Sign In


May 3 - 9, 2015 is WATER WEEK! Click here​ for ways to participate!

How Much Water is There?​


The Earth's surface consists of approximately 70% water! The oceans (salt water) account for 97.5% of this water, while the other 2.5% is considered freshwater. The 2.5% freshwater is found in glaciers(~30.9%), snow and ice (~68.7%), lakes and rivers (~0.4%). The diagram below illustrates the above percentages.

When you consider that 70% of the Earth's surface is water, only  approximately 0.01% of this water is readily available for use by humans! There is a lot of water available, but the vast majority of it is saline water (oceans), which is not fit for use. 

Where does our water come from?

The City of Lethbridge gets all of its water from the Oldman River. A river is considered a surface water supply. Lethbridge does not use groundwater from wells. Our Water Treatment Plant processes river water into safe, healthy drinking water.

Where is the Water Treatment Plant located?

The Plant site is on the east bank of the river, south of Whoop-Up Drive, and across the river from the University of Lethbridge. We process an average of about 53 million litres of high quality drinking water on a daily basis. The maximum daily production in 2013 was 95.3 million litres, on August 28th.

About the Water Treatment Plant in Lethbridge

The City of Lethbridge water distribution system consists of 570 km of water main and 6 storage reservoirs with pump stations. The water mains and pump stations deliver water to residences and businesses throughout the city and neighbouring communities.
The Water Treatment Plant draws our water supply from the Oldman River. The Plant is capable of treating 150-million litres of water per day and uses a multi-step treatment process.

How is the water treated so you can drink it?

1. Coagulation is the addition of approved water treatment chemicals to convert microscopic particles and other contaminants into larger and heavier particles

2. Sedimentation is a process that removes the majority of these larger particles by settling them in tanks called clarifiers

3. Filtration of the "settled" water removes most of the remaining particles to thousandths of a millimetre (too small to see)

4. Fluoridation  is the addition of fluoride ion to the water to benefit the community's dental health. Lethbridge has added fluoride to the water since 1974

5. Disinfection  of the water with chlorine is a way to protect public health from disease causing organisms that can be found in the river. The risk to public health is reduced further by treatment with ultraviolet (UV) light. Before the water leaves the treatment plant, we combine the chlorine with ammonia to form chloramine. This reduces the formation of disinfection by-products, and ensures a long-lasting "residual" to protect our water against bacteria or other organisms on its journey to your home tap.

Click here to find out how the Water Treatment Process works in Lethbridge!

How is the water tested to ensure its quality?

  • Daily water tests
  • Bacteria tests performed by the Provincial Public Health Laboratory each week
  • Monthly chemical analysis that includes metals and disinfection by-products
  • At least twice per year, treated water samples are subjected to a scan of 40 organic compounds, including pesticide chemicals, over 40 tests for metals, and other routine analysis.
  • Over 30,000 tests were conducted on our treated water in the year 2013
Click here to view the Water Consumer Confidence Reports from 2004 - 2013 for further information on how our drinking water is treated and tested.


**The City of Lethbridge meets or exceeds every provincial and national standard for clean water.


Find out how much water the average Lethbridge resident uses.



Quick Links!

Click on the links below to find out more about our drinking water.