For the municipality of the same name in Gloucester County, see Monroe Township, Gloucester County, New Jersey.
How to measure dissolved oxygen. Dissolved oxygen is measured using a dissolved oxygen meter. The best method is to take the measurement in the field at the same time each day because DO concentrations can vary throughout a 24 hour period.issolved oxygen (DO) is a measure of the quantity of free oxygen molecules in water.
A small amount of oxygen, up to about ten molecules of oxygen per million of water, is actually dissolved in water. Oxygen enters a stream mainly from the atmosphere and, in areas where ground-water discharge into streams is a large portion of streamflow, from groundwater discharge.n summer and fall, when the water temperature is high, the dissolved-oxygen concentration is low. Dissolved oxygen in surface water is used by all forms of aquatic life; therefore, this constituent typically is measured to assess the health of lakes and streams.