Harvested rainwater is used
for direct usage or for recharging aquifers. It is most important to ensure
that the rainwater caught is free from pollutants. Following precautionary
measures should be taken while harvesting rainwater:-
1)
Roof
or terraces uses for harvesting should be clean, free from dust, algal plants
etc.
2)
Roof
should not be painted since most paints contain toxic substances and may peel
off.
3)
Do
not store chemicals, rusting iron, manure or detergent on the roof.
4)
Nesting
of birds on the roof should be prevented.
5)
Terraces
should not be used for toilets either by human beings or by pets.
6)
Provide
gratings at mouth of each drainpipe on terraces to trap leaves debris and
floating materials.
7)
Provision
of first rain separator should be made to flush off first rains.
8)
Do
not use polluted water to recharge ground water.
9)
Ground
water should only be recharged by rainwater.
10)
Before
recharging, suitable arrangements of filtering should be provided.
11)
Filter
media should be cleaned before every monsoon season.
12)
During
rainy season, the whole system (roof catchment, pipes, screens, first flush,
filters, and tanks) should be checked before and after each rain and preferably
cleaned after every dry period exceeding a month.
13)
At
the end of the dry season and just before the first shower of rain is
anticipated, the storage tank should be scrubbed and flushed off all sediments
and debris.