Volumetric method
A direct method of measuring the discharge (flow rate) of a river. This method has a small error (<1%) but it is only applicable for discharge measurements of small streams (with low discharge), usually of spring outflows in which the outflow occurs as a concentrated stream or in places where all flowing water can be captured. The measurement is done in a simple and uncomplicated way. It is enough to place a container of a known volume under the water outflow to capture all the outflowing water and measure the time in which the container fills with water.