Did you know over 90 million liters of wastewater is treated every day
at Saskatoon’s Wastewater Treatment Plant?
That’s enough to fill 36 Olympic-sized swimming pools!
So what exactly is “wastewater”? Wastewater is any combination of water and
waste that is flushed down your toilet, sink or tub.
This wastewater eventually ends up in the South Saskatchewan River, but before it gets
there, it’s treated at the Wastewater Treatment Plant.
We use some of the most environmentally sustainable and up-to-date treatment processes at our
plant so that people, property and the environment are protected.
So how does wastewater get to the Wastewater Treatment Plant?
Wastewater flows from the sinks and toilets in homes and businesses, and from industries
in the community into a underground maze of pipes called the sanitary sewer system.
Saskatoon’s wastewater collection system is about 1,050 kilometers long, approximately
the distance to Edmonton and back!
A gravity system and 28 pump stations located throughout the city keep the wastewater moving.
Once the wastewater reaches the plant, an extensive and complex treatment process begins.
Over 200 pumps and mixers, and over 50 km of internal piping, enough to stretch around
Saskatoon’s Circle Drive twice, help the wastewater travel through the plant.
In the first stage in the treatment process, the wastewater passes through a series of
screens to remove materials larger than 12.5 mm. These materials are cleaned and transported
to the landfill. The wastewater then travels to large basins
where heavier materials, called sludge, settle and sink to the bottom. Lighter materials,
including fats and oils, called scum, float to the top.
The sludge and scum are sent to fermenters and digesters where bacteria breaks it down
further. During this process methane gas is produced,
enough to heat about 390 homes each year. We use this methane as fuel to heat the buildings
and certain processes at the wastewater treatment plant. Any excess methane is flared.
The sludge, about 5,600 tonnes per year, is pumped into storage cells and used as fertilizer
on nearby farmland. The remaining water from the primary sedimentation
basins is pumped to another process where nutrients like phosphorus and nitrogen are
removed using naturally occurring microorganisms. In 2013, Saskatoon became the first city in
Canada to recover this phosphorus and nitrogen and use it to create a product called Crystal Green ®
, an environmentally responsible and extremely efficient fertilizer.
Finally, the wastewater passes between ultraviolet lamps sterilizing any remaining microorganisms
such as Cryptosporidium, E coli and Giardia before the water is deposited back into the
South Saskatchewan River. Our treatment process ensures the final wastewater
does not harm our precious river and down-stream users
Back at the plant, all aspects of the treatment process are closely monitored twenty-four
hours a day, seven days a week, by highly trained plant operators.
Our on-site laboratory performs about 30,000 analyses each year to ensure continuous quality
control, record the plant’s performance, and monitor the environment.
We’re also prepared to expand our operations as our city continues to grow.
We have a 30 year, long-term capital development plan and the capacity to
ensure effective and efficient wastewater treatment for a population
of about half a million. Protecting people, property and the environment
-- these are the priorities of the Wastewater Treatment Plant.
For more details or to learn more about our environmental initiatives, visit Saskatoon.ca