Chesapeake Bay Program Water Quality Database

The Water Quality Monitoring database is a compilation of data for 19
parameters at 49 mainbay and approximately 150 tributary stations for Maryland,
Virginia, and the District of Columbia with several state agencies and
universities sharing in the collection and analysis of these data. The program
was established as a long-term program of data collection and analysis to
establish baseline water quality conditions in the Bay and to monitor changes
in water quality conditions over time.

The program began in June, 1984 with stations sampled once each month during
the colder late fall and winter months and twice each month in the warmer
months. The collecting organizations coordinate the sampling times of their
stations, so that data for each sampling event represents a synoptic picture of
the mainbay at that point in time. The sampling frequency has changed over
time, and some stations have been deleted or added. Parameters sampled
include: temperature (WTEMP), dissolved oxygen (DO), conductivity (COND),
salinity (SALINITY), ph (pH), secchi depth (SECCHI), chlorophyll a (CHLA),
pheophytin (PHEO), silica, whole and filtered (SIW, SIF), total suspended
solids (TSS), total phosphorus (TP), total dissolved phosphorus (TDP),
particulate phosphorus (PP), orthophosphate whole and filtered (PO4W, PO4F),
total dissolved nitrogen (TDN), total Kjeldahl nitrogen whole and filtered
(TKNW, TKNF), nitrite plus nitrate whole and filtered (NO23W, NO23F), nitrite
whole and filtered (NO2W, NO2F), nitrate whole and filtered (NO3W, NO3F),
ammonium whole and filtered (NH4W, NH4F), particulate organic nitrogen (PN),

total organic carbon (TOC), dissolved organic carbon (DOC), particulate organic
carbon (POC). Some parameters have been dropped or replaced over time, and
several additional parameters are available for the tributary stations.

See the station listing at www.chesapeakebay.net/data/index.htm

This database was created to store grant deliverable data and associated
tributary data collected as part of the Chesapeake Bay Program water quality
monitoring program. These data are used to guide environmental decisions and to
monitor responses of the system to management actions.