Appearances . . .

. . . can be deceptive.  This is not an outflow of sewage (although there are such pipes not far from here) but the mud of the harbour nearby.  It's being dredged and the result piped along the bay, past the beach, to near some rocks.

There's a banner announcing the nature of the outflow, but I'd be willing to bet that someone has photographed it and described it otherwise.