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Hi problem is most of us have a limited experience of makes other than the one we have and so are not experts. We looked at what was available in our area and went for a Desjoyeaux 5 by 10 metres with a plastic liner and Roman steps. Others we looked at included Ever Blue and there are quite a few others which I will leave to other folk to either decribe or dare I say promote.

The reason we went for Desjoyeaux is that we liked the lack of plumbing needed as everything was contained in a single unit that hung on one end of the pool and the price was competitive. The filter is a micromesh bag that can be hosed off or put through the washing machine on a rinse cycle so no back washing as such. Two bags are provided so one on and one in the wash.

We chose the saline pool option with an electrolytic cell to generate chlorine and have not needed to use other chemicals as some do. The running costs have proved low as the only chemicals purchased are salt, about 4 to 5  of 25kg bags once a year. About 15 bags initially provided by the installer. The pool stays reasonably clear of green algae and the pump and electrolytic cell consumes about 500 watts between them. We run it about 6 to 7 hours a day in the swimming season and overnight if it is likely to freeze  in Winter. We chose not to winterize the pool by significantly lowering the water level, adding chemicals and removing the pump. Rain in Winter may however require the pump to be used to remove excess water should the level get too high in the pool. The pump failed and was replaced after nearly 7 years, easy to DIY, and that seems a reasonable life given the number of hours running time.

We went to see some installations before we purchased and most big pool suppliers should be able to let you do this. All in all we are quite happy with it but do bear in mind that we have little experience of other makes. Good luck...............................JR 

PS I should have said that Desjoyeaux seem to have agents over a large part of France so the service you get will depend on each individual agency. On looking on-line I have found certain agents who have not always pleased their customers but I think that would be the case with any product, like Renault cars for example, but that is another story. Ours is located in Niort and we are satisfied with them so far. 

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I can help with identifying the 1991 European Union Directive.

It's this one:

http://ec.europa.eu/environment/water/water-urbanwaste/directiv.html

that's to say, the
"Council Directive of 21 May 1991 concerning

urban waste water treatment (91/271/EEC)". And it's in English, too.

But I'd be grateful if PoolGuy could say which part of it applies to privately-owned swimming pools in rural areas.

However, since EU Directives don't have any force at all in member states until each one puts it into effect by introducing its own laws, I'd also be grateful if could point us to the French law that introduces the directive into the French legal system. I couldn't find that one.

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Interesting. There is a lot on American sites about discharging pool water, quite a few states ban discharge into waterways and storm drains leading to waterways but allow discharge into sewers or onto ground within someone's property. There is a suggestion that accumulated salt deposits may damage certain types of vegetation and a recommendation not to discharge pool water in the same place each time if in the garden. They also seem to suggest a limit to the flow rate when discharging into drains but I would have thought that would be a concern about the risk of flooding or overloading the system.

Still not found any French sites about the law in specific terms about this or indeed sites presenting good sound evidence about any significant risk to flora and fauna. It would also appear that the discharge from a pool treated with chlorine tablets also releases salt into the environment, see chem geek et al, so are they also to be condemned? Nobody wants to do anything unnecessarily or easily preventable to damage the environment including me............................JR

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It's a matter of degree and I believe that's the point PoolGuy was making.  An SWG pool is going to have typically 3-6 times the salt level of a non-SWG pool so any dumping of the water is going to be that much more concentrated.  Clearly one can dilute with fresh (tap) water to lower the concentration, but for the same volume of discharge from the pool you're going to get a lot more absolute amount of salt introduced into the environment.  The fact that non-SWG pools have chlorine added and that this converts to salt just means that you can't get that level towards zero, but it's still far lower than in an SWG pool.

Where I live, the issue isn't so much about salt as it is about water itself.  This year we are going to have water rationing and since this occurs about once a decade, pools in our area are often installed with cartridge filters to avoid the backwashing issue.  They also often have pool covers which eliminate evaporation.  I can tell you from my own pool that this significantly reduces the amount of wasted water or introduction of anything into the environment (my cartridge filter is oversized so I only need to clean it about once a year).  Nevertheless, to avoid buildup of salt, organics, etc. in the pool water, I use winter rains to dilute the water by taking the water from the pool cover pump and adding it to the pool that then overflows into a sewage drain (not a storm drain, since that goes to the Bay -- our local law requires pool overflow to go to a sewer drain).

The bigger problem water treatment plants have with salt is from the discharge of salt brines used to regenerate water softeners.  A brine (saturated salt) solution is around 350,000 ppm equivalent or over 100 times that of an SWG pool [EDIT] (many water softener filters regenerate at 10% salt or around 100,000 ppm so over 30 times that of an SWG pool) [END-EDIT].  Of course, the volume of water is much lower than a pool, but compared to backwash volumes it's somewhat comparable since 40-70 gallons is the typical volume of water used during regeneration.  The frequency of regeneration will depend on the hardness of the water and amount of water used, but overall it seems that waste water treatment plants are generally more concerned with water softeners than they are with SWG pools.  Of course, that doesn't make the SWG situation a non-issue -- it just puts the overall waste water treatment process into perspective.

Richard

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Well like you the water we pump from the pool is only when we have had a lot of rain and the pool water level gets too high in Winter. That might only be 4 or 5 times a year and only enough to lower the level by a few inches. We have to discharge into the ground as here in the wilds of the French countryside we don't have the luxury of a sewer system, just a fosse and you must not fill that with pool water! So I don't think we are putting that much salt into the environment.

No back washing, as I have said, we just put the filter bag, 6 microns, in the washing machine every 4 to 5 days in the swimming season on a rinse cycle. Items like bits of leaves, worms and the odd frog having been taken out first. I often wonder if the test kit, by colour matching, is good enough for ph and chlorine measurement but within the limits of that system our pool water looks ok. We use a robot to clean the pool and that gets most of any muck off the bottom. The robot filter bag being washed under the tap afterwards.

So we may not be green but will watch for further info on the law and enviornmental recommendations for when the electrolytic cell fails and consider what system to go for then.....Cheers.......JR

PS I monitor the amount of salt needed to be added by measuring the current drawn by the electrolytic cell, if lower than normal I add salt until it reads between 10 and 12 amps and this seems to work ok but I gather there are test kits for this though not in the local supermarkets here.

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