The tailwater at a culvert is the depth of water at the downstream end of the culvert, as measured from the downstream invert of the culvert. The tailwater must be known or estimated prior to performing the culvert hydraulic calculations. There are various methods to estimate the tailwater at a culvert.
How do you measure tailwater depth?
Tailwater is defined as the depth of flow in a channel immediately downstream of a drainage facility.
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The calculation process is:
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The calculation process is:
- Choose a depth of flow.
- Calculate the wetted perimeter.
- Calculate the cross-sectional area.
- Calculate the hydraulic radius (Step 3 / Step 2)
- Calculate Q, the flow.
- Repeat.
What is a tailwater elevation?
The water surface immediately downstream of the culvert is known as the Tailwater, often synonymous with the water surface of the outlet pool. The tailwater elevation is controlled by a geomorphic feature downstream of the outlet pool. ... The tailwater control elevation also determines the residual pool depth.
