Water for Life 31
How to ensure safe water in a rainwater catchment tank
Collected rainwater must be kept free of contamination to be safe to drink. To
ensure that harvested rainwater will be safe:
• Clean the tank and entrance pipe before the rainy season.
• Allow the first rainfall to run through the catchment tank in order to clean it.
• Cover the tank and place a filter or screen over the inlets to keep out insects,
leaves, and dirt. This will help prevent mosquitoes from breeding.
• Make sure that water is taken out through taps only, and not by buckets or
other containers dipped into the tank.
• For added safety, add chlorine to the tank (see page 41) or connect a water
filter to the tank.
• Try not to stir or move the water so any dirt or germs in the tank will stay at
the bottom.
Community rainwater harvesting in Rajasthan
Communities in the Thar Desert of Rajasthan, India, have traditionally collected
rainwater in many ways. One way rainwater is collected is in village ponds, called
naadi. Everyone in the village, and even those passing by, may use naadi water.
In order to protect the water, everyone in the village works to maintain the naadi.
Ancient laws prohibit any trees from being cut near the edges of the naadi or in
the area where rainwater collects and runs into the naadi. Livestock are kept away
from the naadi, and people are not permitted to urinate or defecate near it. Once
a month, on the day of no moon, the entire village works to dig out sand and silt
that has collected in the naadi. Digging out the naadi makes it deeper and also
helps to remove germs that may have settled on the bottom. After digging it out,
the villagers allow the water to settle so it becomes clear again. In these ways, the
community comes together to protect the precious gift of water.