Rainwater expert shows the way for conservation
When Bangalore Water Supply & Sewerage Board’s (BWSSB) plea to save water fell on deaf ears of citizens, City-based water expert showed the way on how a house can ensure self reliability using simple methods of water harvesting, judicious use and reuse.
BWSSB earlier this year had advocated water conservation. But their plea went in vain. While the people and BWSSB are pondering over where to get water from, Vishwanath’s house in Vidyaranyapura has a surplus of water. “A family of four on an average requires one lakh litres of water annually, which can be obtained through rain water harvesting,” Vishwanath told Deccan Herald. What makes this house unique is it does not have BWSSB connection and thrives entirely on water harvesting and conservation.
The waste water used for washing and bathing (grey water) is reused by treating it using a simple technology by passing through ‘cat-tails’ and ‘pipyrous,’ commonly available water reeds. The waste water collected in a tank is passed through these reeds grown in ferro cement tanks atop the terrace.
It is passed through a sand bed for purification and part of it is used to flush the toilet and the remaining used for gardening and recharging the ground water.
The black water (waste water from kitchen) is collected and stored in a tank and subjected to oil and grease trap before subjecting to sand filter and using it for gardening. “On an average a family of four members requires 300 litres of water which will be 9,000 litres every month. An efficient washing machine requires 40 litres of water if fully loaded. What we reuse will make a huge difference in water conservation,” explains Vishwanath. Vishwanath’s terrace has fruits, vegetables and flower plants which have been grown using waste water. He even cultivates indigenous variety of paddy on his terrace. The family is entirely dependent on rainwater for drinking and cooking, which is collected and filtered.
A recharge pit outside the house — two feet in diameter and 12-metre deep recharges upto one million litre of water. However, the water level here is depleting as there are more users in the neighbourhood.
“I am the only person who is recharging, if others join me, water level will increase substantially,” he said. The waterless toilet reduces dependency on water. The faecal matter and urine is collected separately into a bin and sent to compost bin, where it is converted into manure and used as nutrition to plants.