Side channel spillway
SIDE CHANNEL SPILLWAY
- This spillway is suitable for earth or rock fill dams, in narrow canyons and other situations.
- This spillway is also the best choice where a long overflow crest is require so as to limit the surcharge head and also under the situation where abutments are steep and precipitous.
- In this spillway the control weir is kept along the side.
- The flow after passing over the crest turns at approximately 90°.
- Flow may enter the side channel from one side only or from both the sides and one end also.
- Discharge characteristics are similar to ordinary overflow weir, except that at high discharge its crest may be partly submerged.
- Generally a trough is formed on D/S side of the crest and water enters it before taking a turn to flow in the side channel.