Wastewater Treatment and Biosolids Management Master Plan

Thank you for sharing your feedback. We are happy to report that we are already doing this. In 2019, 100 per cent of biosolids (3,700 tonnes) were treated using the Lystek process and beneficially reused by farmers as fertilizer. In addition, we partially power the Wastewater Treatment Plant using captured digester gas generated by the wastewater treatment process.

Thank you for your question. While this may be up for consideration in future Master Planning, at this time it is not necessary based on the City future population projections from the Province. Additionally, our wastewater treatment plant currently has space to expand on Guelph's projected population growth.

If we identify this as a future need, we would need to take into consideration things like: associated expenses that come with building, operating and maintaining a second wastewater treatment plant versus expanding the existing plant. We also need to consider the environmental impacts and the capacity of the Speed River.

A big function of the Master Plan is getting an understanding of how our population growth will impact our natural environment, like the capacity of the Speed River. Through the Master Plan we will also review treatment processes that will address contaminants, including things like chemicals and medications.

The City is undertaking an assimilative capacity study of the Speed River downstream of the WWTP, which will ensure that the increase in flows resulting from population growth will not have a negative impact on the Speed River. It will determine the loading rates of various constituents that the Speed River can assimilate, which will determine the treatment requirements required for the Master Plan such that the natural environment is not negatively impacted.

Currently, the Town of Rockwood is allocated a maximum flow of 1,710 m³/day to the Guelph WWTP under its agreement with the City. This has been factored into the Master Plan’s future projections, so there are no concerns that flows from Rockwood will become an issue in the future.

We are aware that odours occur occasionally, and we understand your concern. We want you to know that we document odours and are evaluating this regularly.

Part of the Master Plan will provide us with recommendations for managing odours from the WWTP, including evaluating new technologies and an implementation plan that will ensure we are prepared to handle odours as our community grows.

The Master Plan will contain an implementation plan to ensure that the necessary upgrades will be completed to keep up with the population growth in Guelph into 2051.

Cost is one of the evaluation criteria for technology alternatives. Currently, development is charged to future homes and condos, although this Master Plan is not involved in evaluating funding sources.

The City has noted your recommendation and will be considered for future surveys.

The per capita flow rate is based on the previous 10 years of flow and population data in the City. While it is likely this is a conservative estimate, it is difficult to estimate future reductions in water usage due to the lack of data and information about future developments.

This per capita flow rate also includes flows from industrial, commercial and institutional users, such as the University of Guelph. Also, the capacity of many processes is based on loading rates rather than hydraulics. While the per capita flow rate may be reduced over time, the loadings will likely stay the same, resulting in a higher strength influent wastewater. The per capita flow rate may be a driver for some hydraulic upgrades later in the planning period.

Should the City’s per capita flow rate decrease, the consequence would be that capital expenditures would be delayed. This is a low-risk consequence. Should the City’s per capita flow rates increase above the projected value, the consequence is an earlier than expected capital expenditure, which is higher risk to the City.

The approach used is conservative while seeing that solutions will address future loading needs. Master Plans are updated on a 5 to 10 year basis, which will allow the City to adjust and address changes in the City’s per capita flow rate in the future.

Regarding the must-meet criteria, “proven in North America” was selected to ensure that the technology vendors have a presence in this region should service and/or consumables be required. For the various technologies, if it was proven in Europe or elsewhere in the world, only one full-scale installation was required in North America to meet the must-meet criteria. This way, the City will have captured technologies that are proven worldwide and ensured that there is reliable supply and service for the technology in North America.

A big function of the Master Plan is getting an understanding of how our population growth will impact our natural environment, like the capacity of the Speed River.

The City is undertaking an assimilative capacity study of the Speed River downstream of the WWTP, which will ensure that the increase in flows resulting from population growth will not have a negative impact on the Speed River. It will determine the loading rates of various constituents that the Speed River can assimilate, which will determine the treatment requirements required for the Master Plan such that the natural environment is not negatively impacted.

Thank you for the feedback. This idea will be considered when determining the City’s future outreach strategy.

The City is undertaking an assimilative capacity study of the Speed River downstream of the WWTP, which will ensure that the increase in flows resulting from population growth will not have a negative impact on the Speed River. It will determine the loading rates of various constituents that the Speed River can assimilate, which will determine the treatment requirements required for the Master Plan such that the natural environment is not negatively impacted.

Thank you for your feedback. We'll keep this in mind when communicating with the community

In the assessment of the assimilative capacity study of the Speed River downstream of the Guelph WWTP, the City will not be utilizing a dilution approach to determine the effluent limits for the WWTP. Rather we will be determining effluent concentrations that will result in improved downstream water quality from current Environmental Compliance Approval (ECA) conditions under low and moderate flow conditions.