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Waste discharge


basser
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No.

 

Food products may be chopped up and discharged, I believe. Any anything that can be burned can be discharged. But much waste is compacted and removed from the ship in port.

 

Thanks. I thought that was what I had heard.

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The answer is a big YES. Cruise ships dump over 1 billion gallons of waste each year into the ocean. This was back a year ago. Google it and you will find a large list of what they can dump a few miles off shore.

That’s according to Friends of the Earth, a non-governmental environmental group, which used US Environmental Protection Agency data to calculate arrive at that gross figure. The EPA estimates that single 3,000-person cruise ship pumps 150,000 gallons of sewage—about 10 backyard swimming pools’ worth—into the ocean per week. One vessel in an EPA study produced 74,000 gallons of sewage (pdf, p.2-1) in a single day.

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The answer is a big YES. Cruise ships dump over 1 billion gallons of waste each year into the ocean. This was back a year ago. Google it and you will find a large list of what they can dump a few miles off shore.

That’s according to Friends of the Earth, a non-governmental environmental group, which used US Environmental Protection Agency data to calculate arrive at that gross figure. The EPA estimates that single 3,000-person cruise ship pumps 150,000 gallons of sewage—about 10 backyard swimming pools’ worth—into the ocean per week. One vessel in an EPA study produced 74,000 gallons of sewage (pdf, p.2-1) in a single day.

 

 

Not entirely sure I see a huge problem here. Cruise ships don’t dump raw sewage near the shore where it would be a problem. But really, human waste, animal waste, fish waste, etc, is a normal part of life and works its way back through the environment as a natural thing. There would be nothing inherently wrong with dumping huge piles of human waste on the ground to be broken down naturally, either, except that there are quite a lot of us, and it wouldn’t be nice or healthy to live near a huge pile of poo. Toxic chemicals, plastics and other unnatural waste is a problem, and cruise ships should not be dumping those in the ocean, and I think/hope they are now pretty good about not doing that.

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Nearly every cruise has a day when the crew takes questions from passengers. On Equinox a couple weeks ago, Captain Kate explained that the 'gray water', i.e. sink and shower and even toilet after the solids are filtered out, is treated to drinking quality (but she hadn't tried it) before dumping into the sea. The solid sewage is filtered out and solidified into pellets rather like hockey pucks, and burned. Food waste is fed to the fish. Paper, cardboard, plastic is what you see being offloaded in port. EM

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As I understand it the sewage onboard is treated much like it is in a land treatment facility and only the treated (gray) water is discharged.

 

I’m not sure which, if any cruise lines do this, but I think untreated sewage is still allowed to be discharged at a sufficient distance from land, ie 12 nautical miles.

 

I found a presentation on an international agreement which mentions this: http://www.mar.ist.utl.pt/mventura/projecto-navios-i/en/sd-1.2.5-marpol-2.pdf

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Okay. That "Friends of Earth" thing gets trotted out on a regular basis. It was not correct when published, nor is it correct today. Let's look at the various waste streams a cruise ship develops:

 

Gray Water: (water from sinks, showers, laundry) Legally, this can be discharged without any treatment at least 12 miles from shore, but here is where the FOE statement falls flat. There is a maximum discharge rate for untreated sewage based on the ship's speed, draft, and beam. A ship the size of Oasis of the Seas, for instance, can only discharge 73 cubic meters of waste water per hour, while traveling at 18 knots (less if slower, more if faster). Given about 14 hours per day outside of 12 miles from land, that means she could discharge a maximum of just over 1000 cubic meters of waste water. Sounds like a lot? Not when you consider that Oasis generates 2000-2500 cubic meters of just gray water every day, so the question is, what does she do with the excess? Rather than raw discharging some of the sewage, and holding the rest for treatment, the ships have found it is much easier to treat it all and then discharge it.

 

Black Water (toilets): This must be treated onboard provided the ship is equipped with a sewage treatment plant, which all ships are required to have since the 70's. A ship can only discharge untreated sewage, despite what the FOE says, when their treatment plant is not working, and each discharge of raw sewage must be recorded with date, time, lattitude and longitude, and a reason why the system was not working. Long term "out of service" can result in fines and loss of class certificate and certificate of registry, without which the ship cannot sail. What 95% of the world's ships use is a system similar to a septic tank on land, where the sewage is held for a time allowing bacteria to digest the waste, before sending it overboard. Cruise ships will mix their black and gray water and send it through an "Advanced Waste Water Treatment Plant", which does much the same as the septic tank system noted above, but which handles vastly larger quantities of waste water, and at the same time treats this water until it is nearly clear, fresh, drinkable water, before it goes over the side. The sewage treatment plants are simple to operate if the flow is constant, but difficult in times of starting/stopping or changes in flow, so it is not in the ship's interest to only treat sewage when close to land and then stop treating it when at sea. Further, some states in the US require periodic third party testing of sewage plant effluent quality, and national port state control inspection can require testing of effluent. While most nations don't test this as part of Port State Control, a few nations, including the US do.

 

As noted by a previous poster, there is some solid matter left over from the AWWTP operation, but due to the design of the systems, this is 98% paper fibers. While your septic tank at home will eventually digest paper fibers (they are, after all, biological), the ship processes waste water so quickly that there isn't time to digest the tough paper fibers. This sterilized solids will either get pumped overboard, or incinerated onboard.

 

Food Waste: This is ground up, made into an oatmeal like slurry, and discharged overboard, or incinerated onboard.

 

Oily Water: all oily water generated in the engine room must be treated using an "oil water separator" to remove the oil down to the acceptable level of 15ppm, and is then pumped overboard. The oil removed from this water, along with other oil wastes and sludges, are either incinerated onboard or pumped ashore to reception facilities that either recycle it or incinerate it.

 

Solid waste: This comes in many forms, all of it is prohibited from being sent overboard. What can be recycled is recycled ashore (cardboard, plastics, glass, metals, batteries), others are landed ashore for proper, legal, disposal (incinerator ash, crockery, hazardous materials and chemicals), and others are incinerated onboard (paper).

 

Now, as for the problems associated with dumping raw sewage, either on land or at sea, there is a problem with it, as human waste contains many harmful bacteria and viruses, and proximity to it can be unhealthy. Further, large concentrations of it can kill off an ecosystem, or cause a change in the eco-system like an algae bloom which depletes oxygen in the water and suffocates marine life. This is one reason that there is a maximum discharge rate for untreated sewage, so that there are no high density discharges in a small area, it must be spread over a larger area that can handle the influx of bacteria and nutrients.

 

Are there violations and problems associated with waste management at sea? Unfortunately, yes. Are things better than decades ago, even considering the increased size of the world's merchant fleet? Yes. Can more be done to improve the record? Yes. And I will say that the cruise lines as a whole tend to be the most environmentally conscious group of shipowners out there, though one cynical reason is that a cruise ship has far more cell phone cameras onboard than a container ship, and everyone knows about the rewards for reporting environmental violations.

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I’m not sure which, if any cruise lines do this, but I think untreated sewage is still allowed to be discharged at a sufficient distance from land, ie 12 nautical miles.

 

I found a presentation on an international agreement which mentions this: http://www.mar.ist.utl.pt/mventura/projecto-navios-i/en/sd-1.2.5-marpol-2.pdf

 

According to Cheng's post above raw sewage can only be discharged if the treatment plant isn't working and then under specific conditions. When I was in the Navy in the 70's and 80's once we were outside 12 miles everything went into the sea. On my last ship in the early 90's the Navy was making big strides environmentally and all trash was held until the ship reached port (not sure what happened if an extended at sea period was needed but I have my suspicions) and sewage was held in contaminated holding tanks until they could be pumped out in port.

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According to Cheng's post above raw sewage can only be discharged if the treatment plant isn't working and then under specific conditions. When I was in the Navy in the 70's and 80's once we were outside 12 miles everything went into the sea. On my last ship in the early 90's the Navy was making big strides environmentally and all trash was held until the ship reached port (not sure what happened if an extended at sea period was needed but I have my suspicions) and sewage was held in contaminated holding tanks until they could be pumped out in port.

 

Yes, I remember back in the 90's when the USS Kennedy made Portland her "second home port" and called every couple of years. The one thing you noticed right away was the "honey" barge tied up alongside dealing with the waste from 5000 swabbies. At that time, it wasn't considered "mission conducive" to have a sewage treatment plant that could take combat damage and take out the waste water system, so it just went over the side. Always thought it was kind of funny that pleasure boats were required to have holding tanks and treatment plants, but the Gray Funnel Line could do whatever it wanted.

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According to Cheng's post above raw sewage can only be discharged if the treatment plant isn't working and then under specific conditions. When I was in the Navy in the 70's and 80's once we were outside 12 miles everything went into the sea. On my last ship in the early 90's the Navy was making big strides environmentally and all trash was held until the ship reached port (not sure what happened if an extended at sea period was needed but I have my suspicions) and sewage was held in contaminated holding tanks until they could be pumped out in port.

 

Yes, I always learn a lot from Cheng’s posts!

Edited by lisiamc
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The answer is a big YES. Cruise ships dump over 1 billion gallons of waste each year into the ocean. This was back a year ago. Google it and you will find a large list of what they can dump a few miles off shore.

That’s according to Friends of the Earth, a non-governmental environmental group, which used US Environmental Protection Agency data to calculate arrive at that gross figure. The EPA estimates that single 3,000-person cruise ship pumps 150,000 gallons of sewage—about 10 backyard swimming pools’ worth—into the ocean per week. One vessel in an EPA study produced 74,000 gallons of sewage (pdf, p.2-1) in a single day.

.... https://www.telegraph.co.uk/travel/cruises/what-happens-when-you-flush-the-loo-on-a-cruise-ship-/ ... the times they are a changing
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Yes, I remember back in the 90's when the USS Kennedy made Portland her "second home port" and called every couple of years. The one thing you noticed right away was the "honey" barge tied up alongside dealing with the waste from 5000 swabbies. At that time, it wasn't considered "mission conducive" to have a sewage treatment plant that could take combat damage and take out the waste water system, so it just went over the side. Always thought it was kind of funny that pleasure boats were required to have holding tanks and treatment plants, but the Gray Funnel Line could do whatever it wanted.

 

Yep, the government has a way of exempting itself from the standards imposed on others. I understand that new ship design is taking all of this into account but since I've been out for 26 years I have no updated info.

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Yes, I remember back in the 90's when the USS Kennedy made Portland her "second home port" and called every couple of years. The one thing you noticed right away was the "honey" barge tied up alongside dealing with the waste from 5000 swabbies. At that time, it wasn't considered "mission conducive" to have a sewage treatment plant that could take combat damage and take out the waste water system, so it just went over the side. Always thought it was kind of funny that pleasure boats were required to have holding tanks and treatment plants, but the Gray Funnel Line could do whatever it wanted.

 

What was funnier was the requirement on Chesapeake Bay for no discharge from pleasure craft.

 

So you would go to a marina and have your holding tank pumped out, or dump your chemical toilet. Into a system that dumped it untreated into the Bay.

 

And in the case of chemical toilets, added the treatment chemicals, many of which contained formaldehyde.

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Thanks for posting this and clearing up some of the misinformation.

My last cruise which was on the Konningsdam, in a lecture about improvements , the speaker touted their on board treatment plant surpassing many of those in the US as part of a new effort on Holland America to try to be greener. True or not I don't know but I hope it is.

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According to Cheng's post above raw sewage can only be discharged if the treatment plant isn't working and then under specific conditions. When I was in the Navy in the 70's and 80's once we were outside 12 miles everything went into the sea. On my last ship in the early 90's the Navy was making big strides environmentally and all trash was held until the ship reached port (not sure what happened if an extended at sea period was needed but I have my suspicions) and sewage was held in contaminated holding tanks until they could be pumped out in port.

 

I remember dumping A LOT of crap over the side of the big grey ships in the early 90's. Trash call a couple times a day. (plus the unofficial midnight trash call). The stream of garbage following us after meal times. Pumping down the bilges, grey water and CHT system before sea and anchor detail was set so we could get on liberty quicker. Was not unusual at all to hear a "splash" or two while enjoying the night sky while in the middle of the pond at night. Ahhhh the "god ole days" ;)

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