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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 >  MDE_TMDL >  MDE_TMDL-TP23

Lower Potomac River (MDE_TMDL-TP23) site data in the Water Quality Portal

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

This estuary site, maintained by the TMDL Technical Development Program (identifier MDE_TMDL), has the name "Lower Potomac River" and has the identifier MDE_TMDL-TP23. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)02070011.

This site is located in St. Mary's County County, Maryland at 38.1544500000 degrees latitude and -76.5972830000 degrees longitude using the datum NAD83. No horizontal location accuracy metadata is available.

To download the metadata about this site along with water quality data, go to the Portal Page and enter "MDE_TMDL-TP23" 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*
Not Assigned 2000 - 2000
Organics, Other 2000 - 2000
Organics, PCBs 2000 - 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 MDE_TMDL
OrganizationFormalName TMDL Technical Development Program
MonitoringLocationIdentifier MDE_TMDL-TP23
MonitoringLocationName Lower Potomac River
MonitoringLocationTypeName Estuary
HUCEightDigitCode 02070011
LatitudeMeasure 38.1544500000
LongitudeMeasure -76.5972830000
HorizontalCollectionMethodName GPS-Unspecified
HorizontalCoordinateReferenceSystemDatumName NAD83
CountryCode US
StateCode 24
CountyCode 037
ProviderName STORET