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Maryland Real-Time Water Quality


NRTWQ Home >> Maryland >> Constituents

Constituents Measured or Computed Continuously in Maryland

Continuous measurements of constituents (water-quality parameters) can be obtained by direct measurement using sensors, or by indirect computation using models.

Below is a list of constituents continuously measured or computed by the USGS in Maryland. Click on a constituent for more detailed information, including a list of where it is measured or computed.

Constituent Name Units Criteria
Computed discharge cubic feet per second (cfs)
Dissolved oxygen milligrams per liter (mg/L) 5 mg/L
Escherichia coli bacteria colonies per 100 milliliters (cfu/100mL)
pH standard units (std units) 6.5 std units, 8.5 std units
Specific conductance at 25 degrees Celsius microsiemens per centimeter (uS/cm) 400 uS/cm
Suspended sediment milligrams per liter (mg/L)
Suspended sediment concentration, water, unfiltered, estimated by regression equation milligrams per liter (mg/L)
Total nitrogen, water, filtered, estimated by regression equation, milligrams per liter milligrams per liter as nitrogen (mg/L-N)
Total phosphorus milligrams per liter (mg/L)
Total phosphorus milligrams per liter as phosphorus (mg/L-P)
Turbidity, measured as NTU or FNU formazin nephelometric units (FNU) 150 FNU
Water temperature degrees Celsius (°C)