Irrigation Engineering Multiple Choice Questions on “Canal Irrigation System – Alluvial and Non-alluvial Canals”.
1. Which of the following statement is not correct about alluvial soils?
a) It is formed by sediment deposition of silt from the flowing water
b) The area of alluvial soil is even
c) It has a flat surface slope
d) Hard foundations are generally available
Answer: d
Clarification: The process of silt deposition over a long period of time resulting in the formation of soil is called alluvial soil. It has a flat surface slope and even area. Hard foundations are generally not available in this kind of soil.
2. Non-alluvial soils are generally found in a mountainous region.
a) True
b) False
Answer: a
Clarification: The disintegration of mountainous rocks over a period of time resulting in the formation of a rocky plain area called non-alluvial soils. It has uneven topography and hard foundations are available in this soil.
3. Canal irrigation is generally preferred in __________
a) alluvial canal
b) non-alluvial canal
c) non-perennial canal
d) feeder canal
Answer: a
Clarification: Direct irrigation using a weir or barrage (canal irrigation) is generally preferred in alluvial soil as compared to storage irrigation. Alluvial soil is a fine-grained fertile soil and due to its porosity and texture provides good drainage making it highly productive and suitable for agriculture.
4. Which of the following combination is not correct?
a) Feeder canal – no direct irrigation is carried out
b) Protective canal – constructed as a relief work during the famine
c) Lined canal – provided with a lining of impervious material on its bed
d) Contour canal – provision of cross drainage works is not required
Answer: d
Clarification: A feeder canal is used to feed another canal and no direct irrigation is carried out from it. A protective canal is constructed to provide employment in the famine-affected area. A lined canal is provided with a lining of impervious material to prevent the seepage of water. A contour canal has to cross the drainage and hence, cross drainage works are required.
5. Which canal is not provided with any headworks for diversion of river water?
a) Permanent canal
b) Feeder canal
c) Perennial canals
d) Inundation canals
Answer: d
Clarification: An inundation canal is a canal which gets its supplies only when the water level in the river from which it takes off rises during floods. They obtain their supplies through open cuts in the banks of the river.
6. The velocity of the flowing water in a navigation canal should be __________
a) high
b) very high
c) small
d) medium
Answer: c
Clarification: A navigation canal is constructed to provide various navigation facilities. The velocity of flowing water should be small for easy movement of small ships and barges in the direction of flow of water as well as in the opposite direction.
7. Which one is well traded and is provided with permanent regulation and distribution works?
a) Inundation canals
b) Permanent canals
c) Alluvial canal
d) Navigation canals
Answer: b
Clarification: A permanent canal is the one that is fed by a permanent source of supply. The provision of permanent regulation and distribution works is made in the permanent canal. It is further classified as Perennial canals and non-perennial canals.
8. Which canal acts as an irrigation canal as well as a feeder canal?
a) Feeder canal
b) Carrier canal
c) Inundation canal
d) Permanent canal
Answer: b
Clarification: A carrier canal is a canal used for both direct irrigation and for feeding water to another canal. Thus, it acts as an irrigation canal as well as a feeder canal. Upper Chenab Canal is an example of this type of canal.
9. Hard foundations are generally available in non-alluvial soils.
a) True
b) False
Answer: a
Clarification: Non-alluvial soils are formed by the disintegration of mountainous rocks. Due to its uneven topography and rocky mass formed after disintegration, hard foundations are generally available.
10. A canal which when fully developed yields enough revenue to cover up its running cost is known as _____________
a) protective canal
b) productive canal
c) permanent canal
d) inundation canal
Answer: b
Clarification: After the development of the canal system the revenue obtained from the cultivators is such that it is more than the maintenance expenditure. This exceeding amount of revenue is so adjusted that it is about 2% of the cost of the canal system. With this rate, the total cost of the project will be recovered in about 50 years.