The girl, Satya Sapkota, was on her way home from school after heavy monsoon rain flooded roads in Samakhusi, Kathmandu.
While trying to cross the road, she failed to noticed the open drain and fell into it.
Women, who filmed the incident, can be heard screaming as the girl disappeared underwater before people could run to help.
However, the girl miraculously resurfaced down the street seconds later having been spit out into the open. The teenager was then rescued and pulled out from the water by people.