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.
Dissolved Oxygen in a stream may vary from 0 mg/l to 18 mg/l. Dissolved oxygen gets into the water by diffusion from the atmosphere, aeration of the water as it tumbles over falls and rapids, and as a waste product of photosynthesis.