Harvesting rooftop rainwater is one answer to the city’s
WHAT is rooftop rainwater harvesting?
The process of collecting, storing and using rain falling
on rooftops of houses or other constructions is called,
rooftop rainwater harvesting.
WHY harvest rainwater?
Because rainwater is a pure natural resource and saving
it makes ecological and financial sense.
WHO can harvest rooftop rainwater?
Rainwater harvesting is for any person
planning to build a house or who is in the process
of building a house on an independent plot in Bangalore.
Persons with already built houses can also
harvest rainwater by ‘retrofitting’
such a built house for rainwater harvesting.
Persons in apartments can also harvest
rainwater but a community approach may be required
in such a case.
Industries and factories
can harvest rainwater since large roof areas are
usually available in such constructions.
People who are purchasing water from
private water tankers can harvest rainwater to lessen
their financial outflow.
WHEN to harvest rooftop rainwater?
It is possible to collect rainwater in Bangalore throughout
the year and use the same for gardening, car washing,
washing clothes, dishes, bathing, toilet, house swabbing
and other domestic non-potable purposes. If you want
to use the harvested rainwater for all purposes including
drinking and cooking, it is a must to boil and filter
DESIGN your roof well for rainwater collection.
A flat roof can be gently sloped to drain water
towards the storage system. A ‘nahani trap’ or ‘floor
trap can be placed at the time of casting the roof
just near the inlets of the down water pipes.
Sloping roofs should have a gutter of PVC or Zinc
sheet to collect water and channel it to the down
water pipe system.
Roofs should be uncluttered and should be easy to
clean by sweeping and swabbing if necessary.
Down water pipes should be designed well - 90 mm
diameter. PVC pipes resistant to UV rays appear to
be the best bet as down water pipes. Of course this
depends on the roof area to be drained.
3 to 4 down water pipes seem enough for a 1,000
to 1,200 square feet area.
Filter the rainwater before storage: filtering
can be as basic as a floor trap placed before the
water enters the down water pipe or a piece of sponge
placed at the inlet of the down water pipe. A PVC
bucket with gravel, sand and charcoal is a good filter
before rain water is stored. A PVC drum with sponge
on the inlet and outlet is also a filter. A small
two chamber inspection filter tank can also be devised.
DESIGN tips for rainwater harvesting.
Try to determine your storage system at the planning
stage itself. Would it be a:
roof level storage tank
a ground level drum or masonry tank
a below the ground sump
a partially below ground and partially above ground
Locate the storage system appropriately.
Roof level storage tanks may need to be at the rear of
the house or on the sides so that it is neither obstrusive
or visually offensive.
Ground level drums or tanks occupy space and should not
hinder movement or appear unsightly.
Below the ground sump is a good option since most new
constructions in Bangalore go in for sumps anyway. Sumps
are hidden from view, less costly to build and do not
Note: Always provide for an outlet for excess collection
of water from the storage system.
Further treatment of stored rainwater
It is a common perception that water stored for long goes
bad. If water does not contain any organic material and
if it is stored in a clean container it can stay for very
Some small treatment like ‘alum dosing’ or ‘chlorination’
can also be done to stored water to improve its quality.
Addition of a small quantity of alum dissolved in half
a bucket of water will bring down the suspended solids
and clear the stored rainwater.
Similarly adding a small quantity of bleaching powder
to half a bucket of water and then mixing it with the
stored rainwater will kill bacterial contamination.
Great care should be exercised while chlorinating and
it is not particularly recommended.
It is always recommended that water used for drinking
should be boiled and filtered invariably.
Courtesy: Environment and Health Foundation (India).
The foundation, considering the severity of water scarcity
in Bangalore had conducted a seminar on ‘rain water harvesting
for Bangalore’ on November 11th, 1999, in the city.
For more tips on rain water harvesting contact EHF (India)
at: Address: # 7, 8th Main Road, 3rd Phase,
2nd Stage, Domlur, Bangalore 560 071 Phone: 530 8137, 554 3397
web site: www.inika.com/chitra
to make life easier
Do you feel that there are simply not enough hours in
a day to accomplish everything? Do you wonder where you'll
find energy to go to work, fix the meals, maintain your
house, manage your money, educate your children, etc.
In short, do you wish to make your life less difficult?
Here we present some practical solutions for everyday
your carpet smelling fresh and clean with baking soda
- just sprinkle the soda liberally over the entire carpet
and let it sit for an hour. Then vacuum it up.
a sweeter smelling house, squeeze a few drops of lemon
juice into the dust-bag of your vacuum cleaner before
you start it up.
can use mayonnaise to remove crayon marks from wood furniture.
Just let it sit for ten minutes and then rub with a soft
is an inexpensive and effective cleaning agent and it
has many practical uses:
remove white water deposits from your pots and pans, simply
pour white vinegar into the pot and boil for 15 minutes.
your dishwasher is child's play if you run an empty cycle
with white vinegar.
White vinegar can also remove stains and odours of pets
from the carpet.
When you are painting, just add a few drops of vanilla
essence to the paint when mixing. This will remove the
unpleasant smell and still won't affect the colour.
keep the toilet bowl sparkling, mix equal parts of baking
soda and borax; add white vinegar and use this mixture
as a cleaning fluid.
Avoid long, uninterrupted use of your blender. Such
misuse can overheat the motor and possibly cause a breakdown.
the mixing bowl from slipping on the countertop when
using a handheld mixer by putting a rubberised mat or
a damp cloth underneath it.
a piece of plastic wrap over the top of your processor's
bowl before you put on the lid. After processing, you'll
discover that the usually splatter-splashed lid is spotless.
offensive odours from your microwave by placing a thick
slice of lemon on a paper towel and microwaving it on
high for about a minute and a half.
To avoid browning of apples after cutting, apply a little
lemon juice on the cut surface. The apples will stay
and look fresh for a longer time.
boiling milk, always add a little water in the vessel
to avoid milk from sticking to the bottom.
You can also leave a spoon in the vessel in which the
milk is being boiled at low heat so that it does not get
burnt at the bottom.
Keep coriander leaves in a muslin cloth bag, in the
refrigerator. They will remain fresh for a longer time.
Add a tablespoon of hot oil to homemade pastes of garlic,
ginger or green chilli, along with salt to make it
last longer and taste fresher.
the stems of green chillies while storing them.This
will help them stay fresh for long.
raisins in an airtight container in the refrigerator.
They will stay fresh for much longer.
using ginger and garlic paste in curries, always use
garlic at 60% ratio and ginger at 40% as ginger is very
strong and will make your dish sharp and pungent.
To remove bad breath chew Eliachi (green cardamom)
/ Sanuf (aniseed) / Laung (Cloves).
a piece of Laung (clove) after a meal helps in
seven almonds in water overnight, remove the skin and
boil it with a glass of milk and sugar and drink it.
Repeat this for 20 - 25 days. It helps enhance memory.
or two drops of eucalyptus oil on a handkerchief works
as a good inhaler if one has a running nose.
A few drops of eucalyptus oil, when added to hot water,
provides relief during cold, when inhaled.
mixture of ginger juice and honey (warmed), if taken
before going to bed brings great relief to severe cough.
mixture of cardamom seeds, a pinch of black salt and
a few drops of lemon, taken with luke warm water, provides
relief during a stomach ache.
flake of garlic, swallowed with water, on an empty stomach
everyday in the morning can be helpful in providing
relief during stomach and gastric problems.
a clove provides relief in toothache.
To remove an ink-stain apply toothpaste on both sides
of the ink-stain. Wash after it dries.
a candle to last longer, place it in a bowl of water.
A mixture of milk and spirit can be helpful in removing
ball pen marks from foam leather.
When storing woollen clothes, place dried neem (margo)
leaves in them to avoid worms and insects.
To get rid of dandruff, apply a mixture of lemon and
coconut oil on your scalp for at least 2 hours
(twice a week).
Do not throw away orange peels. Dry and
powder it. Add milk or rose water to make a fine
paste. Apply on your face for a fresh and glowing
not throw away an old tooth brush, as it can be used
for cleaning jewellery, bottles and metals.
all your silverware with toothpaste. They will sparkle
like they were bought yesterday.
To remove grease stains from clothes, sprinkle some
talcum powder over the grease as soon as possible. Keep
aside for a while & wash with soap and water as
Used tea leaves are good manure for plants.
Oil stains may be removed by rubbing with a piece of
lemon dipped in salt. Later wash off with soap.