Water temperature, salinity (computed from specific conductance data), turbidity, dissolved oxygen, pH, and water level data were collected by a continuously recording water quality monitor located in the Rhode River, at the Smithsonian Institution's pier near Annapolis, Md., from April 1970 through December 1973. Data, as presented in this report, consist of daily maximum and minimum values summarized by week to give weekly averages and extremes.
Temperatures showed an overall range from 0.7 to 32.6°C. The water temperature data indicate successively warmer winters. Salinity ranged from
1.05 to 14.03 parts per thousand. In June 1972, salinity dropped markedly as fresh water from tropical storm Agnes entered the Rhode River from Chesapeake Bay. Most of the fresh water entering upper Chesapeake Bay as a result of tropical storm Agnes came from the Susquehanna River. Turbidity was usually low, averaging about 14 Jackson Turbidity Units; however, during spring and early summer of 1972, values averaged about 23 Jackson Turbidity Units. This increase in turbidity was due to the high Susquehanna River flows during that period. Extremes of turbidity ranged from about 5 to 80 Jackson Turbidity Units.
Dissolved oxygen ranged from 0.0 to 19.8 milligrams per litre. Large daily changes in oxygen indicated a high state of biological metabolism. Values of pH ranged from 6.8 to 10.1 and daily changes coincided with oxygen changes. Tide-dominated water levels had an overall range of 5.9 feet (1.8 metres) and a mean tidal range of 1.5 feet (0.46 metres).
