Question

Which of the following methods are employed for the estimation of infiltration characteristics of soil for design of irrigation system?

(A)	Use of Infiltrometer
(B)	Measurement of subsidence of free water in a large basin
(C)	Estimation of accumulated infiltration from water front advance data

Choose the correct answer from the options given below:

• A. (A), (B) and (C).
• B. (B) and (C) only.
• C. (A) and (C) only.
• D. (A), and (B) only.

Hint:

Consider whether each of the three techniques described actually measures water entering the soil over time.

Answer 1

The Correct Option is A

Step 1: Infiltration rate of soil is a key input for designing an irrigation system, and it is measured in the field by more than one standard method.

Step 2: The infiltrometer method, using a single or double ring pushed into the soil and recording the drop in ponded water level, is the most common direct method.

Step 3: The basin flooding method observes the subsidence of standing water depth in a large ponded basin over time, and the advance-recession method calculates accumulated infiltration from how far and how fast the water front moves along a furrow or border. All three, (A), (B) and (C), are recognized methods, so option 1 is correct.