The quantum of water scarcity is best evaluated when we witness the beeline of tankers in most apartments in the city. If there is a panacea feasible for such realistic problems, it is in the generation of a water bank for sustainability in community living.
This is exactly what experts at BCIL say, as their projects focus on localised energy generation, and several of their projects have won awards for bringing in water solutions that reduce/eliminate dependence on water supply from State infrastructure.
Chandrashekar Hariharan, CEO & Co-founder of BCIL, says, “A typical RWH system to be installed in an average 1000 sq. ft. house will cost anywhere from Rs. 10,000 to Rs. 25,000 depending on the kind of set-up raised. The investment will pay back in less than five years in financial terms while offering priceless water security for the long term.” The green builder indicates that the cost is higher if the storage tank capacity you create is higher.
“RWH depends critically on the quantum of storage you need. Remember that we receive all our rains in 87 to 90 hrs, or about 1 per cent of the entire time in a year. Our kings and society-conscious planners of yore chose to create the intricate network of tanks and lakebeds for this reason alone. If we don't plan groundwater recharge, open wells, and storage capacities in as many places as we can, including our own homes and apartments, we can't expect magical solutions to emerge,” he warns.
Three imperatives
Hariharan suggests three essentials for water saving:
* Spend Rs. 2,000 in your house and fit aerators for every tap and shower to see that the flow rate is reduced to under seven litres per minute for taps and 12 litres per minute for showers, without any compromise on comfort or convenience. You will save 35,000 litres a year for a household of four people. For 500,000 households in the city, this means about 20 billion litres a year saved. You will save about 15 to 20 per cent of fresh water demand in a year. That will bring relief to your own BWSSB that is only a service provider.
* Spend about Rs. 10,000-15,000 for a RWH structure in your house particularly in apartment blocks, and you will save up to about 250,000 litres a household. Remember that you need no more than 365,000 litres to run your house. If some part of the RWH water is used for recharging the borewell in apartments, the rest will serve your need for car wash and such other applications. You will reduce fresh water demand by at least 10 per cent in a year. This will bring relief to BWSSB in its role as a service provider.
* If you took away the use of fresh water for your flush tanks and your gardens by spending Rs. 15,000 per household in any apartment that hosts more than 25 homes, you will have reduced your fresh water demand by 400 litres a day in your house. That is about 40 per cent of your daily water use!
“You can clearly see the impact on city's demand for water that will come about if all households did just these three things,” reiterates Hariharan. “And they don't cost too much. The benefit of such an investment and savings are yours. And in increasing your self-reliance, you will have eased a bit of the onerous task insisted so much from the BWSSB.”
