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Kingston Biosolids and Biogas Master Plan

Kingston Biosolids and Biogas Master Plan

Project background

Utilities Kingston manages the water and wastewater infrastructure for the City of Kingston. Through long range planning and identification of operational efficiencies, customers are assured of safe, reliable services at a fair price. A holistic approach to managing the water supply and treatment ensures protection of this valuable resource, minimizes greenhouse gas emissions and protects the natural environment. 

The main processes used, at the Ravensview and Cataraqui Bay Wastewater Treatment Plants (WWTP), to clean waste water prior to discharge back to the environment are:

  • Screening and grit removal to take out untreatable materials;
  • Settling of organic solid materials;
  • Biological treatment to remove dissolved carbon and nutrients;
  • Disinfection and discharge.

The settled organic solid material and material from the biological treatment process are further stabilized in anaerobic digesters to reduce odour, pathogens and mass. Anaerobic digestion (AD) is a biochemical process where microorganisms convert organic compounds into methane and carbon dioxide. The end products of the AD process are the methane and carbon dioxide gases and a nutrient and carbon rich solid soil amendment that can be applied to farm fields as fertilizer.  The methane produced by the process is a potent greenhouse gas (GHG) which can either be flared to reduce its GHG potential or collected and further refined for use as a renewable natural gas or biogas fuel.

During planning and design of current upgrades for Cataraqui Bay WWTP, construction logistics and budget constraints resulted in upgrades to the solids treatment phase being deferred.

In 2015, Utilities Kingston undertook work to examine the feasibility of optimizing biogas production as part of the planned upgrade to the existing solids treatment process at the Cataraqui Bay WWTP. Using a holistic approach for both plants a range of options were examined to potentially increase biogas production and also decrease the residual biosolids. The increased biogas production was identified as a benefit in reducing GHG emissions which may qualify for funding through the then Cap and Trade regime being embarked upon by Ontario.

In order to comply with the Environmental Assessment Act, Utilities Kingston determined the best approach would be to undertake a Master Plan for biosolids and biogas. Through a qualification based request for proposal issued in 2017, TetraTech Canada Inc. was retained to undertake the project.

Exhibit 1 summarizes the work completed to date to assess potential sites at the WWTPs and the different technology options. During the detailed assessment, consideration was given to the inclusion of other organic material, such as the source separated organics (SSO) from the City of Kingston’s curbside Green Bin program to further increase gas production and address Ontario’s direction to reduce or eliminate organics sent to landfill.

Based on the work undertaken by TetraTech to date, the most feasible and beneficial scenario at this time is to upgrade the solids process at Cataraqui Bay WWTP, including the addition of other organic material, such as the organics from the City’s residential Green Bin program. Following input from public consultation and further discussions on potential use of the biogas, a preferred option will be provided.

The final phase of the project will include public consultation where Council, staff and the public will be invited to participate by providing comments on the proposed plan. The Master Plan will provide opportunities for actions to support Kingston’s Climate Emergency Declaration while addressing Council’s priorities to:

  •   Demonstrate leadership on climate action;
  •   Strengthen economic development opportunities; and
  •   Foster healthy citizens and vibrant spaces.

The Canadian Clean Fuel Standard, currently under development by the federal government, sets targets to reduce the carbon intensity of fuels, which is creating a market for clean biogas or renewable natural gas. As recommended in TetraTech’s Detailed Assessment Report, Utilities Kingston proposes to undertake early discussions with potential purchasers of the biogas, including determining the benefit to the City of Kingston’s natural gas system.

Services affected

  • Wastewater


The Master Plan project is conducted in accordance with the requirements for Phases 1 and 2 of the Municipal Class Environmental Assessment (EA) (October 2000, as amended in 2007 and 2011). Phase 1 of The Class EA process involves identification of the problem or opportunity to be addressed by the project. Phase 2 of the process identifies alternative solutions to addressing the goals of the project.  See more information on the Municipal Class Environmental Assessment.  One public information centre (open-house style) is to be conducted as part of this project, to be held in 2020.

Design and Construction

The Master Plan project provides a list of recommended infrastructure improvement projects including new facilities, upgraded infrastructure and operational changes required to support existing and future development in the City of Kingston.  Projects recommended by the Master Plan will each follow an individual Environmental Assessment approach as required by the Municipal Class Environmental Assessment process.  As such, this study itself does not have a design and construction phase associated with it. 

Schedule and Project Downloads


  1. Notice of Project Commencement: to be published in the Kingston Whig Standard in January 2020
  2. Public Information Centre: January 30, 2020. View the slides.
  3. Notice of Project Completion: August 25, 2020
  4. Final Report Documentation: Kingston Biosolids and Biogas Master Plan

Additional downloads

Kingston Biosolids and Biogas Master Plan

Information Report to the Environment, Infrastructure and Transportation Policies Committee Report Number EITP-19-011

TetraTech’s Preliminary Assessment Report

TetraTech’s Detailed Assessment Report


The project contacts are as follows: 

Utilities Kingston
Allen Lucas
Manager, Research and Projects
P.O. Box 790
Kingston, ON, K7L 4X7
Office: 613-546-1181, extension 2250
Tetra Tech Canada Inc.
Peter Klaassen
Vice President – Ontario Division - Solid Waste Management Practice

Office: 226-203-5209