) Category for the waterbody.Waterbody Listing Status: If the waterbody has been placed on the 303(d) list as impaired for one or more pollutant, it will be identified as "Listed". If it was assessed for one or more pollutant and not determined to be impaired, it will be identified as "Not Listed". Listed Pollutants: Pollutants identified as impairing the waterbody's support of beneficial uses. The Decision ID is included in parentheses. Listings Addressed by a TMDL: Pollutant impairments in the waterbody being addressed by an adopted Total Maximum Daily Load (TMDL)Listings Addressed by Action other than TMDL: Pollutant impairments in the waterbody being addressed by actions other than a TMDL. These may also be referred to as Category “4b” decisions.Pollutants Assessed, Not Listed: Pollutant assessments that did not result in a 303(d) impairment decision for the waterbody.Waterbody Fact Sheet: Link to the Waterbody Fact Sheet for the waterbody, which includes waterbody/pollutant assessment information. For additional data and information about the 2018 Integrated Report assessments, please visit our Data Download page: (coming soon!)For more information about the Integrated Report (the 305(b) Report and the 303(d) List), how it is created, or how this information is used, please see the program webpage: https://www.waterboards.ca.gov/water_issues/programs/water_quality_assessment/Please contact the SWRCB Water Quality Assessment Program with any questions, at WQAssessment@waterboards.ca.gov. Origin Date: July 2, 2021Last edited: July 28, 2021

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 ...

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, ...

NOTICE TO PROVISIONAL 2023 LAND USE DATA USERS: Please note that on December 6, 2024 the Department of Water Resources (DWR) published the Provisional 2023 Statewide Crop Mapping dataset. The link for the shapefile format of the data mistakenly linked to the wrong dataset. The link was updated with the appropriate data on January 27, 2025. If you downloaded the Provisional 2023 Statewide Crop Mapping dataset in shapefile format between December 6, 2024 and January 27, we encourage you to redownload the data. The Map Service and Geodatabase formats were correct as posted on December 06, 2024.

Thank you for your interest in DWR land use datasets.

The California Department of Water Resources (DWR) has been collecting land use data throughout the state and using it to develop agricultural water use estimates for statewide and regional planning purposes, including water use projections, water use efficiency evaluations, groundwater model developments, climate change mitigation and adaptations, and water transfers. These data are essential for regional analysis and decision making, which has become increasingly important as DWR and other state agencies seek to address resource management issues, regulatory compliances, environmental impacts, ecosystem services, urban and economic development, and other issues. Increased availability of digital satellite imagery, aerial photography, and new analytical tools make remote sensing-based land use surveys possible at a field scale that is comparable to that of DWR’s historical on the ground field surveys. Current technologies allow accurate large-scale crop and land use identifications to be performed at desired time increments and make possible more frequent and comprehensive statewide land use information. Responding to this need, DWR sought expertise and support for identifying crop types and other land uses and quantifying crop acreages statewide using remotely sensed imagery and associated analytical techniques. Currently, Statewide Crop Maps are available for the Water Years 2014, 2016, 2018- 2022 and PROVISIONALLY for 2023.

Historic County Land Use Surveys spanning 1986 - 2015 may also be accessed using the CADWR Land Use Data Viewer: https://gis.water.ca.gov/app/CADWRLandUseViewer.

For Regional Land Use Surveys follow: https://data.cnra.ca.gov/dataset/region-land-use-surveys.

For County Land Use Surveys follow: https://data.cnra.ca.gov/dataset/county-land-use-surveys.

For a collection of ArcGIS Web Applications that provide information on the DWR Land Use Program and our data products in various formats, visit the DWR Land Use Gallery: https://storymaps.arcgis.com/collections/dd14ceff7d754e85ab9c7ec84fb8790a.

Recommended citation for DWR land use data: California Department of Water Resources. (Water Year for the data). Statewide Crop Mapping—California Natural Resources Agency Open Data. Retrieved “Month Day, YEAR,” from https://data.cnra.ca.gov/dataset/statewide-crop-mapping.

This dataset contains shapefile boundaries for CA State, counties and places from the US Census Bureau's 2023 MAF/TIGER database. Current geography in the 2023 TIGER/Line Shapefiles generally reflects the boundaries of governmental units in effect as of January 1, 2023.

Geologic Map Of California Walker Lake Sheet

This dataset depicts Right of Ways for private developments in the Town of Mammoth Lakes, CA

An isostatic residual gravity map of the Big Bear Lake 100,000 scale quadrangle, California was prepared and then this data set used with other information to compute the configuration of several ground water basins. Basin thickness maps were then prepared.

NOTICE TO PROVISIONAL 2023 LAND USE DATA USERS: Please note that on December 6, 2024 the Department of Water Resources (DWR) published the Provisional 2023 Statewide Crop Mapping dataset. The link for the shapefile format of the data mistakenly linked to the wrong dataset. The link was updated with the appropriate data on January 27, 2025. If you downloaded the Provisional 2023 Statewide Crop Mapping dataset in shapefile format between December 6, 2024 and January 27, we encourage you to redownload the data. The Map Service and Geodatabase formats were correct as posted on December 06, 2024.

Thank you for your interest in DWR land use datasets.

The California Department of Water Resources (DWR) has been collecting land use data throughout the state and using it to develop agricultural water use estimates for statewide and regional planning purposes, including water use projections, water use efficiency evaluations, groundwater model developments, climate change mitigation and adaptations, and water transfers. These data are essential for regional analysis and decision making, which has become increasingly important as DWR and other state agencies seek to address resource management issues, regulatory compliances, environmental impacts, ecosystem services, urban and economic development, and other issues. Increased availability of digital satellite imagery, aerial photography, and new analytical tools make remote sensing-based land use surveys possible at a field scale that is comparable to that of DWR’s historical on the ground field surveys. Current technologies allow accurate large-scale crop and land use identifications to be performed at desired time increments and make possible more frequent and comprehensive statewide land use information. Responding to this need, DWR sought expertise and support for identifying crop types and other land uses and quantifying crop acreages statewide using remotely sensed imagery and associated analytical techniques. Currently, Statewide Crop Maps are available for the Water Years 2014, 2016, 2018- 2022 and PROVISIONALLY for 2023.

Historic County Land Use Surveys spanning 1986 - 2015 may also be accessed using the CADWR Land Use Data Viewer: https://gis.water.ca.gov/app/CADWRLandUseViewer.

For Regional Land Use Surveys follow: https://data.cnra.ca.gov/dataset/region-land-use-surveys.

For County Land Use Surveys follow: https://data.cnra.ca.gov/dataset/county-land-use-surveys.

For a collection of ArcGIS Web Applications that provide information on the DWR Land Use Program and our data products in various formats, visit the DWR Land Use Gallery: https://storymaps.arcgis.com/collections/dd14ceff7d754e85ab9c7ec84fb8790a.

Recommended citation for DWR land use data: California Department of Water Resources. (Water Year for the data). Statewide Crop Mapping—California Natural Resources Agency Open Data. Retrieved “Month Day, YEAR,” from https://data.cnra.ca.gov/dataset/statewide-crop-mapping.

Abstract not available.

Geologic map of the Lake Tahoe Basin, California and Nevada, Scale 1:100,000. This map is available for purchase by contacting the California Geological Survey. For more information see links provided.