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WQP Home >  Providers >  STORET >  21FLSEM >  21FLSEM-MRK

Lake Markham (21FLSEM-MRK) site data in the Water Quality Portal

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

This lake site, maintained by the Seminole County (Florida) (identifier 21FLSEM), has the name "Lake Markham" and has the identifier 21FLSEM-MRK. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)03080101.

This site is located in Seminole County County, Florida at 28.7979000 degrees latitude and -81.3941000 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 "21FLSEM-MRK" 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.

Leaflet USGS The National Map: National Boundaries Dataset, 3DEP Elevation Program, Geographic Names Information System, National Hydrography Dataset, National Land Cover Database, National Structures Dataset, and National Transportation Dataset; USGS Global Ecosystems; U.S. Census Bureau TIGER/Line data; USFS Road data; Natural Earth Data; U.S. Department of State HIU; NOAA National Centers for Environmental Information. Data refreshed February, 2025.

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 1998 - 2009
Information 1998 - 2009
Inorganics, Major, Metals 1998 - 2003
Inorganics, Minor, Metals 1998 - 2003
Inorganics, Minor, Non-metals 1999 - 2003
Microbiological 1998 - 2009
Nutrient 1998 - 2009
Physical 1998 - 2009
*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 21FLSEM
OrganizationFormalName Seminole County (Florida)
MonitoringLocationIdentifier 21FLSEM-MRK
MonitoringLocationName Lake Markham
MonitoringLocationTypeName Lake
MonitoringLocationDescriptionText Lake Markham
HUCEightDigitCode 03080101
LatitudeMeasure 28.7979000
LongitudeMeasure -81.3941000
HorizontalCollectionMethodName GPS Code (Pseudo Range) Differential
HorizontalCoordinateReferenceSystemDatumName NAD83
CountryCode US
StateCode 12
CountyCode 117
ProviderName STORET