To determine the power available at a site, head and flow measurements must be taken. Flow is the rate at which water moves, measured in liters per minute (I/m) or gallons per minute (gpm). This can be measured by channeling the water into a pipeline, then into a container of a known volume, noting the time it takes to do so. Head can be measured by using a transit, by siting along a level, or by using a pressure gauge at the end of the pipeline. It is important to keep in mind that output can only be accurately determined if head and flow measurements are made correctly, so care should be taken during this process.
|FLOW Litres/Min (GALLONS/MIN)|
|Head Metres (Feet)||40 (10)||80 (20)||150 (40)||300 (75)||400 (100)|