Sithi Nakha is a reminder for Kathmandu locals to keep water sources at home clean

Spot a house in Kathmandu with a rooftop or underground tank. Easy! Right? Now, spot someone cleaning them. Not so easy now! Right?

For Kathmanduites, either of the two kinds of tanks or both is a prerequisite. But, such tanks mushroomed only a couple of decades ago. If so, what about the time before that?