Toronto’s water supply primarily comes from Lake Ontario, processed through four main treatment facilities: RC Harris in Scarborough, RL Clark in South Etobicoke, FJ Horgan in the east end of York, and Island on Centre Island.
There are four water treatment plans that take raw water from Lake Ontario and convert it into safe potable water.
The last water treatment facility is named Island, located on Centre Island.
The third water treatment facility is FJ Horgan, located on the east end and region of York.
The next water treatment facility is RL Clark, located in South Etobicoke.
The first water treatment facility is RC Harris, located in Scarborough.
The water for the city comes from Lake Ontario, and only Lake Ontario.
Interesting facts on the city's water supply
Everyday, the city of Toronto treats more than 1 billion litres of safe drinking water a day at four different water treatment plants.
Every year, water treatment plants conduct over 20,000 tests to ensure the water is safe and drinkable.
As well, the Toronto water lab conducts 15,000 bacteriological tests on samples collected from the water distribution system annually.
There are 11 huge underground reservoirs that are used to maintain pressure and supply for peak periods and emergencies such as fires.
There are many threats to the water supply of the city of Toronto.
One of the threats to the City of Toronto water supply is water pollution.
Lastly, when polluted groundwater reaches drinking water systems, it can pose a big threat and water supply, as well as create public health threats.
It affects water supply because not all water can be made into drinking and potable water, as well, thee are not always facilities that clean water and make it drinkable, some people cannot afford it or can choose not to use it.
Water pollution is the contamination of water bodies usually caused by human activity.
How is the water treated?
Water is collected from Lake Ontario through intake pipes located deep below the lake, one to five kilometres from the shore.
Prior to distribution between homes and business, the following substances are added: chlorine, fluoride, ammonia and phosphoric acids. These are all to prevent and remove harmful toxins that are not cleared by the previous processes.
The lake water is passed through screens to remove large debris and then through filters to remove additional impurities. Water is disinfected using either chlorine or ozone. Aluminum Chloride is added to water to form a jelly substance called floc, joining large particles, which goes through additional filtration. The water travels though settling basins so larger particles settle to the bottom. The clear water at the top proceeds to filters containing gravel, sand and carbon to remove suspended impurities and bacteria.