Rainwater harvesting is the technique to capture the rainwater where it
falls on the earth surface before it drains away as surface run-off. The
rainwater harvesting system helps to replenish groundwater aquifers, prevent
soil erosion by storm water, reduce reliance on dams and canals, control floods
in neighborhood and use rainwater for irrigation and domestic purposes.
The Indian government aims to provide clean drinking water to every household
by 2024 but with increasing water scarcity around the globe, how we can achieve
this goal? India is a rain-fed country where the main source of freshwater is
the rainfall during the Monsoon season. Most of the rainwater is not utilized
judiciously and is allowed to drain away as surface run-offs causing
floods in Monsoon and water scarcity in other seasons. So the need of the hour
is to capture this surface run-off water and put it to use and one way of doing
this is RAINWATER HARVESTING.
Availability of Freshwater
The freshwater forms only 3% of the total water present on the earth and out of which 2% is trapped in glaciers and icecaps. Hence, only 1% of total freshwater is available for human consumption which is found in rivers, lakes, swamps, ponds and groundwater.
The surface run-off water percolates down the soil and recharges
groundwater aquifers. As the groundwater level increases, the water oozes out
the surface as springs like perennial rivers, lakes and streams.
What are the reasons of Water Crisis ?
The main reason of water crisis is the availability of water in
wrong place, at wrong time and in wrong quantity. Thus, availability
of freshwater is affected by the increasing population along with rapid
urbanization and industrialization.
1) Population:
With increasing population, water demand has increased and it has
surpassed the capacity of nature to recharge the water resources.
2) Urbanization:
Rapid urbanization has resulted in concretization which prevents water
to percolate down the soil and surface run-off causes soil erosion and
flooding.
3) Industrialization:
Industrialization has deteriorated the water quality due to discharge of
pollutants and made water unfit for human consumption.
How to meet ever increasing demand of water in a sustainable manner?
The increase in population, urbanization and industrialization has
resulted in water scarcity and environment deterioration. It is important to
meet the increasing demand for water in a sustainable manner so that water
resources are available for the future generations.
The identification of new freshwater sources requires huge capital
investments. Thus, the best way to handle the increasing demand for water is to
not exploit the existing freshwater sources by overuse and rationally managing
and augmenting the existing water resources by capturing the surface run-off
water and putting it to use.
How to store surface run-off water?
1) Construct large reservoirs and dams
- Requires huge capital
investments
2) Capture rainwater at its source by rainwater harvesting techniques
What is Rainwater Harvesting?
Rainwater harvesting is a technique to collect rain water where it falls
on the earth surface before it drains away as surface run-off. The rainwater
harvesting helps to replenish groundwater aquifers, prevent soil erosion by
storm water, reduce reliance on dams and canals, control floods in
neighborhood and use rainwater for irrigation and domestic purposes.
The collection and storage of rainwater for future use can be done both
at the individual and community level.
a) Individual level:
At household level, the rainwater harvesting can be done through roof
catchments.
b) Community level:
At community level, the rainwater harvesting can be done through ground
catchments.
What are the components of Rainwater Harvesting system?
The three components of Rainwater Harvesting system are:
a) Catchment
b) Collection system
c) Utilization system
1) Catchment
Catchment is the surface area from where rainwater is collected before
it drains away as surface run-off.
A catchment area can be:
- Rooftop of a building or
household,
- Ground areas such as
pavement, lawns and lands with or without vegetation
2) Collection system
The rainwater from catchment area is collected and stored by collection
system of rainwater harvesting.
The collection system comprises of pipes and channels through
which runoff water is collected and a storage structure where
rainwater will be stored for future use.
3) Utilization system
The rainwater collected and stored in storage structures such as tanks
or natural depressions or pits in the ground, can be utilized through a
utilization system. The utilization system of rainwater harvesting directs the
stored water to the point of use.
The utilization system can consist of :
- hose pipes,
- drip irrigation
system,
- perforated pipes,
- channel pipes
Importance of Rainwater Harvesting system
1) Rainwater harvesting decreases reliance on water from dams,
reservoirs and canals.
2) Catching rainwater reduces flow of storm water, thereby reducing the
flooding of areas.
3) Rainwater harvesting prevents soil erosion caused by surface run-off
of storm water.
4) Captured rainwater provides high quality water which is low in
mineral content at relatively cheaper rates.
5) Rainwater harvesting reduces the siltation and contamination of
waterways by polluted surface run-offs.
6) Use rainwater for irrigation of landscapes.
7) Control flood by collecting run-off water through open channels and
diverting it to another area through gates and diverters.
8) Helps to conserve water in a sustainable manner.
Continue to read about:
Note:
********
If the article was helpful, don't forget to like, share or
comment on it. It will help us improve the quality of material.
No comments:
Post a Comment