Sewage Treatment and Runoff in Cozumel

[jlyle]

Perhaps I should start another thread on cruise ships. I've asked, but never gotten an answer about what happens to the "gray water" from the boats. Gray water is the effluent from showers, sinks, etc. I suspect, but can't verify, that waste water is simply dumped while the boats are docked. This may the reason fish life north of the piers is declining.

I assume "black water" is forced into holding tanks and discharged when the boats are out at sea. God, I hope so.

Does anyone have any information or facts?

 

[Mark IV]

Perhaps I should start another thread on cruise ships. I've asked, but never gotten an answer about what happens to the "gray water" from the boats. Gray water is the effluent from showers, sinks, etc. I suspect, but can't verify, that waste water is simply dumped while the boats are docked. This may the reason fish life north of the piers is declining.

I assume "black water" is forced into holding tanks and discharged when the boats are out at sea. God, I hope so.

Does anyone have any information or facts?

I don't recall the mileage limits, but there are incremental limits where the ships can dump various levels of crap.
(I used to crew on a private yacht, that had a plaque in the galley that actually listed what can be dumped, and at what distances from shore).
Get far enough out into international waters, and they can dump almost anything they want, and they do. The cruise ships are some of the ocean's worst poluters. Walk down a secluded beach almost anywhere, and you'll find lots of plastic water bottles with the cruise ships logo on them (unless they've wised up in recent years, and no longer mark their bottles.)
I would think most solid trash was taken back to the home port, but you can almost be assured that they're pumping the holding tank out at sea.

 

[KeithG]

I don't recall the mileage limits, but there are incremental limits where the ships can dump various levels of crap.
(I used to crew on a private yacht, that had a plaque in the galley that actually listed what can be dumped, and at what distances from shore).
Get far enough out into international waters, and they can dump almost anything they want, and they do. The cruise ships are some of the ocean's worst poluters. Walk down a secluded beach almost anywhere, and you'll find lots of plastic water bottles with the cruise ships logo on them (unless they've wised up in recent years, and no longer mark their bottles.)
I would think most solid trash was taken back to the home port, but you can almost be assured that they're pumping the holding tank out at sea.

Depends upon the size of the boat. The following article is interesting
What happens when you flush the loo on a cruise ship?

I do know that the Caribbean LOBs we use do not have the ability to treat liquid wastes. They dump at sea (never the dock).

If you pay attention you will notice that sometimes the boat does a huge detour "out to sea" when moving to the next dive site.

Kitchen food waste is routinely dumped directly into the water as the boat casts off and moves to the next dive site (ever wondered why fish collect under the boat?).