Discuss how rainwater harvesting in semi-arid regions of Rajasthan is carried

In the semi-arid and arid regions of Rajasthan, particularly in Bikaner, Phalodi and Barmer, almost all the houses traditionally had underground tanks or tankas for storing drinking water. The tanks could be as large as a big room. One household in Phalodi had a tank that was 6.1 metres deep, 4.27 metres long and 2.44 metres wide. These tankas were part of the well developed rooftop rain water harvesting system. These were built inside the main house or the courtyard. They were connected to the sloping roofs of the houses through a pipe. Rain falling on the rooftops would travel down the pipe and was stored in these underground ‘tankos’. The first spell of rain was usually not collected as this would clean the roofs and the pipes. The rainwater from the subsequent showers was then collected. The rainwater is stored in the tankas till the next rainfall. It is the most reliable source of drinking water when all other sources are dried up, particularly in the summers. Rainwater called as ‘palar pani’ is considered the purest form of natural water. Not only this, many houses construct underground rooms adjoining the ‘tanka’ to beat the summer heat as it would keep the room cool. However, the practice of rooftop rainwater harvesting is on the decline due to the perennial Rajasthan Canal which has made the avaiiability of plenty of water in the area.