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KNOWLES MARSH, MD (USGS-390257076474501) 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 Virginia Water Science Center (identifier USGS-VA), has the name "KNOWLES MARSH, MD" and has the identifier USGS-390257076474501. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)02060006. See more details of this site the the USGS NWIS Web page for this site.

This site is located in Prince George's County County, Maryland at 39.04916667000000 degrees latitude and -76.7958333000000 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 1 seconds. The source map scale is 1:24000.

To download the metadata about this site along with water quality data, go to the Portal Page and enter "USGS-390257076474501" 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 2002 - 2003
Physical 2002 - 2003
*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-VA
OrganizationFormalName USGS Virginia Water Science Center
MonitoringLocationIdentifier USGS-390257076474501
MonitoringLocationName KNOWLES MARSH, MD
MonitoringLocationTypeName Lake, Reservoir, Impoundment
HUCEightDigitCode 02060006
LatitudeMeasure 39.04916667000000
LongitudeMeasure -76.7958333000000
SourceMapScaleNumeric 24000
HorizontalAccuracyMeasure/MeasureValue 1
HorizontalAccuracyMeasure/MeasureUnitCode seconds
HorizontalCollectionMethodName Mapping grade GPS unit (handheld accuracy range 12 to 40 ft)
HorizontalCoordinateReferenceSystemDatumName NAD83
CountryCode US
StateCode 24
CountyCode 033
ProviderName NWIS