Meter and non meter fall
METER AND NON-METER FALLS The falls may be divided into following two types: 1. Meter falls 2. Non-meter falls. 1. Meter Falls. The falls which can be used to measure the discharge flowing over them, are known as meter falls. Such falls must have broad crest so that the discharge coefficient remains constant under variable head. Glacis type falls are most suitable as meter falls. If section of the channel at the site of the fall has to be flumed. From economic considerations, smooth U/S transition. Should be provided to avoid turbulences and also to maintain accurate stage-discharge relationship. 2. Non-meter Falls. The falls which cannot be use to measure the discharge passing through them, are known as non-meter falls. Vertical drop falls cannot be used as meter falls. Some vacuum is developed under the nappe of falling water, which causes non-uniform flow conditions.