Toronto Water

Before 1842, Toronto's water supply was manually pumped from Lake Ontario, streams and wells.

Water carters would take the water and distribute it to customers across the city.[2]

From 1843 to 1873, water was privately provided by Furniss Works or Toronto Water Works, a subsidiary of Toronto Gas Light and Water Company, which was owned by Montreal businessman Albert Furniss.[3]

Following Furniss's death in 1872, the City of Toronto bought out Furniss Works and transformed the water supply to public hands under the Toronto Water Works Commission.[4]

Outside of the pre-amalgamation City of Toronto each of the former municipalities had their own treatment plants and pumping stations:

• North York
  • Oriole 1923 - ruins of pumping station found near Duncan Mills Road and Don Mills Road[5]
  • Steeles 1930s
  • Sheppard West 1940s
• Scarborough 1921
• New Toronto 1924

Prior to the 1950s, the municipalities were responsible for water treatment and water came from local water sources like wells and streams.

The current system was introduced in the mid-1950s, with the formation of Metro Toronto in 1954, and was managed by Metro Toronto. Following amalgamation in 1998, Toronto Water was created from the Toronto Works and Emergency Services and once part of Metro Toronto Works department. Since 1975, Toronto has supplied water to York Region (mostly to residents in the south end of York).[6]

Water pumped from Lake Ontario is treated via conventional drinking water treatment processes:[7]

1. Pre-Chlorination
2. Flocculation and Sedimentation
3. Filtration
4. Chlorination
5. Chloramination, prior to distribution

The City of Toronto uses four water treatment plants:

• R.C. Harris Treatment Plant [8]
  • Queen Street East and Victoria Park Ave.
  • Capacity of 950 megalitres per day
• Island Treatment Plant [9]
  • Located on Centre Island
  • Capacity of 410 ML/d
• F. J. Horgan Treatment Plant (formerly Easterly) [10]
  • Copperfield Road
  • Capacity of 487 ML/d
• R.L. Clark Treatment Plant (formerly Westerly) [11]
  • 23rd Street in Etobicoke
  • Capacity of 557 ML/d
  • Opened in 1968 replacing the New Toronto Filtration Plant (opened 1915 at Lake Shore Boulevard and Seventh Street and which became Lakeshore Pumping Station 1968-2000)[12]

The drinking water distribution system operated by Toronto Water comprises 6 pressure zones and approximately 520 km of watermains (greater than 150 mm in diameter) [13]

Pumping stations are located across the city to pump water from the filtration plants to residences. They are particularly critical since the city gains in elevation as it moves northwards away from Lake Ontario. Some pumping stations are located outside the city.

There are two pumping stations located outside of the city limits and part of the water service provided to York Region by Toronto:

Toronto water stores water in three formats:

• Floating Reservoir: newer Water tower or older Water tank with limited capacity
• Ground level Reservoir: underground water storage with grass covered top with large capacity
• Temporary storage: stored at a water treatment plant with limited capacity

Water in the city is stored once it is treated, ensuring uninterrupted water supply.

There are 5 water towers located in the city[15] and 1 outside the city. They are mainly located in areas that cannot accommodate underground reservoirs due to space restrictions.

There are 10 underground reservoirs across Toronto and in Markham:

There are in-plant temporary storage tanks storing water as well:[19]

In addition to water storage, the City has also constructed the following subterranean storm water detention tanks: