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Operational Noise & Vibration

How Operational Noise & Vibration Assessments Work

The Operational Noise and Vibration Impact Assessment was conducted as follows:

  1. Noise and Vibration Monitoring: Monitors were placed to establish existing baseline conditions. Modeled existing noise levels during the daytime were within 1 dB of the measured results during the daytime period, and within 3 dB during the nighttime period. Monitored data confirmed that modeled baseline conditions are in line with existing noise levels.
  2. Noise and Vibration Predictions: Noise modelling and vibration analyses were conducted to predict the noise and vibration impacts at locations adjacent to the corridor, and to identify the mitigation solutions that will best manage noise and vibration impacts.
  3. Noise and Vibration Assessment Report: The noise and vibration analyses, impact predictions and mitigation recommendations are identified and documented in the assessment report. Solutions can include noise barriers to address predicted noise impacts, and rubber mats placed under the track structures (ballast mats for ballasted tracks such as GO tracks) and specialized fasteners to isolate rails from substructure and ground (resilient rail fasteners) to address predicted vibration impacts. Mitigation measures identified as part of the noise and vibration impact assessment will be implemented as part of construction to address and reduce the expected noise and vibration impacts. Further modelling analyses are typically conducted during detailed design to refine mitigation requirements

Transparent noise wall along Dundas Street West, north of Bloor Street West in Toronto.

Transparent noise wall along Dundas Street West, north of Bloor Street West in Toronto.

400 Carlaw Avenue

Noise monitor example.

6, 8 and 10 Paisley Avenue

Noise wall example.

Assessed Points of Reception

To assess the potential noise and vibration impacts of train operations in the joint corridor, noise-and vibration-sensitive points of reception, also referred to as receptors, were identified along the corridor to represent a given sensitive land use area. A sensitive land use area is an area with several noise and/or vibration sensitive receptors in close proximity to each other.

Within each sensitive land use area, a sample receptor was selected to represent a dwelling with the highest expected noise and/or vibration levels (often, a receptor that is closest to the tracks). A total of 28 representative noise receptors (see Lakeshore East Joint Corridor Noise and Vibration Operations Report for details) were selected for this study and include:

  • residences, including single-family dwellings and existing or proposed condominiums/apartments;
  • the proposed school south of Mill Street; and
  • the Jimmie Simpson Recreation Centre building.

map of noise receptors.

Operational Noise Assessment – Criteria & Methods

The operational noise assessment has been conducted using the methods and criteria defined in the following provincial guidance:

  1. Ministry of Energy and Environment (MOEE)/GO Transit Draft Protocol for Noise and Vibration Assessment (1995)
  2. MOEE/TTC Protocol for Noise and Vibration Assessment for the Proposed Yonge-Spadina Subway Loop (1993)

In accordance with provincial guidance, noise mitigation will be investigated if noise is predicted to exceed any of the following criteria:

MetricGO Limits*Ontario Line
Daytime Noise Impact [Leq,16hr] (16-hour average, 7 a.m. to 11 p.m.) 5 dB higher than pre-project sound levels or 55 dBA**5 dB higher than pre-project sound levels or 55 dBA
Nighttime Noise Impact [Leq,8hr] (8-hour average, 11 p.m. to 7 a.m.)5 dB higher than pre-project sound levels or 50 dBA5 dB higher than pre-project sound levels or 50 dBA
Subway Vehicle Lpassby***Not applicable to non-subway trains80 dBA

 

The Ministry of Environment, Conservation and Parks defines perceptibly of noise impacts as follows:

Increase in Sound Level Perception 
0 to 2.99 dB Insignificant 
3 to 4.99 dB Noticeable 
5 to 9.99 dB Significant 
10 dB or greater Very Significant 

 

*GO Limits noted apply to GO, VIA and freight trains operating in the rail corridor.
**dBA – Noise level adjusted to how humans experience different frequencies.
***Lpassby -Represents allowable noise level associated with a train passing by.

Operational Noise Assessment – Criteria & Methods

  • Models were prepared to predict existing railway noise conditions and the future scenario with both the Ontario Line and expanded GO rail services, including the existing three Lakeshore East GO tracks and future alignment changes to add two Ontario Line tracks and one GO track.
  • Daytime noise impacts were predicted using outdoor receptor locations (e.g., backyard or front yard) associated with a residence or a building façade if no outdoor areas or amenity areas were available (e.g., at condo or apartment buildings).
  • Nighttime noise impacts were predicted using receptors at building façades, intended to represent a bedroom window.
  • Receptor heights were estimated using the number of storeys of each building (e.g., 1.5 metres for one storey, 4.5 metres for two storeys, etc.). Height of receptors located in high-rise buildings were calculated based on the height of the storey with the highest expected noise levels.

Additional Noise Mitigation

In addition to protocol objectives, Metrolinx is seeking to limit Leq,16hr (daytime) and Leq,8hr (nighttime) noise impacts from the project to existing modeled levels at receptors between Eastern Avenue and Pape Avenue, where feasible, even for receptors with predicted noise impacts that do not require mitigation investigation per the MOEE/GO Protocol and/or MOEE/TTC Protocol.

Operational Noise Assessment – Criteria & Methods

According to both protocols, noise mitigation measures will be considered where post-project daytime (7 a.m. to 11 p.m.) and nighttime (11 p.m. to 7 a.m.) noise exposure levels are expected to increase by at least 5 dB from corresponding modeled pre-project levels or protocol objectives (55 dBA for daytime and 50 dBA for nighttime) – whichever is greater. As existing daytime and nighttime noise levels are predicted to be greater than the MOEE/GO and MOEE/TTC minimum limits of 55 dBA Leq,16h during the daytime and 50 dBA Leq,8h during the nighttime, the existing modeled daytime and nighttime levels were adopted as the objective noise levels for the assessment at all locations.

For the Ontario Line operations, noise mitigation measures will also be investigated where post-project vehicle pass-by noise exposure levels of Ontario Line vehicles passing by are expected to reach 80 dBA.

map of noise receptors.

Operational Noise – Impact Assessment Results & Next Steps

Without mitigation, noise impacts are predicted to exceed the MOEE/GO protocol criteria at nine of the 28 assessed locations. All nine locations are between Eastern Avenue and Pape Avenue (see Lakeshore East Joint Corridor Noise and Vibration Operations Report for details). At 19 locations, no exceedances were observed, and at eight locations, reductions of as much as 6.1 dB were observed.

Noise barriers that are 2.5 to 6.5 metres tall on both sides of the corridor were investigated to meet the noise protocols criteria and reduce predicted noise impacts at noise sensitive receptors located along the corridor between Eastern Avenue and Pape Avenue to existing predicted levels where feasible.

Implemented noise barriers are predicted to:

  • effectively meet MOEE/GO and MOEE/TTC criteria at all sensitive receptors along the joint corridor; and
  • achieve reductions below the predicted existing noise levels at most assessed receptors along the joint corridor, up to 10 dB at some locations.

Though upper floors of five high-rise buildings are predicted to have some residual impacts (1.7-4.2 dBA), these are in the insignificant to noticeable range and consistent with criteria.

As part of the Lakeshore East Joint Corridor early works, Metrolinx will install noise barriers with a minimum height of five metres, in alignment with the noise barrier implementation approach planned to be undertaken by GO Expansion. This will provide additional noise mitigation.

Built Heritage Resources & Cultural Heritage Landscapes

map of noise barriers.

Retaining & Noise Wall Design Elements

Metrolinx will be seeking feedback from the Riverside and Leslieville communities on the look and feel of the retaining and noise walls, as well as the landscaping strategies directly adjacent to the rail corridor.  This consultation is planned to be launched in late September 2021.

1. Retaining & Noise Wall Options 

The options are considering:

A) Retaining Wall 

image of retaining wall

B) Retaining Wall

Retaining wall 1

Retaining wall 2

Retaining wall 3

2. Wall Mitigation & Vegetation 

The options are considering:

C) Embankment 

embankment

Garden

D) Vertical Wall 

vertical wall 1

vertical wall 2

3. Tree Protection & Replanting 

The options are considering:

E) Tree Planting

tree planting option 1

tree planting option 2

tree planting option 3

tree planting option 4

Operational Vibration Assessment – Criteria & Methods

Vibration monitoring was conducted to establish baseline vibration levels at specific vibration sensitive locations that do not have prescribed limits under Ontario guidelines (e.g., theatres, hospitals, recording studios), as they accommodate spaces and equipment that are typically more sensitive than residential locations, in order to determine appropriate vibration limits for these locations. For residential locations, vibration limits were determined using calculated existing levels at receptors or the defined limits per the MOEE/GO and MOEE/TTC protocols. The operational vibration assessment from the Ontario Line and GO vehicles has been conducted in accordance with the provincial guidance (MOEE/TTC and MOEE/GO protocols). Vibration mitigation will be investigated if the project is predicted to exceed any of the following criteria:

MetricGO Train LimitsOntario Line Vehicle Limits
RMS* vibration velocityIncrease of 25% above the higher of existing vibration levels, or 0.14 mm/s (equivalent to 75 VdB**)0.1 mm/s (equivalent to 72 VdB)

 

*Root mean square (RMS) velocity is  a measure of vibration amplitude and an indication of vibration energy.
** VdB is  the vibration level adjusted to how humans perceive vibration.

rendering.

Operational Vibration – Impact Assessment Results & Next Steps

Vibration receptors are generally located in the same locations as the noise assessment receptors but at ground level. Vibration levels have been predicted in accordance with the General Vibration Assessment procedures described in the US FTA Vibration Protocol. Vibration calculations and predictions were made using the “worst-case” scenario with trains operating on both sets of tracks.

Without mitigation, vibration from the Ontario Line and GO track operations is predicted to exceed MOEE/GO and MOEE/TTC Protocol limits at nine of the 20 assessed receptor locations. The required reductions of 2 – 7 dB are anticipated to be achieved using proven conventional solutions such as resilient rail fasteners or resilient supported ties (for both Ontario Line and GO tracks), and ballast mats (for GO tracks only, with ballasted trackbed).

A detailed vibration analysis, including testing local ground conditions, will be conducted during detailed design in order to refine mitigation requirements.

Vibration mitigation for GO tracks will be implemented as part of the Lakeshore East Joint Corridor early works. Vibration mitigation for Ontario Line tracks will be implemented as part of the main Ontario Line contracts.

rendering.