The EMAP-Estuaries Station Location and Station Visit data sets
contain geographical and statistical information on all stations in the
Virginian Province. The Base stations were stations which were
randomly located, based on a nationwide grid. If a BASE station
also met the criteria for another station classification, then other
monitoring activities were included in the suite of samples
expected for the station. The unique geographic coordinates of a
site are given. Visit information includes the date of the sampling
visit and the water depth at the time of the visit.
Some variables present descriptive geographic information.
The two (2) character mailing code for the State inside
whose geopolitical boundaries the station lies is reported.
The Water Body System indicates the large body of water or
watershed in which the station site is located. The Estuary
defines the specific river, bay, creek or other small water
body in which the station is located.
Other variables are present for statistical purposes. The Water
Body Strata indicates a broad water body category assigned to a
station. These include Large Estuary (L), Small Estuary or
Tidal River (O) or large Tidal River (TR). These categories
serve to aggregate and/or segregate the data for statistical
purposes. A Station Statistical Area is calculated for each
station for weighting the data collected at a station on a
parameter basis. The value is the actual area represented by a
The Environmental Monitoring and Assessment Program (EMAP) was designed to periodically estimate the status and trends of the Nation's ecological resources on a regional basis. EMAP provides a strategy to identify and bound the extent, magnitude and location of environmental degradation and improvement on a regional scale.
The Station Location and Station Visit data sets provide statistical and geographical characterization of all types of stations sampled in the estuaries of the Virginian Province.