What is the nightmare for designers as a house nears completion? One answer is overhead water tanks! If they happened to be visible from the road, no design seems to be convincing enough. Possibly so, most house owners do not bother about how it appears, leaving it as a sore thumb rising from a beautifully designed house.
Besides the matter of aesthetics, the very idea of high-level water tanks is an energy consuming proposal. The electricity required to pump water from low levels to cities at higher plateau, then take it from ground level treatment plants to large neighbourhood water tanks demands a good share of the city electricity supply. Though the supply to individual sites is on gravity flow, imagine each building again pumping it up – the whole exercise appears to be against the natural principles of water flow. Though the story of reaching water from a far-off river to the house kitchen is exciting as a civilisation achievement, it is also a story of battling against nature, consuming resources.
Many cities around the world are not dotted with water tanks forming their skylines, yet get day long water supply. From the treatment plants or a nearby surface level water sump, water is pumped continuously such that the houses need neither underground sump nor overhead tank. Just turn the tap on to get water anytime. It has been studied that such an arrangement does not necessarily increase water consumption, makes the pipes last longer avoiding the dry and wet conditions, avoids duplicating storage at every level keeping the final supply fresh, and saves lot of money otherwise spent by individual families. Above all, it negates the illogic of pumping water up the sky twice, against gravity.
Direct pumping is possible at the house level also with pumps connected from the sump to outlets. Whenever we turn a tap on, the pump automatically starts pumping water and stops when we close the tap. This measure avoids the need for an overhead tank and reduces the overall running length of pipes, offering monetary savings. Of course there should be regular power to ensure pumping at any time.
Inadequacy of supply
The present approach of having tall and large water tanks supplying water for a few hours to a large area means inadequacy of supply by gravity flow, pumping as a necessity, provision for sump with tank and longer lengths of pipes with pressure loss. One alternative lies in smaller water tanks spread over smaller areas to ensure full day water flow by gravity such that no house needs to build either a sump or a tank. When we feel the scarcity of water we tend to store it, only to use it later carelessly, but an assurance of regular supply automatically regulates the consumption as well. There is no proof to claim that longer supply means greater consumption, for everyday we all need water only for specific purposes, hence only in specific quantities.