Mineral composition in tap water is variable over time. I’m curious how frequently people tend to have their tap water tested and what normally triggers this.
Last time I sent a sample to Ward Labs was in early October last year while in a severe drought. I’m thinking about doing another test now.
If Martin happens to read this – any advice? is there an optimal time to have your water tested if you only want to do it 1-2 times per year?
Well, the components you are most interested in are Alkalinity and Hardness. The rest of the flavor ions are inconsequential to mash performance, but could obviously affect flavor. Having those flavor ions fluctuate by 10 or 20 ppm would probably not affect flavor too much, so I am less concerned about them. I also find that variation in all the typical water ions are somewhat cyclical. Since you’ve tested in a drought, it appears appropriate to test again in non-drought conditions. The winter can be plenty wet. However the application of de-icing salts can affect water quality in lakes and streams. It might be worthwhile to see what that water supply quality is. Later this spring when the de-icing salts and snow melt have been flushed from the system, might also be a good time to test.
Now back to the alk and hardness. There are inexpensive aquarium test kits that can provide a quick look into how your water is doing NOW. That can be helpful in deciphering if adjustments to your water report inputs are needed. There is a conversion tool in Bru’n Water to convert values like KH (aka: alkalinity) and GH (aka: hardness). If you test via the test kits at the same time you send a sample off to a testing lab, then that will help assess how the aquarium kits report in comparison to a more comprehensive (and hopefully more accurate) lab test.
Are you public water or well.
I was really surprised when I tested my well water about 9 months apart how similar it was in spite of a drought in the middle.
Thanks Martin! The drought has lasted through the winter also. We’ve only had ~6 inches of precipitation from October through February. Much lower than “normal.” Now that I think of it, I believe our annual city water report should be coming out in Mar/Apr. I am curious how the Ward data would compare. But as you suggest, I will probably wait until April/May. Hopefully we get several inches of rain between now and then.
Looking at the city water report data from 2008-2012, everything except Magnesium has been wildly variable. Here are some min and max examples:
Sulfate - 64 - 110
Chloride - 39 - 95
Bicarbonate - 39 - 171
Hardness - 140 - 200
Alkalinity 78 - 141
Just for fun since it’s a major player in flavor according to Palmer, the min and max for sulfate:chloride ratio is 1.01 (96:95 Oct 2012) and 1.8 (96:53 Spring 2011).
[quote=“560sdl”]Are you public water or well.
I was really surprised when I tested my well water about 9 months apart how similar it was in spite of a drought in the middle.[/quote]
Public. The main source for our water is the Kansas River.
