Question Bank • QB_SWCE_EXP_028 MCQ • 1 Mark

Section 4: Soil and Water Conservation Engineering

Hydrology

Subtopic: Runoff estimation

Question Statement:

In the SCS runoff curve number method, the standard initial abstraction $I_a$ is generally assumed to be:

Options:

  • (A) $I_a = 0.2 S$
  • (B) $I_a = 0.5 S$
  • (C) $I_a = 0.05 S$
  • (D) $I_a = 1.0 S$

Answer Key:

A

Step-by-Step Solution & Explanation

Empirical field analysis by the USDA Soil Conservation Service established the relation for initial abstraction as: $I_a = 0.2 S$ where $S$ is the potential maximum retention of the watershed.
← Previous (QB_SWCE_ADV_125) Next (QB_SWCE_008) →

Practice In Authentic CBT Exam Interface

Test your skills under authentic timed conditions with live scoring and AIR percentile ranking.

Launch CBT Mock Test