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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 legacy user interface will continue to function for several weeks. However, this user interface only serves WQX2.2 profiles, which do NOT contain USGS data added after March 11, 2024.

WQP Home >  Providers >  STORET >  CEDEN >  CEDEN-06_SOMIS

Arroyo Las Posas OffRoad (CEDEN-06_SOMIS) site data in the Water Quality Portal

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

This river/stream intermittent site, maintained by the California State Water Resources Control Board (identifier CEDEN), has the name "Arroyo Las Posas OffRoad" and has the identifier CEDEN-06_SOMIS. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)18070103.

This site is located in Ventura County County, California at 34.2540000000 degrees latitude and -118.9930000000 degrees longitude using the datum WGS84. No horizontal location accuracy metadata is available. This site is at an elevation of 0 m No vertical location accuracy metadata is available.

To download the metadata about this site along with water quality data, go to the Portal Page and enter "CEDEN-06_SOMIS" 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*
Nutrient 2008 - 2015
Organics, Other 2010 - 2014
Organics, PCBs 2014 - 2014
Organics, Pesticide 2008 - 2015
Physical 2008 - 2015
*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 CEDEN
OrganizationFormalName California State Water Resources Control Board
MonitoringLocationIdentifier CEDEN-06_SOMIS
MonitoringLocationName Arroyo Las Posas OffRoad
MonitoringLocationTypeName River/Stream Intermittent
MonitoringLocationDescriptionText Arroyo Las Posas OffRoad
HUCEightDigitCode 18070103
LatitudeMeasure 34.2540000000
LongitudeMeasure -118.9930000000
HorizontalCollectionMethodName GPS-Unspecified
HorizontalCoordinateReferenceSystemDatumName WGS84
VerticalMeasure/MeasureValue 0
VerticalMeasure/MeasureUnitCode m
VerticalCollectionMethodName Other
VerticalCoordinateReferenceSystemDatumName UNKWN
CountryCode US
StateCode 06
CountyCode 111
ProviderName STORET