CHAPTER 4
WATERSHED RECHARGE
EXERCISE
QUESTION FOR WRITTEN WORK
Answer the following question in brief:
(1) What is groundwater recharge?
Ans.
i) Groundwater recharge is the process of infiltrating rainwater into the soil
in various ways to increase groundwater storage.
ii) Proper precautions are to be taken to keep groundwater free from any
type of contamination.
(2) Explain in brief the need for water recharge.
Ans.
i) Water is required for drinking , agriculture, industries and many
other purposes. Groundwater level is declining day by day.
ii) At many places groundwater is overused or misused.
Therefore, it is also necessary to use the available groundwater
sparingly and scientifically.
(3) Why is it necessary to recharge borewells?
Ans.
i) Recharging is most advisable to dry and drying up well with
reducing yield , even a running borewell can have recharging
in case of surplus surface water which otherwise goes to
drains.
ii) With groundwater level going down rapidly, there is an
urgent need to revive them.
(4) Why should groundwater be recharged in cities?
Ans.
Sewers leak, as shown by the main examples of
groundwater pollution below cities sewage, many urban
areas do not sewer relying on septic tanks and soakways
to dispose of effluents-this water must recharge
groundwater.
(5)Write the names of filtration devices used for filtration of
roof rainwater?
Ans.
i) Sand filter
ii) Coal filter
iii) Filter in pipes
(6) Explain the importance of suction pits in the process of water
recharge.
Ans.
i) To recharge rainwater in the surrounding areas of sources like well or
bore well, a suction water, pit acts as a filter.
ii)To absorb-rainwater water, a pit is a dug at a particular level in which
the rainwater is to be recharged. An important part of the rain water
filtration system is the suction.
(7) Groundwater should be used sparingly. Explain this
statement.
Ans.
i) We need to save water for various purposes.
ii)In some areas ground water is the only source of water.
iii)At many places groundwater is overused or misused.
Therefore ground water should be used sparingly.
(8) What are the methods of water conservation?
Ans.
i) Ground water recharge-process of infiltration rainwater into the
soil.
ii) Filtration system-filtration of rainwater is highly essential
before groundwater recharge.
iii)Rainwater recharge-roof rainwater in various ways.
(9) What care should be taken while recharging a well
or borewell?
Ans.
i) Water coming to the stream should be free from salts
and chemicals.
ii) Water should be the pipe to the bottom of the well.
iii) Recharge should be done with filtered and clean
water only.
(10) Explain with reason the most useful method of water
filtration in your area .
Ans.
i) The section pit is the most useful method of water filtration in
our area. In our area there are less roof top houses. Hence, filters
for the roof area are not sufficient.
ii) Suction pits are used in surrounding areas of wells and
borewells. In our areas houses have bore wells. Therefore, suction
pits are the most useful method for us.