Canal

Third year civil engineering
subject- WRE

1. CANALS Prof . M. B Chougule ( department of civil engineering) DKTE’S Y.C.P Ichalkaranji

2. . canal A canal is defined as an artificial channel constructed on the ground to carry water from a river or another canal or a reservoir to the fields. CLASSIFICATUION OF CANAL A)Classification based on alignment: 1) ridge canal 2) ridge canal 3) side long / side slope canal. B)Classification based on position: 1) Main Canal 2) Branch Canal 3) Major Distributary 4) Minor distributary 5) Water Course 6) Head Work

3. . CONTOUR CANAL:- when canals are to be laid in hilly area it is not possible to align along which is at top of hill. In such cases canals are aligned generally along contours. The canal taking off from reservoir follows contours alignment such that canal which is aligned parallel to the contours of area is known as contour canal. Contour canal have large number of CD works but no falls. A contour canal can irrigate only one side as ground level at other side is quite high. Contour canals need not to follow same contour along its length. To contour canals longitudinal slope is given to enable the water to flow by gravity.

4. . Advantages:- A) suitable in hilly area. B) to contour canal longitudinal slope is given to enable the water to flow by gravity. Disadvantages:- A) large number of cross drainage works. B) can irrigate only one side. RIDGE CANAL/ RIDGE ALIGNMENT:- it is also called as watershade canal. These types of canal are generally laid along ridge or naturally watershade line as canal runs on watershade it can irrigate on both sides and thus irrigates area on sides. These canals are very economical. No CD works is required.

5. . Advantages:- A) it can irrigate on both sides. B) economical. C) no CD work Disadvantages:- A) velocity of water needs to be controlled. B) scouring of bed due to higher velocity.

6. . SIDE SLOPE CANALS:- In this type of alignment canal is not aligned along either ridge or contour but it is aligned across contour. These canals runs nearly parallel to natural drain similar to contour canal. It also irrigates area on only one side. These type of canal are not intercepted by cross drainage works.

7. . Canal network:-

8. . i ) Head regulator : When the canals are branched or taking off from reservoir or main canals in the distribution system head regulator is provided at the head of canal, to divert necessary discharge from reservoir to canal or main canal to branch canal, to control, regulate or measure the discharge, to control the silt entry in the taking off canal ,to stop the supply of water when not needed (end of rotation) or for repair at down stream. (ii) Cross regulator : When it is required to raise the water level in main canal in order to regulate the flow in branch canal ,to stop the flow in case of repair on down stream. To divert silty overflow water in to the near by river or stream during flood control cross regulator is provided. (iii) Escap e: At the end of main canal or to allow escape of the silty water into the waste channel and then to natural drain during rainy season escapes are provided. (iv ) Outlets: To admit water into the, distributaries, minors, water courses, field channels etc. Out lets

9. PARTS OF CANAL SYSTEM:- A) main canal B) branch canal. C) major distributor. D) minor distributor. E) water course. c.

10. . A) main canal:- the canal taking off from a river or reservoir i.e. from source is called as main canal. Function is to carry the total water and to distribute it to canal system. It is largest canal in system and no direct irrigation is normally done from main canal. B) branch canal:- it is canal takes off from main canal on either side. Very little direct irrigation is done from them. These canal act as a feeder canals for major distributor. The discharge capacity of branch canal is usually varies from 5 to 25 cumec . It helps to make irrigation water available in different parts of distribution.

11. . C) major distributor:- it is generally takes off from main canal which supplies water to other distributor. The discharge capacity of major distributor varies from 0.25 to 5 cumec in some cases it may be 10 cumecs . These are generally used for direct irrigation and their main function is to distribute water to water courses. D) minor distributor/ minor:- minor distributor generally takes off from major distributor or from main canals or another distributor and supplies water to water course. Its discharge capacity is less than 0.25 cumecs . These are also used for direct irrigation. E) water course:- these are small channels which takes water from the outlet of distributor or minor distributor and supply it to the agricultural fields.

12. . These are owned constructed controlled and maintained by cultivators. Some times these are constructed by the government on behalf of irrigators but its maintenance is carried out by irrigators only. F) head work:- the works those are constructed to store, divert and control the river water regulate the supply in to the canal.

13. . FIXING ALIGNMENT OF CANAL:- Following points should be considered while fixing the alignment of canal:- 1. Along the alignment of canal, the cross – drainage works should be minimum. 2. The alignment of canal should be such that, water should flow under gravity. 3. The canal alignment should be such that, the quantity of earthwork in cutting should be equal to the quantity of earthwork in filling. 4. The alignment of canal should be such that, it can cover maximum command area. 5. The length of main canal should be minimum. 6. The number of curves should be minimum. 7. The alignment should not made in a rocky cracked strata.

14. . CROSS SECTION OF CANAL IN, FILLING AND IN PARTIAL CUTTING & FILLING:- in cutting:-

15. Cross Section of Canal in Partial Cutting and Filling

16. . CANAL LINING:- means providing impervious thin layer of 2.5 to 15 cm thickness to protect the bed and sides of canal. Generally of RCC or CC bricks, Stones etc. Materials used in canal lining. 1) Cement Mortar, lime Mortar 2) Concrete 3) Stone masonry 4) Brick 5) Sodium carbonate 6) Asphalt 7) Precast concrete block

17. . Types of canal lining:- a. Cement concrete Lining: Concrete as a lining material gives excellent hydraulic properties. The thickness of lining is governed by the requirement of imperviousness and structural strength. The thickness is provided is from 5 to 10 cm for M15and 7.5 cm to 15 cm for M10 concrete. The concrete used for lining has mix ratio 1:4:8 or 1:3:6 or 1:4:6. b. Shotcrete Lining: Mixture of cement and sand (1:4) is shot at the sub grade through a nozzle. The thickness of this type of lining varies from 2.5 to 6.5 cm. Shotcrete consumes large amount of cement. Shotcrete can be placed on irregular subgrade and fine dressing of subgrade is not required. c. Precast concrete Lining: This type of concrete lining consists of precast slabs usually 90 cm x 30 cm in size. The thickness of each slab is from 5 to 6.5 cm. The blocks are manufactured with an interlocking arrangement. The slabs are laid on well prepared and compacted subgrade . d. Cement mortar lining: Thickness for this of lining is kept from 1 to 4 cm. A large amount of cement is consumed in this type of lining and it is very costly.

18. . e. Brick Lining: This type of lining consists of single or double layer of brick masonry or a layer of brick masonry followed by a layer of tiles laid is mortar. The first layer is laid on 12 mm layer of 1:6 cement mortar. A 12 mm thick layer of plaster in 1:3 cement mortar is laid over the first layer. Then the second layer is laid over it in 1:3 cement mortar. f. Asphaltic lining : It is controlled mixture of asphalt and grade aggregate mixed and placed at a high temperature of 200c and covered with 30 cm layer of earth material for a protection. The mix is placed either by hand or by equipment similar to that concrete. g. Clay Puddle Lining: Clay puddle is produced from by first exposing clay to weathering. It is then mixed with water to bring it to the saturation and pugged thoroughly by trampling under man’s or cattle’s feet. This thickness of lining is 30 cm. It is then protected by layer of earth material. h. Sodium carbonate Lining : The mixture consists of clayey soil (10%) and sodium carbonate (6%). The thickness of lining is kept as 10 cm. this type of lining is used for small canal and water course.

19. . i . Stone block lining: This consists of undressed stone block set in mortar laid over prepared sub grade. The lining is able to check seepage effectively but has a considerable resistance to flow of water. j. Pre-fabricated light weight membrane: They are matted fibers of asbestos or jute and are coated with asphalt. It is laid on a smooth and prepared subgrade , and is covered with layer ofearth material. k. Bentonite and clay membrane: This consists of bentonite or clay blanket 4 cm thick laid over a prepared subgrade and covered with earth. l. Road oil lining: The road oil sprinkled on subgrade in thickness of about 1.5 mm is sufficient enough to saturate subgrade to depth 8 cm. the subgrade is then rolled so that oil enters the soil pores.

20. . Purposes of lining : 1. To reduce the seepage losses in canal. 2. To prevent scouring of bed sides. 3. To improve the discharge of canal by increasing the velocity of flowing water. 4. To prevent water logging. 5. To increase the capacity of canal. 6. To increase the command area. 7. To control the growth of weeds. 8. To protect the canal from the damage by flood.

21. . Advantages : 1. It reduces the loss of water due to seepage and hence the duty is enhanced. 2. It controls the water logging. 3. It provides smooth surface and hence the velocity of flow can be increased. 4. Due to the increased velocity the discharge capacity of canal is also increased. 5. Due to the increased velocity the evaporation also is reduced. 6. It eliminates the effect of scouring in the canal bed. 7. The increased velocity eliminates the possibility of silting in the canal bed. 8. It controls the growth of weeds along the canal sides and bed. 9. It provides the stable section of the canal. 10. It prevents the sub soil salt to come in contact with the canal water. 11. It reduces the maintenance cost of canal.

22. . Disadvantages 1. The initial cost of canal lining is very high. 2. It involves much difficulty for repairing the damaged section of lining. 3. It takes too much time to complete the project work. 4. It becomes difficult if the outlets are required to be shifted or new outlets are required to be provided because dismantling of the lined section is difficult 5. there might be chances of leakage through joint.

23. . properties of good lining material : 1) Water tightness 2) Low cost & subsequent less maintenance cost 3) Strength & durability 4) Prevention of weeds growth 5) Ease of constructing with local material 6) the lining material should be should be such that it can be easily repaired. 7) it should be able to resist the growth of weeds and attack of burrowing animals. 8) the surface of lining material should be smooth for higher hydraulic efficiency.

24. . Define balancing depth in canals:- The depth of particular cross section in which the amount of cutting and filling is equal is known as balancing depth. This section is economical. It is found out by following procedure:- Let h=vertical height of top bank from bed of canal. b= bed width of canal. t= top width of canal bank. z:1= side slope of canal in cutting. n:1= side alope of bank in filling. d= full supply depth of canal.

25. . Area of cutting= by + zy² Area of filling = 2 [ (h-y)t + h(h-y)² ] Equating area of cutting to area of filling:- Y( b+zy )= 2 [ (h-y)t + h(h-y)² ] As per design consideration In cutting side slope= 1:1 And in filling = 1.5:1 Putting n =1.5 and z= 1 Y= depth of cutting The depth y from ground line and bed level is calculated.

26. . HYDRAULIC DESIGN:- In hydraulic design of canal following values are to be found out: 1) bed width (b) 2) velocity (v) 3) supply level (d) 4) afflux etc. All these factors depends on :- 1) Design discharge (R)/(Q) 2) bed slope (S) 2) coefficient of rugocity (N) 4) side slope (Z) 5) Side slope in cutting (n) Bed slope:- steeper the bed slope higher or more the velocity. Velocity should be such that it neither scour the bed and does not allows the silt to deposit such velocity is known as ‘ critical velocity’ (V₀)

27. . it is given by, (V₀) = 0.55d² ( Kennedy equation ) (V₀) = critical velocity in m/s² d= depth of flow in m. Critical velocity ratio:- It is the ratio of actual velocity (v) to the critical velocity. C.V.R= V/ V₀ ( for unlined canal its value is in between 0.9 to 1.2) Coefficient of rugosity (N):- The general value adopted are: For stone lining - 0.022 For unlined canal – 0.030 For concrete canal – 0.01 to 0.016

28. . Side slope for design:- It depends on lining of canal, whether the canal is lined or unlined. 1) in case of lined canal actual side slope to which lining is laid should be adopted. 2) for unlined canal it is taken as 1:0.5 design procedure:- for unlined canal- 1) adopt side slope 1V = 0.5H and N=0.03 2) assume ratio of b/d between 2 to 4 (b=4, d=1) 3) by using trial and error method assume a set of ‘b’ & ‘d’ & calculate values of area (A) perimeter (P), ( R) and velocity (V) by using following equation A=(b- zd ) ∙ d

29. . P= b + 2d √ 1+ z² R= A (m) P V= 1 R⅔ S½ ( S= Bed Slope) N calculate value 0.64 V₀= 0.055d If it is less than 0.9 reduce depth and if it more than 1.2 increase depth. After satisfying with above step:- find out discharge Q= AV ( cumecs ) And after that check your calculated discharge if it is in the range if design discharge assume design is ok otherwise repeat with deiferent values of b and d

30. . FOR LINED CANAL:- 1) take side slope as 1:1 and value of N as per type of lining. 2) use condition of economic section. i.e. b=2d √(1-z²) -2 zd and R= d/2 3) find out values of A,V & R (from above formulea ) 4) and Q design = A ∙ V from this value of b and d can be obtained.

31. . Maintenance work of canal: Removal of silt: The silt should be removed properly during closure period either manually or with machines, and if it is more than canal should be closed and then silt should be removed. silt can be removed by increasing velocity of canal water by addition of more water in it. It also removed by providing silt ejector in canal.   2. Weed growth: weed affects efficiency of canal and hence weeds and plants should be removed from canal from their roots. 3. Strengthening of canal bank: The banks should be strengthened properly. If any holes made by insects are found, it should be properly closed. Leakage if any found should be properly treated, if scouring of banks noticed proper measures should be adopted. 4. Maintenance of service road: Canal roads are inspected after Heavy rains and necessary repair. Work should be started if found any deterioration. 5. Overflow of canal banks: After rainy season proper attention is given towards canal banks as banks may get deteriorated due to heavy rains or flood and then apply necessary treatment.  

32. . C. D. work: The work constructed to pass the canal water safely under/over the drainage water is called as cross drainage work. or Irrigation structures constructed for carrying the canal water safely over or under the drainage water are called cross drainage work. When a canal is taken off from the reservoir, it meets various natural drainages before reaching the watershed line. In this range cross drainage works are required to be constructed. Different types of C.D. works: i . Aqueduct ii. Super passage iii. Level crossing iv. Inlet and outlet

33. . Selection of suitable type of CD work. The bed level of irrigation canal and natural drainage. Economy of the construction. The total discharge carried by canal and drain. If the bed level of canal is above HFL of the drain then as aqueduct should be preferred if drainage is of medium size culvert should be preferred. If FSL of canal is below the drainage bed super passage should be provided. When sufficient headway is not available even by changing alignment of canal, syphon aqueduct should be preferred. When drain bed level is lower and FSL of canal higher than drain bed level, canal syphon or syphon super passage should be preferred. When Canal & drain bed level are practically at the same level and the flow is for short period without much silt, level crossing should be preffered .

34. . i ) Aqueduct: a) The irrigation structure constructed for passing the canal water safely over the drainage water is called an aqueduct. b) Aqueducts are constructed where the discharge of drain is more in comparison to canal discharge and when canal bed level is sufficiently above HFL in the drain.

35. . AQUEDUCT IS FURTHER CLASSIFIED AS:- 1) pipe aqueduct 2) box culvert/ irrigation slab drain 3) masonry aqueduct 4) siphon aqueduct 5) siphon culvert 6) irrigation culvert

36. . Pipe aqueduct:- in this case canal water is taken through pipe. In the pipeline aqueduct the diameter of pipe depends on discharge. It is adopted when canal section is very small and width of drain is more. Box culvert:- the culvert are similler to ordinary bridges only differance is that the road is replaced by canal. Culverts are provided under following situation. When stream discharge is less as compaired to canal discharge. In culverts thickness of slab is generally 30 to 50 cm. It consist of abutment of UCR or concrete and piers accordingly to necessity.

37. . Masonry aqueduct:- in this type of aqueduct it is constructed with masonry and the width of drainage is very large and drain water passes through it. Roadway is provided on one side of canal and inspection path on other side. Wing wall are also provided on upstream and downstream side. Siphon aqueduct:- when HFL of the drainage is above or touches CBL ( canal bed level ) but lower than FSL and drainage is small this type of aqueduct is preferred. In this type canal is at higher level than the drainage. It consist of pipe aligned normal to the canal at sufficient depth below CBL. The canal is flumed and taken cross through trough. The water flows under hydrostatic pressure through this depression in order to avoid deposition of silt a small slope is provided to give self cleaning velocity.

38. . Siphon culvert:- in this type of culvert the bed of drainage is depressed. These are not preferred if discharge through drainage is more. Irrigation culvert:- these culvert belongs to class of cross drainage work. These are located at nallaha , strem , torrent, river where it crosses the canal alignment. These are preferred when width of drainage varies from 2.5 to 16m. Arch roof is provided instead of R.C.C slab.

39. . ii) Super passage: a) When the drainage water at a point of crossing is taken over the canal, the structure is called super passage. b) Super passages are constructed when the discharge is small in comparison with the canal discharge and when sufficient clearance is available between the FSL of canal and drain bed. It is classified as: 1) pipe super passage 2) siphon super passage

40. . Pipe super passage:- in this case pipe is provided for carrying drainage water over the canal. Pipe super passage is provided only if discharge is less. The main disadvantage of these type of super passage is that if silt is deposited it is difficult to clear it off. Siphon super passage:- in this type the bed of canal is depressed so that FSL should not touch the roof of water way.

41. . iii) Level crossing: a) When the canal bed level and drain bed level practically the same, drain water is taken into the canal and it is allowed to intermingle with the canal water. Such type of cross-drainage work is known as level crossing. b) It is constructed where RL of canal bed and RL of natural drain are practically the same. Also when the discharge of drain and that of the canal is approximately of the same magnitude, duration of the flood in drain is short and no other structure is economically feasible.

42. . iv) Inlet and outlet: a) Inlet admits water of stream into the canal and it flows mixed with canal water and then excess discharge is allow to pass through outlet. b) The capacity of inlet and outlet must be same and sides and beds of canal must be protected by stone pitching.

43. .

44. . 2- Suggest suitable type of cross drainage works with neat labeled sketches (any two). 1.Nallah bed level is well above canal FSL 2. Nallah and canal bed levels are almost equal with heavy flood discharge in Nallah 3. Canal Bed Level = 435.0 m . Nallah bed level = 433.0 m . Nallah HFL = 436.0 i.Nallah bed level is well above canal FSL :-Super passage

45. . ii. Nallah and canal bed levels are almost equal with heavy flood discharge in Nallah

46. . iii.Canal Bed Level = 435.0 m Nallah bed level = 433.0 m Nallah HFL = 436.0

47. . 3- Suggest the suitable type of CD work and draw the sketch of it under each of the following sititutions . i ) Canal bed level and Nala Bed level are same ii) Canal bed level is above HFL of Nala iii) Nala bed level is above FSL of canal. iv) HFL of Nala is between FSL of canal & bed level of Canal. i ) Canal bed level and Nala Bed level are same:

48. . 1. The RL of canal bed & RL of Nala are pratically same. 2. The discharge of Nala & that of canal is app of the same magnitude. 3 No other structure is economically feasible. ii) Canal bed level is above HFL of Nala

49. . 1. The discharge of Nala is more in comparison to Canal discharge. 2. The bed level of canal is sufficiently above the high flood level of Nala . iii) Nala bed level is above FSL of canal

50. .  1. The bed level of drainage is above the full supply level of canal. 2. The water of the canal passes clearly below the drainage . iv) HFL of nala is between FSL of Canal and bed level of canal

51. . 1. The nala bed is at higher level than FSL of canal. 2. The clearance between Nala bed * FSL of canal is either insufficient or the Nala bed is lower than FSL of canal but higher than the bed of canal.

52. . Canal falls and rapids:- Canal fall and rapids are constructed when it is necessary to lower bed so as to avoid heavy banking. This situation occurs when ground slope is steeper than bed gradient. Falls should be located on downstream of take off.

53. . Falls:- if this lowering is achieved at one section vertically downward the structure is called as fall. Rapid:- if the lowering is achieved in small length by providing steep slope it is called rapid or chute. Drop:- the vertical distance between upstream water level and downstream water level in canal is called as drop. The falls are classified into following types:- 1) ogee fall 3) vertical fall with cistern. 2) vertical stepped fall 4) trapezoidal notch fall 3) rapid fall 1. To lower the canal bed level according to the slope of ground 2. To maintain the designed bed slope of the canal. 3. To avoid heavy banking. 4. It gives the consideration of economy in cost of excavation of channel.

54. . Escapes:- Irrigation structure constructed to escape excess water from the canal to some natural drainage are called escape. These are located at 5 to 10 km along major canal. Escape consist of head wall parallel to the bank. It has opening to allow canal flow water through pipe and gate. The other end is attached to waste canal which is lined for some distance. This waste canal takes discharge to nearby valley. The escape are provided at a distance depending upon importance of canal Necessity 1. To remove surplus water from canal into some natural drain or nallah . 2. To avoid damage to the channel by surplus water. 3. To provide safety valves of canal 4. To save downstream section of canal from overflow of banks.

55. . The escapes are classified as:- 1) scouring escape- provided in head reaches of main canal to scour out the deposited bed silt 2) surplus escape:- provided to dispose off surplus water from canal. 3) tail escape:- provided at tail of branch canal

56. . Cross regulator:- The regulator constructed in or across parent canal on downstream of major branch or distribution head regulator is called as cross regulator. Function :- 1. To control flow of water in the canal system. 2. To feed the off taking canals. 3. To enable closing of canal the canal branches on the downstream side. 4. To provide roadway for vehicular traffic. For cross regulator pier & abutment with grooves are constructed parallel to parent canal and vertical lift gates are fitted in to these grooves.

57. . Canal outlets:- it is a structure constructed to allow water in to field canals or ditches through which water is supplied to water course. It may be used for measurement of discharge supplied to cultivator. The discharge is less than 0.085cumecs. It plays as important role in equal distribution of water. Function:- 1. To admit water from the distributor or parent channel to field channel. 2. To draw proportionate quantity of silt.

58. . Requirements of good canal outlet:- 1) it should be simple in construction as well as maintenance. 2) it should be cheap, strong and durable. 3) it should draw proportionate water according to discharge. 4) it should not be easily tempered by cultivator to increase in the water course. 5) it should draw proportionate silt. Types of outlet:- 1) non modular outlet 2) semi modular outlet/ flexible outlet 3) modular outlet/ rigid module.

59. . 1) non modular outlet:- The discharge through non modular outlet depends on the difference in water level of distributor and water course. The most commonly used type of the outlet is the non modular outlet also called as pipe outlet.

60. . 2) semi modular outlet/ flexible outlet:- The discharge in this outlet depends on the water level in the distributor only and is independent of water level in water course. Kennedis venturi flume are the example of semi modular type outlet. 3) modular outlet/ rigid module:- Module is type of structure specially designed to maintain discharge irrespective of water level in distributor and the water course. The gibb’s module is the best example of modular type outlet.

61. . Canal regulation work:- The masonry structure constructed in or across the canal to regulate the discharge, full supply level and velocity in canal is called as canal regulation work. It includes:- 1) head regulator 2) cross regulator 3) canal escape 4) canal fall and rapids 5) outlets

62. . Head regulator : In the distribution system canals are branched from main canals to this point or junction to this point. Masonry structure constructed is called the head regulator. It divert necessary discharge from reservoir to canal or main canal to branch canal, to control, regulate or measure the discharge, to control the silt entry in the taking off canal, to stop the supply of water when not needed (end of rotation) or for repair at Function:- 1) it regulates the discharge. 2) it divert proportionate quantity of silt to off taking canal. 3) it helps to measure discharge. Head regulator consist of rectangular opening with barrels running through bank. The upstream abutment is given curved shape while it is normal on downstream side to divert water and silt.

63. . Water logging: The condition of soil when it becomes completely saturated with water and becomes unfit for the growth of plants is called water logging. Effects of water logging:- Absence of areation of soil in the root zone of plant. Difficulties in the process of cultivation. Growth of water- weeds. Increase in the level of salts. Restriction in root growth. Lower soil temperature. Plant diseases Difficult in field operation. Crop yield get reduced.

64. . .: Causes of water logging i ) Over irrigation by farmers under wrong impression that more water will fetch more crop yield. ii) Bad tilling creating depressions and ponds in the field. iii) Improper land grading. iv) Seepage through vast network of unlined canals. v) leakage through badly maintained structures and cracks. vi)Irrigation of unsuitable soils (deep clayey soil) vii)Inadequate surface drainage which leads to stagnation of water in the area viii)Obstruction to natural drainage due to road, railway or canal embankment which leads to flooding of land and then water logging. ix) Natural obstruction to the flow of ground water. x) Seepage through reservoir leads to water logging on d/s and u/s side.

65. . Remedial measures: i )Provide an efficient drainage system to permit quick flow of rain and reduce the water logging. ii)Reduce the percolation from canals –by Lining of irrigation channels to make canal surface impervious, Lowering of full supply level of irrigation channel to reduce seepage loss from embankment. Construct intercepting drains to collect the seepage water and carry it to nearby natural stream quickly in short period iii)Restrict the irrigation by educating the people regarding water requirement of crop ,wastage of water , modern and efficient methods. iv)Remove obstruction in natural drainage.v )Prevent seepage of water from reservoir. vi)Reduce ground water storage by pumping out water from wells. viii)Apply sprinkler and drip or any other micro irrigation system.

66. . Following are the precautions to prevent a land from getting waterlogged: i ) Reducing the intensity of irrigation ii) Providing intercepting drains iii) Lining of canals iv) Providing intercepting drains v) Improving natural drainage of the area vi) Providing intercepting drains vii) Provision of an efficient drainage system viii) Improving natural drainage of the area