GO Expansion - New Track & Facilities Project Proposed Don Valley Layover – What will the Layover Facility be used for? Storage • Off-peak storage of 3 GO trains in a linear configuration. Maintenance • The following types of maintenance activities will be carried out at the Don Valley Layover: o Daily Inspections - general visual inspections to identify any obvious defect or damage to equipment prior to trainsets entering revenue service. These types of inspections usually take less than an hour to complete per trainset. o Cleaning, servicing and temperature control of rolling stock. o Sanitary flushing and replenishment of washroom supplies. This includes emptying sanitary tanks from rolling stock into temporary storage facilities. Temporary storage facilities will be pumped out at regular intervals.

GO Expansion - New Track & Facilities Project Proposed Don Valley Layover - Why is a Layover Needed at this Location? • In order to achieve the targeted GO Expansion service levels, layovers are required across the network for train storage and maintenance.

• A layover at this location would reduce congestion at which is a bottle-neck in the GO network.

• A layover at this location would reduce frequency and length of non-revenue train movements and provide storage and light maintenance for 3 trains during off-peak periods. Don Branch looking south from Bloor • Some GO Expansion upgrade works and other infrastructure construction (DVP is to the left) through the Lower Don portion of the City will reduce storage capacity in the Don/Wilson yard further necessitating the need for train storage in this area.

• Sites to the south of the Union Station corridor have been considered, but to cross the entire corridor with these 3 terminating trains is beyond the capability of the infrastructure creating congestion on the approach to Union Station.

• A layover at this location would make use of the existing track on the - owned Don Branch. Don Branch looking north from Bloor Viaduct (DVP is to the right) GO Expansion - New Track & Facilities Project Proposed Don Valley Layover Facility - City of The Don Valley Layover Facility design has been updated since Round 2 of public consultation to reflect stakeholder feedback. Changes have been made to relocate buildings to a higher elevation to further floodproof the facility and shift building facilities away from the Lower Don Trail.

Proposed Site Plan GO Expansion - New Track & Facilities Project Proposed Don Valley Layover Facility - City of Toronto

Revised Design Elements: • Crew services and buildings have been moved to a higher elevation, adjacent to the storage track, within Metrolinx’s right-of-way. • The storage track remains within Metrolinx’s right-of-way. Design Elements: • Storage and light maintenance of 3 GO Trains in a linear configuration. • Trains will be serviced by wayside power. This is a non-electrified layover facility. • The facility includes crew services building, sanitary storage and staff parking. • Retaining walls will be required to limit fill. • Similar to previous design iterations, the layover will utilize the inactive Metrolinx-owned Don Branch for track storage and access to the mainline track leading to Union Station to the south. • Vehicle access will be provided from the / ramp using an existing park access road. • Construction fencing/gates will provide a separation between Lower Don Parklands users and construction activities. • Permanent fencing will delineate the facility from the Lower Don Trail. • The facility will be secured through an access gate and security fencing.

GO Expansion - New Track & Facilities Project Proposed Don Valley Layover Facility - City of Toronto

Proposed Site: Aerial View Proposed Site: View from Don Valley Parkway looking North Note: conceptual design subject to further study Note: conceptual design subject to further study

GO Expansion - New Track & Facilities Project Proposed Don Valley Layover Facility - City of Toronto

Proposed Site: View from the Lower Don Trail Note: conceptual design subject to further study

GO Expansion - New Track & Facilities Project Proposed Don Valley Layover Facility - City of Toronto Natural Heritage Update • The revised design has shifted buildings and other layover facilities outside of Environmentally Significant Areas (ESAs), as designated by the City of Toronto. The ESA boundaries are represented by the orange area in the map on the left.

• The overall footprint of the layover facility has been significantly reduced to limit vegetation removals and make use of previously disturbed area to the greatest extent possible.

• The site will utilize existing tracks (Don Branch) which are currently not in use, therefore, no additional tracks will be required.

• Access to the site during construction, operation and maintenance will be via an existing park access road that is currently utilized by Hydro One and the City of Toronto to access a hydro substation and the , respectively. Metrolinx will improve and extend the existing park access road in consultation with the City of Toronto.

• The layover has been designed to minimize intrusion into Helliwell's Hill wetland by utilizing an existing park access road for the Prince Edward Viaduct. The wetland area is shown in green in the map on the left. • Utilizing the existing park access road also reduces the amount of fill that is required within the regulatory floodplain (shown in yellow in the map on the left) Natural Heritage Features Map GO Expansion - New Track & Facilities Project Proposed Don Valley Layover Facility - City of Toronto Floodplain Update • The map shown to the left represents the flood risk within the Valley, which is regulated by Toronto and Region Conservation Authority (TRCA).

• Changes have been made to the Don Valley Layover to relocate the buildings to a higher elevation and further floodproof the facility, as well as, to provide a separation from the Lower Don Trail.

• Buildings are now located outside of the 100-year floodplain and at higher elevation to accommodate TRCA's regulatory storm level. The revised location means that buildings and other facilities are less likely to be impacted in the event of a major storm.

• The facility will be designed to ensure hydraulic conveyance is conserved to minimize on-site or off-site impacts.

• Additional studies to reduce future flooding risks will be undertaken during detailed design.

• Metrolinx is committed to continued consultation with the City of Toronto and TRCA as it relates to the Don Valley TRCA Floodplain Map Layover design. GO Expansion - New Track & Facilities Project Effects and Proposed Mitigation Measures Proposed Don Valley Layover Facility - City of Toronto

Type of Effect Description of Potential Effects Proposed Mitigation Measure

• A Drainage and Stormwater Report, an Erosion and Sediment Control Plan and detailed • The proposed access road is located in close proximity drainage design will be prepared to further inform stormwater management and to the Don River, which may result in potential identify erosion and sediment controls that will be implemented during construction. challenges with erosion and sediment control. • Requirements for stormwater quantity and quality controls will be carefully reviewed and Stormwater • The proposed layover requires approximately 370 implemented as required. metres of retaining wall, which will result in disruption Management to existing drainage patterns and additional challenges • A hydraulic assessment will be completed for the Don River prior to construction to with temporary drainage management during determine potential flooding effects and identify further mitigation measures, if construction. required. • Further mitigation measures for flooding will be determined in consultation with the TRCA.

• As part of detailed design, efforts will be made to minimize visual impacts as much as possible. • The need for retaining walls to limit fill will result in increased visual disturbance. • A Design Excellence process will be followed to integrate the new infrastructure into the existing environment to reduce the extent of visual impacts. This will include Impacts on the composition and character of current Visual • landscaping and screened enclosures, with particular attention given to waste disposal views along the Lower Don Trail and surrounding park and material storage areas. space. • Light sources will be used that minimize layover visibility to Lower Don Parklands users and environmentally sensitive areas. • Anti-graffiti coating will be applied on public-facing retaining walls. GO Expansion - New Track & Facilities Project Effects and Proposed Mitigation Measures Proposed Don Valley Layover Facility - City of Toronto

Type of Effect Description of Potential Effects Proposed Mitigation Measure

• Tree/Vegetation removal or injury, compensation and permitting/approvals (as required) will be undertaken in accordance with Metrolinx’s Vegetation Management Guidelines and Tree Removal Strategy. • Performing vegetation removal outside the typical breeding period for birds, which is between March and September. This will consider potential occupation of treed roosts (individual trees) by bats and Milkweed by Monarch caterpillars. Greater vegetation removals are required for the • • An Integrated Vegetation Management Plan will be developed and implemented in revised layover configuration since facilities have been accordance with Metrolinx’s Vegetation Management Guidelines and Tree Removal shifted away from the already-disturbed areas beneath Strategy. the Prince Edward Viaduct. • The revised design has shifted buildings and other layover facilities outside of Natural • Siting of the layover buildings has the potential to Environmentally Significant Areas (ESAs), as designated by the City of Toronto. Environment increase flooding potential downstream. • The layover has been designed to minimize intrusion into Helliwell's Hill wetland by • Proposed infrastructure is now closer to wetland areas, utilizing an existing park access road for the Prince Edward Viaduct. increasing the potential for impacts during construction. • Utilizing the existing park access also reduces the amount of fill that is required within the regulatory floodplain.

• Facility has been redesigned to ensure buildings can be floodproofed to the TRCA regulatory design storm. The revised location means that buildings and other facilities are less likely to be impacted in the event of a major storm. • Additional studies to reduce future flooding risks will be undertaken during detailed design. • Metrolinx is committed to continued consultation with the City of Toronto and TRCA. GO Expansion - New Track & Facilities Project Effects and Proposed Mitigation Measures Proposed Don Valley Layover Facility - City of Toronto

Type of Effect Description of Potential Effects Proposed Mitigation Measure

• Construction fencing/gates will provide separation between Lower Don Parklands users and construction activities. • Construction of the layover has the potential to impact • Permanent fencing will delineate the facility from the Lower Don Trail. Where the Lower Don Trail. proposed access road is close to the Lower Don Trail, Metrolinx is proposing removable • Layover construction has the potential to affect the City bollards in the permanent condition for separation between Lower Don Parkland users of Toronto’s Master Plan for the Lower Don Trail, as well and service vehicles. as recreational activities and public art installations. • Metrolinx will engage with the City of Toronto to incorporate municipal requirements as Construction and operation of the layover will require a best practice, where practical, and may obtain associated permits and approvals. Land Use • an agreement between Metrolinx and the City of • Metrolinx will obtain a permanent easement from the City of Toronto for the use of the Toronto for the access road. park access road connecting the layover facility with the entrance from the Don Valley • Nuisance effects may be experienced by the public Parkway/Bayview Avenue interchange. during construction, which are short-term construction • A Communication and Complaints Protocol will be developed prior to and effects that are difficult to prevent (noise, dust, etc.). implemented during construction. • A Construction Monitoring Plan will be developed that identifies site-specific mitigation measures to be enacted before work begins. Mitigation measures contained within the plan will be regularly monitored during construction. GO Expansion - New Track & Facilities Project Effects and Proposed Mitigation Measures Proposed Don Valley Layover Facility - City of Toronto

Type of Effect Description of Potential Effects Proposed Mitigation Measure

• Construction of the proposed layover, including its various components (buildings, layover yard tracks, • Baseline vibration monitoring will be completed to ensure the parking area, fencing, etc.) has the potential to result in • Prince Edward Viaduct is not affected by construction. indirect negative effects to the Prince Edward Viaduct, Cultural Heritage which is a known cultural heritage resource. These • Staging areas will be selected so that they are non-invasive and avoid heritage indirect disturbances may result from soil disturbance, attributes. potential vibration effects, and construction of ancillary • A Heritage Impact Assessment will be completed to qualify and mitigate the indirect buildings to the north of the . heritage impacts that are expected for the Prince Edward Viaduct.

• Proposed facilities are in proximity to utilities (oil pipelines, gas main, hydro lines and • All utility assets within the Metrolinx layover site will need to be removed and relocated telecommunication cables, amongst others). and/or locally lowered with a casing pipe across all tracks. Potential utility impacts have been classified into three Where new utility crossings are proposed, application for a new utility crossing Utilities • • different categories: minor, medium or major. Conflicts agreement will be required. Where modifications to an existing utility crossing takes will be resolved with affected utility companies and place, updates to an existing utility crossing will be needed. relocations will occur, where appropriate.

GO Expansion - New Track & Facilities Project Effects and Proposed Mitigation Measures Proposed Don Valley Layover Facility - City of Toronto

Type of Effect Description of Potential Effects Proposed Mitigation Measure

• An Erosion and Sediment Control Plan will be prepared to identify erosion and sediment controls that will be implemented during construction to minimize the risk of • Excavation and backfill may be required to sedimentation. Earth accommodate building footprints. Management • A Spill Prevention and Response Plan will be developed prior to and implemented

during construction to ensure procedures and policies are in place to minimize effects to wetlands and watercourses.

• All projects begin with a comprehensive Stage 1 • In the event that previously unknown archaeological materials or human remains are Archaeological Assessment of affected lands to encountered during construction, all work will cease. The location will be protected by determine and evaluate areas of archaeological employing a buffer and further Archaeological Assessment will occur. The local potential. police/coroner as well as the Bereavement Authority of will be contacted, as Archaeological appropriate. • Based on results of the Stage 1 assessment, further • If final limits of the Project footprint are altered and fall outside of the assessed study Stage 2 Archaeological Assessment was completed area, additional Archaeological Assessments will be conducted. that cleared the site of future archaeological potential. • All Archaeological Assessment findings will be shared with Indigenous communities.

GO Expansion - New Track & Facilities Project Effects and Proposed Mitigation Measures Proposed Don Valley Layover Facility - City of Toronto

Type of Effect Description of Potential Effects Proposed Mitigation Measure

• Temporary short-term road closures may be required during construction. • A Construction Management Plan and Traffic Management Plan will be developed prior to construction to further identify impacts and associated mitigation. These plans will be The proposed layover is not expected to result in Traffic • circulated to local municipalities/road authorities for review and discussion before being significant effects to the surrounding transportation implemented during construction. system because the number of expected daily trips to/from the facility is very low.

• A Phase I Environmental Site Assessment (ESA) was completed for the proposed Don Valley Layover Site. • A Soil and Excavated Materials Management Plan will be developed prior to Based on information gathered to-date and construction for the handling, management and disposal of all excavated material. observations made, the Phase I ESA indicates the likelihood of encountering contamination is low. • Baseline condition sampling will be completed for soil and groundwater (a pre- Contamination construction assessment). By completing these studies, baseline conditions can be • Geotechnically unsuitable soils will likely be removed compared to the post-construction soil and groundwater conditions to determine if during construction in order to achieve a proper additional mitigation or remediation is required. substrate. Similarly, backfill materials will likely need to be imported to form the foundation.

GO Expansion - New Track & Facilities Project Future Design Commitments Proposed Don Valley Layover Facility The following key commitments will be adhered to as Metrolinx continues to advance the design of the Don Valley Layover following the TPAP: • To support safety and wayfinding, signage and fencing shall be provided for Lower Don Parklands users during construction of the facility. • The Lower Don Trail will remain open and accessible to the public during construction, and reconstructed (if required) to pre-construction conditions. Retaining wall with planting to provide visual screening – Years 1-5 • The layover facility shall be designed to be floodproofed to the Regulatory Storm event. • Maintenance activities, such as snow clearing, will not impact the Lower Don Trail. • Erosion and sediment control measures will be implemented and maintained during construction to avoid impacts to the Lower Don Trail and Don River. Particular attention will be given to the architecture and landscape design of the facility in order to reduce visual impacts where feasible. The facility will include: • Landscaped and planted areas that are environmentally sustainable and will be selected with consideration of the surrounding area and the City of Toronto's Green Standards.

• Screened enclosures to minimize visual impacts (particular attention will focused on the waste disposal Retaining wall with planting to provide visual screening – and material storage areas). Years 5-10 • Light sources that minimize impacts on Lower Don Parklands users and environmentally sensitive areas. The benefits of landscape screening will accrue over time • Anti-graffiti coating on public-facing retaining walls. Lighting will be shielded to minimize Metrolinx shall continue to communicate and engage with stakeholders during detailed design and visibility from adjacent sensitive areas construction planning to address municipal concerns.