CE010 605 Water Resources Engineering
QUESTION BANK
(Questions from Previous Year University Question Papers)
Module 1
1. Define irrigation.
2. What is the necessity of irrigation?
3. Write a note on scope of irrigation.
4. What is meant by a multipurpose river valley project?
5. Discuss in brief the benefits and ill-effects of irrigation.
6. Write an essay on ‘history of irrigation developments in India’.
7. Discuss in brief various methods of surface irrigation.
8. What is contour farming? Compare it with wild flooding method.
9. Write a note on sub-surface irrigation.
10. Describe border strip method of irrigation.
11. Write a note on sprinkler method of irrigation.
12. Compare surface irrigation with sub-surface irrigation.
13. Discuss in brief the functions of irrigation water.
14. What are the standards of irrigation water?
15. What are the various forms of soil moisture?
16. What do you mean by available moisture?
17. Write short notes on:
a) Saturation capacity
b) Field capacity
c) Wilting point and
d) Optimum water
18. What is meant by evapotranspiration? How is it determined?
19. Explain the terms duty and delta. Derive a relationship between the two.
20. What are the factors affecting duty? How can duty be improved?
21. Define the following:
a) GCA
b) CCA
c) Kor depth
d) Kor period
e) Outlet factor
f) Capacity factor
g) Nominal duty
h) Open discharge
i) Rabi and Kharif crops
22. What is crop rotation? What are its advantages?
23. Discuss various methods of assessment of irrigation water.
24. What do you understand by the following terms:
a) Crop ratio
b) Overlap allowance
c) Capacity factor
d) Full supply coefficient
25. A field channel has culturable commanded area of 2000 hectares. The intensity of irrigation for gram is 30% and for wheat is 50%. Gram has a kor period of 18 days and kor depth of 12cm. While wheat has a kor period of 15 days and a kor depth of 15cm. Calculate the discharge of field channel.
26. The discharge available from a tube well is 120m3 per hour. Assuming 3200 hours of working for a tube well in a year, estimate the culturable area that is tube well vcab command. The intensity of irrigation is 50% and the average depth of Rabi and Kharif crops is 48cm.
27. A water course command an irrigated area of 800 hectares. The intensity of irrigation of rice in this area is 50%. The transplantation of rice crop takes place in 15 days and total depth of water required by the crop is 60cm on the field during the transplantation period, given that the rainfall on the field during this period is 15cm. Find the duty of irrigation water for the crop on the field during transplantation, at the head of the distributary, assuming the losses of water to be 20% in the water course. Also calculate the discharge required in the water course.
28. The left canal of a tank irrigation scheme carries a discharge of 10 cumecs and has a culturable commanded area of 800 hectares. The intensity of Rabi crop is 70% and the base period is 110 days. The right canal of this scheme carries a discharge of 24 cumecs and has a culturable commanded area of 15000 hectares. The intensity of Rabi crop is 80%and the base period is 110 days. Compare the efficiency of two canal system.
29. Wheat is to be grown in field having a field capacity equal to 27% and the permenant wilting point is 13%. Find the storage capacity in 80 cm depth of soil, with the dry unit weight of the soil is 1.5 gm/cc. if the irrigation water is to be supplied when the average soil moisture false to18%, find the water depth required to be supplied to the field if the field application efficiency is 80%. What is the amount of water needed at the canal outlet if the water lost in the water course and the field channel is 15% of the outlet discharge.
30. The gross command area for a distributory is 10000 hectares, 75% of which can be irrigated. The intensity of irrigation for the rabi season is 60% and that for kharif season is 30%. If the average duty at the head of distributory is 2500 hectares/cumec for rabi season and 1000 hectares/cumec for kharif season, determine the discharge required at the head of the distributory from average demand consideration.
31. A certain crop is grown in an area of 3000 hectares which is fed by a canal system. the data pertaining to irrigation are as follows.
Field capacity of soil =26%
Optimum moisture =12%
Permanent wilting point =10%
Effective depth of root zone =80cm
Relative density of the soil =1.4
If the frequency of irrigation is 10 days and the overall efficiency is 23% , find (i)the daily consumptive use (ii) the water under discharge in m3/sec, required in the canal feeding the area.
32. The consumptive use requirements of a crop are 0.2cm per day for days 1 to 15, 0.3cm per day for days 16 to 40, 0.5cm per day for days 41 to 50 and 0.1cm per day for days 51 to 55. Effective rainfall of 3.5cm, distributed uniformly during 36th and 45th days (both inclusive) is predicted. Compute the total quantity of water (in cu.m) to be delivered to a 50 hectares plot for the whole crop season with a pre-sowing requirement of 5cm of water.
33. (a) Define and explain the following terms as used in relation to water requirement of crops. (i) Base period, (ii) Intensity of irrigation and (iii) Cash crops
(b) What do you understand by duty of canal water and what is its importance. Explain how duty differs from at the head of a watercourse and that at the head of a canal bringing water to the watercourse.
(c) Mention the approximate values of duty and delta for Rice, Cotton and sugarcane in A.P.
34. What is irrigation engineering?
35. What are the benefits of irrigation?
36. What are the disadvantages of irrigation?
37. What is the purpose of irrigation?
38. Define crop ratio.
39. What is meant by overlap allowance?
40. Define arid and semiarid regions.
41. Define wilting coefficient.
42. What is meant by consumptive use of water?
43. What are the factors affecting consumptive use of water?
44. Define duty.
45. Define delta.
46. Define base period.
47. Define crop period.
48. What are the factors affecting duty?
49. What are the methods for improving duty?
50. What is the gross command area and culturable command area?
51. Define saturation capacity and field capacity.
52. Explain the necessity and scope of irrigation
53. Discuss in detail the benefits and ill-effects of irrigation
54. Define duty and explain in detail the various factors affecting duty. How can duty be improved? Explain.
55. A watercourse has culturable commanded area of 2600 hectares, out of which the intensities of irrigation for perennial sugar-cane and rice crops are 20% and 40% respectively. The duty for these crops at the head of watercourse is 750 hectares/cumec and 1800 hectares/cumec respectively. Find the discharge required at the head of watercourse if the peak demand is 20% of the average requirement.
56. The base period, intensity of irrigation and duty of various crops under a canal system are given in the table. Find the reservoir capacity if the canal losses are 20% and reservoir losses is 12%.
57. What do you understand by crop rotation? What are its advantages?
58. Find the capacity of a soil for the following data:
Root zone depth = 2 m
Existing water content = 5%
Dry density of soil = 1.5 g/cm3
Water applied to the soil = 500 m3
Area of plot = 1000 sq.meters.
Water loss due to evaporation = 10%
60. After how many days will you supply water to soil (clay loam) in order to ensure efficient irrigation of the given crop, if
(i) Field capacity of soil = 27%
(ii) Permanent wilting point = 14%
(iii) Density of soil = 1.5 g/cm3
(iv) Effective depth of root zone = 75 cm
(v) Daily consumptive use of water for the given crop = 11mm
61. A water course has a culturable commanded area of 1200 hectares. The intensity of irrigation for crop A is 40% and for B is 35%, both the crops being Rabi crops. Crop A has a Kor period of 20 days and crop B has Kor period of 15 days. Calculate the discharge of the water if the depth for crop A is 10 cm and for B it is 16 cm.
62. What are the types of irrigation?
63. What do you mean by flow irrigation?
64. Define lift irrigation.
65. Define perennial irrigation
66. Define inundation irrigation
67. Define direct irrigation.
68. What do you meant by storage irrigation?
69. Define combined irrigation.
70. What are the different classifications of method of irrigation?
71. What do you mean by uncontrolled and controlled flooding?
72. What are the basic requirements for adaptation of any irrigation method?
73. What do you mean by free flooding?
74. Where contour laterals are applicable?
75. Write about the advantages of furrow irrigation.
76. Under which favourable conditions the sub-surface irrigation is practiced?
77. Where sprinkler irrigation is more useful?
78. Write about the advantages of sprinkler irrigation.
79. Write about the limitations of sprinkler irrigation.
80. Write about the advantages of drip irrigation
81. Write about the disadvantages of drip irrigation.
82. Write a note on sub-surface irrigation, state clearly the conditions under which this method is suitable. What are the essential requirements for a successful sub-surface irrigation?
83. Describe border strip method of irrigation. Derive the expression for the time required to cover a given area by this method, for a given rate of discharge and the rate of infiltration of water in the soil.
84. Find the time required to cover an area of 0.1 hectares when a tube well is discharge at the rate of 0.03 cumecs for irrigating Rabi crops. Average depth of flow is expected to be 7.5 cm. Average infiltration rate for the soil may be taken as 5 cm / hr. and also find maximum area that can be irrigated by the available discharge of 0.03 cumecs.
85. Explain in detail about sprinkler method of irrigation and how far it is suitable in Indian conditions.
86. Write a note on drip irrigation. Write about the advantages and disadvantages of drip irrigation system.
87. Define surface irrigation. Why it is widely practiced method of irrigation? What are the advantages and disadvantages of the method?
88. Write a note on free flooding and contour laterals.
89. Describe check flooding and basin flooding.
90. Write about zigzag method and contour farming.
91. Describe furrow method of irrigation.
92. What are types of irrigation?
93. Define the following terms (i)Field capacity(ii)Wilting point(iii)Permanent Wilting point (iv)readily available soil moisture.(v) Evapotranspiration.
94. List the various modes of distribution of water in the field for irrigation.
95. A stream of 125liters/sec was diverted from a canal and 100liters/sec. was delivered to the field. An area of 1.6 hectares was irrigated in 8 hours. The effective depth of root zone was 1.7metres.The run-off loss in the field was 420m3. The depth of water penetration varies linearly from 1.7m at the head end of the field to 1.3m at the tail end. Available moisture holding capacity of the soil is 20 cm per metre depth of soil. Existing moisture content was 50% of the moisture holding capacity. Determine (i) water conveyance efficiency (ii) water application efficiency (iii) water storage efficiency (iv) water distribution efficiency.
96. Briefly discuss any one method for estimating crop consumptive use. State the equation used with the assumptions.
97. An irrigation canal has gross command area of 80,000ha of which 90% is irrigable. The intensity of irrigation for Kharif season is 30% and for Rabi season is 60%.Find the discharge required at head of canal, If the duty at head is 800 ha/cumec for Kharif season and 1700ha/cumec for Rabi season.
98. Differentiate between catchment area and command area.
99. Differentiate between flow duty and quantity duty.
100. Discuss the factors influencing the water requirements of crop.
Module 2
1. Explain hydrological cycle.
2. What is precipitation? Explain various types of precipitation.
3. Explain any one type of automatic rain gauge.
4. Evaporation is indirectly a cooling process. Justify the statement. Discuss the factors affecting evaporation.
5. The rate of rainfall for the successive 30 min period of a 3-hour storm are: 1.6, 3.6, 5.0, 2.8, 2.2, 1.0 cm/hr. The corresponding surface runoff is estimated to be 3.6 cm. Establish the ø-index. Also determine the W-index.
6. How can IUH be derived from S-curve
7. The ordinates of 6-hour UH are given below. Derive the ordinates of 12-hour UH without resorting to the S-curve technique.
Time (hr): / 0 / 6 / 12 / 18 / 24 / 30 / 36 / 42 / 48 / 54 / 6012-hr UGO(cumec) / 0 / 5 / 13 / 30 / 35 / 32 / 20 / 14 / 8 / 4 / 0
8. Define `rainguage density' and explain how you would determine the optimum number of rainguages to be erected in a given basin.
9. Neighbouring raingauge stations A, B, C, D, E and F have normal annual rainfalls of 610, 554, 468, 606, 563 and 382mm respectively. During a storm, stations B, C, D, E and F have reported rainfalls of 22, 29, 35, 13 and 25 mm respectively and station A? did not report as it was inoperative. Estimate the missing storm rainfall at `A' by Arithmetic average method and the Normal ratio method.
10. Define Hydrology.
11. Define Hydrologic cycle.
12. What is a Catchments area?
13. Write short note on Divide.
14. Define Front
15. Write short note on cyclones.
16. Define Anticyclones.
17. Explain Thunder storm.
18. Define Tornadoe.
19. How does the average intensity of rainfall obtained from mass curve.
20. Define rainfall intensity.
21. Write short note on rainfall hyetograph.