Page 18 - Water Every Drop Counts

GROUNDWATER : DIGGING DEEP

Groundwater makes up about 20% of the world’s
fresh water supply, almost equal to the total
amount of freshwater stored in the snow and ice
packs. Groundwater acts as a natural storage
that can buffer against temporary shortages of
surface water, as in the times of drought.

Just as river waters have been over-used and
polluted in many parts of the world, so too have
underground aquifers. The big difference is that
unlike rivers, aquifers are out of sight.

Inadequacies and inefficiencies of surface
irrigation schemes and changes in cropping
patterns often leads to increased dependence
on ground water. Increase in groundwater
withdrawals can lead to falling water table.

This is incidentally the scenario in most parts of
India. In certain areas, especially those dependent
on monsoons, the situation is alarming. Efforts to
regulate exploitation of groundwater resources
are being made at varous levels, but only with
limited success.

RAIN WATER HARVESTING

Rainwater harvesting is the process of collecting,
filtering and storing water falling as rain on roof
tops and other paved/ unpaved areas.

The harvested rainwater can be used for potable
purposes after testing and treatment, or used for
recharging ground water aquifers. Recharging
groundwater sources with rainwater can also
improve the quality of the groundwater (e.g.
lowering fluoride content). Rainwater harvesting
also means extracting that much less from
underground sources saving the energy needed
to pump out the same.

It has been said that if India can impound the
entire rainfall brought down up on its landmass
by the monsoons, it will be enough to submerge
its entire land area under 18 inches of water.

18