Canal falls are structures constructed across canals to lower the bed level to maintain the designed slope when there is a change in ground level. The main types of canal falls are ogee falls, stepped falls, vertical falls, rapid falls, and straight glacis falls. Canal escapes are side channels that remove surplus water from canals into natural drains. The main types are surplus escapes, tail escapes, and scouring escapes. Cross drainage works include structures like aqueducts and siphon aqueducts to allow canals to pass over drainages when their bed levels differ.
Canal fall- necessity and location- types of falls- Cross regulator and
distributory head regulator- their functions, Silt control devices, Canal
escapes- types of escapes.
Cross drainage works are structures constructed where canals cross natural drainages like rivers or streams. There are several types of cross drainage works depending on the relative bed levels of the canal and drainage. The document discusses determining the maximum flood discharge of a drainage using various empirical formulas and methods. It also covers topics like fluming of canals, which involves contracting the canal width to reduce the size of cross drainage structures.
This document discusses different types of canal outlets used to release water from distributing channels into watercourses. It describes non-modular, semi-modular, and modular outlets. Non-modular outlets discharge based on water level differences, while modular outlets discharge independently of water levels. Semi-modular outlets discharge depending on the channel water level but not the watercourse level. Specific outlet types are also defined, such as pipe outlets, open sluice, and Gibbs, Khanna, and Foote rigid modules. Discharge equations for different outlet types are provided.
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.
Cross section of the canal, balancing depth and canal fslAditya Mistry
1) The document discusses the cross section of irrigation canals, including configurations for cutting, filling, and partial cutting/filling. It describes the main components of a canal cross section such as side slopes, berms, and banks.
2) Balancing depth is defined as the depth of cutting where the quantity of excavated earth equals the amount required to form the canal banks, resulting in the most economical cross section.
3) Canal FSL (Full Supply Level) refers to the normal maximum operating water level of a canal when not affected by floods, corresponding to 100% capacity.
Stream Gauging: Necessity; Selection of gauging sites; Methods of discharge measurement; Area-Velocity method; Venturi flume; Chemical method; weir method; Measurement of velocity; Floats Surface float, Sub–surface float or Double float, Twin float, Velocity rod or Rod float; Pitot tube; Current meter; Working of current meter; rating of current meter; Measurement of area of flow; Measurement of width - Pivot point method; Measurement of depth Sounding rod, Echo- sounder.
This document discusses different types of canal falls, which are structures constructed to lower the bed level of a canal. It describes seven common types of falls: ogee fall, rapid fall, trapezoidal fall, stepped fall, montague fall, vertical drop fall, and straight glacis fall. Each type is suitable for different conditions depending on factors like the height of fall, discharge, site topography, and cost. The document provides details on the design and suitability of each type of canal fall.
The document discusses causes of failure for weirs and barrages built on permeable foundations, including piping/undermining, uplift pressure, hydraulic jump, and scouring. It explains that piping occurs when water percolates through the foundation and erodes soil particles, creating a hollow channel. Uplift pressure from percolating water can also cause failure if the structure's weight cannot counterbalance it. Hydraulic jump and high-velocity surface flow can produce suction pressures and scour soil. The document recommends increasing the seepage path using sheet piles, increasing floor thickness to resist uplift, and using energy dissipaters and filters to prevent soil loss and structural failure.
Canal fall- necessity and location- types of falls- Cross regulator and
distributory head regulator- their functions, Silt control devices, Canal
escapes- types of escapes.
Cross drainage works are structures constructed where canals cross natural drainages like rivers or streams. There are several types of cross drainage works depending on the relative bed levels of the canal and drainage. The document discusses determining the maximum flood discharge of a drainage using various empirical formulas and methods. It also covers topics like fluming of canals, which involves contracting the canal width to reduce the size of cross drainage structures.
This document discusses different types of canal outlets used to release water from distributing channels into watercourses. It describes non-modular, semi-modular, and modular outlets. Non-modular outlets discharge based on water level differences, while modular outlets discharge independently of water levels. Semi-modular outlets discharge depending on the channel water level but not the watercourse level. Specific outlet types are also defined, such as pipe outlets, open sluice, and Gibbs, Khanna, and Foote rigid modules. Discharge equations for different outlet types are provided.
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.
Cross section of the canal, balancing depth and canal fslAditya Mistry
1) The document discusses the cross section of irrigation canals, including configurations for cutting, filling, and partial cutting/filling. It describes the main components of a canal cross section such as side slopes, berms, and banks.
2) Balancing depth is defined as the depth of cutting where the quantity of excavated earth equals the amount required to form the canal banks, resulting in the most economical cross section.
3) Canal FSL (Full Supply Level) refers to the normal maximum operating water level of a canal when not affected by floods, corresponding to 100% capacity.
Stream Gauging: Necessity; Selection of gauging sites; Methods of discharge measurement; Area-Velocity method; Venturi flume; Chemical method; weir method; Measurement of velocity; Floats Surface float, Sub–surface float or Double float, Twin float, Velocity rod or Rod float; Pitot tube; Current meter; Working of current meter; rating of current meter; Measurement of area of flow; Measurement of width - Pivot point method; Measurement of depth Sounding rod, Echo- sounder.
This document discusses different types of canal falls, which are structures constructed to lower the bed level of a canal. It describes seven common types of falls: ogee fall, rapid fall, trapezoidal fall, stepped fall, montague fall, vertical drop fall, and straight glacis fall. Each type is suitable for different conditions depending on factors like the height of fall, discharge, site topography, and cost. The document provides details on the design and suitability of each type of canal fall.
The document discusses causes of failure for weirs and barrages built on permeable foundations, including piping/undermining, uplift pressure, hydraulic jump, and scouring. It explains that piping occurs when water percolates through the foundation and erodes soil particles, creating a hollow channel. Uplift pressure from percolating water can also cause failure if the structure's weight cannot counterbalance it. Hydraulic jump and high-velocity surface flow can produce suction pressures and scour soil. The document recommends increasing the seepage path using sheet piles, increasing floor thickness to resist uplift, and using energy dissipaters and filters to prevent soil loss and structural failure.
A canal is an artificial channel constructed to carry water from a river or reservoir to fields. Canals are classified based on their source of water supply, financial purpose, function, boundary type, water discharge level, and alignment. Canal alignment should aim to irrigate the maximum area with minimum length and cost. The balancing depth is the depth of cutting where the amount of cut material equals the amount of fill. Canal lining reduces water seepage and includes hard surface materials like concrete and softer materials like compacted earth.
Present slideshow provides brief introductory part of various Intake Structures. This is useful for Environmental Engineering Students, faculties and learners.
Canals are human-made waterways that allow boats and ships to pass between bodies of water. They are also used to transport water for irrigation and other human uses. Canals are classified in several ways, including whether the water source is permanent or temporary, the type of soil boundary, the financial purpose, water discharge volume, and canal alignment. The various types of canals include permanent canals, inundation canals, irrigation canals, power canals, and side-slope canals.
Diversion headworks are structures constructed at the head of a canal to divert river water into the canal. They include components like weirs, barrages, canal head regulators, divide walls, fish ladders, and guide banks. The objectives are to raise water levels, control silt entry, regulate water flow, and allow fish passage. Proper site selection and design are needed to prevent failures from subsurface water flow, uplift pressure, hydraulic jumps, or scouring during floods. Remedies include increasing seepage lengths, adding sheet piles, and using thicker impervious floors.
This presentation is covered topic of cross drainage work. In which topics necessity of Cross drainage structures, their types and selection,
comparative merits and demerits, design of
various types of cross-drainage structure:aqueducts, siphon aqueduct, super passage
siphon, level crossing and other types covered.
This document provides an overview of reservoir planning and surveys. It discusses the different types of reservoirs and surveys conducted in reservoir planning, including reconnaissance, preliminary, and detailed surveys. Key steps in reservoir planning include engineering, hydrological, and geological surveys to identify suitable dam sites and storage capacity. Control levels like top bund level, high flood level, and full tank level are also discussed. Factors affecting silting and methods to control silting are outlined. The document provides details on various stages of reservoir planning and development.
The document provides information on diversion head works and their components. It can be summarized as:
1) Diversion head works are structures constructed at the head of a canal to divert river water into the canal and ensure a regulated supply of silt-free water with a minimum head.
2) Key components of diversion head works include under sluices, divide walls, fish ladders, silt exclusion devices, guide banks, and head regulators. Under sluices control silt entry and water levels. Divide walls separate flows. Fish ladders allow fish passage.
3) Site selection factors for diversion head works include suitable foundations, positioning the weir at a right angle to river flow, space for
Regulation works are structures constructed to regulate water flow in canals. The main types are head regulators, cross regulators, canal escapes, and canal outlets. Head regulators control water entry into off-taking channels from parent channels. Cross regulators are located downstream of off-takes and help control water levels and closures for repairs. Canal outlets connect distribution channels to field channels and supply water to irrigation fields at regulated discharges.
Spillways are structures used to release surplus flood waters from a reservoir in a controlled manner. The main types of spillways include ogee or overflow spillways, chute spillways, morning glory spillways, and siphon spillways. To determine spillway capacity, engineers study past flood data and rainfall records to calculate the maximum probable flood, then add a margin of safety like 25%. This establishes the required discharge capacity. Energy dissipators like stilling basins are also important to safely discharge flood waters downstream.
Hydraulic Design of Sewer:
Hydraulic formulae, maximum and minimum velocities in sewer, hydraulic
characteristics of circular sewer in running full and partial full conditions,
laying and testing of sewer, sewer appurtenances and network.
Khosla modified Bligh's theory for designing irrigation structures on permeable foundations. Khosla accounted for actual flow patterns below impermeable bases, unlike Bligh. Khosla derived equations to calculate uplift pressures and exit gradients at key points for structures with single or multiple piles. He also defined safe exit gradients and developed a method of independent variables to solve complex profiles by breaking them into simple components and applying corrections. Khosla's theory is now used for designing hydraulic structures on permeable foundations.
A weir is a solid structure built across a river to raise the water level and divert water into canals. There are different types of weirs including masonry weirs with vertical drops, rock fill weirs with sloping aprons, and concrete weirs with downstream slopes. Weirs can fail due to subsurface piping, uplift pressure, surface water suction or scouring. Remedies include installing sheet piles and ensuring sufficient floor thickness and length. A barrage is similar to a weir but uses gates rather than a solid structure to control water levels. Barrages are more expensive than weirs but allow better control of water levels and less silting during floods by raising the gates.
This document provides information on reservoirs for water storage. It defines a reservoir as an artificial lake created by a dam to store excess water. Reservoirs can be used for multiple purposes like flood control, irrigation, water supply, power generation, fisheries and navigation. The key aspects discussed include reservoir types (storage, flood control, distribution), site selection factors, necessary investigations like surveys and yield/capacity calculations. Sedimentation in reservoirs over time is also explained, along with various control measures like afforestation, check dams and contour bunds.
The document discusses the planning of reservoirs, outlining several key steps:
1) Decision makers must determine the needs and purposes of the reservoir while considering constraints. This includes social and financial factors.
2) All relevant existing information is assembled, such as previous studies, geological and hydrological data, population and demand forecasts.
3) Potential dam and reservoir sites are identified and evaluated based on topographical suitability, available storage, and other factors. Environmental and social impacts are also assessed.
This document discusses various types of canal regulation works including canal falls, escapes, regulators, and outlets. It describes the necessity and types of canal falls, which are constructed when the natural ground slope is steeper than the designed canal bed slope. The types of falls discussed include ogee falls, stepped falls, vertical falls, rapid falls, straight glacis falls, trapezoidal notch falls, well or cylinder notch falls, Montague type falls, and Inglis or baffle falls. The document also discusses canal escapes, head regulators, cross regulators, silt control devices, and canal outlets/modules. In particular, it explains the functions and construction of head regulators and cross regulators.
Here you will get all information about sewer design, its type & various tests carried out on it for any leakage or any obstruction present and of improper joints.
This document discusses floods and methods for estimating peak flood discharge. It begins by defining a flood and design flood. It then describes various methods for estimating peak flood discharge, including using physical indicators, empirical formulas, unit hydrographs, the rational method, and flood frequency studies. As an example of applying the rational method, it calculates the peak discharge for a culvert project in Alberta, Canada with a 50-year return period. It also provides an example of using Gumbel's extreme value distribution to estimate flood discharges with 100-year and 150-year return periods based on annual maximum flood data from 1951-1977.
This document describes Snyder's synthetic unit hydrograph method. Snyder's method allows computation of key hydrograph characteristics using watershed properties. These include:
1. Lag time, which is related to watershed time of concentration based on length and slope.
2. Hydrograph duration, which is typically 1/5.5 of the lag time.
3. Peak discharge, which is related to watershed area, storage coefficient, and time parameters.
4. Other hydrograph properties like width can also be estimated using the peak discharge and empirical coefficients. The synthetic hydrograph provides an estimate of watershed runoff for both gauged and ungauged locations.
Canal Regulation Works:
Canal Fall- Necessity and Location- Types of Falls- Cross Regulator and Distributory Head Regulator- Their Functions, Silt Control Devices, Canal Escapes- Types of Escapes.
MODULE 4 REGULATING AND CROSS DRAINAGE WORKS.pptxSilasChaudhari
Canal regulation works include structures used to regulate flow in canals such as canal falls, regulators, escapes, outlets, and flumes. Canal falls are used when the natural ground slope is steeper than the canal design slope. They lower the canal bed level in steps to maintain the design slope. Common types of canal falls include ogee falls, stepped falls, and vertical falls. Canal regulators are used to control flow in main canals and distributaries. Cross regulators are located downstream of off-takes to control flow to off-taking canals. Canal escapes remove surplus water from canals. Cross-drainage works are structures built where canals cross natural drainages to allow separate flow of canal and drainage waters
A canal is an artificial channel constructed to carry water from a river or reservoir to fields. Canals are classified based on their source of water supply, financial purpose, function, boundary type, water discharge level, and alignment. Canal alignment should aim to irrigate the maximum area with minimum length and cost. The balancing depth is the depth of cutting where the amount of cut material equals the amount of fill. Canal lining reduces water seepage and includes hard surface materials like concrete and softer materials like compacted earth.
Present slideshow provides brief introductory part of various Intake Structures. This is useful for Environmental Engineering Students, faculties and learners.
Canals are human-made waterways that allow boats and ships to pass between bodies of water. They are also used to transport water for irrigation and other human uses. Canals are classified in several ways, including whether the water source is permanent or temporary, the type of soil boundary, the financial purpose, water discharge volume, and canal alignment. The various types of canals include permanent canals, inundation canals, irrigation canals, power canals, and side-slope canals.
Diversion headworks are structures constructed at the head of a canal to divert river water into the canal. They include components like weirs, barrages, canal head regulators, divide walls, fish ladders, and guide banks. The objectives are to raise water levels, control silt entry, regulate water flow, and allow fish passage. Proper site selection and design are needed to prevent failures from subsurface water flow, uplift pressure, hydraulic jumps, or scouring during floods. Remedies include increasing seepage lengths, adding sheet piles, and using thicker impervious floors.
This presentation is covered topic of cross drainage work. In which topics necessity of Cross drainage structures, their types and selection,
comparative merits and demerits, design of
various types of cross-drainage structure:aqueducts, siphon aqueduct, super passage
siphon, level crossing and other types covered.
This document provides an overview of reservoir planning and surveys. It discusses the different types of reservoirs and surveys conducted in reservoir planning, including reconnaissance, preliminary, and detailed surveys. Key steps in reservoir planning include engineering, hydrological, and geological surveys to identify suitable dam sites and storage capacity. Control levels like top bund level, high flood level, and full tank level are also discussed. Factors affecting silting and methods to control silting are outlined. The document provides details on various stages of reservoir planning and development.
The document provides information on diversion head works and their components. It can be summarized as:
1) Diversion head works are structures constructed at the head of a canal to divert river water into the canal and ensure a regulated supply of silt-free water with a minimum head.
2) Key components of diversion head works include under sluices, divide walls, fish ladders, silt exclusion devices, guide banks, and head regulators. Under sluices control silt entry and water levels. Divide walls separate flows. Fish ladders allow fish passage.
3) Site selection factors for diversion head works include suitable foundations, positioning the weir at a right angle to river flow, space for
Regulation works are structures constructed to regulate water flow in canals. The main types are head regulators, cross regulators, canal escapes, and canal outlets. Head regulators control water entry into off-taking channels from parent channels. Cross regulators are located downstream of off-takes and help control water levels and closures for repairs. Canal outlets connect distribution channels to field channels and supply water to irrigation fields at regulated discharges.
Spillways are structures used to release surplus flood waters from a reservoir in a controlled manner. The main types of spillways include ogee or overflow spillways, chute spillways, morning glory spillways, and siphon spillways. To determine spillway capacity, engineers study past flood data and rainfall records to calculate the maximum probable flood, then add a margin of safety like 25%. This establishes the required discharge capacity. Energy dissipators like stilling basins are also important to safely discharge flood waters downstream.
Hydraulic Design of Sewer:
Hydraulic formulae, maximum and minimum velocities in sewer, hydraulic
characteristics of circular sewer in running full and partial full conditions,
laying and testing of sewer, sewer appurtenances and network.
Khosla modified Bligh's theory for designing irrigation structures on permeable foundations. Khosla accounted for actual flow patterns below impermeable bases, unlike Bligh. Khosla derived equations to calculate uplift pressures and exit gradients at key points for structures with single or multiple piles. He also defined safe exit gradients and developed a method of independent variables to solve complex profiles by breaking them into simple components and applying corrections. Khosla's theory is now used for designing hydraulic structures on permeable foundations.
A weir is a solid structure built across a river to raise the water level and divert water into canals. There are different types of weirs including masonry weirs with vertical drops, rock fill weirs with sloping aprons, and concrete weirs with downstream slopes. Weirs can fail due to subsurface piping, uplift pressure, surface water suction or scouring. Remedies include installing sheet piles and ensuring sufficient floor thickness and length. A barrage is similar to a weir but uses gates rather than a solid structure to control water levels. Barrages are more expensive than weirs but allow better control of water levels and less silting during floods by raising the gates.
This document provides information on reservoirs for water storage. It defines a reservoir as an artificial lake created by a dam to store excess water. Reservoirs can be used for multiple purposes like flood control, irrigation, water supply, power generation, fisheries and navigation. The key aspects discussed include reservoir types (storage, flood control, distribution), site selection factors, necessary investigations like surveys and yield/capacity calculations. Sedimentation in reservoirs over time is also explained, along with various control measures like afforestation, check dams and contour bunds.
The document discusses the planning of reservoirs, outlining several key steps:
1) Decision makers must determine the needs and purposes of the reservoir while considering constraints. This includes social and financial factors.
2) All relevant existing information is assembled, such as previous studies, geological and hydrological data, population and demand forecasts.
3) Potential dam and reservoir sites are identified and evaluated based on topographical suitability, available storage, and other factors. Environmental and social impacts are also assessed.
This document discusses various types of canal regulation works including canal falls, escapes, regulators, and outlets. It describes the necessity and types of canal falls, which are constructed when the natural ground slope is steeper than the designed canal bed slope. The types of falls discussed include ogee falls, stepped falls, vertical falls, rapid falls, straight glacis falls, trapezoidal notch falls, well or cylinder notch falls, Montague type falls, and Inglis or baffle falls. The document also discusses canal escapes, head regulators, cross regulators, silt control devices, and canal outlets/modules. In particular, it explains the functions and construction of head regulators and cross regulators.
Here you will get all information about sewer design, its type & various tests carried out on it for any leakage or any obstruction present and of improper joints.
This document discusses floods and methods for estimating peak flood discharge. It begins by defining a flood and design flood. It then describes various methods for estimating peak flood discharge, including using physical indicators, empirical formulas, unit hydrographs, the rational method, and flood frequency studies. As an example of applying the rational method, it calculates the peak discharge for a culvert project in Alberta, Canada with a 50-year return period. It also provides an example of using Gumbel's extreme value distribution to estimate flood discharges with 100-year and 150-year return periods based on annual maximum flood data from 1951-1977.
This document describes Snyder's synthetic unit hydrograph method. Snyder's method allows computation of key hydrograph characteristics using watershed properties. These include:
1. Lag time, which is related to watershed time of concentration based on length and slope.
2. Hydrograph duration, which is typically 1/5.5 of the lag time.
3. Peak discharge, which is related to watershed area, storage coefficient, and time parameters.
4. Other hydrograph properties like width can also be estimated using the peak discharge and empirical coefficients. The synthetic hydrograph provides an estimate of watershed runoff for both gauged and ungauged locations.
Canal Regulation Works:
Canal Fall- Necessity and Location- Types of Falls- Cross Regulator and Distributory Head Regulator- Their Functions, Silt Control Devices, Canal Escapes- Types of Escapes.
MODULE 4 REGULATING AND CROSS DRAINAGE WORKS.pptxSilasChaudhari
Canal regulation works include structures used to regulate flow in canals such as canal falls, regulators, escapes, outlets, and flumes. Canal falls are used when the natural ground slope is steeper than the canal design slope. They lower the canal bed level in steps to maintain the design slope. Common types of canal falls include ogee falls, stepped falls, and vertical falls. Canal regulators are used to control flow in main canals and distributaries. Cross regulators are located downstream of off-takes to control flow to off-taking canals. Canal escapes remove surplus water from canals. Cross-drainage works are structures built where canals cross natural drainages to allow separate flow of canal and drainage waters
This document provides information on various canal structures, including regulation works like canal falls, head regulators, cross regulators, canal escapes and outlets. It describes the purpose and design of a canal fall, including the different types of falls. It also discusses canal escapes, their purposes as safety valves and types including surplus escapes, tail escapes and scouring escapes. Finally, it summarizes the purpose and typical construction of head regulators and cross regulators.
Canal falls are vertical drops constructed in canals when the natural ground slope is steeper than the designed canal slope. They allow the canal slope to be maintained without excessive filling. Different types of canal falls include ogee falls with gradual convex/concave surfaces, rapid falls with long sloping walls, stepped falls with vertical steps, and vertical falls where water falls into a cistern below. The type of fall used depends on the ground conditions and needed slope adjustment. Falls dissipate energy and protect canal beds and sides from erosion.
hydraulic structures in civil engineeringBittuRajkumar
The document discusses various topics related to irrigation engineering including canal falls, canal escapes, and types of canal falls. It provides details on the purpose and necessity of canal falls when the natural ground slope is steeper than the designed canal slope. It describes different types of canal falls such as ogee falls, rapid falls, stepped falls, and vertical drop falls. The document also covers the purpose, types, and location of canal escapes which are structures used to discharge excess water from canals.
Canal regulation works are structures constructed to regulate water flow in canals. This document discusses various types of canal regulation works including canal falls. Canal falls are constructed across canals to lower the water level and dissipate excess energy when the natural ground slope is steeper than the canal design slope. Different types of falls are discussed such as ogee falls, rapid falls, stepped falls, and others; each has a distinct design to best suit different ground level conditions and dissipate water energy. Proper construction of falls is necessary for efficient and safe operation of irrigation canals.
This presentation covered Diversion head work topic. Details topics selection of the suitable site for the
diversion headwork- different parts of
diversion headwork- Causes of failure of
structure on pervious foundation- Khosla’s
theory- Design of concrete sloping glacis weir covered.
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 at the head of a canal to divert river water into the canal. Their objectives are to raise the water level, form water storage, control silt entry and deposition, and regulate water level fluctuations. Key components include a weir or barrage, canal head regulator, divide wall, fish ladder, scouring sluices, silt excluder, silt ejector, and marginal embankments. Together, these structures divert and regulate river flow into the canal while attempting to minimize silt accumulation and allow fish passage.
spillway,types of spillways,
Design principles of Ogee spillways ,Spillway gates. Energy
Dissipaters and Stilling Basins Significance of Jump Height Curve and Tail Water Rating
Curve,
USBR and Indian types of Stilling Basins.
The document discusses different types of canal regulation structures used to control water flow and levels in canals. It describes canal falls/drops, which regulate water supply levels when there is a change in canal bed elevation. Distributary head regulators control water supply to off-taking channels, while cross regulators control water levels and downstream discharge. Canal escapes dispose of excess water during heavy rains and canal outlets connect watercourses to distributary channels. Specific types of falls discussed include ogee, rapid, stepped, notch, and vertical drop falls. Design considerations for cross regulators and distributary head regulators include crest length, cutoff depths, and equations to calculate design discharge and head over the regulator.
This document provides information on diversion head works for canals. It defines diversion head works as structures constructed at the head of a canal to divert river water into the canal. The objectives are to raise the water level and regulate supply. Common structures include weirs and barrages. Weirs raise water level using a raised crest, while barrages use gates to pond water. Other components are under-sluices, divide walls, river training works, and canal head regulators which control water flow into the canal. Careful site selection considers factors like river characteristics, land use, and material availability.
Spillways, Spillway capacity, flood routing through spillways, different type...Denish Jangid
The document discusses spillways, which are structures used to safely discharge water from reservoirs when the water level rises too high. Spillways typically have several key components, including an approach channel, control structure, discharge carrier, discharge channel, and energy dissipators. The control structure regulates water flow and prevents discharge below a fixed level. Energy dissipators, like bucket or baffle types, reduce the water's velocity and kinetic energy before it reaches downstream areas. Spillways must provide stability, safely pass flood waters, operate efficiently, and do so economically.
This document provides information on canal irrigation systems. It discusses the various components of canal distribution systems including main canals, branch canals, distributaries, minors, and watercourses. It also describes canal structures like regulators, river training works, and different types of canal falls used to change the water level. The key purpose of the document is to outline the design and components of canal irrigation networks for transporting water from its source to agricultural fields.
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.
This presentation discusses different types of spillways used in dam structures. Spillways are needed to safely discharge water from the reservoir during floods to prevent overtopping of the dam. The main types discussed are chute, shaft, saddle, and side channel spillways. Chute spillways convey water down an excavated open channel with a steep slope. Shaft spillways allow water to pass through a vertical shaft and horizontal conduit below the dam. Saddle spillways use natural depressions as spillway routes. Side channel spillways route flood water parallel to the dam.
WEIRS VERSUS BERRAGE
TYPES OF WEIRS
COMPONENT PARTS OF A WEIR
CAUSES OF FAILURE OF WEIRS & THEIR REMEDIES
DESIGN CONSIDERATIONS
DESIGN FOR SURFACE FLOW
DESIGN OF BARRAGE OR WEIR
This document discusses various types of cross-drainage works and canal structures used in irrigation projects. There are three main types of cross-drainage works:
1) When the irrigation canal passes over the drainage (aqueduct, siphon aqueduct)
2) When the drainage passes over the irrigation canal (super passage, siphon super passage)
3) When the drainage and canal intersect at the same level (level crossing, inlet and outlet).
Canal structures discussed include canal falls (ogee fall, rapid fall, stepped fall), regulators, escapes and outlets. Canal falls are used when the canal bed slope needs to change due to terrain, and come in various types depending on the slope and
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The document discusses the importance of premarital screening or testing before marriage. It explains that premarital screening involves testing prospective spouses for infectious diseases, genetic disorders, and compatibility to help ensure a healthy marriage and family. Compatibility is assessed through both traditional Indian kundli matching of astrological charts as well as modern medical testing. While kundli matching provides useful information, medical screening can detect diseases and identify health risks that could impact a couple's well-being and ability to have children. The document recommends couples undergo premarital screening through blood tests, physical exams, and counseling to aid in informed decision making.
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2. Syllabus
• Canal Regulation Works
• Canal Fall- Necessity and Location- Types of
Falls- Cross Regulator and Distributory Head
Regulator- Their Functions, Silt Control
Devices, Canal Escapes- Types of Escapes.
• Cross Drainage Works: Types- selection of
suitable type of CD works- aqueduct and
Siphon aqueduct
3. What is Canal Fall?
• Whenever the available natural ground slope
is steep than the designed bed slope of the
channel, the difference is adjusted by
constructing vertical ‘falls’ or ‘drops’ in the canal
bed at suitable intervals, as shown in figure
below. Such a drop in a natural canal bed will not
be stable and, therefore, in order to retain this
drop, a masonry structure is constructed. Such a
structure is called a Canal Fall or a Canal drop.
5. Canal Fall
Irrigation canals are designed for a prescribed bed slope
so that velocity becomes non silting or non scouring.
But if the ground topography is such that in order to
maintain the canal designed slope, indefinite filling
from falling ground level is to be made. This indefinite
filling is avoided by constructing a hydraulic structure
in the place of sudden bed level. This hydraulic
structure is called canal fall or drop. Beyond the canal
fall, canal again maintains its designed slope.
6. Canal Fall
• Thus, a canal fall or drop is an irrigation structure
constructed across a canal to lower down its bed level
to maintain the designed slope when there is a change
of ground level to maintain the designed slope when
there is change of ground level. This falling water at
the fall has some surplus energy. The fall is
constructed in such a way that it can destroy this
surplus energy.
7. Necessity of Canal Falls
• When the slope of the ground suddenly changes
to steeper slope, the permissible bed slope can
not be maintained. It requires excessive earthwork
in filling to maintain the slope. In such a case falls
are provided to avoid excessive earth work in filling
9. Necessity of Canal Falls
• When the slope of the ground is more or
less uniform and the slope is greater than the
permissible bed slope of canal.
10. Necessity of Canal Falls
• In cross-drainage works, when the difference
between bed level of canal and that of
drainage is small or when the F.S.L of the
canal is above the bed level of drainage
then the canal fall is necessary to carry the
canal water below the stream or drainage.
12. Types of Canal Fall
• Depending on the ground level conditions and shape of
the fall the various types of fall are:
Ogee Fall
• The ogee fall was constructed by Sir Proby Cautley on
the Ganga Canal. This type of fall has gradual convex
and concave surfaces i.e. in the ogee form. The gradual
convex and concave surface is provided with an aim to
provide smooth transition and to reduce disturbance
and impact. A hydraulic jump is formed which
dissipates a part of kinetic energy. Upstream and
downstream of the fall is provided by Stone Pitching.
14. Types of Canal Fall
Stepped Fall
• It consists of a series of vertical drops in the form of
steps. This steps is suitable in places where sloping
ground is very long and require a long glacis to connect
the higher bed level u/s with lower bed level d/s. it is
practically a modification of rapid fall. The sloping
glacis is divided into a number drops to bring down the
canal bed step by step to protect the canal bed and sides
from damage by erosion. Brick walls are provided at
each drop. The bed of the canal within the fall is
protected by rubble masonry with surface finishing by
rich cement mortar.
16. Types of Canal Fall
Vertical Fall (Sarda Fall)
• In the simple type, canal u/s bed is on the level of
upstream curtain wall, canal u/s bed level is
below the crest of curtain wall. In both the
cases, a cistern is formed to act as water cushion.
Floor is made of concrete u/s and d/s side stone
pitching with cement grouting is provided. This
type of fall is used in Sarda Canal UP and
therefore, it is also called Sarda Fall.
18. Types of Canal Fall
Rapid Fall
• When the natural ground level is even and
rapid, this rapid fall is suitable. It consists of
long sloping glacis. Curtain walls are provided
on both u/s and d/s sides. Rubble masonry with
cement grouting is provided from u/s curtain
wall to d/s curtain wall. Masonry surface is
finished with a rich cement mortar.
20. Types of Canal Fall
Straight Glacis Fall
• It consists of a straight glacis provided with a
crest wall. For dissipation of energy of flowing
water, a water cushion is provided. Curtain
walls are provided at toe and heel. Stone
pitching is required at upstream and
downstream of the fall.
22. Types of Canal Fall
Trapezoidal Notch Fall
• It was designed by Reid in 1894. In this type a
body or foundation wall across the channel
consisting of several trapezoidal notches between
side pier and intermediate pier is constructed. The
sill of the notches are kept at upstream bed level
of the canal. The body wall is made of concrete.
An impervious floor is provided to resist the
scouring effect of falling water. Upstream and
downstream side of the fall is protected by stone
pitching finished with cement grouting
24. Types of Canal Fall
Well or Cylinder Notch Fall
• In this type, water of canal from higher level is
thrown in a well or a cylinder from where it
escapes from bottom. Energy is dissipated in
the well in turbulence. They are suitable for
low discharges and are economical also.
25. Types of Canal Fall
Montague Type Fall
• In the straight glacis type profile, energy
dissipation is not complete. Therefore,
montague developed this type of profile where
energy dissipation takes place. His profile is
parabolic and is given by the following
equation,
27. Types of Canal Fall
Inglis or Baffle Fall
• Here glacis is straight and sloping, but baffle
wall provided on the downstream floor
dissipate the energy. Main body of glacis is
made of concrete. Curtain walls both at toe and
heel are provided. Stone pitching are essential
both at u/s and d/s ends
29. Canal Escape
• It is a side channel constructed to remove surplus
water from an irrigation channel (main canal,
branch canal, or distributary etc.) into a natural
drain.
• The water in the irrigation channel may become
surplus due to -
• Mistake
• Difficulty in regulation at the head
• Excessive rainfall in the upper reaches
• Outlets being closed by cultivators as they find
the demand of water is over
30. Canal Escape
• It is the structure required to dispose of surplus or
excess water from canal from time to time. Thus, a
canal escape serves as safety valve for canal system. It
provides protection to the canal from possible damage
due to excess supply which may be due to mistake in
releasing water at head regulator or heavy rainfall that
makes sudden regular demand of water. The excess
supply makes the canal banks vulnerable to failure due
to overtopping or dangerous leaks. Therefore, provision
for disposing this surplus water in form of canal
escapes at suitable intervals along the canal is essential.
Moreover emptying canal for repair and maintenance
and removal of sediment deposited in the canal can also
be achieved with the help of canal escapes.
31. Escapes are usually of the following
three types.
Surplus Escape
• It is also called regulator type. In this type sill
of the escape is kept at canal bed level and the
flow is controlled by a gate. This type of
escapes are preferred now-a-days as they give
better control and can be used for employing
the canal for maintenance.
34. Escapes are usually of the following
three types.
Tail Escape
• A tail escape is provided at the tail end of the
canal and is useful in maintaining the required
FSL in the tail reaches of the canal and
hence, they are called tail escape.
36. Escapes are usually of the following
three types.
Scouring Escape
• This escape is constructed for the purpose of scouring
of excess silt deposited in the head reaches from time to
time. Hence, it is called scouring escape. Here the sill
of the regulator is kept at about 0.3 m below the canal
bed level at escape site. When deposited silt to be
scoured, a higher discharge than the FSL is allowed to
enter the canal from the head works. The gate of the
escape is raised so as to produce scouring velocity
which remove the deposited silt. This type of Escape
has become obsolete as silt ejector provided in the
canal can produce better efficiency.
38. Head Regulator
• Regulators Constructed at the off taking point are called head
regulators. When it is constructed at the head of main canal it
is known as canal head regulator. And when it is constructed at
the head of distributary, it is called distributary head regulator.
• Function:
• To control the entry of water either from the reservoir or from
the main canal.
• To control the entry of silt into off taking or main canal.
• To serve as a meter for measuring discharge of water.
39. Head Regulator
• Construction: The components of head regulator
depends upon the size of canal and location of head
regulator. It consists of one or more gated research
openings with barrels running through the bank. For
large canals head regulators are flumed to facilitate
the measurement of discharge.
41. Cross Regulator
• Cross Regulator
• A Regulator Constructed in the main canal or parent
canal downstream of an off take canal is called cross-
regulator.
• It is generally constructed at a distance of 9 to 12 km
along the main canal and 6 to 10 km along branch
canal.
• Functions:
• (i) To Control the flow of water in canal system
• (ii) To feed the off taking Canals
• (iii) To enable closing of the canal breaches on the d/s
• (iv) To provide roadway for vehicular traffic
43. Cross Regulator
Construction: For Cross Regulators abutments
with grooves and piers are constructed parallel to
the parent canal. The sill of regulation is kept
little higher than the u/s bed level of canal across
which it is constructed. Vertical lift gates are
fitted in the grooves. The gates can be operate
from the road.
48. Silt Control Devices
• Scouring Sluices or Under sluices, silt pocket and silt
excluders
• The above three components are employed for silt
control at the head work. Divide wall creates a silt
pocket. Silt excluder consists of a number under tunnels
resting on the floor pocket. Top floor of the tunnel is at
the level of sill of the head regulator.
• Various tunnels of different lengths are made. The
tunnel near the head regulator is of same length of head
regulator and successive tunnels towards the divide
wall are short. Velocity near the silt laden water is
disposed downstream through tunnels and under
sluices.
49. Silt Control Devices
• Silt Excluder: The silt excluder is located on
the u/s of diversion weir and in front of the
head regulator. The object is to remove silt that
has entered in the stilling basin through
scouring sluices.
• Silt Ejector: Silt Ejector is located in the canal
take off from the diversion weir at 6 to 10 km
in the canal reach. It ejects the silt that has
entered in the canal
53. Canal Outlet/modules
• A canal outlet or a module is a small
structure built at the head of the water
course so as to connect it with a minor or a
distributary channel.
• It acts as a connecting link between the
system manager and the farmers.
55. Non-Modular Modules
• Non-modular modules are those through which the
discharge depends upon the head difference between
the distributary and the water course.
Common examples are:
(i) Open sluice
(ii) Drowned pipe outlet
57. Semi-Modules or Flexible
modules
• Due to construction, a super-critical velocity is ensured
in the throat and thereby allowing the formation of a
jump in the expanding flume.
• The formation of hydraulic jump makes the outlet
discharge independent of the water level in water
course, thus making it a semi module. Semi-modules or
flexible modules are those through which the discharge
is independent of the water level of the water course but
depends only upon the water level of the distributary so
long as a minimum working head is available.
• Examples are pipe outlet, open flume type etc.
59. Rigid Modules or Modular
Outlets
• Rigid modules or modular outlets are those through
which discharge is constant and fixed within
limits, irrespective of the fluctuations of the water
levels of either the distributary or of the water course
or both.
• An example is Gibb’s module:
61. Cross Drainage Works
• Irrigational Canals while carrying water from
headworks to crop field, have to cross few natural
drainage streams, nallaha, etc.. To cross those
drainages safely by the canals, some suitable
structures are required to construct. Works
required to construct, to cross the drainage are
called Cross Drainage Works (CDWs). At the
meeting point of canals and drainages, bed levels
may not be same. Depending on their bed
levels, different structures are constructed and
accordingly they are designated by different
names.
62. Necessity of Cross Drainage Works
• The water-shed canals do not cross natural drainages.
But in actual orientation of the canal network, this ideal
condition may not be available and the obstacles like
natural drainages may be present across the canal.
So, the cross drainage works must be provided for
running the irrigation system.
• At the crossing point, the water of the canal and the
drainage get intermixed. So, for the smooth running of the
canal with its design discharge the cross drainage works are
required.
• The site condition of the crossing point may be such
that without any suitable structure, the water of the canal
and drainage can not be diverted to their natural
directions. So, the cross drainage works must be provided
to maintain their natural direction of flow.
64. Types of Cross Drainage Works
• Type I (Irrigation canal passes over the drainage)
• (a) Aqueduct
• (b) Siphon Aqueduct
• Type II (Drainage passes over the irrigation canal)
• (a) Super passage
• (b) Siphon super passage
• Type III (Drainage and canal intersection each other
of the same level)
• (a) Level crossing
• (b) Inlet and outlet
65. Selection of Type of Cross Drainage
Works
• Relative bed levels
• Availability of suitable foundation
• Economical consideration
• Discharge of the drainage
• Construction problems
66. Types of Cross Drainage Works
• Type-I Irrigation canal Passes over the
Drainage: This condition involves the
construction of following:
• Aqueduct
• The hydraulic structure in which the irrigation
canal is taken over the drainage (such as
river, stream etc..) is known as aqueduct. This
structure is suitable when bed level of canal is
above the highest flood level of drainage. In this
case, the drainage water passes clearly below the
canal.
70. Siphon Aqueduct
• In a hydraulic structure where the canal is
taken over the drainage, but the drainage water
cannot pass clearly below the canal. It flows
under siphonic action. So, it is known as
siphon aqueduct. This structure is suitable
when the bed level of canal is below the
highest flood level.
73. Types of Cross Drainage Works
• Type-II Drainage Passes Over the irrigation
Canal.
• Super Passage
• The hydraulic structure in which the drainage
is taken over the irrigation canal is known as
super passage. The structure is suitable when
the bed level of drainage is above the full
supply level of the canal. The water of the
canal passes clearly below the drainage.
76. Siphon Super Passage
• The hydraulic structure in which the drainage
is taken over the irrigation canal, but the canal
water passes below the drainage under
siphonic action is known as siphon super
passage. This structure is suitable when the
bed level of drainage is below the full supply
level of the canal.
79. Types of Cross Drainage Works
• Type III Drainage and Canal Intersect each
other at the same level.
• Level Crossings
• When the bed level of canal and the stream are
approximately the same and quality of water in canal
and stream is not much different, the cross drainage
work constructed is called level crossing where water
of canal and stream is allowed to mix. With the help of
regulators both in canal and stream, water is disposed
through canal and stream in required quantity. Level
crossing consists of following components (i) crest wall
(ii) Stream regulator (iii) Canal regulator.
82. Types of Cross Drainage Works
• Inlet and Outlet
• When irrigation canal meets a small stream or
drain at same level, drain is allowed to enter the
canal as in inlet. At some distance from this inlet
point, a part of water is allowed to drain as outlet
which eventually meets the original stream. Stone
pitching is required at the inlet and outlet. The
bed and banks between inlet and outlet are also
protected by stone pitching. This type of CDW is
called Inlet and Outlet.
84. Selection of Type of Cross Drainage
Work
• The following factors should be considered:
• (i) Relative Bed Level
• According to the relative bed levels of the canal and the river or
drainage, the type of cross drainage work are generally selected
which has been discussed earlier. But some problems may come at
the crossing point
• The following points should be remembered while
recommending the type of work,
• (a) The crossing should be at right angle to each other,
• (b) Well defined cross-section of the river or drainage should be
available.
• (c) At the crossing point the drainage should be straight for a
considerable length.
• (d) The width of the drainage should be narrow as far as possible.
• Considering the above points The C/s can be shifted to the
downstream or upstream.
85. Selection of Type of Cross Drainage
Work
Availability of Suitable Foundation
• For the construction of cross drainage works
suitable foundation is required. By boring
test, if suitable foundation is not
available, then the type of cross drainage work
should be selected to site Condition.
86. Selection of Type of Cross Drainage
Work
Economic Consideration
• The cost of construction of cross drainage
works should be justified with respect to the
project cost and overall benefits of the project.
So, the type of works should be selected
considering the economical point of view.
87. Selection of Type of Cross Drainage
Work
Discharge of the drainage
Practically the discharge of the drainage is very
uncertain in rainy season. So, the structure
should be carefully selected so that it may not be
destroyed due to unexpected heavy discharge of
the river or drainage.
88. Selection of Type of Cross Drainage
Work
Construction of Problems
• Different types of constructional problems may arise
at the site such as sub soil water, construction
materials, communication, availability of land etc. So
the type of works should be selected according to the
site condition.
89. Questions
• What do you understand by a fall in
canal? Why it is necessary?
• What are the functions of a canal head
regulator?
• Explain functions of cross regulator and
distributory head regulator.
• Write a S.N. on Types of Canal Falls
90. References
• Irrigation Engineering & Hydraulic Structures
– By Prof. Santosh Kumar Garg
– Khanna Publishers
• Internet Websites
• http://www.uap-bd.edu/
• Lecture Notes By: Dr. M. R. Kabir
• Professor and Head, Department of Civil Engineering
Department
• University of Asia Pacific (UAP), Dhaka