taking own water onboard

[Astro Flyer]

The ships use liquid chlorine. Since the chlorine is used in the potable water system as well, it is just easier to carry over the use of liquid chlorine for the pools. After all, can't add salt to the potable water, then everyone would have swollen ankles. :D

Thanks for the info & for your humor. :D

 

If anyone gets swollen ankles I think that's probably from salt used in recipes to the large amount of the food passengers consume during a cruise. :p

[Colo Cruiser]

Thanks for the info & for your humor. :D

 

If anyone gets swollen ankles I think that's probably from salt used in recipes to the large amount of the food passengers consume during a cruise. :p

 

It's the Butta.

[moki'smommy]

Well done. The only difference I will say is that when distilling sea water, if you allow it to reach 212*F, you will form scale from the minerals in the sea water on the heat transfer surfaces, which will diminish the capacity of the equipment. Therefore, ship's evaporators bring the "boiling" or evaporation chambers to 21" of vacuum, and water boils at 140*F at this pressure. This greatly reduces the scale formation, and the subsequent acid cleaning of the heat transfer tubes. Since the water is not boiled to 212*F, there is no "guarantee" that any microbes that "carried over" from the evaporation part to the condensation part, this is why the USPH requires the water to be chlorinated prior to it going into the tanks.

 

A ship's "evaporator" is what a moonshiner calls a "still" (short for distiller). It evaporates sea water using the heat from the diesel engines' cooling water, and then condenses it again using the sea water that is about to be evaporated (thereby cooling the distillate and pre-heating the sea water feed.

 

True--I assumed 1 atmosphere of pressure. If the ships use a vacuum, that significantly lowers the needed temperature.

[Chris86]

I have 2 princess cruises booked. One with sun the other with diamond. Interesting diamond offer 12 bottles of water for 8.49aud. However no sign for it on sun. Such a shame as it would save me bringing some bottles for ports. Especially since the PNG ports are isolated with limited opportunity for water purchase. However I will call princess closer to the sail date.

[GUT2407]

water is very inexpensive to buy if you pre order it. $6.90 for 12 500ml bottles

 

Seems they're no longer offering it in Australia.

[Chris86]

Seems they're no longer offering it in Australia.

 

Perhaps the sun class have limited storage than the grand class. Therefore eliminating certain packages?

[GUT2407]

Perhaps the sun class have limited storage than the grand class. Therefore eliminating certain packages?

 

It's disappeared on our Emerald cruise in December.

[RDC1]

I know of no ship or cruise line that adds minerals to the water produced onboard "for taste". In fact, the only commonly used treatment is to pass the water through calcium carbonate granules (the active ingredient in Tums) to neutralize the slight acidity of distilled water. The salty taste you had was caused by over-chlorination. And bottled spring water typically has more minerals than bottled tap water run through a reverse osmosis unit.

 

Even the charcoal filters used at the water dispensers onboard, at the ice makers, and the bar guns is not for taste, it is because the chlorine will build up scale in the mechanisms of these machines, though a change in taste is a side effect.

 

Some studies on humans drinking desalinated water indicate that it can cause problems, that is one reason why commercial desalination plants that feed community water systems usually add minerals back in (as well as for maintenance reasons). There is a very good paper from WHO on the subject. Surprised that ships would not add some minerals back in. For maintenance reasons if for nothing else, since distilled water tends to be more aggressive in its impact upon pipes and storage systems.

 

Though running it through the calcium carbonate will result in some minerals being added (calcium) that would resolve the maintenance issue to a large degree.

Edited July 6, 2016 by RDC1

[RDC1]

Well, several points to discuss here. Not only have I worked on cruise ships, which do use both evaporators and reverse osmosis water makers, but for decades on cargo ships, which use evaporators only to produce 100% of their water, and over those decades we have never added anything other than the calcium carbonate to this distilled water (which is exactly what comes from an evaporator), and the water is perfectly "palatable".

 

The post where you say I was talking about reverse osmosis only was because no bottled water supplier uses evaporators, unless they are selling distilled water.

 

Now, when you mentioned the water was "salty" on your cruise, I assumed you were referring to taste, not water retention, which is what I responded to. Now, if evaporation removes all of the salt from sea water, and reverse osmosis removes 98% of it, why in the world would you add it back in? Why not just let the equipment degrade a little so that it doesn't make quite as good a product and be done with it? Wastes a lot of energy to my thinking. And you were talking of adding "minerals" to the water, what other minerals (and salt is not technically a mineral, but I'll let that slide)? Now, with the fact that the USPH, the EU's ShipSan, and the WHO control every aspect of drinking water onboard ships, from the design and construction of the systems, to the operation and monitoring of those systems, to the testing of the water product, do you think they would allow uncontrolled additions of various minerals to be added to the water without a single comment about them? I don't.

 

Now, not all bottled water is "filtered" using a reverse osmosis unit, some of it is simply that, filtered. One thing I always find amusing is when folks say that RO (reverse osmosis) produces water with higher salt content. When folks have a water softener in their home, this uses salt to "re-charge" the softening agent, and if the homeowner is on a reduced sodium regime, what do you think the water softener manufacturer recommends be added to the house's water system? An RO unit to lower the sodium.

 

As to how chlorine affects water retention, I must apologize that my poor internet onboard is barely allowing me to keep up with this post, and I'm having trouble searching for links, but chlorine can replace iodine in the thyroid, causing lower metabolism. I will try later today to find some sources.

 

The following is a paragraph from a WHO paper that indicates why distilled water may be an issue. It may result in a shortage of electrolytes. Interesting aspect is that while it says that diuresis is increased by 20%, there is also an increase in body water volume.

 

http://www.who.int/water_sanitation_health/dwq/nutrientschap12.pdf

 

Results of experiments in human volunteers evaluated by researchers for the WHO report

(3) are in agreement with those in animal experiments and suggest the basic mechanism of the

effects of water low in TDS (e.g. < 100 mg/L) on water and mineral homeostasis. Low-mineral

water markedly: 1.) increased diuresis (almost by 20%, on average), body water volume, and

serum sodium concentrations, 2.) decreased serum potassium concentration, and 3.) increased the

elimination of sodium, potassium, chloride, calcium and magnesium ions from the body. It was

thought that low-mineral water acts on osmoreceptors of the gastrointestinal tract, causing an

increased flow of sodium ions into the intestinal lumen and slight reduction in osmotic pressure in

the portal venous system with subsequent enhanced release of sodium into the blood as an

adaptation response. This osmotic change in the blood plasma results in the redistribution of body

water; that is, there is an increase in the total extracellular fluid volume and the transfer of water

from erythrocytes and interstitial fluid into the plasma and between intracellular and interstitial

fluids. In response to the changed plasma volume, baroreceptors and volume receptors in the

bloodstream are activated, inducing a decrease in aldosterone release and thus an increase in

sodium elimination. Reactivity of the volume receptors in the vessels may result in a decrease in

ADH release and an enhanced diuresis. The German Society for Nutrition reached similar

conclusions about the effects of distilled water and warned the public against drinking it (7). The

warning was published in response to the German edition of The Shocking Truth About Water (8),

whose authors recommended drinking distilled water instead of "ordinary" drinking water. The

Society in its position paper (7) explains that water in the human body always contains

152

electrolytes (e.g. potassium and sodium) at certain concentrations controlled by the body. Water

resorption by the intestinal epithelium is also enabled by sodium transport. If distilled water is

ingested, the intestine has to add electrolytes to this water first, taking them from the body

reserves. Since the body never eliminates fluid in form of "pure" water but always together with

salts, adequate intake of electrolytes must be ensured. Ingestion of distilled water leads to the

dilution of the electrolytes dissolved in the body water. Inadequate body water redistribution

between compartments may compromise the function of vital organs. Symptoms at the very

beginning of this condition include tiredness, weakness and headache; more severe symptoms are

muscular cramps and impaired heart rate.

Edited July 6, 2016 by RDC1

[caribill]

It's disappeared on our Emerald cruise in December.

 

Maybe it was an experiment that has ended.

 

Carnival Cruise Lines offered a pre-cruise water bottle package at a great price but stopped allowing passengers from bringing even one bottle of water on board at embarkation and at ports. (They now have a big bucket to collect partially used water bottled when you re-board the ship at a port.)

 

Princess may have been experimenting with selling water pre-cruise at a reasonable price with the thought that if it worked out, Princess would then join Carnival in forbidding passengers from bringing any water on board.

[Astro Flyer]

Seems they're no longer offering it in Australia.

 

It's disappeared on our Emerald cruise in December.

The water package is still available on our Star cruise to Hawaii in January so maybe it's only in Australia where it's unavailable.

[fshagan]

Since the water that circulates around the ship is chlorinated, there is no special treatment required, but most ships use plastic piping for ease of maintenance. Distilled water has a tendency to attract minerals to itself, so metallic piping, even copper piping as used in homes, can be "attacked" by distilled water and corrode. Chlorine acts as a sanitizing agent effectively, only over a narrow range of Ph, so some acid is also injected into the water, to keep the Ph in this range (7.2-7.6, just slightly alkaline). The requirements for the water in use being pumped around the ship are that there must be a residual chlorine content of 0.5ppm at the furthest point from the chlorine injection site, so typically there is a chlorine monitor in the bridge head (bathroom), and this monitor controls the amount of chlorine injected to maintain the proper level everywhere in the ship.

 

I have a background in commercial hot water boiler systems, and the water is continuously circulating throughout the building in those systems as well. That's why you don't have a wait when you turn on the hot water like you do at home. Those systems use municipal water and typically will include a softener if the water is hard (a problem you evidently are not seeing with the flash steam / distilled water). You might see it with bunkered municipal water, but perhaps you blend it or use softeners as well..

 

A recommended free chlorine level in water systems is at least .2ppm, with the upper safety / taste limit at about 2.0 ppm, but most of our cities here in California are now using chloramines, with much less taste impact. That may be why the ship's water has such a strong taste of chlorine to me.

[apeller]

I'm sure this has been answered somewhere, but I was wondering what the policy is on bringing my own bottled water onboard? I will be on the Ruby Princess soon. I thought that I've read somewhere that it doesn't matter how much. So I can just bring an entire case of bottles in addition to all my luggage?

 

I often tape a luggage tag to the top of a case of water and send it straight to my room with my bags. I like having bottles to take on excursions,

 

I'm concerned that cruise lines will all stop allowing this because we recently got an email from NCL and they are prohibiting carrying most liquids aboard (including water), so chances are everyone will eventually follow. They claim it will speed up security when boarding, but of course it's more to do with $.

 

But for now, Princess has no issue with bringing water onboard.

[chengkp75]

Some studies on humans drinking desalinated water indicate that it can cause problems, that is one reason why commercial desalination plants that feed community water systems usually add minerals back in (as well as for maintenance reasons). There is a very good paper from WHO on the subject. Surprised that ships would not add some minerals back in. For maintenance reasons if for nothing else, since distilled water tends to be more aggressive in its impact upon pipes and storage systems.

 

Though running it through the calcium carbonate will result in some minerals being added (calcium) that would resolve the maintenance issue to a large degree.

 

I won't even try to say I understand what all that in the WHO paper means, I'm not a doctor, and have never played one on TV. :D As I've said, I've been drinking ship's water (and cargo ships don't use much shore water, so 90+% distilled) for 6 months a year for 40 years, and my real doctor says I'm in very good health. I will admit that one ship I was on that did not use the calcium carbonate (and it is actually called a "re-hardening" filter) I noticed my teeth getting sensitive. So, the re-hardening does work to remediate the action of distilled water. This is also why, as I say, that the ships will use plastic pipe throughout the ship, usually everywhere outside the engine room.

[chengkp75]

I have a background in commercial hot water boiler systems, and the water is continuously circulating throughout the building in those systems as well. That's why you don't have a wait when you turn on the hot water like you do at home. Those systems use municipal water and typically will include a softener if the water is hard (a problem you evidently are not seeing with the flash steam / distilled water). You might see it with bunkered municipal water, but perhaps you blend it or use softeners as well..

 

A recommended free chlorine level in water systems is at least .2ppm, with the upper safety / taste limit at about 2.0 ppm, but most of our cities here in California are now using chloramines, with much less taste impact. That may be why the ship's water has such a strong taste of chlorine to me.

 

No softeners used, but the percentage of shore water is usually less than half of total water production. As I say, shore water has to be "quarantined" until the tests come back negative, but once in use, the water tends to get blended with the distilled and desalinated water. Because the water is in constant circulation, it never gets real cold like your water at home, because it isn't buried 6' in the cool ground. We also find that if we continuously use from one tank and allow the returns to go to the same tank, the water heats up too much, so we will take from one tank and return to another, until one tank is empty or the other full, and then reverse the process.

 

I don't believe that municipal water supplies guarantee a free chlorine level at the "end user" (the home), since they have no way of knowing how long the water may sit in the pipes before it is used, so they chlorinate to the mandatory level at the plant, and out it goes. Since the ship's water is constantly circulating, and constantly being dosed with chlorine, in order to maintain a residual level at the furthest point, the water at the injection site (the engine room) will naturally be higher, and so those cabins whose water supply comes from the main closer to the engine room than others, will probably have a higher chlorine level.

[fshagan]

No softeners used, but the percentage of shore water is usually less than half of total water production. As I say, shore water has to be "quarantined" until the tests come back negative, but once in use, the water tends to get blended with the distilled and desalinated water. Because the water is in constant circulation, it never gets real cold like your water at home, because it isn't buried 6' in the cool ground. We also find that if we continuously use from one tank and allow the returns to go to the same tank, the water heats up too much, so we will take from one tank and return to another, until one tank is empty or the other full, and then reverse the process.

 

I don't believe that municipal water supplies guarantee a free chlorine level at the "end user" (the home), since they have no way of knowing how long the water may sit in the pipes before it is used, so they chlorinate to the mandatory level at the plant, and out it goes. Since the ship's water is constantly circulating, and constantly being dosed with chlorine, in order to maintain a residual level at the furthest point, the water at the injection site (the engine room) will naturally be higher, and so those cabins whose water supply comes from the main closer to the engine room than others, will probably have a higher chlorine level.

 

Municipal systems do attempt to "maintain" a certain residual at the furthest point in their system, at least here in CA where such testing is a state requirement. But there are quite a few problems in maintaining that, as the testing only shows a single point in time. The ship's system continuously recirculates and is (probably) continuously monitored at the furthest point as you mentioned, so it is likely to be safer from a pathogen standpoint than municipal water.

 

Recirculating water does cause heat from friction and it's surprising how much heat can be generated by water being pushed through the circulators. I have seen filter housings melt due to poorly designed systems (filter housings used in residential applications are often ABS plastic that has a lower melt point than the commercial filter housings that are either stainless or glass filled nylon). And the blending of the water sources is what I would expect.

 

I'm at a loss as to why people would experience swelling from the water on board, as everything points to exactly the opposite. The ship's water probably has less sodium than their water at home. The effect may be due to the diaeresis mentioned in the WHO report that isn't compensated for by the person because it is brand new to them, and they aren't taking in additional fluids. We need a doctor to chime in on that point, though. There is very little sodium added to the water from the sodium hypochlorite added to the system at 2 ppm.

[pablo222]

Well, several points to discuss here. Not only have I worked on cruise ships, which do use both evaporators and reverse osmosis water makers, but for decades on cargo ships, which use evaporators only to produce 100% of their water

 

Just a question ... why use reverse osmosis when you have so

much waste heat available for flash evaporators?

 

Thanks.

[chengkp75]

Just a question ... why use reverse osmosis when you have so

much waste heat available for flash evaporators?

 

Thanks.

 

The reverse osmosis units give flexibility for when the ship is slow cruising between ports. Two or three engine's heat is needed to run each evaporator, so if the ship is "paddling" along at 12-14 knots for timed arrival at next port, you could only run one evaporator, but the RO units will add in, using only electricity to operate.

[pablo222]

The reverse osmosis units give flexibility for when the ship is slow cruising between ports. Two or three engine's heat is needed to run each evaporator, so if the ship is "paddling" along at 12-14 knots for timed arrival at next port, you could only run one evaporator, but the RO units will add in, using only electricity to operate.

 

Thank you for the explanation.