Learn more about Calgary's drinking water, such as where does our drinking water come from, how is Calgary's water treated and tested, and what to look for in your drinking water. To find this information and more, click on the following topics:
We also invite you to read
The Water Report. The report highlights The City's actions to protect public health and our rivers. It includes everyday opportunities for Calgarians to help conserve and preserve our water resources.
Water Safety
1. Where does my water come from?
The Bow River supplies the Bearspaw Water Treatment Plant and the Elbow River flows into the Glenmore Reservoir, which is the source of water for the Glenmore Water Treatment Plant. The Bearspaw Plant primarily supplies water to the north sector of the city, while the Glenmore plant supplies the south. However, the water supply from the two plants is interconnected through large diameter transmission mains to ensure a reliable supply at all times. Learn more about Calgary's water supply.
2. Is our water safe?
Yes, Calgary's world class water treatment and testing facilities consistently provide Calgarians with clean, safe drinking water. The City of Calgary continues to meet and exceed all federal and provincial health-related standards and guidelines. The City continues to provide you with safe reliable drinking water at a higher quality that is normally required by these guidelines and standards.
3. How is Calgary's drinking water made safe from microbiological organisms such as E.coli, Giardia, and Cryptosporidium?
Calgary's water treatment facilities are designed to effectively deal with microbiological threats using a multiple barrier approach:
- At the beginning of the treatment process, water is first disinfected with chlorine to help inactivate harmful micro-organisms.
- Coagulant (a mixture of aluminum sulphate and ply aluminum chloride) is mixed with the water to help remove the fine particles that make the water cloudy (turbid). The coagulat makees the the particles and micro-organisms clump together and settle out of the water in the settling basin.
- The water then flows through fine filters made of sand, gravel and anthracite. These filters screen out remaining particles and help remove any micro-organisms that may be resistant to the disinfection process.
- Finally, chlorine is added to the finished water before it leaves the treatment plant. This keeps the water disinfected as it travels through the watermains to reach homes and businesses.
4. How is my drinking water tested?
Calgary's drinking water is tested every step of the way - from the source to our water treatment plants and to your home. The City of Calgary performs approximately 112,000 drinking water quality tests annually. The City's testing facilities maintain ISO 17025 accreditation status through the Canadian Association for Laboratory Accreditation Inc.
The City measures and tests approximately 150 parameters (a parameter is a substance that we sample and analyze for to ensure the quality of our drinking water. For example:
- Inorganic compounds – fluoride, hardness and metals
- Organic compounds – trihalomethanes and pesticides;
- Physical parameters – colour, pH, turbidity (cloudiness), temperature, and conductivity
- Microbiological parameters – bacteria and parasites.
Samples from the Bearspaw and Glenmore water treatment plants are collected and analyzed on an ongoing basis, seven days a week. Additional samples are taken and analyzed within the distribution system at approximately 68 locations across Calgary.
5. My drinking water has an unusual taste or odor. Is it safe to drink?
Yes, your water is safe to drink. Unusual tastes and odours are 'aesthetic' in nature and do not pose a health risk.
6. Watermain repairs just took place on my street - Is my drinking water okay?
Before water service to your home is restored, The City thoroughly flushes the water main then takes and tests water samples to ensure the high quality of water once the work is completed. While it is unlikely that some sediment from pipes may be in your home's system, we recommend you do the following to remove it:
- Run water for 20 minutes through your cold water taps, including in the basement.
- Wash tap aerators and screens in hot soapy water; then, disinfect them for 10 minutes in a solution of one part bleach to nine parts water.
- Disinfect any water filters to the manufacturer's recommendations.
Water quality
1. Is Calgary's water hard?
Water from the Bow and Elbow rivers is considered 'hard' because of the amount of calcium and magnesium in the water. Hard water can cause build up on your water heaters and household plumbing. Read Water Hardness FAQs to learn more.
2. What causes unusual tastes or odours in my water?
Calgary's water undergoes rigorous testing to detect organic and inorganic substances that occur naturally in our watersheds and river systems. When drinking water reaches your home, it is largely free of any taste or odours.
However, our rivers and reservoirs are living environments. Changing seasons can pose challenges, such as cloudy water due to spring runoff or algae growth in warm weather. These can occasionally give our water temporary earthy or musty flavours or odours.
Taste and odour episodes are not typical, but they can arise from a number of factors including seasonal fluctuations of algae in the drinking water source, changes in the pH balance of water (particularly during run-off) as well as changes in chlorine concentrations in the water.
3. How does The City prevent tastes and odours in my water?
A new powered activated carbon (PAC) system at the Glenmore Water Treatment plant aids in the reduction of unusual tastes and odours such as earthy/musty taste and odour when they occur. The taste and odour compounds can be adsorbed onto PAC and removed. The Water Quality Laboratory also continually monitors and identifies the compounds that could potentially cause such events.
4. Where can I learn more about water quality?
5. Is fluoride added to Calgary's water?
The City's Water Services discontinued the practice of fluoridating Calgary's drinking water on Thursday, May 19, 2011. This is following direction from Council and Alberta Environment's authorization to amend The City's Operating Approval.
Fluoride naturally occurs in the Bow and Elbow Rivers, in concentrations varying throughout the year, between 0.1 and 0.4 mg/L. Water services continuously monitors the quality of water in its watersheds and drinking water, and make those results public in its annual Water Quality Report.
Drinking water in my home
1. Why does my water have a chlorine taste and smell?
The City of Calgary adds chlorine to disinfect your water and keep it free from harmful microorganisms. Some conditions, such as spring runoff, affect the quality of the water supply entering Calgary from the Bow and Elbow Rivers. During these times, we adjust water treatment, which may include increasing the level of disinfectant, to ensure that your drinking water remains safe. Therefore, you may occasionally notice an increase in the taste and smell of chlorine in your drinking water.
If you would like to remove the taste and smell of chlorine, fill a container of water and keep it in the fridge for drinking. Much of the chlorine will dissipate from the water overnight. You will also conserve water as you don't have to run the tap until the water feels cold every time you fill a glass.
2. Why does my water have a milky or cloudy appearance?
Air bubbles in the water may cause a milky or cloudy appearance. This is especially true in cold water. These bubbles pose no health risk. Cloudiness appears more often in the winter when the water is cold. If the water is allowed to sit, the air will dissipate and the water will clear.
3. Why is my water a yellow or rusty colour?
Watermain repairs, construction and other maintenance work in your area can cause some rust and sediment, which normally adhere to the inside of the water main, to break away. Fire hydrant flushing can also cause this inconvenience.
Learn more aboutwatermain flushing. The discoloured water is safe to drink, but may cause water to appear dirty. If this condition occurs in your system, allow a cold water tap to run for five to ten minutes to flush your pipes. If the condition persists, contact 3-1-1.
4. How can I ensure drinking water quality?
Yes, homeowners have a responsibility too. Homeowners must ensure no cross connections exist on their property that can contaminate their home's water supply. A cross connection is an actual or potential connection between the water supply and any source of pollution or contaminant.
5. My water smells musty at one faucet?
If the musty odors occurs only at one faucet, the odor is related to something at or near the faucet. Try cleaning the drain, this often removes the odors.
6. Why does my water taste stale?
Drinking water may taste stale if faucets have not been used in awhile. Run the water briefly to allow fresh water from the watermain in the street into your plumbing. If you have any concerns about the quality of your water, please contact 3-1-1.
