Just noticed it.Because the sewage line output is in wellawatta. Also all the open sewage from beach shanties are directly emptied to the beach
Sometimes, people from long distance come all the way to visit the dehiwela zoo and end up bathing in the beach. They have come a long way just to bath in shit
But people bathe in Mt Lavinia which is still very close.
I hear their "Ewww" when they get to know.