1. A diversion headwork is a weir or barrage constructed across a river to divert water into a canal. It regulates water flow into the canal through a head regulator.
2. A barrage differs from a weir in that it uses large gates that can be opened and closed to directly control water levels, whereas a weir uses fixed crest heights.
3. The main purpose of a barrage is to stabilize river water levels for uses like irrigation while still allowing easy control over flow, unlike a dam which relies on water levels behind the full wall height.
1. Diversion headworks divert river water into canals to supply irrigation water. They include weirs or barrages to raise water levels, under sluices to remove silt, and canal head regulators to control water flow into canals.
2. Key components are weirs/barrages, under sluices, divide walls, fish ladders, and canal head regulators. Weirs/barrages raise water levels while under sluices and silt excluders/ejectors remove silt from the water. Canal head regulators control water entering the canals.
3. Site selection considers factors like river characteristics, canal economics, construction feasibility, land and material costs,
Topics:
1. Types of Diversion Head Works
2. Weirs and Barrages
3. Layout Diversion Head Works
4. Causes of Failures of Weirs and Barrages on Permeable Foundations
5. Silt Ejectors and Silt Excluders
The document provides information on diversion headworks for water resources engineering projects. It discusses the different types of diversion headworks including storage and temporary diversion structures. Key components of diversion headworks are described such as weirs, barrages, divide walls, fish ladders, and canal head regulators. Factors for selecting sites for diversion structures are outlined. Causes of failures for weirs built on permeable foundations and remedies are summarized.
Types- selection of the suitable site for the diversion headwork components
of diversion headwork- Causes of failure of structure on pervious foundation- Khosla’s theory- Design of concrete sloping
glacis weir.
Diversion headworks are structures constructed at the head of a canal to divert river water into the canal. They include weirs or barrages that raise the water level, as well as other components like canal head regulators, divide walls, fish ladders, and scouring sluices. The objectives of diversion headworks are to raise water levels, form water storage, control silt entry, and regulate water levels during different seasons. Key considerations for siting diversion headworks include river characteristics, elevation, foundation stability, and access for construction materials.
This document provides an overview of diversion headworks for supplying water to irrigation canals. It discusses the key components of diversion headworks including weirs/barrages, undersluices, divide walls, fish ladders, canal head regulators, and river training works. It also examines site selection factors and design considerations to prevent failures from subsurface piping or uplift and surface scouring. Khosla's theory improved earlier theories by accounting for complex seepage patterns below hydraulic structures.
1. Diversion headworks divert river water into canals to supply irrigation water. They include weirs or barrages to raise water levels, under sluices to remove silt, and canal head regulators to control water flow into canals.
2. Key components are weirs/barrages, under sluices, divide walls, fish ladders, and canal head regulators. Weirs/barrages raise water levels while under sluices and silt excluders/ejectors remove silt from the water. Canal head regulators control water entering the canals.
3. Site selection considers factors like river characteristics, canal economics, construction feasibility, land and material costs,
Topics:
1. Types of Diversion Head Works
2. Weirs and Barrages
3. Layout Diversion Head Works
4. Causes of Failures of Weirs and Barrages on Permeable Foundations
5. Silt Ejectors and Silt Excluders
The document provides information on diversion headworks for water resources engineering projects. It discusses the different types of diversion headworks including storage and temporary diversion structures. Key components of diversion headworks are described such as weirs, barrages, divide walls, fish ladders, and canal head regulators. Factors for selecting sites for diversion structures are outlined. Causes of failures for weirs built on permeable foundations and remedies are summarized.
Types- selection of the suitable site for the diversion headwork components
of diversion headwork- Causes of failure of structure on pervious foundation- Khosla’s theory- Design of concrete sloping
glacis weir.
Diversion headworks are structures constructed at the head of a canal to divert river water into the canal. They include weirs or barrages that raise the water level, as well as other components like canal head regulators, divide walls, fish ladders, and scouring sluices. The objectives of diversion headworks are to raise water levels, form water storage, control silt entry, and regulate water levels during different seasons. Key considerations for siting diversion headworks include river characteristics, elevation, foundation stability, and access for construction materials.
This document provides an overview of diversion headworks for supplying water to irrigation canals. It discusses the key components of diversion headworks including weirs/barrages, undersluices, divide walls, fish ladders, canal head regulators, and river training works. It also examines site selection factors and design considerations to prevent failures from subsurface piping or uplift and surface scouring. Khosla's theory improved earlier theories by accounting for complex seepage patterns below hydraulic structures.
Diversion headworks are structures constructed across rivers to raise water levels and divert water into canals. They have several purposes, including increasing the commanded area, regulating water supply to canals, and controlling silt entry. There are two types - temporary and permanent. Key components include weirs/barrages, under sluices, divide walls, fish ladders, and head regulators. The optimal location depends on the river's characteristics, balancing factors like water availability, construction costs, and proximity to agricultural land.
Diversion headworks, also known as canal headworks, are structures built across rivers to raise the water level and divert water into canals. They serve several purposes, including increasing the area that can be irrigated, regulating water supply to canals, controlling silt entry, and reducing water level fluctuations. There are two types - temporary structures built after floods, and permanent concrete or masonry structures like weirs and barrages. The location depends on the river's characteristics, with the trough or alluvial stage generally preferred. Key components include the weir/barrage, under sluices, divide wall, and head regulators.
A water distribution system is a part of water supply network with components that carry potable water from a centralized treatment plant or wells to consumers to satisfy residential.
Canal headworks are hydraulic structures constructed across rivers to divert water into canals. They raise the river water level and regulate flows. There are two main types - diversion and storage headworks. Diversion headworks like weirs and barrages divert water without storage, while dams form storage reservoirs. Key components include weirs/barrages, divide walls, fish ladders, under sluices, silt excluders, and head regulators. Location depends on river characteristics, and sites must be accessible with suitable foundations. Failure can occur through subsurface piping/uplift or surface scouring during floods. Precautions include reducing exit gradients, providing sheet piles, ensuring floor thickness, using filters and energy
This document provides information about hydraulic structures and diversion head works. It discusses that a hydraulic structure disrupts natural water flow and examples include dams and weirs. It then describes the key components of diversion head works, including weirs, barrages, under-sluices, divide walls, river training works, fish ladders, and canal head regulators. The purpose and functions of each component are explained. Design considerations for weirs and barrages such as their cost, control of flow, and ability to incorporate transportation are compared.
Diversion head works divert river water into canals and include components like weirs, barrages, undersluices, divide walls, fish ladders, head regulators, and silt prevention devices. Weirs and barrages raise the river's water level to divert it into canals. Undersluices and divide walls help control silt and water flow. Fish ladders allow fish to pass through. Head regulators control water entering canals while silt prevention devices like silt excluders and ejectors remove silt from the water and canal bed. Guide banks and marginal embankments also help direct water flow and prevent flooding.
chapter-3.pptx: CHANNEL HEADWORKS AND CANALSmulugeta48
Purposes:
Raises water level in the river
Regulates supply of water into the canal
Controls the entry of silt into the canal
Provides some storage for a short period
Reduces the fluctuations in the level of supply in river
Temporary diversion head works
Consists of a bund constructed across river to raise the water level in the river and will be damaged by floods.
2. Permanent diversion head works
Consists of a permanent structure such as a weir or barrage constructed across river to raise water level in the river.River section at the site should be narrow and well-defined.
Should have a large commanded area.
Site should be such that the weir (or barrage) can be aligned at right angles to the direction of flow in the river.
Good foundation should be available at the site.
Site should be easily accessible by road or rail.
Overall cost of the project should be a minimum
This document discusses different types of water resources including surface water and groundwater. It provides details on reservoirs, including definitions, classifications, and factors to consider when selecting sites. Reservoirs can be used for storage, flood control, or multiple purposes. The document also describes components of water diversion structures like barrages and weirs, as well as methods for extracting groundwater like dug wells, tube wells, and bore wells.
This document provides an overview of hydraulic structures and their components. It defines a hydraulic structure as anything partially or fully submerged in water that disrupts natural flow. Weirs raise water levels while barrages can adjust levels using gates. Dams form deep reservoirs. Diversion structures include temporary barriers and permanent weirs/barrages. Key components are the weir/barrage, divide wall, fish ladder, approach channel, sluices, silt prevention, head regulator, and river training works like guide banks and spurs. The document describes the purpose and design of each component.
This document discusses diversion head works, which divert river water into canals. It describes the objectives of diversion head works as raising the water level, forming storage, controlling silt entry and water level fluctuations. Key components are then outlined, including weirs, barrages, under-sluices, divide walls, fish ladders, and canal head regulators. Weirs use a raised crest to pond water, while barrages use gates. River training works like guide banks and spurs are also discussed, which help ensure smooth, axial river flow. The document provides details on selecting head works sites and designing various structures.
The document discusses the types, location, and components of diversion head works. There are two types of diversion head works - temporary and permanent. Permanent diversion head works consist of structures like weirs or barrages built across rivers to raise water levels and divert water into canals. Key components include the weir/barrage, undersluices, divide wall, fish ladder, canal head regulator, and river training works. The site selection considers factors such as river characteristics, cost, accessibility, and potential impacts.
The document discusses various aspects of selecting a site for a diversion headworks and its components. It provides criteria for selecting an optimal site, such as the river being straight and narrow, having a higher elevation than the irrigation area, and having stable banks. It also discusses types of weirs, barrages, and other structures used at diversion headworks, such as under sluices, fish ladders, canal head regulators, and silt control works. Key considerations for site selection aim to minimize construction costs and water losses while safely diverting water for irrigation.
The document describes the components and purposes of weirs and barrages. Weirs and barrages are solid structures built across rivers to raise water levels and divert water into canals. The main differences are that barrages use gates to regulate flow, while weirs use crest height. Barrages are more expensive than weirs. The structures are used to control water levels and flows, prevent flooding, divert water, and train rivers to reduce impacts on canal headworks. Key components include the main body, divide wall, under sluices, fish ladder, sheet piles, apron, and river training works.
This document discusses various hydraulic structures used for river engineering, including headworks, diversion structures, weirs, and flow control structures. It describes the functions and types of structures such as storage versus diversion headworks, vertical drop versus sloping weirs, and bendway weirs versus engineered log jams. Modes of failure for weirs and methods to control flow and grade using structures like vanes, drop structures, and logjams are also summarized.
The document discusses the components and objectives of diversion headworks. The key components include weirs or barrages, canal head regulators, divide walls, fish ladders, scouring sluices, silt excluders, and guide banks. The objectives are to raise water levels, control silt entry and deposition, and regulate water flow levels throughout the year. Site selection considerations and causes of failure on permeable foundations are also summarized.
Diversion headworks are structures constructed across rivers to raise water levels and divert water into canals. They have several purposes, including increasing the commanded area, regulating water supply to canals, and controlling silt entry. There are two types - temporary and permanent. Key components include weirs/barrages, under sluices, divide walls, fish ladders, and head regulators. The optimal location depends on the river's characteristics, balancing factors like water availability, construction costs, and proximity to agricultural land.
Diversion headworks, also known as canal headworks, are structures built across rivers to raise the water level and divert water into canals. They serve several purposes, including increasing the area that can be irrigated, regulating water supply to canals, controlling silt entry, and reducing water level fluctuations. There are two types - temporary structures built after floods, and permanent concrete or masonry structures like weirs and barrages. The location depends on the river's characteristics, with the trough or alluvial stage generally preferred. Key components include the weir/barrage, under sluices, divide wall, and head regulators.
A water distribution system is a part of water supply network with components that carry potable water from a centralized treatment plant or wells to consumers to satisfy residential.
Canal headworks are hydraulic structures constructed across rivers to divert water into canals. They raise the river water level and regulate flows. There are two main types - diversion and storage headworks. Diversion headworks like weirs and barrages divert water without storage, while dams form storage reservoirs. Key components include weirs/barrages, divide walls, fish ladders, under sluices, silt excluders, and head regulators. Location depends on river characteristics, and sites must be accessible with suitable foundations. Failure can occur through subsurface piping/uplift or surface scouring during floods. Precautions include reducing exit gradients, providing sheet piles, ensuring floor thickness, using filters and energy
This document provides information about hydraulic structures and diversion head works. It discusses that a hydraulic structure disrupts natural water flow and examples include dams and weirs. It then describes the key components of diversion head works, including weirs, barrages, under-sluices, divide walls, river training works, fish ladders, and canal head regulators. The purpose and functions of each component are explained. Design considerations for weirs and barrages such as their cost, control of flow, and ability to incorporate transportation are compared.
Diversion head works divert river water into canals and include components like weirs, barrages, undersluices, divide walls, fish ladders, head regulators, and silt prevention devices. Weirs and barrages raise the river's water level to divert it into canals. Undersluices and divide walls help control silt and water flow. Fish ladders allow fish to pass through. Head regulators control water entering canals while silt prevention devices like silt excluders and ejectors remove silt from the water and canal bed. Guide banks and marginal embankments also help direct water flow and prevent flooding.
chapter-3.pptx: CHANNEL HEADWORKS AND CANALSmulugeta48
Purposes:
Raises water level in the river
Regulates supply of water into the canal
Controls the entry of silt into the canal
Provides some storage for a short period
Reduces the fluctuations in the level of supply in river
Temporary diversion head works
Consists of a bund constructed across river to raise the water level in the river and will be damaged by floods.
2. Permanent diversion head works
Consists of a permanent structure such as a weir or barrage constructed across river to raise water level in the river.River section at the site should be narrow and well-defined.
Should have a large commanded area.
Site should be such that the weir (or barrage) can be aligned at right angles to the direction of flow in the river.
Good foundation should be available at the site.
Site should be easily accessible by road or rail.
Overall cost of the project should be a minimum
This document discusses different types of water resources including surface water and groundwater. It provides details on reservoirs, including definitions, classifications, and factors to consider when selecting sites. Reservoirs can be used for storage, flood control, or multiple purposes. The document also describes components of water diversion structures like barrages and weirs, as well as methods for extracting groundwater like dug wells, tube wells, and bore wells.
This document provides an overview of hydraulic structures and their components. It defines a hydraulic structure as anything partially or fully submerged in water that disrupts natural flow. Weirs raise water levels while barrages can adjust levels using gates. Dams form deep reservoirs. Diversion structures include temporary barriers and permanent weirs/barrages. Key components are the weir/barrage, divide wall, fish ladder, approach channel, sluices, silt prevention, head regulator, and river training works like guide banks and spurs. The document describes the purpose and design of each component.
This document discusses diversion head works, which divert river water into canals. It describes the objectives of diversion head works as raising the water level, forming storage, controlling silt entry and water level fluctuations. Key components are then outlined, including weirs, barrages, under-sluices, divide walls, fish ladders, and canal head regulators. Weirs use a raised crest to pond water, while barrages use gates. River training works like guide banks and spurs are also discussed, which help ensure smooth, axial river flow. The document provides details on selecting head works sites and designing various structures.
The document discusses the types, location, and components of diversion head works. There are two types of diversion head works - temporary and permanent. Permanent diversion head works consist of structures like weirs or barrages built across rivers to raise water levels and divert water into canals. Key components include the weir/barrage, undersluices, divide wall, fish ladder, canal head regulator, and river training works. The site selection considers factors such as river characteristics, cost, accessibility, and potential impacts.
The document discusses various aspects of selecting a site for a diversion headworks and its components. It provides criteria for selecting an optimal site, such as the river being straight and narrow, having a higher elevation than the irrigation area, and having stable banks. It also discusses types of weirs, barrages, and other structures used at diversion headworks, such as under sluices, fish ladders, canal head regulators, and silt control works. Key considerations for site selection aim to minimize construction costs and water losses while safely diverting water for irrigation.
The document describes the components and purposes of weirs and barrages. Weirs and barrages are solid structures built across rivers to raise water levels and divert water into canals. The main differences are that barrages use gates to regulate flow, while weirs use crest height. Barrages are more expensive than weirs. The structures are used to control water levels and flows, prevent flooding, divert water, and train rivers to reduce impacts on canal headworks. Key components include the main body, divide wall, under sluices, fish ladder, sheet piles, apron, and river training works.
This document discusses various hydraulic structures used for river engineering, including headworks, diversion structures, weirs, and flow control structures. It describes the functions and types of structures such as storage versus diversion headworks, vertical drop versus sloping weirs, and bendway weirs versus engineered log jams. Modes of failure for weirs and methods to control flow and grade using structures like vanes, drop structures, and logjams are also summarized.
The document discusses the components and objectives of diversion headworks. The key components include weirs or barrages, canal head regulators, divide walls, fish ladders, scouring sluices, silt excluders, and guide banks. The objectives are to raise water levels, control silt entry and deposition, and regulate water flow levels throughout the year. Site selection considerations and causes of failure on permeable foundations are also summarized.
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Presenation on Diversion Headworks irrigation.pptx
1. Any hydraulic structure which supplies water to the off-taking
canal is called a headwork.
Headwork may be divided into two
1. Storage headwork. 2. Diversion headwork.
1. Storage head works--- Dam is constructed across a river
valley to form storage reservoir, known as storage head works.
Water is supplied to the canal from this reservoir through canal
regulator.
These serves for multipurpose function like hydro- electric
power generation, flood control, fishery.
2. Diversion head works---Weir or barrage is constructed across
a perennial river to raise water level and to divert the water to
canal, is known as diversion head work.
Flow of water in the canal is controlled by canal head
regulator.
Headwork
2. Raises the water level in the river so that the commanded area
is increased.
Regulates the supply of water into the canal.
Controls the entry of silt into the canal.
Provide some storage of water for a short period.
Controls the vagaries of river.
Functions of Diversion Head works
3.
4.
5. Weir or Barrage.
Divide wall or divide groyne.
Fish ladder.
Under-sluices or scouring sluices.
Silt excluder.
Canal head regulator.
River training works such as Marginal bunds and
Guide bunds.
components of diversion head works
6. A weir or low head dam is a barrier or the crest wall of concrete
or masonry across the width of a river that alters the flow
characteristics of water and usually results in a change in the
height of the river level.
Used to control the flow of water for outlets of lakes, ponds,
and reservoirs.
Weir alignment should be at right angles to the direction of
flow.
Weir
7. A barrage is a type of low-head, diversion dam, consists of a
number of large gates that can be opened or closed to
control the amount of water passing through.
This allows the structure to regulate and stabilize river water
elevation upstream for use in irrigation and other systems.
Barrage provides a better control over river flow by a suitable
manipulation of gates.
Current trend is to construct a barrage.
Barrage
8. Barrage Weir
Low set crest High set crest
Ponding by gates Ponding against raised crest
Gated over entire length Shutters in part length
Perfect control on river flow No control
Gates of greater height Shutters of small height, 2m
High floods can be passed with
min afflux
Excessive afflux in high floods
Less silting U/S due to set crest Raised crest causes silting U/S
Longer construction period Shorter construction period
Costly structure Cheaper structure
Silt removal through under-
sluices
No means of silt disposal
Difference between barrage & weir
9. Narrow and well-defined river section.
River should have high, in erodible and non-submersible banks
so that the cost of river training works is minimum.
Good foundation.
Easily accessible by road or rail.
Minimum project Cost.
Construction material should be available near the site.
Suitable arrangement for diversion of river during construction.
DHW should not submerge costly land & property on its U/S.
Suitable locations for components of DHW .
Canals taking-off from DHW should be economical with large
CA.
Length of weir should be minimum.
Site selection for diversion head work
10. High initial low
Disadvantages---
Large afflux during floods causes large submergence.
Crest is high , there is great silting problem.
Raising & lowering of shuttering on the crest is not
convenient, requires more time & labour.
Advantages of weir
11. Good control on the river during floods. The outflow can be
easily regulated by gates.
The afflux during floods is small , submerged area is less.
Good control over silt entry into the canal.
Good control over flow conditions, shoal formations & cross
currents on the U/S of the barrage.
Better facilities for inspection & repair of various structures.
A roadway can be conveniently provided over the structure at
a little additional cost.
Disadvantages---
Initial cost is quite high.
Advantages of barrage
15. To form a still water pocket in front of the canal head so that
the suspended silt can be settled down which then later be
cleaned through the scouring sluices from time to time.
It controls the eddy current or cross current in front of the
canal head
Divide wall
17. It provides a straight approach in front of the canal head.
It resists the overturning effect on the weir or barrage caused
by the pressure of the impounding water.
The fish ladder is provided just by the side of the divide wall
for the free movement of fishes.
Fish ladder
18.
19.
20. i) Preserve a clear and defined river channel
approaching the regulator.
ii) Control the silt entry into the canal.
iii) Pass the low floods without dropping the shutter
of the main weir.
iv) Provide greater water-way for floods, thus
lowering the flood level
Sluice gates
21.
22. are a type of silt control device which functions to exclude
silt from water to entering the canal.
These devices are particularly provided on the river bed in
front of the head regulator.
A silt excluder usually consists of a number of rectangular
tunnels resting on the floor of the undersluice pocket
Silt excluders
23. is a structure constructed in the bed of a river, u/s of a head
regulator to attack the river bed water and divert the same
into the d/s of the river.
Its main function is to prevent the entry of silt into the canal
Silt excluder
24. Silt ejectors, also called silt extractors, are those devices which
extract the silt from the canal water after the silted water has
travelled a certain distance in the off-take canal.
These works are, therefore, constructed on the bed of the
canal, and little distance downstream from the head regulator.
Silt Ejectors
25.
26. Silt ejector is the hydraulic structure located in the canal
headreach such that sediment can be preiodically flushed back
into the river.
It remove the water from the bottom layers of the canal
through tunnels spanning the whole width of the canal and
discharges it into some nearby drain or back to river.
Silt ejector
27. The total length of the river may be divided into following four stages:
1. Mountainous Stage:
The first length of the river originating from hills is known as mountainous
stage of the river.
The longitudinal slope in this stage is very steep and velocity of flow of
water, very fast.
The width of the river in this region is generally very small.
This region is found most suitable for the construction of storage works
like high dams.
Large storages are possible as very deep valleys are easily available here.
Moreover the length of the dam is also relatively small. Materials of
construction are locally available.
This stage is however not suitable for diversion works.
Location of Diversion Head Works:
28. The bed and banks of the river in this stage are made of gravel.
The velocity of flow is considerable though smaller than first
stage.
The river water contains lot of silt load. The river generally
does not flow in a single channel, but is form of small several
channels.
Longitudinal slope is less than first stage but still considerable.
Diversion works can be located in this region of the river.
2. Sub-Mountainous Stage:
29. This length of the river is in plains.
The section of the river is made of alluvial soils or silt.
The longitudinal slope of the river is small and velocity of flow
moderate.
This length of the river is the largest of all other lengths.
Diversion works are mostly located in this length.
The area to be irrigated lies very near to this length and thus
reduces the overall length of the canal network.
3. Alluvial or Trough Stage.
30. This is the last length of the river before it falls into the sea.
This length of river is only a few kilometres long. Here velocity of
flow is very small and silting rate very high. Because of high rate of
silting, the rivers frequently change their course.
No diversion work is constructed in this region. Secondly available
command area near this region is also small.
Canals cannot be taken from mountainous stage, as lot of cuttings
and fillings are involved and thus canal construction becomes very
costly.
Lot of falls will have to be constructed adding still more to the cost.
4. Delta Stage:
31. (i) All the construction materials should be available in the vicinity.
(ii) In order to keep the length of the canal minimum, diversion head works should be
located as near the area to be irrigated as possible.
(iii) The elevation of the water in the river should be such that water may flow to the
area under gravity. If level of water is low, the position of the head works should be
shifted a few kilometres upstream so that increased elevation of water is available.
(iv) The canal should run in such a way that canal is partly in cutting and partly in
filling.
(v) The river at site of diversion, should be neither too wide nor too narrow. The river
should neither be scouring nor silting.
(vi) The river should be straight and flowing in one channel. Its bed and banks should
be stable.
(vii) The canal alignment should be such that minimum streams cross it. This will
reduce the number of cross-drainage works to be constructed.
(viii) The canal should take off, either at 90° or greater than 90° with the river. Canal
should not run parallel to the river. In such circumstances the canal may be eroded
during floods.
32. Weir or barrage is constructed across a perennial river to raise
water level and to divert the water to canal, is known as
diversion head work.
Flow of water in the canal is controlled by canal head
regulator.
It regulates the supply of water into canals
Diversion head works
33. Earthen embankments which are provided to confine the
flood water from the river within an allowable cross-section
and in between the embankments.
Thus the spreading of flood water beyond these marginal
bunds is prevented
Marginal bunds or levees
34. serves the following purposes:
It protects the barrage from the effect of scouring and
erosion.
It provides a straight approach towards the barrage.
It controls the tendency of changing the course of the river.
It controls the velocity of flow near the structure.
Guide bank
35. A barrage is a type of dam; however, instead of being a massive concrete
wall that the water can’t flow over, the barrage is full of gates.
These gates are opened and closed to directly control the amount of water
that passes through it. Having a barrage instead of a dam means that the
flow of water can be kept stable for its intended purpose, such as irrigation
to nearby cities, towns, or farmlands. Unlike a dam, the water stored behind
a barrage depends on the height of its gates and not the height of the entire
wall. The flow and level of water are easily monitored because the gates can
be easily manipulated.
A barrage is constructed when water doesn’t need to be stored but rather
diverted. For this reason, the barrage is usually built across a flat and
relatively slow-moving river. Unlike a dam, which will raise waters nearly to
its height, a barrage will only raise the water level by a few feet. This is also
useful for navigation, because a barrage can increase the depth of a river by
a few feet.
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