RAS question
Inland drainage covers approximately what percentage of Rajasthan?
Correct answer: (D) 60%.
Internal drainage occurs across approximately 60% of Rajasthan.
Explanation
Internal drainage means that rivers do not ultimately reach the sea. Rajasthan's drainage system is divided into three parts, and internal drainage accounts for approximately 60%. Many streams flow only for a short distance before disappearing in dry plains or desert sands, or ending in salt lakes. Kantli, Banganga, Sabi or Sahibi, Ruparel, Rupangarh, Mentha, Kakni and Kachari are identified as important rivers of this kind. Internal drainage is therefore a major drainage pattern in the state, not an isolated local feature. Its approximate 60% share is associated with Rajasthan's arid terrain, low and uneven rainfall, and rivers that flow for short distances before ending within the state.
Why the other options are wrong
- (A) 10% is too low because internal drainage occurs across approximately 60% of Rajasthan.
- (B) 20% also understates the extent of internal drainage, which occurs across approximately 60% of Rajasthan.
- (C) 30% is only half of the expected approximate share; internal drainage occurs across approximately 60% of Rajasthan.
Concept
This tests Rajasthan's drainage systems, especially the distinction between internal drainage and river systems that ultimately drain towards the sea. It recurs in RAS because questions connect aridity, rainfall, salt lakes, river direction, and short seasonal rivers that disappear in desert terrain.