Canal Design and Regulation MCQ with answer and solution

Concept

Water logging happens when the water table rises into the root zone due to excess water input or poor drainage.

Step-by-step solution

1. Water logging means the root zone is saturated because the water table has risen. 2. Its causes include canal seepage, over-irrigation, inadequate drainage, excessive rain and submergence due to floods. 3. Adequate natural or surface drainage prevents water logging, so A and B are wrong. 4. Normal rains do not cause water logging, so C is wrong. 5. Submergence due to floods is a cause, so the answer is D.

Explanation

Water logging happens when too much water enters the land or drainage is poor. Long submergence due to floods saturates the soil and raises the water table. Good drainage and normal rains do not cause water logging.

Why the other options are wrong

A and B: Adequate drainage removes extra water, so it prevents water logging. C: Normal rains do not raise the water table enough; only excessive rains do.

Shortcut

Words like 'adequate' and 'normal' describe safe conditions. Pick the option showing excess water.

Common mistake

Thinking any rain causes water logging; only excessive rain does.