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New WQX 3.0 profiles are available at waterqualitydata.us/beta/. These profiles will contain recent USGS data added since March 11, 2024, which marks the beginning of limited accessibility for USGS data. Read more about the 3.0 profiles and associated changes here. This user interface only serves WQX2.2 profiles, which do NOT contain USGS data added after March 11, 2024.

WQP Home >  Providers >  NWIS >  USGS-CA >  USGS-380502121350301

WEBB TRACT EAST POND NR TERMINOUS CA (USGS-380502121350301) site data in the Water Quality Portal

Data Provider: NWIS (Learn more about Water Quality Portal Data Providers)

This lake, reservoir, impoundment site, maintained by the USGS California Water Science Center (identifier USGS-CA), has the name "WEBB TRACT EAST POND NR TERMINOUS CA" and has the identifier USGS-380502121350301. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)18040003. See more details of this site the the USGS NWIS Web page for this site.

This site is located in Contra Costa County County, California at 38.08395000000000 degrees latitude and -121.5842694000000 degrees longitude using the datum NAD83. The horizontal location collection method was "Mapping grade GPS unit (handheld accuracy range 12 to 40 ft)" and the accuracy is .5 seconds. The source map scale is 1:24000. This site is at an elevation of -12 feet and the accuracy of the elevation measurement, collected using the method "Interpolated from Digital Elevation Model" is 1.6 feet. The vertical coordinate reference system is NAVD88.

To download the metadata about this site along with water quality data, go to the Portal Page and enter "USGS-380502121350301" into the "Site ID" box under Site Parameters

What other monitoring locations are upstream or downstream from this one?

Upstream and downstream locations

This map shows all Water Quality Portal stations that are 10 miles upstream (dashed dark blue) and 10 miles downstream (solid light blue) of this monitoring location (indicated by the large blue circle). The upstream and downstream functionality is provided by the Network Linked Data Index.

When were data collected at this location?

Periods of record for data characteristic groups

For a more detailed breakdown of data, go to the Monitoring Report at the EPA How's My Waterway Application
Characteristic Group Date Range*
Biological, Algae, Cyanobacteria 2022 - 2022
Biological, Algae, Phytoplankton, Photosynthetic Pigments 2022 - 2022
Information 2022 - 2022
Inorganics, Major, Metals 2022 - 2022
Inorganics, Major, Non-metals 2022 - 2022
Inorganics, Minor, Metals 2022 - 2022
Inorganics, Minor, Non-metals 2022 - 2022
Nutrient 2022 - 2022
Organics, Other 2022 - 2023
Organics, PCBs 2022 - 2023
Organics, Pesticide 2022 - 2023
PFAS,Perfluorinated Alkyl Substance 2022 - 2023
Physical 2022 - 2023
*Date ranges may contain gap years

What other information is available for this location?

Detailed Metadata

For the definitions of the metadata elements, please go to the Water Quality Portal user guide

Location Metadata Value
OrganizationIdentifier USGS-CA
OrganizationFormalName USGS California Water Science Center
MonitoringLocationIdentifier USGS-380502121350301
MonitoringLocationName WEBB TRACT EAST POND NR TERMINOUS CA
MonitoringLocationTypeName Lake, Reservoir, Impoundment
HUCEightDigitCode 18040003
LatitudeMeasure 38.08395000000000
LongitudeMeasure -121.5842694000000
SourceMapScaleNumeric 24000
HorizontalAccuracyMeasure/MeasureValue .5
HorizontalAccuracyMeasure/MeasureUnitCode seconds
HorizontalCollectionMethodName Mapping grade GPS unit (handheld accuracy range 12 to 40 ft)
HorizontalCoordinateReferenceSystemDatumName NAD83
VerticalMeasure/MeasureValue -12
VerticalMeasure/MeasureUnitCode feet
VerticalAccuracyMeasure/MeasureValue 1.6
VerticalAccuracyMeasure/MeasureUnitCode feet
VerticalCollectionMethodName Interpolated from Digital Elevation Model
VerticalCoordinateReferenceSystemDatumName NAVD88
CountryCode US
StateCode 06
CountyCode 013
ProviderName NWIS