High pH.

Hey dudes!

First post. 5th brew.

I haven't brewed in a while, thought I'd take up the hobby again. It tastes better than my other hobbies.

At any rate, I live in Austin, Texas and we have a unique H2O profile. The pH out of the tap is somewhere north of 10, maybe even 10.5. How might this negatively or positively affect the brews I make? Are there specific beers that could be heightened by the high alkalinity?

Thanks! Happy Brewing.

If you're just doing extract, it's no big deal. However, if you're planning to do any mashing with grain, you'll need to get that pH down to 5.5-6.0 in order to gain efficiency. Get some gypsum powder, your LHBS should have it.

It's doubtful that your water's pH is really that high. The EPA secondary limit is 8.5 and that is also the WHO's recommended maxiumum. The simplest water with that pH would be DI water with ~ 9 mg/L sodium hydroxide dissolved in it. This can apparently happen in areas where the water is contaminated by runoff from mines but no one would drink such water.

In any case it is not the pH of the water which is important but rather the alkalinity. Water of pH 10.5 has a minimum alkalinity of 13 ppm as CaCO3. This alone would not have much effect on beers made with it. A little more acid would be needed than if the beer were brewed with distilled water (alkalinity 2.5). There well may be other things (besides he 9 mg/L NaOH) dissolved in the water which would raise its alkalinity appreciably. This would have an impact. To comment in any fuller detail I'd need a full inorganic report on the water.

Thanks AJ and Mike.

here is a link to the city's water report. It says ~pH 9.7, but phenolphthalein trips to full purple at my tap, which I thought turned at 10.

We have large amounts of limestone throughout our recharge area, which I imagine explains the high pH. it also tastes great, btw :cross:

Unfortunately, Secondary Criteria are recommendations and are not enforced. While a municipal water pH of 10 is not a good thing for a number of operational issues, it is probably an anomoly unless the water is naturally low in calcium. A pH that high will cause scaling in the pipes. More likely is that they use a lime softening process and the recarbonation of the water is not working properly.

9.7 isn't a whole lot better than 10. Assuming the hardness is 60 ppm from calcium and 48 ppm from magnesium the saturation pH is 8.28. As 9.7 is appreciably higher than this there is a definite liklihood that mains will become obstructed over time. But that's not your problem (well, it is in that your taxes or bonds will go to pay for new mains and that, if you don't soften coming into your house, your house plumbing may eventually become obstructed).

Phenolpthalein turns from red to clear at pH 8.3 (it's used as the indicator in alkalinity titrations and the alkalinity measured to the point where it turns is called the "P alkalinity" because of this).

Wow, you guys know a lot about water! I would say your ph is that high because they want it that high or can't control it with recarbonating it after the softening process. I know we have to run our ph high, of course not that high (around 9.4),due to having a problem in our main storage tank during the summer months keeping our chlorine residuals up. I know this doesn't help any but thought I'd chime in.