Which of the following factor causing waterlogging suggests extensive irrigation?

Civil Engineering : Irrigation - Quiz(MCQ)

Excessive Rains

Over and Intensive Irrigation

Impervious Obstruction

Seepage of Water from High Lands

Correct Answer : Over and Intensive Irrigation

Explanation : When intensive irrigation is practiced, it only irrigates a small portion of the whole irrigable land. Due to this over irrigation it leads to heavy percolation which leads to rising of water table causing waterlogging. So, to prevent waterlogging extensive method of irrigation is recommended.

Recently Updated in Irrigation Questions

Which type of lining is mixed and placed under temperature?

Dry Stone Lining

Shotcrete Lining

Cement Concrete Lining

Asphaltic Concrete Lining

Correct Answer : Option (D) : Asphaltic Concrete Lining

Explanation : Asphaltic concrete lining has been under evolution. It is used in very few places. This concrete is a careful mixture of asphalt and graded stone aggregate, and is mixed and applied under elevated temperature. This is a flexible lining and readily confirms to subgrade.

Calculate hydraulic mean depth for concrete-lined channel to carry a discharge of 350 cumecs at a slope of 1 in 5000. The value of manning’s constant for the lining is 0.015. The side slopes of a channel may be taken as 1.5:1. Assume limiting velocity in the channel as 2m/sec.

2.20 m

2.40 m

2.60 m

2.80 m

Correct Answer : Option (D) : 2.80 m

Explaination : Using Manning’s equation: V = 1/n.R2/3.S½
2 = 1/0.015 x Râ…” x 1/5000½
R = 2.80 m.

What is the maximum permissible velocity in Cement concrete lining (Unreinforced) as per Indian Standards?

1.2 to 1.8 m/sec

2 to 2.5 m/sec

1.5 to 2 m/sec

1.5 to 2.5 m/sec

Correct Answer : Option (B) : 2 to 2.5 m/sec

Explanation : The maximum permissible velocity for unreinforced cement concrete lining is 2.0 to 2.5 m/sec. For Boulder lining, the maximum permissible velocity is 1.5 m/sec.