The document discusses diversion headworks, which divert water from a river into a canal. There are two types: storage headworks, which comprise a dam to store excess river water for later release; and diversion headworks, which directly divert water into the canal. Diversion headworks have several components, including a weir or barrage across the river to raise the water level, canal head regulators, and sluices. A weir is a solid obstruction across the river, while a barrage is a low weir with adjustable gates to control the water level.

1. 05. Diversion Headworks-1
B.Sc. Civil Engineering 8th Semester
Muhammad Ajmal (PhD)
Lecturer
Agri. Engg. Deptt.
CE-402 Irrigation Engineering

2. Diversion Headworks
❖Any hydraulic structure which supplies mostly silt free water with certain
minimum head into the off-taking canal is called a headwork.

3. Diversion Headworks
 Headworks may be divided into two major classes:
1) Storage Headwork: It comprises the construction of a dam across the river. It
stores water during the period of excess supplies in the river and releases it
when demand exceeds available supply.
2) Diversion Headwork: It serves to divert the required supply into the canal
from the river. The objectives of this type of headworks are as following.
✓ It raises the water level in the river so that the commanded area can be
increased.
✓ It regulates the intake of water into the canal.
✓ It controls the silt entry into the canal.
✓ It reduces fluctuations in the level of supply in the river.

4. Diversion Headworks

5. Diversion Headworks

6. Components of Diversion Headworks
 The components of diversion headworks are:
❖ Weir or barrage
❖ Canal head regulator
❖ Divide Wall
❖ Fish Ladder
❖ Scouring Sluices Under sluices
❖ Silt excluder
❖ Silt ejector.
❖ Marginal embankment or dikes
❖ Guide bank
❖ Silt pocket or trap.

7. Components of Diversion Headworks

8. Weir or Barrage
 Weir is a solid obstruction placed across the
river. Its main function is to raise the water
level so that water can be diverted from canal
to crop field due to head difference.
 Barrage is practically a low weir with an
adjustable gate over this low weir. Heading
up of water is affected by gate.

9. Weir

10. Weir

11. Barrage

12. Barrage

13. Site Selection for Headworks
 To be continued in next class