Question

Our country has a long history of water conservation techniques like (i) Surangam (Kerela): A horizontal well dug in laterite rock until a significant amount of water is struck. This water seeps out of the hard rock. Outside of the Surangam, the water is gathered in an open pit. (ii) Bawaris/Baolis (Rajasthan): A system of layered steps was created around the reservoirs to narrow and deepen the wells, reducing water loss through evaporation harvesting the scanty rainfall received by the region. (iii) Eri/Ooranis (Tamil Nadu): A tank system that manages floods, minimises soil erosion and runoff during heavy rains. Thus recharging groundwater. (iv) Ahar Pynes (Bihar) are reservoirs with three-sided embankments (Ahar) constructed at the end of man-made diversion channels (Pynes). (v) Zing (Ladakh): Tank used to harvest water from glaciers. As the glacier melts during the day, a network of channels fill up with water. By the afternoon the water in the channels turns into a flowing stream which collects in the tank by evening and is used the next day.

Which one would be suitable for your city? Have you observed any of these traditional systems? If you have, briefly describe it.

Answer 1

For an urban city, the most suitable traditional water conservation system would be rooftop rainwater harvesting combined with tanks or reservoirs like Baolis (step wells), which reduce evaporation and collect rainwater efficiently. Baolis are particularly suitable because they can be integrated into urban spaces to collect and store rainwater, mitigating water scarcity.

I have observed Baolis (step wells) in historical sites. These are stepped systems around wells or reservoirs that efficiently store and conserve water by reducing evaporation and making water access easier through steps.

Rooftop rainwater harvesting, a modern adaptation derived from these traditional methods, is commonly practiced in many cities today to recharge groundwater, reduce flooding and manage water demand.

Thus, Baolis or rooftop rainwater harvesting systems adapted from traditional techniques like Surangam or Baolis would be appropriate for city water conservation needs.