Question

The most commonly used lining material for canals in India is:

• A. cement concrete
• B. cement mortar
• C. low density polyethylene film
• D. bricks or tiles in sandwiched cement mortar

Hint:

Concrete is considered the gold standard for canal linings. It provides the best combination of hydraulic efficiency, weed suppression, durability, and low maintenance costs over the canal's lifespan.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Canal lining involves paving the bed and sides of an open canal with an impermeable material.
Lining is done to minimize seepage losses, prevent weed growth, reduce soil erosion, and increase the velocity of water flow, which improves the canal's overall hydraulic capacity.

Step 2: Detailed Explanation:
Let us compare the lining materials commonly used in India:
1. Cement Concrete (A):
Cement concrete lining is the most widely used and accepted lining material for major and medium irrigation canals in India.
It is highly durable, provides a smooth surface that maximizes water velocity, is highly resistant to weed growth and burrowing animals, and has a long service life ($40$ to $50\text{ years}$).
It can be cast in-situ or installed as precast concrete slabs, making it the standard lining material for modern irrigation projects.
Therefore, it is the most commonly used material.
2. Bricks or tiles in sandwiched cement mortar (D):
This method (using two layers of tiles with a layer of cement mortar in between) is also common in India, particularly in northern states like Punjab and Haryana, due to the cheap availability of clay.
However, it requires intensive manual labor and has more joints, making it more prone to leakage over time than concrete.
3. Low density polyethylene (LDPE) film (C):
LDPE films are used as buried membrane linings to prevent seepage, but they must be covered with a protective layer of soil or tiles to prevent physical damage from sunlight and animals.

Step 3: Final Answer:
The most commonly used and standard lining material for irrigation canals in India is cement concrete.
Hence, the correct option is (A).