River or stream flow is the amount of water that moves over a designated point in a fixed period of time. This measurement is usually expressed in cubic feet per second (ft 3/s).

The flow of a river is directly related to the amount of water moving off of the watershed into the stream channel. It is a function of water volume and velocity, and is important because it has an impact on organisms living in the stream, as well as the overall water quality. Flow can affect the river’s ability to assimilate pollutants; larger, swiftly-moving streams and rivers can receive pollutants with a diminished negative effect. Smaller rivers with low flow have less of a capacity to dilute and degrade potentially harmful pollutants.

Look along the stream bank for clues as to where the water flows most of the year. Estimate whether the stream is currently at a high, average, or low level compared to the year-round estimate.

You may also want to find out if there is a US Geological Survey stream flow data logger located on your river and near your monitoring site. Information on average flows would provide interesting comparative data to your estimate.

For a more accurate calculation of relative flow, click HERE