The incident occurred at around 9 am when the four had gone to wash clothes in the canal in Nadigudem Mandal, a senior police official told PTI.
One of the girls, aged 19, accidentally fell into the water and in an attempt to rescue her, the other three, aged 10-14 years, entered the water, but all four of them drowned, she added.
"All the four bodies have been retrieved. The deceased are from Andhra Pradesh," the police official said.