Canal fall is a solid masonry structure that is made on the canal if the natural ground slope is steeper than the designed channel bed slope.
If the difference in slope is little, a single fall can be made, but If it is higher then falls are made at regular intervals.
Table of Contents
Types of Canal Falls:
- Rapid Canal Fall
- Ogee Canal Fall
- Stepped Falls
- Trapezoidal Notch Falls
- Well Type Fall
- Simple Vertical Drop Falls
- Straight Glacis Fall
- Montague Type Fall
- English Falls or Baffle Fall
1. Rapid Canal Fall:
These falls are long-sloping glacis. The construction cost of rapid canal fall is very high. These types of falls can be constructed if the plan surface is long.
To keep up the slope of the bed curtain walls are provided both upstream and downstream.
2. Ogee Canal Fall
It is consists of concave and convex curves. The slop is varying gradually. The gradual slope helps the smooth transition of flow.
3. Stepped Falls
As the name suggests, it is consists of various steps. These steps are constructed at specific intervals. This type of fall is appropriate for the canal which has it upstream at a very high level as compared to downstream.
4. Trapezoidal Notch falls
In this type of canal fall, a high crested wall is constructed across the channel and then a trapezoidal notch is provided. These types of falls are suitable for low discharge. Trapezoidal nothc fall also very economical.
5. Well Type Fall
Well-type fall consists of an inlet wall with the pipe at its bottom is constructed upstream. This type of fall is also known as drop fall.
An inlet well with the pipe at its bottom is provided upstream. The pipe carries the water to the downstream well or reservoir. If the discharge capacity is more than 0.29 cumecs, downstream well is favored in any case supply is reasonable.
6. Simple Vertical Drop Falls
This type of fall consists of a single vertical drop which permits the upstream water to fall with sudden impact downstream. The downstream works like a cushion for upstream water but dissipates excess steam.
7. Straight Glacis Fall
This is a very popular canal fall in which a raised crest is made across the canal and a gentle straight inclined surface is provided from raised crest to the downstream.
The water coming from upstream crosses the raised peak and falls on the slanted surface with adequate energy dissemination.
8. Montague Type Fall
It is very much like straight glacis fall. In Montague’s fall, glacis isn’t straight. It is built in an illustrative shape to present the vertical segment of speed which improves the energy dissemination to more extent.
9. English Falls or Baffle Fall
For this situation, straight glacis fall is reached out as baffle stage with baffle divider. This is appropriate for any release. The baffle divider is built close to the toe of the straight glacis at the required distance in planned stature. The primary reason for the baffle divider is to make the water-powered bounce from straight glacis to bewilder stage.
