Question

Percolation tank is constructed to impound
A) Runoff water
B) Water vapour
C) Purified water
D) None of the above

Answer 1

Hint: Percolation tank has a structure to impound rainwater that flows into a watershed. It helps in recharging groundwater.

Complete answer:
To answer this question, first, we need to know about the percolation tank. Percolation tank is an artificial reservoir constructed across shore, submerging a sufficiently permeable land area to encourage sufficient percolation to absorb surface water run-off and allow it to percolate within the permeable ground. This is one of the successful groundwater table refilling methods. Percolation tanks are located in abundance in States such as Tamil Nadu, Maharashtra, Andhra Pradesh, Gujarat, and Karnataka.
Now lets us find the solution from the given options-
Percolation tanks are the structures for groundwater recharge. These are usually constructed across streams and larger riverbeds to impound a portion of run-off water. It is a surface water body artificially formed, submerging a highly permeable land in its reservoir so that the surface runoff is allowed to percolate and recharge the groundwater storage. This water makes its way into the subsoil in due course and recharges the water there. That contributes to better well recovery in downstream areas. So, water vapour and purified water is not the main objective of percolation water to impound.

Thus, the right answer is option A i.e., Runoff water

Note: Percolation tank is made for recharging groundwater. It is not impounded to purified water because the purified water tank requires many devices and pipes to purify the water.