Pasir Ris: mystery pipes discharging to the sea

Outside the Pasir Ris Park boundary, there are a series of long pipes leading out of the forested area, across the intertidal and into the sea.

What is going on with the pipes?


The pipes go across the intertidal.

And lead out to the sea.

Another view of the pipes.

There is another pipe that seems better supported leading out from the forest to the sea.

Do these pipes come from the businesses location behind the forested area that edges this shore?  A view of the area from Google Earth.

A view from Streetdirectory.com which suggests that the businesses there include fish farms.

Where exactly do these pipes come from? Are these pipes approved? What is being discharged through these pipes? If you know please leave a comment. Thank you!