Is getting a lab test water profile a waste of time?

[rjs3273]

I am happy to accept the short answer is no. It is always going to be interesting to see what you get and some information must be better than no information, but my question is not entirely flippant.

I have been searching through all the water threads in here and I can find very little information or discussion about the variability of water supplies from day to day. A few times there are general comments that water supplies "can vary". I found one quote of hard numbers from ajdelange (https://www.homebrewtalk.com/forum/threads/can-water-chemistry-change.261939/#post-3160266) saying his well water alkalinity can vary 70-80.

Both locations I have tested (Boulder, CO and Mountain View, CA) show huge fluctuations on the municipal water supply. I mean even up to a factor of ten in the most extreme cases.

Boulder: https://www.kandrsmith.org/RJS/Misc/boulder_water_profile.html
Alkalinity varies by factor of three from day to day (30-100 mg/l as CaCO_3)
Hardness varies by factor of five from day to day (40-200 mg/l as CaCO_3)

Mountain View: https://www.kandrsmith.org/RJS/Misc/mtnview_water_profile.html
Alkalinity varies by factor of eight from day to day (10-80 mg/l as CaCO_3)
Hardness varies by factor of six from day to day (10-60 mg/l as CaCO_3)

There is no mystery here. In both cases contacting the local water company confirmed there are multiple water sources and my water is coming from different places on different days. But my question is this, how typical is this? Who else out there has monitored their supply on a daily basis and established the stability of their supply? If my results are in any way typical of municipal water supplies either a one-off lab test or even the water companies annual numbers seem of very limited use. Unless you explicitly test your brew water on brew day surely only the grossest of first order water adjustments make sense.

But maybe my circumstance is atypical and most people are served from just one reservoir? Having your own well must be much more stable too. It will vary a bit but I find it hard to imagine it would vary through the year by a factor of ten.

Or alternatively someone can point out why my experiment is gibberish and not showing what I think.

To be clear I am not trying to start a fight or disregarding all the fascinating work that folk do on water chemistry. I greatly enjoy learning about it all. I am just curious how typical these large swings in profile are in different places.

 

[Derp]

Unless you explicitly test your brew water on brew day surely only the grossest of first order water adjustments make sense.

That's why I bought a reverse osmosis system and haven't looked back.

 

[ajdelange]

I'll just note that since the post of mine you linked I have taken alkalinity measurements at random over perhaps a year and found wider variation than 70 - 80 ppm. I'd say (I don't have the data here) that it is probably more like 60 - 110.

This particular aspect of the hobby is, IMO, one of the strongest arguments for brewing with RO.

 

[opercularia]

In my province, all routine historical test values are available over the internet. Perusing them quickly showed the variability of our water and convinced me that RO was my only choice.

Some water supplies are very stable, but only historical records over a period of years will tell you that.

 

[SoCal-Doug]

Not totally a waste of time. The results you receive will be valid for the water you sampled. You will know how to adjust it (or if it's possible for the style you want to brew). The problem is that in most areas, the water is going to change over time. Municipal water sourced dont stay consistent throughout the year. Any change in rain, lack of, or blending by the water management company/agency, will change your water chemistry.

On the other hand, if you start with RO water at 25 or 30 cents a gallon, spend a few bucks in a few jars of chemicals, you will always have a consistent profile by starting at zero and modifying it for what you need. You also wont have to deal with chlorine, chloramine, fluoride, and whatever else they add to it so they can turn turd water into drinking water.

 

[opercularia]

turd water into drinking water

Are you really trying to scare him?

 

[SoCal-Doug]

Nay. Not all regions convert turds into water. But I hear the turd regions make the best hazy's and juicy's

 

[mabrungard]

It can be a waste of time if your water supply quality varies significantly. This can be especially true for people living where they have reservoir and groundwater sources. The water quality can vary significantly between those sources.

For those of us with a single source such as wells, then it can definitely be worthwhile to find out if your water quality is usable for brewing. There may be no need to pay for a RO source if your water is suited for the main styles you brew. Having those test results is a good way to figure that out.

 

[rjs3273]

That's why I bought a reverse osmosis system and haven't looked back.

I just had a look around and they are not nearly as expensive as I had imagined. Running costs look manageable. Given how it works, am I right that there is always a considerable stream of waste water that often even exceeds the cleaned water?

 

[rjs3273]

I'd say (I don't have the data here) that it is probably more like 60 - 110.

So you are seeing up to a factor of two on your well water. That's useful. Thanks for the feedback.

 

[rjs3273]

Are you really trying to scare him?

Well, it works for them on the ISS!

 

[mongoose33]

My community's water is drawn from an 1100-foot-deep well system. I had the water tested in February of 2016, and among other things, TDS was 350.

I had it tested again in August 2018, 2.5 years later, to see if it was still the same. It was very close:

Not enough to worry about in my case, though I adjusted the water calculators slightly to account for the difference.

In OP's case, there's no point in getting a water report if it varies that much. My water's pretty alkaline, so suitable for mostly very dark beers without cutting w/ RO. I typically use a gallon of my tap water and the rest is RO water.

 

[ajdelange]

For those of us with a single source such as wells, then it can definitely be worthwhile to find out if your water quality is usable for brewing. There may be no need to pay for a RO source if your water is suited for the main styles you brew. Having those test results is a good way to figure that out.

So you are seeing up to a factor of two on your well water. That's useful. Thanks for the feedback.

As posted earlier and reconfirmed here, yes, there can be considerable variation in ion content from wells as well. But, doubtless, some wells are more stable than others.

One way around variation in alkalinity at least is the Zero Effective Alkalinity Method (see Sticky in this forum). Note that it is equivalent to measuring the alkalinity each time you brew and adjusting the treatment for the variations except that you don't actually explicitly measure the alkalinity.

Given how it works, am I right that there is always a considerable stream of waste water that often even exceeds the cleaned water?

Not always. The small systems bought at home improvement stores often have recoveries less than 20% but it is possible to have recoveries up to about 70% but such high recoveries are usually only found in larger systems. A home brewer can put together a system that recovers 33 to 50% of the feed water as RO.

 

[rjs3273]

I had it tested again in August 2018, 2.5 years later, to see if it was still the same. It was very close:

Those are really nice data. Thanks for posting.

 

[mongoose33]

Those are really nice data. Thanks for posting.

Pretty consistent, but the water 1100 feet underground isn't changing much year to year.

Dubuque, which is about 20 miles southwest of my location, is reputed to have great brewing water. They also draw from wells--I thought they got their water from the Mississippi--but some are deep like ours, and some are only 200 feet deep.

I've heard of brewers who lived in Dubuque but moved out of the city, and their beer turned south. They go to Dubuque now just to get some water.

As for me, it's mostly RO water.

 

[rjs3273]

Thanks to everyone for your input. It has been enlightening.

My main conclusions are
* Few people have actively monitored their water over an extended period to quantify the changes. I am not sure if I should be proud of myself or embarrassed?
* Single source supplies, particularly deep wells, tend to be reasonably stable
* Very many, but not all, municipal supplies use multiple water sources and then indeed a one-off test on its own verges on meaningless.
* If you are really worried, either test every time or use reverse osmosis / distilled water.

When I first started brewing a few years ago, discussion fora, books, magazine articles, everything I read extolled the virtues of getting a water profile test done and how important it was. I was dubious for the reasons everyone has discussed here and that is what started me on running this experiment to test it for myself. Now in this thread every response I get was, "Yeah, water varies all the time. Everyone knows it". I cannot think of a single beginners' guide to water chemistry I read that said that. I am sure they are out there and I just read all the wrong articles, but it was not at all the impression I got from fairly extensive reading as a novice brewer a few years back.

 

[mabrungard]

Now in this thread every response I get was, "Yeah, water varies all the time. Everyone knows it". I cannot think of a single beginners' guide to water chemistry I read that said that. I am sure they are out there and I just read all the wrong articles, but it was not at all the impression I got from fairly extensive reading as a novice brewer a few years back.

Surface water sources can vary. However a true groundwater source will not vary much. The exception is when a groundwater aquifer is in close proximity to surface water. For example, some municipalities place their wellfields in buried riverine deposits that are also alongside a river and the amount of water that they extract from the wellfield means that the incoming water is essentially filtered river water. Yes, that 'groundwater' quality will vary.

 

[ScrewyBrewer]

RO water is the way to go for me. Shopping for distilled water and lugging it home is a PITA stop gap until you install an RO filter at home. But both approaches eliminate the guesswork and complexities inherent to tap water and deciphering reports. Unless your brewing much larger than 'homebrewer sized' batches or cost becomes an issue.

 

[ajdelange]

Well water does vary. At least mine does. The simplest way around all this is, as has been mentioned by several people several time, is to move to RO. But even if you get an RO system you will need to know what you are feeding it and the way to know that is with a water test so the answer to the question posed originally is no, getting a water test is not a waste of time.

With water test results in hand it is still, whether feeding an RO system or brewing with the water, helpful to know how variable it is. This is, fortunately, very easy to determine. The most important water parameter to a brewer is alkalinity. Alkalinity is doubtless the easiest to measure. You drop acid in the water until the pH reaches 4.5. That's all there is too it. Several manufacturers make simple, inexpensive kits which let you do this. The best ones come from Hach but, as you can probably guess, best means more expensive (aroun $50 for 100 tests). Cheaper ones can be had from aquarium (Salifert $16) or you can put together something together yourself.

Note that if you detect a change in alkalinity there has been an equivalent (equivalent in the chemical sense) change in something else. For example if the alkalinity goes down 1 mEq/L (50 ppm as CaCO3) then the sum of the sodium, potassium, calcium and magnesium ion contents has also gone down by that much (unless chloride or sulfate has gone up at the same time).

 

[SoCal-Doug]

It's not just well water that changes. Some areas (mine definitely) can switch sources on the fly based on municipal contractual needs. My stupid city has to list four different sources on the city annual report and adds a statement that says something like "we switch and/or mix sources to different areas, lab results for your area are not guaranteed".

The only guarantee I have for known water is to start with RO and adjust as needed.

 

[sillbeer]

I have three 5 gallon bottles I fill up at my local grocery store for .41 cents per gallon. I top the remaining 5 gallons of water off with my house water pushed through a charcoal filter. I had the water tested a couple years and compared it to my neighbors results. He had his water tested two years before me and our numbers were almost identical. I feel fairly confident our water is stable but I have to use a lot of lactic acid to get my Ph within the proper range so I just use store bought water for the most part and add a couple ounces of acid malt.

I'm lazy. The shopping carts at Smiths only hold three 5 gallon bottles. I would probably go 100% store bought water if the cart held four.

 

[ScrewyBrewer]

@ajdelange the total dissolved solids in the tap water feeding my RO filter are very low. I doubt the accuracy of my water utility’s reports or how recently they’ve been updated. So short of sending a sample out to Wards a TDS reading of the tap water can provide a pretty good indication of its alkalinity.

 

[rjs3273]

Most of the time my water is coming from Hetch Hetchy and there is very little of anything in it (see links in my original post) apart from all that nasty chloramine. RO is the obvious solution but truth be told I am probably quite happy that it varies occasionally. Testing it on brew day (alkalinity drop count test and EDTA titration as described by ajdelange) is all part of the ritual, makes me feel useful and gives me cool looking plots.

 

[Blazinlow86]

RO water is the way to go for me. Shopping for distilled water and lugging it home is a PITA stop gap until you install an RO filter at home. But both approaches eliminate the guesswork and complexities inherent to tap water and deciphering reports. Unless your brewing much larger than 'homebrewer sized' batches or cost becomes an issue.

Even at homebrewer sized batches I'm thankfull to have basically ro out of the tap. If I had to lug 6+ of those 5 gallon jugs from the store every brew day I woulda given up long ago lol Cheers

 

[ajdelange]

@ajdelange the total dissolved solids in the tap water feeding my RO filter are very low. I doubt the accuracy of my water utility’s reports or how recently they’ve been updated. So short of sending a sample out to Wards a TDS reading of the tap water can provide a pretty good indication of its alkalinity.

Good point. Much simpler and cheaper than an alkalinity test too. This suggests that when you send your sample off to the lab you be sure to check its TDS.

Of course if you are planning to brew with the water you may want to know its alkalinity in order to calculate acid additions. OTOH you can use the Zero Effective Alkalinity Method. You don't need to know the alkalinity for that.