German Mills Settlers Park Sanitary Infrastructure Protection Project

Toronto and Region Conservation Authority (TRCA) in partnership with the Regional Municipality of York (York Region) has proposed to undertake infrastructure protection works within German Mills Settlers Park in order to provide long-term protection to at-risk sanitary sewer infrastructure. 

Project Location

The German Mills Settlers Park Sanitary Protection Project is located along an estimated 260 metre stretch of German Mills Creek, located within the Don River watershed. The project area is within municipally owned property known as German Mills Settlers Park, situated west of Don Mills Road between John Street and Steeles Avenue East, in the City of Markham. A 750 mm diameter sanitary line and public trail run parallel to the east bank of the watercourse from John Street to the southern limits of the park. Within certain locations of the proposed project area, the sanitary line crosses the watercourse as shown in Figure 1 below.

Figure 1. Project location mapping with work area highlighted in by red polygon. TRCA, 2018.
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Project Background

In 2011, TRCA in association with York Region, developed the Infrastructure Hazard Monitoring Program (IHMP). The purpose of the IHMP is to ensure timely identification of risk to infrastructure due to watercourse activity (i.e. channel migration, widening, etc.) and efficient prioritization and mitigation of such risks in collaboration with stakeholders. The IHMP broadly divides watercourse erosion risks into two types of sites: intersection sites to assess the risk of bed erosion where the sewer crosses a watercourse, and proximity sites to assess the risk of bank erosion and lateral channel adjustments in close vicinity to the infrastructure. Intersection sites are categorized using an “I-” identifier, while proximity sites are categorized using a “P-” identifier.

The 750mm diameter sanitary main was installed within German Mills Settlers Park in 1970. Over the past 48 years, German Mills Creek has naturally migrated within the floodplain and has shifted over or in close proximity to the sanitary main or associated maintenance chambers. As a result, the watercourse is now at risk of exposing the sanitary infrastructure at six distinct locations within German Mills Settlers Park. Three alternative solutions have been proposed to protect sanitary infrastructure. As such, a Schedule B Municipal Class Environmental Assessment for Water and Wastewater Projects is being utilized as part of the planning and design process for this project.

Figure 2. Manhole and erosion at Site 2 (I-152). TRCA is planning emergency maintenance interim sanitary protection works for I-152 this fall 2018. TRCA, 2018.
Existing conditions at P-060, facing downstream. TRCA, 2017.
Figure 3. Existing conditions at P-060, facing downstream. TRCA, 2017.
Existing conditions at P-068 facing downstream of pedestrian bridge. TRCA, 2017.
Figure 4. Existing conditions at P-068 facing downstream of pedestrian bridge. TRCA, 2017.
Schedule B Municipal Class Environmental Assessment for Water and Wastewater Projects 

A Municipal Class Environmental Assessment is a study that identifies the potential positive and negative effects of municipal infrastructure projects, and the process includes an investigation and evaluation of the impacts on the natural, social and technical environment. A Schedule B Municipal Class Environmental Assessment includes public and stakeholder consultation, evaluation of design alternatives, and identification of measures to mitigate any adverse impacts. The Schedule B Municipal Class Environmental Assessment Process is divided into the following three phases of the Class EA process:

Phase 1 – Identify the problem and/or opportunity
Phase 2 – Identify and evaluate alternative solutions
Phase 5* – Implementation

*Note Phases 3 and 4 are only conducted by a Schedule C or greater Municipal Class Environmental Assessment

In 2018, TRCA commenced Phase 1 of the Schedule B Municipal Class Environmental Assessment for Water and Wastewater Projects in accordance with the Environmental Assessment Act. A Notice of Intent initiating the project was published in the Markham Economist on April 26, 2018. Following initiation of the project, a Public Information Centre meeting was held on Tuesday, May 29th, 2018, in which interested community members attended and provided input on the planning and design process, including commenting on the proposed alternative solutions (Phase 2 – Identify and evaluate alternative solutions).

Upon identifying the preferred solution, TRCA will complete the environmental analysis and work with stakeholders to further inform the design process and complete the Project File. As part of the process, a Project File will be created to officially document project milestones and will serve as an opportunity for the public and stakeholders to provide further comment. A Notice of Completion will be published in fall 2018 to invite interested community members and regulatory agencies to review and comment on the Project File.

Scope of Work

Next steps include:

      • Project File and Notice of Completion following the 30 day review period
      • Development of detailed designs based on the preferred alternative solution
      • Obtain all necessary permits and approvals to proceed to construction
      • Construction tentatively scheduled for summer 2020, pending available budget and receipt of permits and approvals


Construction Information

Construction information showing work area, access areas, tentative schedule and construction highlights will be updated once the project commences in summer 2020.

Public Consultation 

To view project notice and consultation material, follow the links below:
Notice of Intent
Public Information Centre Meeting Presentation
German Mills Settlers Park Sanitary Infrastructure Protection Concepts & Evaluation Public Consultation Comment Form

Project Updates

Recent storm events in summer 2018 have caused accelerated erosion in select areas of German Mills Settlers Park. This has caused the partial exposure of a maintenance hole at the upstream limits of the proposed project (see Figure 2 above). As a result, TRCA is currently preparing to implement emergency interim sanitary protection works to stabilize the at-risk infrastructure until the planned permanent solution can be installed in 2020. The remedial works are tentatively scheduled to commence in late September 2018, pending the receipt of all necessary permits and approvals. Construction is anticipated to be completed in October 2018. Machinery access will utilize the park entrance from John Street. Please note the trail will be closed during work hours and will be reopened during evening and weekends. For your safety, please respect all posted construction signs and stay clear of the work areas and equipment. Your continued cooperation and patience is appreciated.

Please click the Notice of Construction project signage image below to view full sized version of the image.

Contact Us

For more information regarding this project, please use the contact details outlined below:
Phil Wolfraim, Project Manager 
Erosion Risk Management
Restoration & Infrastructure Division