Flood Control Structures MCQ with answer and solution

Concept

ach flood control work has a special role: check dams slow stream flow, terrace bunds hold soil and water on farms, and levees protect land beside rivers.

Step-by-step solution

1. Check dams are small barriers built across small streams and gullies. They reduce the runoff velocity in stream channels. So A-2. 2. Terrace bunds are earth embankments made along contours on farm land. They arrest sediment and surface runoff in agricultural lands. So B-3. 3. Levees are earth embankments built along river banks. They protect the surrounding areas of the river from floods. So C-1. 4. The correct match is A-2, B-3, C-1, which is option (C).

Explanation

Check dams are built across small stream channels to slow down the flow, which reduces erosion and peak flow. Terrace bunds are made on farm land to stop soil and water from flowing away. Levees are long embankments along a river that keep flood water inside the river and protect nearby land.

Why the other options are wrong

Option A is wrong because it matches check dams with flood protection and levees with sediment control. Option B is wrong because check dams do not protect areas beside rivers, and levees do not reduce velocity in stream channels. Option D is wrong because terrace bunds are on farm land, not along rivers, and levees do not arrest sediment on farms.

Shortcut

Levee = river bank protection (1), Check dam = stream velocity (2), Terrace bund = farm land soil (3).

Common mistake

Students mix up check dams and terrace bunds. Remember that check dams are in stream channels, while terrace bunds are on farm land.