This data comes directly off EPCOR's computerized water quality monitoring system and has not been validated. Please use it as a guideline only. For verified monthly data see the list of downloadable reports.
Note: All results are daily averages leaving the water treatment plants. The numbers in the distribution system may vary because of detention time and mixing in the system, and a slow decrease of the chloramine residual.
- Supply Zone
E.L. Smith primarily supplies the Northwest, West and Southwest and University area Rossdale primarily supplies the Downtown, East, Northeast and Southeast areas. However, depending on daily pumping and demand variations there is a large crossover region where water can be supplied from either plant at any time.
Water hardness is the result of dissolved minerals, usually calcium and magnesium. The North Saskatchewan River picks up these minerals as it flows over limestone rock. The North Saskatchewan River water is moderately hard, about 165 milligrams of calcium carbonate per litre (165 mg/L) on average. There are no health effects associated with calcium and magnesium minerals so there are no drinking water guidelines established for hardness.
One of the main objectives in controlling pH is to produce water that minimizes pipe corrosion or hardness scale build up. Pipe corrosion may become significant in our water at pH levels below 7.5, and scaling problems increase at above pH 8.5. As a comparison, soft drinks have a pH of 3 and drugstore antacids have a pH of 10. EPCOR's water has a yearly average pH of 7.8.
- Chlorine, (Total Residual)
In EPCOR's distribution system, the total residual chlorine is composed entirely of chloramine. Chloramine is a disinfectant that results when chlorine is combined with ammonia. It is a much weaker disinfectant than free chlorine but it stays in water longer, is more stable in distribution systems, and can more effectively penetrate any film or deposit on a pipe to kill bacteria. Our approval sets limits of 0.5 - 2.5 mg/L for drinking water. EPCOR's treated water contains an average of 2.19 mg/L.
- Alkalinity (mg/L)
Alkalinity in water is primarily a measure of the carbonate and bicarbonate ions dissolved from minerals in the rock that the water passes over. In our water, at pH levels of 7-8, it is almost all bicarbonate ions. Bicarbonate is not a regulated parameter and is not a health concern. At high levels, alkalinity can combine with calcium hardness to produce deposits of calcium carbonate. Moderate levels of alkalinity help minimize corrosion (very low alkalinity water tend to be more corrosive).
- Conductivity (µS/cm)
Conductivity is a measure of the ability of ions in water to carry an electric current. Conductivity is a good measure of the total amount of salts in solution (e.g., calcium, magnesium, sodium, potassium, carbonate, bicarbonate, sulphate, chloride, nitrate, and others). During spring runoff, conductivity will generally increase because of road salt being washed into the water. The conductivity of EPCOR's water averages about 350 µS/cm.
- Caustic Soda Dose (mg/L)
Caustic soda (NaOH) is added to the water to raise the pH to its required level to minimize pipe corrosion or hardness scale build up. Sodium makes up 0.58 mg/L of every 1 mg/L of caustic soda added to the water. The raw water has an average sodium level of 5 mg/L that varies from 3 - 8 mg/L (2000 data) but can be a bit higher on a few days a year when street runoff contains more salt. Therefore an estimate of the treated water sodium level would be [5 mg/L + caustic soda dose * 0.58]. Using this estimate, a caustic soda dose of 25 mg/L would result in a treated water sodium level of 20 mg/L. The aesthetic objective for sodium in drinking water is less than or equal to 200 mg/L while for those on sodium restricted diets it is recommended to have less than 20 mg/L in the water.