The roof top rainwater harvesting is the most common practice in Shillong inspite of the fact that Cherrapunjee and Mawsynram receiving the highest rainfall in the world are situated only at a distance of 55‌kms from there. Inspite of being very close to the area of highest rainfall in the world, Shillong faces acute shortage of water. Nearly every household in the city has a rooftop rainwater harvesting structure. Nearly 15−25% of the total water requirement of the household comes from rooftop water harvesting.