Water Softeners and Drinking water supply

Highways

Hi,
Can anyone enlighten me on the law in relation to installing water softeners and the drinking water supply. My understanding is that installers of water softeners should run unsoftened water to the drinking water tap in the kitchen but I don't know is this just a recommendation or covered by bylaws? AFAIK it's required by law in the UK but I haven't been able to find a definitive answer for what applies here.

aah yes

Highways wrote: »

Hi,
Can anyone enlighten me on the law in relation to installing water softeners and the drinking water supply. My understanding is that installers of water softeners should run unsoftened water to the drinking water tap in the kitchen but I don't know is this just a recommendation or covered by bylaws? AFAIK it's required by law in the UK but I haven't been able to find a definitive answer for what applies here.

Softening all of a domestic household water supply, (or a commercial premises supplying drinking water to the public), ... is fine, in terms of water potability, also with all local Irish bylaws, Irish national plumbing codes and the European Drinking Water Directives.

The UK is a bit odd in this respect. It is odd for the fact that many soft water areas of the UK do not require householders to re-harden water for drinking purposes, soft water is still okay ...

... well, naturally soft water (rainwater for example), also many popular UK supermarket bottled waters are soft with virtually no calcium mineral content, and some may also have levels of sodium exceeding the strict tap water safe levels set by the EU by over 400%, but yet unregulated in UK bottled water. Vichy for example contains 1110ppm and Apollinaris contains 410ppm of sodium and many other higher sodium brands sold in the UK.

All that is required Europe wide, is that water is safe to drink and therefore meets the strict limits set by the EU and WHO. This is where the UK has a struggle with their odd plumbing code, as softened water meets EU water potability safety, due to its low trace level sodium content.


What happens when you soften hard water using ion exchange, is that hard water ions such as calcium and magnesium that cause household plumbing damage are removed, and trace level sodium ions are exchanged at a level of usually 80ppm to 160ppm, if hard water from 200ppm to 400ppm (total hardness) calcium carbonate or calcium equivalent is being softened.

Because the WHO (World Health Organisation), EU Drinking Water Directives, US EPA, and many other world leading water quality legislative bodies regard 200ppm sodium as the safe upper threshold level for potable drinking water, then softened water below this level is fine in almost all cases to consume.

But ... with general medical advice and in certain cases, those on ultra low sodium diets, or those following (below) 30ppm recommendations for infant formula feed, may choose to reduce sodium in the lowish traces levels found in softened water (on average at around 120ppm) down to 6ppm using simple devices such as RO (reverse osmosis) filter systems with their typical 95% sodium reduction ability, ... or instead feed a hard raw water or chlorinated and fluoridated mains water separately ?

If you are going to use an RO system anyway, then all manufacturers recommend they be fed off a soft water or softened water feed, ... they last twice as long, require almost half the maintenance, and provide a better quality of water.

Supermarket milk has 300 to 500 ppm of sodium, many cereals and soups along with bread, ham and processed foods often exceed 1000 ppm of sodium (or mg/l). The main area to look at when reducing daily sodium intake is food first of all, - a reduction of 50% can easily be achieved, and if softened water is the only liquid beverage a person consumes, there is the scope to reduce a further 5% margin.

Many modern high specification water softeners, when used on dirty well water can reduce a wide range of other contaminants, generally positive ions such as excessive iron or manganese, heavy metals, aluminium, radium also lowering ammonium, sediments and thereby improving not only the potability and aesthetics of the water, but actually rendering it much safer to drink.

antoinolachtnai

aah yes wrote: »

Softening all of a domestic household water supply, (or a commercial premises supplying drinking water to the public), ... is fine, in terms of water potability, also with all local Irish bylaws, Irish national plumbing codes and the European Drinking Water Directives.

In the case of Dublin City, this is the case, so long as you have the written agreement of Dublin City council in accordance with Regulation 34 of the Waterworks Regulations.