Edmonton Water Chemistry Simplified
Edmonton is lucky in that we have Epcor who monitors many of the important ions that we need to consider while brewing. It is particularly well adapted for darker styles of beers because of its high carbonate content, which balances the acidity of dark malts. Brewing stouts, porters and browns in softer water tends to make them harshly acidic and unpleasant to drink. However, if you want to make more than that, you need to alter your water somewhat.
What you need to know
Unless you are buying expensive water testing equipment and testing your water at the moment before you use it, everything is an estimate; but we can get pretty good estimates with the data we have available. There are two places to get that data
The first link is the Daily Water Quality report which, for us, gives us an up to date reading of Total Hardness, pH and Alkalinity.
The second link is the monthly report which gives us the readings for chlorine, chloramine, sulphate, chloride and the ability to calculate the ratio of Total Hardness and Calcium Hardness.
With these two, we can get our key values that you want for any water calculation software.
Calcium – you need at least 50 ppm to allow your yeast to flocculate. Plzen is only 25 ppm and a true, unfiltered Czech Pilsner will be off-brilliant because of it. To get the Calcium value, take the Calcium Hardness and multiply by 0.4. For the values above, the Calcium content would be 41 ppm
Magnesium – Since Epcor does not list the Magnesium content, we have to subtract the Calcium hardness from the Total hardness. For our values, it is 158-104 = 54. We can’t know for certain that all of this leftover hardness is Magnesium Carbonate, but the values are going to be low enough that it doesn’t matter. You can also use the ratio to determine those values from the Daily Water Quality report. Multiply Total Hardness by 0.34 to get the value for Magnesium Hardness. With that value, divide by 4. For the values we have above, the Magnesium levels would be at 13.1.
Other values, such as pH, sulphate and chloride levels are listed directly as values on the readout.
Negating Chlorine and Chloramines.
Chlorine and Chloramines are both fairly low when they leave the water plant which means that they are even lower by the time they get to you. Spring runoff or an unusually high bacterial/algal contamination will mean that these levels will increase. You’ll see this reflected in the Total Chlorine Residual values. If the Chlorine or Chloramine levels rise beyond what you consider acceptable, adding a campden tablet or ½ tsp of Sodium Metabisulfate, to 5 gallons of water and leaving it out over night. If you do this, be sure to add 10 ppm/5 gal to your sulfate calculations.
There are plenty of resources to calculate acid additions. I’ve started recommending against using acid unless you have a high quality, dual (or more) calibration point pH meter. The reason being that while a pH of above 5.4 will start to reduce enzymatic activity and 5.2 is ideal for both alpha and beta amylase, a pH below 5.0 will denature your enzymes irreparably. If you accidentally add too much acid, you might as well restart your mash.
Even with a good pH meter, if you have access to Reverse Osmosis water, it’s much more beneficial to cut city water with RO water unless you are trying (for some reason) to get all of the hardness you can.
Edmonton Water is sufficient in calcium and sulfate. We have an excess of carbonates and a lack of chlorides. Brewing with these values will give you an excellent dry Irish Stout. Because Edmonton water is only sufficient in calcium, you have lots of room to adjust the water to suit your needs. If you want a maltier stout, I would suggest adding 4g of CaCl/10 gal to round out the mouthfeel. And if brewing a lighter style, I would also suggest adding 2g of gypsum/10 gal. This will give you a fairly even balance between sulfates and chlorides. Burtonizing salts (a mix of gypsum and MgSo4) also work well with Edmonton water if aiming for an English IPA.
Secondary water sources
For some styles, it’s not enough to simply add minerals. Edmonton’s water, while having some versatility, isn’t able to brew (well) styles with subtle flavours. That’s because carbonates will absorb the beta acids (flavour) and essential oils (aroma) in styles requiring a soft touch. Pilsner is the style that most frequently comes to mind since there should be a subtle balance of all of the elements and adding more hops later in the boil to compensate simply doesn’t work.
For that, it helps to cut your water with Reverse Osmosis. I would aim for a 70/30 split for light styles that require subtle flavours. Amber lagers or lagers that call for a “Munich Decarbonation” work well with a 50/50 split. Keep in mind that you will need to add gypsum and CaCl to add your flavour ions, but also Calcium since it will drop below acceptable brewing levels.
15 gal needed. Add 8g CaCl & 4g Gypsum
Calcium: 102 ppm Magnesium 13 ppm
Sodium: 10 ppm Sulfate: 109 ppm
Chloride 80 ppm Bicarbonate 143 ppm
Balance: Slightly bitter
12 gallons needed. Add 4g CaCl & 2g Gypsum
Calcium: 124 ppm Magnesium 13 ppm
Sodium 10 ppm Sulfate: 124 ppm
Chloride: 107 ppm Bicarbonate 143 ppm
10 gallons needed (70/30 Reverse Osmosis/Edmonton) Add 4g Calcium Chloride& 4g Gypsum
Calcium: 91 ppm Magnesium 4 ppm
Sodium 3 ppm Sulfate: 107 ppm
Chloride: 77 ppm Bicarbonate: 42 ppm
11 gallons needed (50/50 split Reverse Osmosis/Edmonton) Add 4g Calcium Chloride & 2g Gypsum.
Calcium 101 ppm Magnesium 6.5 ppm
Sodium 5 ppm Sulfate 90 ppm
Chloride 103 ppm Bicarbonate 71.5 ppm
Balance - Malty