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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 >  STORET >  11NPSWRD_WQX >  11NPSWRD_WQX-THST_L1_4530

Thomas Stone Pond near Port Tobacco, MD (11NPSWRD_WQX-THST_L1_4530) site data in the Water Quality Portal

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

This reservoir site, maintained by the National Park Service Water Resources Division (identifier 11NPSWRD_WQX), has the name "Thomas Stone Pond near Port Tobacco, MD" and has the identifier 11NPSWRD_WQX-THST_L1_4530. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)02070011.

This site is located in Charles County County, Maryland at 38.5308700000 degrees latitude and -77.0357800000 degrees longitude using the datum NAD27. No horizontal location accuracy metadata is available. This site is at an elevation of 158 ft 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 "11NPSWRD_WQX-THST_L1_4530" 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*
Inorganics, Major, Non-metals 1999 - 2000
Microbiological 1999 - 2000
Nutrient 1999 - 2000
Physical 1999 - 2000
*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 11NPSWRD_WQX
OrganizationFormalName National Park Service Water Resources Division
MonitoringLocationIdentifier 11NPSWRD_WQX-THST_L1_4530
MonitoringLocationName Thomas Stone Pond near Port Tobacco, MD
MonitoringLocationTypeName Reservoir
MonitoringLocationDescriptionText At north end of visitor's parking area, approximately 900 ft east of the Thomas Stone home and 1.5 mi northwest of Port Tobacco, MD. Water samples collected at this site monitor the water quality of a pond which is located near the visitor parking area and may be the most encountered source of water by park visitors.
HUCEightDigitCode 02070011
LatitudeMeasure 38.5308700000
LongitudeMeasure -77.0357800000
SourceMapScaleNumeric 24000
HorizontalCollectionMethodName Interpolation-Map
HorizontalCoordinateReferenceSystemDatumName NAD27
VerticalMeasure/MeasureValue 158
VerticalMeasure/MeasureUnitCode ft
VerticalCollectionMethodName Topographic Map Interpolation
VerticalCoordinateReferenceSystemDatumName NGVD29
CountryCode US
StateCode 24
CountyCode 017
ProviderName STORET