
Residents of the Ban Mae Nam community living on Soi Engsae Mae Nam Shrine in Moo 1 village in Tambon Mae Nam on the island said the black water of a ditch emptied into the sea without being treated.
The black water turned the sand and part of the beach into black and it has foul smell, prompting tourists to stay away from the beach.
The local residents said they have complained to the Samui municipality but no action has been taken.