Question

The permanent irrigation channels should not usually have side slopes steeper than

• A. \(\frac{1}{2}\) to \(1\)
• B. \(1\frac{1}{2}\) to \(1\)
• C. \(2\) to \(1\)
• D. \(3\) to \(1\)

Hint:

Permanent irrigation channels require stable side slopes to prevent bank failure and erosion.

Answer 1

The Correct Option is B

Concept:
Side slope of an irrigation channel is selected according to soil type, stability, and erosion resistance.

Step 1: A steeper side slope may become unstable and collapse.

Step 2: Permanent irrigation channels should have stable side slopes for long-term use.

Step 3: If the side slope is too steep, erosion and bank failure may occur.

Step 4: Therefore, permanent irrigation channels should not usually have side slopes steeper than: \[ 1\frac{1}{2}:1 \]

Step 5: Hence, the correct answer is \(1\frac{1}{2}\) to \(1\). \[ \boxed{1\frac{1}{2}\text{ to }1} \]