Question

the fourth treatment stage know as aquifer recharge, involves either holding the water at a pool from which it seeps into the underlying aquifer, or directly injecting the water into the subsurface. which of the two methods can improve the quality of water, explain in short

Answer 1

*Holding the water at a pool from which it seeps in to the underlying aquifer is the better approach and improve water quality when compared to artificial recharge.

*Artificial subsurface groundwater recharge is a process to capture lost water due to runoff and evaporation in the areas where groundwater supplies are depleted. Long-term withdrawal exceeds long term recharge, which has led to the depletion of the groundwater level. In such regions it is required to recharge. When the impervious layers overlie deeper aquifers, the infiltration from surface cannot recharge the subsurface aquifer under natural conditions. The techniques adopted to recharge the confined aquifers directly from surface water source are grouped under subsurface recharge techniques.

**disadvantages with injecting.:

1.In adequate maintenance and repair may result in the contamination of aquifer.

2.Contamination of the groundwater due to water runoff from agricultural fields and road surfaces.

3.Treatment is required before subsurface recharge can be done to avoid contamination.