Canal Alignment and Earthwork MCQ with answer and solution

Concept

Canal alignment along natural drainage

Formula

NONE

Step-by-step solution

1. A side slope canal is aligned roughly perpendicular to ground contours and parallel to natural drainage lines. 2. A contour canal runs nearly parallel to contour lines, while a watershed canal runs along the ridge line. 3. Hence, the canal aligned approximately parallel to natural drainage is a side slope canal. Answer: A

Explanation

A side slope canal is constructed along the natural slope of the land, running perpendicular to contour lines. Because it runs parallel to natural drainage lines, it does not intercept surface runoff and requires minimal cross-drainage works. Therefore, a canal aligned parallel to natural drainage is a side slope canal.

Why the other options are wrong

B) Contour canal is aligned nearly parallel to contour lines, perpendicular to natural drainage. C) Watershed canal is aligned along the ridge line or watershed. D) Ridge canal is another name for a watershed canal.

Shortcut

Side slope canals run perpendicular to contours, making them parallel to natural drainage.

Common mistake

Confusing side slope canals with contour canals, which run nearly parallel to contours rather than natural drainage.