Skip Ribbon Commands
Skip to main content


The City of Barrie's Wastewater Treatment Section consists of six major pumping stations and one state-of-the-art Water Pollution Control Centre. Treating wastewater is a process of cleaning it to remove solids, chemicals and other undesirable material before it is pumped to Lake Simcoe. The City maintains very high standards in wastewater treatment to ensure there is minimum effect on Lake Simcoe. An in-house laboratory constantly monitors all processes within the Water Pollution Control Centre to ensure our high standards are being maintained.

What is Wastewater?

Wastewater is the mixture of liquid and solid materials that residents and businesses flush down toilets and empty down sinks and drains. This material is directed to the plant through a network of pipes that make up the city’s sanitary sewer system to the wastewater treatment plant. 

Why Do We Want to Treat Wastewater?

Treatment of wastewater is an essential process that prevents contamination and the destruction of our waterways, drinking water resources and natural water resources.  Wastewater is approximately ninety-nine percent water and only one percent solids. The removal of these solids and disinfection of the water before discharge is the basic concept of wastewater treatment.

If wastewater was discharged without treatment directly to a receiving water system, such as Kempenfelt Bay, it would severely damage the water quality and render it unsuitable for swimming, fishing and other recreational activities.

Wastewater is a carrier of harmful bacteria and micro-organisms known as pathogens.  Several pathogens include Cryptosporidium, Salmonella, Typhoid, E-Coli, Hepatitis A & B and Giardiasis also known as “beaver fever”.

Wastewater is also rich in nitrogen and phosphorus nutrients which stimulate excessive aquatic growth, which in turn, can be detrimental to aquatic life such as fish and waterfowl.

How Do We Evaluate Wastewater?

Wastewater can be measured and evaluated in many different ways. Physical characteristics such as colour, odour and temperature are perhaps the most obvious to us. Two of the most important measurements that have a wide application in wastewater treatment are Suspended Solids and Biological Oxygen Demand. Suspended solids refer to un-dissolved articulate matter which may be filtered from the liquid portion. Wastewater containing excessive amounts of suspended solids can cause turbidity providing protection for pathogens to live or blanketing of the lake bottom and, in turn, destroying spawning beds for aquatic life.  Biochemical Oxygen Demand, or B.O.D., represents the quantity of oxygen utilized in the stabilization of wastewater under controlled laboratory conditions. High values are indicative of the capacity of wastewater to cause rapid depletion of this dissolved oxygen content of a receiving body of water, rendering it incapable of sustaining higher life forms.

Frequently Asked Questions
What is the Flare coming from the stack at the WwTF?

Excess bio gas (a natural bi-product of sewage treatment) is being burnt off. This is a normal process at the WwTF.


Looks like your screen is a bit too small

The page you are attempting to view is not currently compatible with the dimensions of your device. Please visit this page on a larger screen.