Ocean water pool

[Tangbrandur]

Hi, me and my business partner in Iceland have had this idea recently to change a indoor public pool into a sea water pool, since it is probably going to shut down in a few months.
The pool is a indoors pool with 2 hot tubs outside and it is located next to the ocean. We have looked into the possibility to drill a hole in the ground to pump up the ocean water. I've been reading today about salt water pools but I have not found much about ocean water pools.
Our idea is to have a "Natural and green" style. And kinda prefer having the Salinity of the salt around the same as in the ocean. instead of adding fresh water to get the salinity down to 3000ppm

So my questions are:
Is it not possible to have a indoor ocean water pool with the salinity at 28-35 thousand ppm?
If it is what to I need to sanitize the ocean for pool standards
Could I use a salt chlorine generator?
Would that be enough to sanitize the pool?
If not what else could I use?
Do I need special filters?
Is there a post here witch has any info on ocean water pools?

 

[Swampwoman]

I suspect if you did a cost-benefit analysis you'd quickly abandon the plan...regular pool equipment is not designed to withstand that salinity, regular SWGs will not operate typically above 4 or 5k let alone at 30.

"Natural and green" -- if its public, I'd also be surprised if you could meet public health standards this route...plus the salinity would be corrosive in an indoor space and to the spas.

There are botanical filtration "natural" poos out there, but again, not suited to indoor or public settings, and i dont think youre likely to find much material at TFP on same because that approach is contraindicated by our focus on sanitized water.

Just my .02 but lets see if others hav ideas

 

[JoyfulNoise]

This has been discussed before, see HERE, HERE and HERE.

If your pool was constructed on the basis of being a standard pool, it is likely the seawater will be too harsh on the materials used for it's construction. There's also serious health and disinfection problems with just using seawater. While swimming in the open ocean is typically ok for people in terms of disease transmission and pathogen exposure, swimming in an isolated volume of seawater is not the same thing.

 

[Tangbrandur]

Forgot to specify that this pool was built around the 1940's and was an outdoor pool that they poured the seawater in and heated the pool with coal heaters. then in 1953ish they built around the pool and used fresh water.
As far as I can tell they did not change much the pool it self is made out of concrete and they no longer use coal heaters. And most of the building is made out of concrete and rust free steel. But then there is the problem of filtrating the pool and find special pool equipment that can withstand that salinity, I've seen some promising websites about that.

 

[Indigo blue]

Aren't the cruise ship pools filled with ocean water?


Sent from my iPhone using Tapatalk

 

[JoyfulNoise]

Aren't the cruise ship pools filled with ocean water?


Sent from my iPhone using Tapatalk

Most of the major cruise ship lines have desalination plants in board. If you ever go on a cruise, go on the in-ship tour if they offer it. It is AMAZING how much tech is aboard a cruise ship. There's literally thousands of crew members all working behind the scenes. It's like a small city floating on the water.


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006

 

[Swampwoman]

I'd guess the cruise ships desalinate because most people would not prefer ocean-level salinity

So while anything's possible, what would be the goal of using sea water?

From a cost-benefit standpoint, I'm guessing freshwater would be the way to go. There's nothing convenient about using seawater, though on the surface it might sound that way

 

[gwegan]

The vast majority of cruse ship pools are ocean water exchange pools. A few are desalinated pools. In most cruse ship pool water is pulled from the ocean, run through a large sand filter to the pool and then released back to the ocean. Because of the high exchange rate they don't sanitize or oxidize. Many people think there is chlorine in there but that generally is not the case. The US Coast Guard would not look kindly on discharging chlorinated water in the Virgin Islands.

That was probably the original design of this pool. Coal was relatively cheap. But I suspect the exchange rate wasn't that high.

Unless you are going to have a very high exchange rate you are going to need to sanitize and oxidize the pool and that is difficult with those high salt concentrations. Cruse ships don't even try.

 

[Indigo blue]

Gwegan, that's what I remember from being on cruises, I've been to about a dozen of them and mostly for work, I work in advertising so we shoot when people are sleeping or out on shore for the most part and I once asked why the pools were empty (don't remember what time of day it was) and they gave me a short version of your answer, so maybe they do that daily? Anyway, that's why I put a comment on here


Sent from my iPad using Tapatalk

 

[JoyfulNoise]

Not to quibble about cruise ships, but this CDC document seems to indicate that, while the water is indeed just filtered sea water, halogenation (disinfection) is required (see page 2). The Carvinal Cruise line website has a Q&A comment section and it seems to indicate that their pool water is treated seawater (treated with chlorine). Perhaps these regs only applies to ships that sail under a US flag (not many of those). But I would say that if cruise ships don't even try to chlorinate the pool water then I'm definitely not swimming in any cruise ship pools...yuck!


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006

 

[gwegan]

Joyful:

I saw those posts when I was researching. I don't give them much credibility. They were mostly anecdotal views of passengers. As most on here realize many blame high chlorine for their problems when the pool doesn't have it. So I don't think those folks are more accurate reporters re chlorine than most.

If you read the CDC document it talks about exchange pools and recirculating pools. The requirements you point out appear to only apply to recirculating pools. Most cruse ship pools are exchange pools. I wonder how much authority the CDC has over pool water on foreign flagged cruse ships?

Some ships have chlorinated fresh water pools. Almost all spas are fresh water and sanitized.

 

[JoyfulNoise]

Joyful:

I saw those posts when I was researching. I don't give them much credibility. They were mostly anecdotal views of passengers. As most on here realize many blame high chlorine for their problems when the pool doesn't have it. So I don't think those folks are more accurate reporters re chlorine than most.

If you read the CDC document it talks about exchange pools and recirculating pools. The requirements you point out appear to only apply to recirculating pools. Most cruse ship pools are exchange pools. I wonder how much authority the CDC has over pool water on foreign flagged cruse ships?

Some ships have chlorinated fresh water pools. Almost all spas are fresh water and sanitized.

Yep, I did read the document. I imagine most cruise ships can, and probably do, operate in both modes - exchange and recirculate. The distinction is probably made based on where the ship is physically located at the time of operating the pool. A ship sailing in international waters (>200 nautical miles from land) is subject to the laws and regulations of the country under which flag it flies (most cruise ship lines choose the Bahamas and other such smaller countries as they they typically have light regulations). Once a ship passes into the territorial waters of a nation (<12 nautical miles), it is then subject to the laws and regulations of the nation that it seeks port in.

Maritime law, especially in the area of waste water management, is very complicated as a cursory search of terms like "cruise ship" "waste water" and "maritime laws" yields lots of regulatory documents. Cruise ships also have to comply with the regulations of the State where the cruise ship is docked. So I won't speculate much further about how they operate their pools other than saying that both modes are likely available to ensure that they can comply with any specific situation they find themselves in.