General Information

The mandate of the Water Pollution Control Facility is to ensure that the environment and public health are protected. If raw sewage were allowed to enter the ecosystem untreated, the resulting consumption of oxygen from the receiving waterway would leave insufficient levels of this life-sustaining gas for fish and other aquatic life to survive. Additionally, pathogenic microorganisms present in sewage would also enter the waterway, potentially causing outbreaks of disease.

To ensure the public health, the Town of Cobourg has constructed two Water Pollution Control Plants. WPCP #1 is located on the west shore of the Cobourg Creek, at the end of University Avenue. WPCP #2 is located at the east end of Town on the corner of Normar and Thompson Road.

Conventional Activated Sludge System

Both Sewage Treatment Plants in Cobourg are what is known as "Conventional Activated Sludge" plants.  This means that they employ live microorganisms (i.e. activated sludge) to break down the sewage.  A typical Conventional Activated Sludge Plant consists of a Primary Clarifier, Aerations Tanks, Secondary Clarifiers and a Chlorine Contact Chamber.

The activated sludge (also called Mixed Liquor) is a very concentrated mixture of microbes which, when supplied with oxygen, can break down complex organic material into smaller, simpler material that has less offensive odours and can be disposed of in a more environmentally friendly manner (e.g. land application).


Activated Sludge or "Mixed Liquor"



WPCP Environmental Objectives

How does a Wastewater Treatment Plant Work?

General Information for Septic Waste Haulers

Sewer-Related Bylaws


News & Information 

  • NOTICE OF COMPLETION - Cobourg WPCP No.2 Municipal Class Environmental Assessment
    To request a copy of the report or for the opportunity to provide comment please see the following link: Notice of Completion 
  • The full Envronmental Assessement Final Report can be downloaded here: EA Final Report