Using river water for brew?

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Cor. A real live water treatment worker sticking their head over the parapet - must take a shot at that!

"UK tap water is very consistent" you say, so why does the "alkalinity" of tap water, probably the most important aspect of treating brewing water, vary so widely (water with source in acid moorland)? For example last year I couldn't get my mash pH above 5.0-5.1, this year I'm seeing 5.7 and backing off (calculated) alkaline salt additions quite considerably. Calculators are no help (I use Bru'n Water).

Chlorine content will vary wildly too, but that probably has acceptable reasons and is easily dealt with (metabisulphite doses are not measured accurately and are overdone most times - presuming it works).

Welsh Water is one of the utilities I cover; the alkalinity and pH and chlorine levels of the water you receive are very tightly controlled - and they will happily give you their data for your area. They will certainly NOT be supplying at pH of 5.0; target range will be 7.0 to 9.0 max normally, free chlorine usually 0.2 to 0.5mg/l; alkalinity/pH might be artificially increased depending on your supply area typically using lime or caustic. Your mash could well be 5.0 however depending on what you make it with - but I bet the incoming tapwater is not. If it is, your test method is wrong - or you need to let DCWW know. I have never bothered to check start or final pH of my brews; not sure what it would tell me. NW Wales water is generally quite thin, low conductivity with little alkalinity/buffering.
 
Welsh Water is one of the utilities I cover; the alkalinity and pH and chlorine levels of the water you receive are very tightly controlled - and they will happily give you their data for your area. They will certainly NOT be supplying at pH of 5.0; target range will be 7.0 to 9.0 max normally, free chlorine usually 0.2 to 0.5mg/l; alkalinity/pH might be artificially increased depending on your supply area typically using lime or caustic. Your mash could well be 5.0 however depending on what you make it with - but I bet the incoming tapwater is not. If it is, your test method is wrong - or you need to let DCWW know. I have never bothered to check start or final pH of my brews; not sure what it would tell me. NW Wales water is generally quite thin, low conductivity with little alkalinity/buffering.
The mash pH will be different from the tap water pH. It's the calculated prediction of mash pH that needs to know the "alkalinity" of the water (in say "ppm as CaCO3", not pH which is of little value to the predictions).

The most recent (private, March 2019) analysis of my water had alkalinity as 8ppm as CaCO3. Dwr Cymru doesn't provide "alkalinity" (or temporary hardness) but it could be inferred (?) from information they do give out (pH, "hardness") along with an estimate of bicarbonate - it was much, much, lower than the analysis (so perhaps I did that wrong, but trial and error came out at 1.1ppm as CaCO3).

Mash pH predictions were good up until last year, good after adopting the private analysis, now leading to high (alkaline) outcomes because something has changed with the supply again. I have whinged at Dwr Cymru but it hasn't been useful.

"UK tap water is very consistent"? Not by my experience (although I accept it is consistent for normal household use).
 
Aye, a borehole would be ideal. But I don't think that will be an option; the nearby Irish Sea won't help either. Nor will "rivers" be involved; we've heard earlier about the Mawddach being full of cyanide, arsenic, mercury and … gold :rolleyes: mmm. The sheep do get everywhere, including the drinking water reservoirs, but I don't think the water will be used unboiled?

The water ought to be good, they used it at the Ginger Beer factory for sometime on the other side of the hill. I bet it doesn't change as much as the tap water (outside droughts or deluges). Not "magical" you say - careful, this is Wales and that comment could be seen as heresy (punishable by … well that might of changed recently, but I bet it will involve a sheep).

This isn't talking about some brook running through the farmer's fields; it's one of the biggest lumps of rock sticking out of the Welsh landscape, and it doesn't have smelly trains full of tourists trundling up it like another Welsh rock nearby.


Coming from wales i've heard all the jokes, but my favorite is :

Q: what do you call a sheep tied to a lampost?
A: A Leisure centre.
 
The mash pH will be different from the tap water pH. It's the calculated prediction of mash pH that needs to know the "alkalinity" of the water (in say "ppm as CaCO3", not pH which is of little value to the predictions).

The most recent (private, March 2019) analysis of my water had alkalinity as 8ppm as CaCO3. Dwr Cymru doesn't provide "alkalinity" (or temporary hardness) but it could be inferred (?) from information they do give out (pH, "hardness") along with an estimate of bicarbonate - it was much, much, lower than the analysis (so perhaps I did that wrong, but trial and error came out at 1.1ppm as CaCO3).

Mash pH predictions were good up until last year, good after adopting the private analysis, now leading to high (alkaline) outcomes because something has changed with the supply again. I have whinged at Dwr Cymru but it hasn't been useful.

"UK tap water is very consistent"? Not by my experience (although I accept it is consistent for normal household use).
8ppm as CaCo3 seems likely if you are NW Wales; you are correct that pH is a poor predictor. What sort of test method are you using btw? I should have stated that UK tap water standards are consistent - and very good. But due to the huge variation in sources - there are big variations in what comes out of the tap. Anybody living on a chalk fed source in Wiltshire or Anglian groundwater or a Thames river source will see substantial differences to you.
 
"UK tap water is very consistent"? Not by my experience (although I accept it is consistent for normal household use).
... but come on PeeBee, obviously "normal household use" and potability are the qualities that the utility companies manage toward, and since alkalinity does not come into those qualities then you know it's fair for them to claim consistency, really, don't you wink...

... so why does the "alkalinity" of tap water, probably the most important aspect of treating brewing water, vary so widely ...
... well, because air pollution is variable, so acidity of rain is variable, as is rate of rain falling, making the rate of that water dissolving the carbonate bearing minerals it passes over/through variable, and hence alkalinity of the water being processed and delivered to your tap variable :?: ... but surely you knew that? When you had a sample of your water tested, did they not explain to you that this was only a single analysis, of a single sample? From what you're describing it sounds like you've invested in some way of measuring mash pH, but have you not invested in an alkalinity testing kit so you can test your water for yourself, on brewday? Since, as you say, alkalinity is ”probably the most important aspect of treating brewing water" :?:

Cheers, PhilB
 
@PhilBrew. The "normal household use" sentence was in recognition that Dwr Cymru were doing there job. I'm only pursuing this line in defence of me saying upland water collection is a valuable source of water for brewing. As per the OP - remember that? (Says me who is notorious for hi-jacking threads - but I am trying to keep this one on course).

I measure pH with a cheapo Chinese "pen" meter, but replace them fairly regularly and keep on top of the calibration with commercial buffer solutions. I've just replaced the pH meter again with a less cheapo "pen", but this one has 3 point calibration and replicable sensors instead of the extra cheapo single point calibration naff pens (I still don't pretend to read to two decimal places). I do have an alkalinity test kit - the commonly used Salifert kit. If I remember rightly it measures down to 30ppm. Read @alice-edmund's last post and you'll appreciate how useless such kits are for me (hopefully I'm also answering Alice's question about what test method I use).

I'm considering a cheapo TDS pen (or conductivity tester - same thing I believe) to answer the minimum ppm resolution conundrum. Why bother when the water has so little in it? The trouble is such water has very low buffering capacity, pH is a measure of buffering capacity, small changes by Dwr Cymru that effect alkalinity have a big impact on predicting mash pH, and faced with this I'm still supposed to make an effort to keep mash pH in-between 5.3 and 5.6.


I'm aware that climate has an effect on water analysis, but Alwen reservoir (the only source of my water I'm told) is a pretty big "sink" for changes. I know the drought last year would have caused problems, but I started having problems pre-dating the drought.


My thanks goes to @alice-edmund who is making an effort to dissect my issues with my tap water (I haven't got access to an unsullied source of upland water despite my location very near to Snowdonia).
 
Hi PeeBee

I do have an alkalinity test kit - the commonly used Salifert kit. If I remember rightly it measures down to 30ppm. Read @alice-edmund's last post and you'll appreciate how useless such kits are for me (hopefully I'm also answering Alice's question about what test method I use).
... OK, so you have a testing kit and I appreciate why you may not feel you need to use it every brewday, but when this happened ...
For example last year I couldn't get my mash pH above 5.0-5.1, this year I'm seeing 5.7 and backing off (calculated) alkaline salt additions quite considerably.
... did you not consider that things must have changed considerably? A change in alkalinity, even quadrupling from 8 up to 32, wouldn't result in a change in mash pH so extreme, so did you not retry that alkalinity testing kit then?

I'm only pursuing this line in defence of me saying upland water collection is a valuable source of water for brewing. As per the OP - remember that? (Says me who is notorious for hi-jacking threads - but I am trying to keep this one on course).
... and I'm posting here by way of reminding you, and the OP, that getting your water tested only lets you know what your water was like (not what it is like) ... and even if the analysis tells you that the water has the square-root-of-diddly dissolved in it, you should still set yourself up to verify it still has little in it, on occasions ... and having set yourself up with the capability, you should probably use it :?:

Cheers, PhilB
 
Going back to the whole point of brewing, it was one reason why people ONLY drank ale or small beer - because it was safer that well or river water.
But this would be back when pesticides and fertilisers hadn't been invented.
I used to live on a natural spring. When it rained a lot we would have minor springs all over the place around and under the house! But mostly at the bottom of the paddock was the main spring that fed 5 houses and a large farm.
If you can get water from a spring rather than a river then it should be free of land runoff. Ours was ok apart from one year when black bits were found in the water. Turned out the sump had frogs in it, and several disappeared into the pump. sick...
 
... did you not consider that things must have changed considerably? A change in alkalinity, even quadrupling from 8 up to 32, wouldn't result in a change in mash pH so extreme, so did you not retry that alkalinity testing kit then?
Well … I did consider it, but I was blaming the water company (might still be?) fiddling with the pH. I'll dig out the test kit as you suggest and see if anything dramatic comes out of it.

The change in alkalinity isn't as huge as you imply: I dialled back to zero alkalinity last year (in Bru'n Water) yet still got mash pH of 5.0. That was then, after the private test alkalinity had jumped to 8 (ppm as CaCO3) and was working well for a bit, but when I got the most recent mash pH of 5.7 the prediction was 5.4.

A TDS/Conductivity meter might be my answer to on-the-day tweaking?

I don't want to get too farty about it, I just want to reliably fall in the 5.2-5.6 mash pH bracket like before 2018, and perhaps have some control of which end of that bracket my mash will fall into. And do it with the tap water, not by walking up the hills with a bucket!



My notes from 2018 water analysis in Bru'n Water adapted from Dwr Cymru's 2018 report was (note alkalinity is being expressed in different units):
Water report published 24/1/2018. Calcium estimated, Magnesium no detectable quantities. Alkalinity from test kit as 0.1 (lowest) but estimate 0.022meq/L because predicted pH usually too high (about pH+0.2). Increased calcium by 7.6ppm to balance reported sulphate figure (Salifert test 13/8/18 20-30ppm Ca). Update hardness figures to match.

Calcium is reported as 19ppm by Dwr Cymru, but that is a calculated figure from hardness (47ppm as CaCO3).
 
Why not just do 2 brews? One from the tap and one from the river? See which one you like?

Nearly on-topic..... years back before I brewed anything I stayed on recommendation at a campsite on a farm in the Dalby forest. They said "try the water from our tap, it's out own bore hole and it's really good" I sort of ignored it, but later that day went to fill up for a cuppa, and tried it straight. It was utterly delicious! I mean, mind-bendingly good! It sounds silly, but drinking that water was a revelation.
Unfortunately I'm not about to drive 350 miles round trip to go get some for my next brew though....
 
Why not just do 2 brews? One from the tap and one from the river? See which one you like?
@tropicalpalmtree: Yours! I've done what I said I usually do and hijacked your thread.

But your choice of "river" in the title is misleading a lot of folk. I'll try to put that right with this photo I snipped off Google (taken by "Rob Allen" it says):
Capture.PNG

Obviously the OP isn't referring to the "river" (estuary) in the foreground. The OP is referring to streams in those hills (that's Cader Idris in the background, and the Ginger Beer referred to earlier is Idris's - rather along time ago when it was brewed about here!).
 
So many points from the above....
OK, The Alwen WTW had big investment about 5 years ago and is in pretty good shape though we are supplying a new dose system for part of the plant at the mo. Your alkalinity test kit is probably too inaccurate at its low range of 30mg/l - depending what it is measuring it as. Utilities don't regulate 'alkalinity' as such but do it indirectly with pH meters as this is an 'easy' measurement - and you need expensive, wet chemistry methods to do alkalinity. You only need to measure pH to 1 decimal point - that's quite good enough. Conductivity and TDS are not the same - though a a graph of the too is linear (not 1:1) for most UK tapwaters. TDS is normally about 7/10s of conductivity. Alwen is a rainwater catchment source - so what comes in varies - but frankly the hypothetical variation between 8 and 32 will be nothing compared to what you do in the mash. Basically I think I am saying you are looking at the tapwater for problems. It's possible they sent out non-OK water - but it's pretty rare and if you're supplied via service res or similar there would have been blending - but if you want to use river water or a local spring/well (better) - feel free; filter it and boil it though. What are you going to wash all your vessels etc with?
 
if you want to use river water or a local spring/well (better) - feel free; filter it and boil it though. What are you going to wash all your vessels etc with?
I spent my whole working life as a biologist, and I 100% agree that what you say is theoretically correct. And yet.......
In my last two houses, I used water originally derived from surface run-off, not a borehole, for brewing, and still do. I do not boil the whole wort - I do a partial boil and top up with unfiltered, untreated water. I also wash and rinse all of my equipment with unfiltered, untreated water.
I know full well that in doing this I am taking a risk of microbiological contamination. I have no theoretical way of knowing whether this is a high risk, or a low risk. I'm therefore taking an empirical approach. So far, I have not had a single episode of spoilage. Have I been very lucky, or is the risk of spoilage very low? I haven't a clue. But until I get an issue, I'm certainly going to carry on as I am doing.
Now here's an interesting thought, though. I'll brew with it, but no way would I drink the stuff that comes out of my tap!! I will boil it and make tea, but for drinking I buy Tesco's cheapest !
 
Does the act of fermentation itself destroy pathogens?

Sounds like some knowledgeable people here.

If it does, then maybe the old methods of "Scold your barrel before the next brew" might be all that was needed with a poor water supply.

.....and how did they stop spoilage before airlocks came along?
 
Does the act of fermentation itself destroy pathogens?
Well, as I said I'm not a microbiologist, but I think that strange-steve is on the right track here.
However, that isn't the whole reason for what I do.
My main concern for my drinking water is that it derives from run-off from farmland - both sheep and cows. Obviously, where I live, there will be other animals involved. Probably deer, foxes and hares are the most prevalent. Although the water does go through a settling-tank process, I would not drink it because it may contain pathogens, and I'd probably be more worried about parasites. Supermarket bottled water is a lot cheaper than a filtration/ultraviolet sterilisation system. (I have one, but I ripped it out & it's now in storage).
In brewing, my main concern is for a wild yeast or bacterial infection to spoil my brew My brewing process is unhurried. Most of the water is boiled, but not all. I routinely top up with raw water - but if I ever get an infection then I will review this practice. I normally drink my pint of beer at least a month after I pitched, usually more. I may be wrong, but I believe that the chances of a pathogenic bacterium surviving the long journey to my eventual pint of beer is negligible. The chances of a parasite doing so must surely be close to zero.
So, I will continue. But in no way could I say that what I do is "Best Practice"
 
@alice-edmund: Thanks for the extra info. I've had time to digest most of it now.

Your alkalinity test kit is probably too inaccurate at its low range of 30mg/l …
Yes, I knew that. I used to use the calculator (Bru'n Water) to estimate alkalinity, but the calculator doesn't claim to estimate alkalinity, I'd just use other figures (pH and hardness) it did do to work backwards; but you've made me realise that what I was doing was using estimates to create estimates and compounding all the errors along the way. But I did modify it to match mash pH outcomes (empirically) and had been using 1.1ppm as CaCO3 quite successfully for a couple of years before 2018 (alkalinity of 0.022meq/L = 1.1ppm as CaCO3, a multi-step conversion using my own dodgy logic that no doubt introduced more inaccuracies).

To remind other readers of why I fart about with such minuscule figures: I rely on the calculators to predict the mash pH, to the point that a couple of years ago I wouldn't always bother to take mash pH readings as I could rely on the calculated outcome. Without the calculator I'd just be chucking stuff in and hoping for the best (although that's how we used to do it, but my beer is very much better now than how I used to do it so I'm inclined to put some credit behind water treatment even if I have no evidence for it).
Conductivity and TDS are not the same …
Thanks for clarifying that. I couldn't see how these cheapo meters could do both, but now I know! I'm still keen on using a TDS meter, but only as a quick check of whether, or not, things have changed again.
… if you're supplied via service res or similar there would have been blending …
I'm not aware of any "service reservoir" but one might explain the sharp change of temperature, from <10C in Winter to 18C in Summer. As for blending (of supplies) I don't think there is enough humanity about here to be worried about such contingency measures (it's Alwen or nothing?).
The Alwen WTW had big investment about 5 years ago and is in pretty good shape though we are supplying a new dose system for part of the plant at the mo.
That's the bit I'm going to take most interest in (whether I'm right or wrong!). I've seen so quite big variations in pH over the past couple of years (7.4 to 8.6). And changes in pH are going to reflect changes in alkalinity. If my water supply is being worked on currently maybe that explains the "issues" I get faced with. It would also explain why I'm not hearing of others having similar "issues" or others giving relevant advice (I'm not living alongside a substantial population about here).

… but if you want to use river water or a local spring/well (better) - feel free; filter it and boil it though.
Na. That's connected with the OP, which I've hi-jacked! I'll use the tap water. I do have a small river running by the bottom of the garden (occasionally the garden is the bottom of the river!). But I've no intention of using it!

Thank you very much.
 
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