SS WILSON ASSOCIATES Consulting Engineers

SS WILSON ASSOCIATES

Consulting Engineers

REPORT NO. WA08-079

NOISE AND VIBRATION IMPACT STUDY

VIVA NEXT

YONGE SUBWAY EXTENSION

FINCH AVENUE TO HIGHWAY 7

SUBMITTED TO:

YORK REGION RAPID TRANSIT CORPORATION

C/O M C CORMICK RANKIN CORPORATION

2655 SHERIDAN WAY

MISSISSAUGA, ONTARIO

L5K 2P8

PREPARED BY:

HEADER MERZA, P.ENG.

SENIOR PROJECT ENGINEER

APPROVED BY:

HAZEM GIDAMY, P. ENG.

PRINCIPAL

JANUARY 28, 2009

SSWA INC. 15 Wertheim Court, Suite 211, Richmond Hill, Ontario, L4B 3H7

Tel: (905) 707-5800 Fax: (905) 707-5801 e-mail: info@sswilsonassociates.com

www.sswilsonassociates.com

& www.noisetraining.com

NOISE AND VIBRATION IMPACT STUDY

VIVA NEXT

YONGE SUBWAY EXTENSION

FINCH AVENUE TO HIGHWAY 7

SUBJECT PAGE

1.0 INTRODUCTION 1

2.0 NOISE AND VIBRATION CRITERIA

3.0 ANALYSES AND RESULTS

4.0 CONSTRUCTION NOISE AND VIBRATION IMPACTS

5.0 SUMMARY AND RECOMMENDATIONS

FIGURES

ATTACHMENT 1: GLOSSARY

5

9

23

26

ATTACHMENT 2: NOISE AND VIBRATION CRITERIA

ATTACHMENT 3: ROAD TRAFFIC DATA

ATTACHMENT 4: CALCULATIONS

ATTACHMENT 5: SPECIFIC NOISE ASSESSMENTS

Jan 28, 09 Final Report.doc

1.0 INTRODUCTION

1.1 BACKGROUND

The services of SS Wilson Associates were retained by McCormick Rankin Corporation on behalf of York Region Rapid Transit Corporation to carry out a Noise and Vibration Impact

Assessment Study for the proposed Yonge Subway Extension from Finch Avenue to

Highway 7.

The objectives of the study are to:

•

Participate in the preparation of the Environmental Project Report.

•

Identify the potential noise and vibration sensitive land uses.

•

Determine the existing ambient noise and vibration levels.

•

Predict the proposed subway line and bus stations noise and vibration levels.

•

Assess the potential noise and vibration impacts at all potential points of reception.

•

Study the feasibility of applying noise and vibration mitigation measures, and recommend same, where warranted.

Figure 1 illustrates the general location of proposed Yonge subway extension.

This study is based on collective efforts of this firm as well as of McCormick Rankin

Corporation, YC 2002 and VIVA. Overall direction on issues related to engineering and the environment were provided by McCormick Rankin Corporation.

This study should, therefore be read in conjunction with the Environmental Project Report and other background reports prepared by other study team members.

1.2 OVERVIEW OF THE APPROACH

Noise is generally defined as any unwanted sound. In this case, the noise under consideration is the noise associated with the proposed Yonge Subway Extension. The

Glossary section in Attachment 1 provides definitions of technical terms to assist in understanding the principles and terminology used in this report. The report considers two main sources of noise, the ground-borne noise due to the movement of the trains along the underground tracks and environmental noise due to bus/car movements/idlings.

Noise impact is a comparative evaluation of the new or intruding noise versus the existing or ambient noise in the area. Noise impact is also a comparative evaluation of the new or intruding noise versus a present sound level limit criterion. The degree of noise impact varies depending on the difference between the new and existing sound levels, i.e. the higher the new sound level is above the existing sound level, the higher the impact.

1

A combination of quantitative and qualitative approaches to noise and vibration impact assessment have been used in this study to enable York Region Rapid Transit

Corporation, the study team and the public to understand the potential effects. In this study, the hourly Leq (equivalent sound level) and the Lmax (maximum sound level) descriptors are used in the analysis and assessment of noise impacts while the Lv

(maximum vibration level) descriptor is used in the analysis and assessment of vibration impacts.

The noise and vibration impact assessment is primarily focused on the changes in noise and vibration as well as comparison with absolute criteria levels in accordance with the following general principles:

1. Assess the existing or future-do-nothing environment.

2. Predict the future project noise and vibration levels.

3. Assess the impact relative to the applicable criteria (see Section 2).

4. Recommend noise and vibration control measures, where warranted and where technically and economically feasible.

Due to the nature of the potential sources of noise and vibration, the applicable noise/vibration criteria for the undertaking necessitated evaluation of each source independently as follows:

1. Subway line ground-borne vibration

2. Subway line noise generated inside buildings as a result of ground-borne vibration

3. Steeles and Richmond Hill bus stations noise

4. Longbridge/Langstaff Hydro corridor car park noise

5. Subway line viaduct crossing over the East Don River noise

6. Subway electrical substation noise

7. Subway stations air ventilation shafts noise

1.3 BRIEF DESCRIPTION OF STUDY AREA AND PROPOSED UNDERTAKING

Study Area

The study area includes the Yonge Street corridor from Finch Avenue to north of Highway

7 (High Tech Road) with reasonable distances to the east and west of Yonge Street.

Figure 1 illustrates the study area limits.

The Project

The project will entail the following elements:

2

Subway Line

The Yonge Subway presently terminates at Finch Station. The project calls for the extension of the subway from its current terminus at Finch Station northward to north of

Highway 7 near High Tech Road.

Subway Stations

Six underground subway stations are proposed as follows:

- Royal Orchard Station

- Richmond Hill Station

Bus Terminal Stations

Two bus terminal stations are proposed as follows:

- Richmond Hill Station

Car Park

A commuter car park lot is proposed within the hydro corridor lands located north of

Longbridge Road, south of Highway 407 on the east side of Yonge Street.

Subway Viaduct Crossing

A viaduct is proposed under Yonge Street crossing over the East Don River, the vertical profile of Yonge Street will be raised to provide sufficient clearance over the East Don

River.

Subway Transformer Substation

Subway transformer substations are proposed at Steeles Station, Clarke Station, Royal

Orchard Station and within the Richmond Hill Centre lands at the north-west corner of

Highway 7 and the railway tracks.

Subway Ventilation Shafts

Subway ventilation shafts with openings at ground surface level are proposed at various intervals on both sides of the subway line alignment and in the vicinity of the subway stations.

Figure 2 illustrates an overall view of the proposed subway extension alignment and proposed subway stations. Figures 3.1 and 3.2 illustrate the locations of the proposed

3

Steeles and Richmond Hill stations. The recommended subway profile is shown in Figures

4.1 to 4.9.

4

2.0 NOISE AND VIBRATION CRITERIA

The proposed Yonge Subway Extension is comprised of two distinct sources of noise and/or vibration:

1. Ground-borne vibration - the subway trains will be moving in tunnels which radiate ground-borne vibration and noise that propagate through the soil to the near-by buildings. The resulting building vibration can cause intrusions in the form of mechanical motion or audible sound within the buildings.

2. Air-borne noise - the proposed bus terminal stations, commuter car park, subway viaduct crossing, transformer substations and air shafts will produce noise that propagate through the air to the nearby buildings.

For the purposes of meeting the Ministry of the Environment (MOE), York Region, City of

Toronto, Toronto Transit Commission (TTC), City of Vaughan, Town of Markham and

Town of Richmond Hill guidelines for the assessment of noise and vibration due to the proposed subway undertaking, three different criteria have been considered.

Train movements on the subway line and on the viaduct crossing are considered as a rail transit system which will be assessed on the basis of the MOE/TTC Protocol as well as other generally acceptable criteria.

The bus terminal stations, commuter car park, subway transformer substation and air shafts are considered by the MOE as "Stationary Sources" and the relevant MOE sound level criteria included in Publication NPC-205 will apply.

2.1 MOE/TTC SUBWAY NOISE AND VIBRATION CRITERIA

The applicable criteria for noise and vibration are included in the MOE/TTC Protocol For

Noise and Vibration Assessment For the Proposed Yonge-Spadina Subway Loop”, June

16, 1993. Attachment 2 includes a copy of the MOE/TTC Protocol.

Wayside noise and vibration criteria provide a basis for assessing impact and determining the type and extent of mitigation measures necessary to minimize any general community annoyance or minimize interference with any particularly sensitive nearby land use or activity.

Noise sensitive land uses generally include existing residential developments, proposed residential developments which have received municipal approval, nursing homes, group homes, hospitals and institutional land uses where noise impact may be detrimental to the functions conducted within such buildings.

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For the purposes of this assessment and in accordance with the MOE/TTC Protocol noise and vibration impacts on commercial and industrial areas generally need not be considered, except where there are buildings that have vibration sensitive equipment.

In general, for at-grade rail transit operations, both wayside airborne noise and groundborne vibration impacts need to be examined, although the ground-borne noise is generally masked by the wayside airborne noise. In areas where the rail transit line is in subway, both ground-borne noise and vibration may be perceptible.

The recommended criterion for the maximum ground-borne vibration velocity (rms) level due to rail transit train operations applicable to noise/vibration sensitive land uses is 0.10 mm/sec. The criterion applies to the vertical vibration of the ground surface or floor surface, and it should be applied outdoors and referenced to the building or area under consideration. Ground-borne vibration which complies with the recommended design criterion will hardly be imperceptible in all cases. However, the level will be sufficiently low so that no significant intrusion or annoyance should occur.

The vibration levels predicted/reported in this Report are presented in Lv dB re 10

-6 inch/second (A vibration velocity level, Lv, of 0.1 mm/second is equivalent to approximately

71.9 dB reference 10

-6

inch/second).

With regards to the application of the vibration criterion, the MOE/TTC Protocol specifically excludes vibration due to maintenance activities on the subway line.

It is also important to note that while the MOE/TTC Protocol recognizes that ground-borne vibration can produce air-borne noise inside a structure, it does not provide any direction on such noise criteria and instead, relies on the above-noted vibration criterion.

Due to the presence of noise-sensitive areas in close proximity to the proposed subway, we are recommending that the objective criterion for ground-borne noise due to transit train operations applicable to noise-sensitive land uses be 35 dBA. Ground-borne sound levels which meet this criterion are likely to be audible in all cases, but should be low enough that no significant intrusion or annoyance would occur.

It is important to note that ground-borne noise impact on general non-sensitive commercial and industrial areas need not be considered as per the MOE direction.

Other Recommended Subway Line Noise and Vibration Criteria

As stated above, the MOE/TTC June 16, 1993 Protocol does not address ancillary facilities

(such as bus stations, commuter car park lots, viaduct crossings, transformer substations and ventilations shafts/fans) and subway construction, which may be of concern with respect to this project.

Accordingly, the past practices of the TTC and other jurisdictions in North America were researched, based on which we are recommending the use of supplementary noise and

6

vibration criteria to reduce the potential impacts on buildings that are sensitive to subway vibration and noise.

The following Table 1 lists the recommended supplementary criteria used in this study:

TABLE 1

RECOMMENDED SUPPLEMENTARY SUBWAY LINE

NOISE AND VIBRATION CRITERIA

Land Use

Houses and Townhouses

Apartment Building

Institutional

Recommended

Vibration Velocity Level

Criteria, Lv*

1

70 dB

70 dB

70 dB

Recommended Indoor

Sound Criteria

35 dBA

35 dBA

35 dBA

Commercial

Industrial

75 dB

80 dB

40 dBA

45 dBA

Sensitive Buildings

Note: Lv is in reference to 10

-6

in/sec

65 dB

2.2 STATIONARY SOURCES OF NOISE CRITERIA

30 dBA

All sources that are to be treated as “Stationary Sources” will be subject to the MOE's criteria included in Publication NPC-205 (i.e. the higher of either the prevalent ambient sound levels or the exclusion limits for hourly Leq sound levels included in NPC-205). The criteria are based on the guidelines prepared by the MOE for the assessment of planned

"Stationary Sources" of sound.

Attachment 2 includes a copy of MOE Publication NPC-205.

The predicted and/or measured 1 hour equivalent sound level (Leq) of existing road traffic is normally compared with the predicted and/or measured 1 hour equivalent sound level

(Leq) from the source. Other applicable criteria are also referred to in MOE Publication.

NPC-205

In situations where the ambient is not significant, then the Ministry exclusion limits in

Publication NPC-205 would apply.

2.3 GENERAL IMPACT ASSESSMENT GUIDELINES FOR NOISE

The sound level criteria are also related to the existing ambient noise. Should the projected undertaking sound levels exceed the ambient levels, the impact on a noisesensitive receptor may be determined by comparing the projected undertaking levels with the established ambient levels.

7

The following Table 2 outlines the generally accepted impact assessment ratings of the excess above the established existing ambient levels:

TABLE 2

NOISE IMPACT ASSESSMENT

IMPACT ASSESSMENT TABLE

EXCESS/CHANGE IMPACT RATING

0 TO <3

=>3 TO <5 dBA

=5 To <10 dBA

Low

Noticeable

High

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3.0 ANALYSIS AND RESULTS

3.1 AMBIENT NOISE AND VIBRATION – SUBWAY LINE IMPACT ASSESSMENT

For the proposed Yonge Subway Extension, the potential for higher levels of groundborne vibration levels and the resulting low frequency “rumble” are two of the most important factors to consider for noise/vibration sensitive land uses located in close proximity to the subway alignment.

The general range of noise/vibration sensitive land uses includes residential dwellings/buildings, institutional facilities, heritage buildings, hospitals, group homes, places of worship and commercial establishments.

The MOE and the joint MOE/TTC Protocol as well as the general EA practices for noise/vibration rely on a series of absolute and relative noise/vibration criteria. The relative criteria recognize the importance of the “existing” background/ambient noise/vibration conditions for impact assessment purposes.

The dominant sources of ambient noise in the study area are essentially Yonge Street, major arterial roads and major collector roads with existing bus traffic on these roads.

The dominant sources of vibration in the area are bus/truck movements on roads, rail traffic on the CN/GO Transit rail lines and internally generated vibration levels in the surveyed buildings.

Attachment 3 includes the road traffic data used to establish the ambient noise, while

Attachment 4 includes sample ambient noise calculations.

The actually measured ambient noise and vibration levels are presented in the section to follow related to the selected points of reception.

3.2 POINTS OF RECEPTION

For the purpose of this study, fifty three (53) receptors denoted R1 to R53 were selected to represent all the noise and vibration sensitive areas used for assessment of the

•

•

•

• noise/vibration impacts as directed by the MOE criteria.

The study area contains the following land uses, which would be of immediate interest for noise/vibration assessment depending on their relative locations to the various sources:

Residential (21 receptors)

Institutional (6 receptors)

Heritage (4 receptors)

Commercial (22 receptors)

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a. Receptors along the subway line

Receptors within a distance setback of approximately 100 metres from the centreline of the closest subway track have been considered based on our detailed review of the project plans and numerous site visits and field investigations to the study area.

As the study team approached all the properties located within the area of influence from the subway line alignment, some of the owners/occupiers indicated that their properties may be affected by the subway and requested site-specific inspections, measurements of their ambient noise/vibration and assessment of the potential subway line impact.

Based on the feedback received by the study team from the property owners/occupiers in the study area, a decision was made to visit specific properties, to interview the owners/operators of such properties and to take ambient noise and vibration level readings.

Table 3 below includes all the properties selected for noise and vibration investigations:

TABLE 3

PROPERTIES SELECTED FOR NOISE & VIBRATION INVESTIGATIONS

RECEPTOR NAME AND

ADDRESS

Condominium

NATURE OF

BUSINESS

REASON FOR

SENSITIVITY TO

NOISE/VIBRATION

Perception/Annoyance/

Structural Damage

NOTES

Not Investigated

R2 Office Building

Apartment Building

(concrete)

Commercial Meeting Rooms/Halls Investigated

St.

St.

Bldg

St.-Medical

Clinic

Bldg

St.-Dental

Clinic

Medical

Apartment Building

(concrete)

Laboratory/Equipment/

Sensitive Machinery


Structural Damage

Medical


Sensitive Machinery

Investigated

Not Investigated

Investigated

Apartment Building

(concrete)


Structural Damage

Medical


Sensitive Machinery

Not Investigated

Investigated

10


ADDRESS

NATURE OF

BUSINESS

REASON FOR

SENSITIVITY TO

NOISE/VIBRATION

Arrangement Rooms

NOTES

St-Jerrett

Funeral

Homes

St-Act II

Residential

Home

Residential Houses and Townhouses


Structural Damage

Not Investigated

Investigated

St.-United

Optical

Sensitive Machinery

St.-Denture

Clinic

Medical


Sensitive Machinery

R14 Apartment Residential

Bldg.-7411

Yonge Street

Apartment Building

(concrete)

Townhomes and Townhouses


Structural Damage


Structural Damage .

Investigated

Not Investigated

Not Investigated

St.-Denture

Clinic

Medical

R17 Ballet

Academy

Commercial

R18 Residential Residential

Bldg Apartment Building

(concrete)



(concrete)



(concrete)



(concrete)


Sensitive Machinery

Annoyance to Noise


Structural Damage


Structural Damage


Structural Damage


Structural Damage

St.-Office Bldg

Investigated

Investigated

Not Investigated

Not Investigated

Not Investigated

Not Investigated

St.-Catholic

Cemeteries

Arrangement Rooms

11


ADDRESS

NATURE OF

BUSINESS


Condominium Apartment Building

(concrete)

R25

REASON FOR

SENSITIVITY TO

NOISE/VIBRATION


Structural Damage

Structural Damage

NOTES

Not Investigated

Not Investigated

St- Vishnu

Temple

Road-Dental

Clinic

Medical

Rooms, Teaching

Facility


Sensitive Machinery

Investigated

Home and Townhouses


Structural Damage

Not Investigated

Home and Townhouses


Structural Damage Not Investigated

R30 Langstaff

Elementary

School

St.-Private

High School

St.-Medical

Clinic

St.-Jerrett

Funeral

Homes

Street

Library

Investigated

Medical


Sensitive Machinery Investigated

Arrangement Rooms Investigated and Townhouses


Structural Damage

Not Investigated

R36

St.-Thornhill

Baptist Church

Old Yonge St.-

Heritage

Home

Office, Teaching

Facility

Investigated

Perception/Annoyance Investigated

12


ADDRESS

Street

NATURE OF

BUSINESS

REASON FOR

SENSITIVITY TO

NOISE/VIBRATION

Perception/Annoyance

St-Wellness

Centre



(concrete)

Annoyance (Meditation

Room)


Structural Damage

St.-

Commercial

Bldg

Structural Damage

NOTES

Investigated

Investigated

Investigated

Investigated

Thornhill

Elementary

School

St.-Medical

Clinic

Medical


Sensitive Machinery

St-Medical

Offices

Medical


Condominium Apartment Building

(concrete)

Medical Clinic

Commercial-

Medical


Sensitive Machinery


Structural Damage


Sensitive Machinery

St.-Residential

Bldg

Apartment Building

(concrete)



(concrete)


Structural Damage


Structural Damage

Investigated

Investigated

Investigated

Not Investigated

Investigated

Not Investigated

Not Investigated

St.-RS Kane

Funeral Home

St.-Residential

Bldg

Apartment Building

(concrete)

Arrangement Rooms


Structural Damage

St.-Residential

Bldg

Apartment Building

(concrete)


Structural Damage

Not Investigated

Not Investigated

13


ADDRESS

NATURE OF

BUSINESS



(concrete)

REASON FOR

SENSITIVITY TO

NOISE/VIBRATION


Structural Damage

NOTES

Not Investigated

R53

St.-Toronto

Hydro Bldg

5734 Yonge

St.,Office

Building

The results of the noise and vibration investigations are summarized in Table 4 below:

TABLE 4

MEASURED AMBIENT NOISE AND VIBRATION LEVELS

Receptor No. Name Address

Range of Measured Ambient Levels

Vibration Velocity, dB (ref. 10

-6

in/s)

20-34

Indoor Noise Level, dBA

44

Secondary

School

59-72 36-37

Homes

38-50 32-42

Cemeteries

Archdiocese of

Toronto

20-33 55-62

Dental Clinic

44-53 32-42

Elementary

School

18-60 39-49

Homes

39-46 42-44

R38

Church

Yonge Wellness 7756 Yonge St. 32-42 38

21-51 43-52

School

32-42 60

Reproductive

Medicine

14

Receptor No.

Range of Measured Ambient Levels

Name Address

Vibration Velocity, dB (ref. 10

-6

in/s)

29-41

Indoor Noise Level, dBA

49

Centre

61-76 32-54

R52

Funeral Home

Toronto Hydro 5800 Yonge St. 32-42 41-53 b. Receptors near subway stations, car park lots, subway transformers, ventilation shafts and viaduct crossing

For the purpose of studying the impacts of these sources of noise and vibration associated with the proposed subway line extension, several receptors having wide exposure and close proximity (i.e. worst case receptors) to these sources are selected for impact assessment purposes.

3.3 POTENTIAL SOURCES OF AIR-BORNE NOISE

This section describes the potential sources of environmental (air-borne) noise associated with the subway line. The individual noise assessments are included in Attachment 5.

Bus stations are potential sources of noise when located in the proximity of noise-sensitive buildings.

Certain ancillary facilities will be provided at subway stations in order to facilitate passenger arrivals and departures. The types of facilities proposed include bus platforms, terminals and passenger pick-up/drop off areas. The extents of these facilities are described below:

Steeles Station

- 26 Bus bay terminal underground with bus ramps along Steeles Avenue

- PPUDO area near the north-east corner of Steeles Avenue and Yonge Street with vehicular access to/from Steeles Avenue and Highland Park Drive.

Richmond Hill Station

- Bus terminal (at grade)

- Highway 407 transitway station (under ground)

- PPUDO area (at grade)

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Bus Traffic Data

The AM/PM peak hours bus and car volumes to and from the stations are not available at the present time. Instead, we assumed a headway of 5 minutes per bus and full usage of the car park lots in the PPUDO area.

The following is a summary of the assumed bus and car traffic volumes:

Steeles Station: Bus traffic: ~312 buses (26 bus bays with 5 minute headway for each bus bay during peak hours)

Car traffic: 26 cars idling & 120 cars in and out (no parking)

Richmond Hill Station: Bus traffic: ~624 buses

Car traffic: 52 cars idling & 240 cars in and out (no parking) ii. Commuter Car Park Lot

A commuter car park lot is proposed on the vacant Hydro corridor lands located south north of Longbridge Road, south of Highway 407, east of Yonge Street and west of East

Don River.

The sources of noise associated with the car park lot are car movements along internal routes, car idling at individual lots, car engine start-up noise and car door closing/slamming. iii. Viaduct Crossing

The proposed subway line is expected to run underground through the planned alignment along Yonge Street provided that the grade elevations of the area and Yonge

Street above permit such alignment to go through.

There are also other situations that make it difficult or impossible to run the subway below grade level in particular along river and ravine crossings. In such a case, one of the alternatives is to run the subway line above such low lying areas in a viaduct under

Yonge Street or in an enclosed structure. The viaduct could be constructed using steel or concrete structures.

Noise is emitted as a result of subway trains pass-bys on the viaduct crossing. iv. Electrical Transformer Substations

Electrical power will be fed from the hydro authority to both, the stations and track work.

Noise is emitted from the operation of both the transformer cores and cooling fans.

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v. Ventilation Shafts

There is a potential for hearing subway vehicle noise at the surface from station ventilation fans and ventilation shafts. Noise from ventilation shafts could be significant where the shafts coincide with special trackwork and where the shafts are situated very close to residential units located in quiet areas.

The proposed subway alignment drawings show the locations of several ventilation shafts which are located in proximity to residential buildings along Yonge Street.

3.4 ANALYSIS OF SUBWAY GROUND-BORNE NOISE AND VIBRATION LEVELS

1. Introduction

Operations of subway rail transit system results in ground-borne vibration which is transmitted from the track structure to the adjacent buildings through the intervening geological strata. The vibration of the rail is transmitted through the fastener into the transit structure and the vibration radiated from the structure propagates through the soil to the buildings located close to the subway.

The ground-borne vibration originates at the wheel/rail interface as a result of the vibration generated by the wheels rolling on the rails. Several factors affect the level of vibration including the degree of roughness or smoothness of the wheels and rails, the characteristic dynamics of the transit vehicle and its primary suspension, the speed of the train, the type of track fixation and the type of soil through which the vibration propagates.

The resulting building vibration can cause intrusion either because the mechanical motion is perceptible or because of an audible low frequency rumble caused by the sympathetic vibration of the building walls, ceilings and floors.

In areas where the transit line is in a subway, both ground-borne noise and vibration may be perceptible.

Other important factors which affect the level of generated ground-borne vibration and noise include the presence of switches normally used at crossovers due to the inherent gap and the presence of joints; if any, between adjoining sections of a track.

2. Evaluation of Ground-Borne Noise and Vibration Levels

The evaluation of ground-borne noise and vibration impacts along each segment of the proposed subway is based on actual extensive operational data measured and reported by the TTC and by SS Wilson Associates.

The conducted studies provided valuable data related to the characteristics of the groundborne vibration using information on the wheel/rail interface area relative to the following factors:

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•

Type of subway structure.

•

Type of train and train speed.

•

Geological conditions.

•

Distance from the subway.

•

Noise radiation characteristics of adjacent buildings.

•

Dynamics of the rail/structure and rolling stock.

•

Effects of rail and wheel conditions.

•

Effects of vibration isolation measures.

The following paragraphs summarize the parts of the previous study results which are of interest to this proposed undertaking and which demonstrate the effectiveness of the various investigated vibration control measures: a. The ground-borne vibration and noise from subway train operation has a very narrow band frequency characteristic indicating that the transmission path from the subway trains to the buildings has a filter like characteristic with maximum transmission at about

50 Hz. b. Measurements of ground-borne vibration levels showed that one of the differences in the levels of vibration was the effect of subway structure type. Higher levels were measured adjacent to the lighter weight tunnel structure compared to the concrete double box structure. The results in terms of vibration velocity levels showed these variations to be somewhat insignificant at most of the distances of concern. c. The vibration levels reduce with distance from the tunnel in a normal manner out to 45 metres but then propagate with relatively little further reduction from the 45m to 60m area to about 120m. Beyond 120m the levels then continue to reduce with distance in an expected manner. In terms of velocity levels, the results showed an average reduction of 4 dB per doubling of distance when measured horizontally along the ground and approximately 5.5 to 6 dB per doubling of distance using the actual distance to the rail invert. d. There is generally good correlation between measurements taken on the ground surface and in the buildings and that the vertical vibration levels showed the most consistent and repeatable correlation with in-house sound levels. Of course there are some cases where the building/ground coupling, building structure radiation characteristics, room shape and acoustical absorption could result in some differences from those predicted. The coupling loss or amplification between the buildings and the ground are also dependent on the season of the year or ground condition; e.g. moist or frozen soil. e. The rate of increase in the level of ground-borne vibration due to an increase in train speed is 4 dB for doubling of train speed. f. With regards to ground-borne vibration/noise control, the previous studies also provided the following results:

•

The use of double thickness rail fastener pads results in an overall reduction of 5 to

8 dB in the ground-borne vibration for the lighter weight tunnel structure.

•

The Double Tie System is expected to reduce ground-borne noise and vibration levels by 12 to 14 dB.

18

•

The Continuous Floating Slab is expected to reduce ground-borne noise and vibration levels by 14 to 20 dB. g. The subway train vibration is several orders of magnitude below the vibration levels which causes damage or potential physical damage to buildings.

3. Prediction Model and Results

As the extensive TTC data are available in vibration acceleration levels in 1/1 or 1/3 Octave

Bands and the proposed TTC/MOE vibration criteria are specified in terms of overall vibration velocity re 10

-6

in/s, the TTC data was converted to appropriate vertical vibration velocity levels using a computer model that took into consideration the detailed frequency spectrum of subway train pass-bys.

The TTC data sets were re-analyzed and regression analyses were performed on the entire data sets and also on sub-sets of data for comparison purposes.

The prediction methodology has taken into account the effects of distance, rail discontinuities at crossover and turnout special trackwork, train speed and any vibration control measures. The end result is the estimated vibration levels at the sensitive building or area under consideration which can then be compared to the applicable criteria to determine the acceptability of the ground-borne noise and vibration.

Vibration sensitive land uses (mainly residential properties) are the primary focus of the analysis. In addition, vibration impacts on commercial and institutional properties have also been addressed based on our detailed field examination of the sensitivity of some of these uses.

The analysis is based on 6 car subway trains traveling at a speed of 80 km/h on standard track with standard TTC resilient direct fixation fasteners. Near/at the station areas, maximum speeds of 55/35 km/h have been assumed.

It is important to note that the TTC advises that the resilient track system (double tie) and where required, continuous floating slabs will be used throughout the entire subway alignment.

Table 5 includes the ground-bone vibration and noise analysis, results and assessment of the subway line. The results summarize the projected maximum ground-borne noise and vibration levels from 6 car train pass-bys. Table 5 also shows the applicable ground-borne noise and vibration acceptability criterion, type of structure, distance from the centerline of the nearest set of tracks, expected train speed, distance from the receptor to cross-over switches, and other pertinent information.

Based on the data included in Table 5, it is concluded that there are no adverse groundborne vibration or noise impacts anticipated at all receptors within the study area as a result of the subway line.

19

TABLE 5

20

21

4. Assessment of Ground-Borne Noise and Vibration Impacts

TTC will use a track system such as a double tie and floating slab systems or something equivalent throughout the proposed subway line. This installation will decrease the vibration levels (and consequently reduce the noise levels) by approximately 12 dB which is considered a significant reduction and improvement over the standard rail system. The anticipated 12 dBA decrease in vibration and noise levels was not included in the predicted levels in Table 5.

With reference to the predicted levels listed in Table 5, there are no predicted noise and vibration excesses above the applicable criteria.

Therefore, with the application of the above noted vibration isolation measures, it is our finding that the subway noise and vibration levels will be significantly reduced and that none of the land uses will be exposed to adverse noise and vibration impacts.

22

4.0 CONSTRUCTION NOISE AND VIBRATION IMPACTS

4.1 GENERAL

This section deals with the potential environmental noise and vibration impacts during the construction phase of the proposed undertaking. The sources of noise and vibration may operate above or below ground or within tunnels.

Unlike operational noise, construction noise and vibration are temporary in nature depending on the type of work required and its location relative to the sensitive receptors. A description of the potential receptors has been provided in Tables 3 and 4 and their locations are shown in Figures 5.1 to 5.11.

4.2 SOURCES OF NOISE AND VIBRATION

The primary sources of noise during construction are pile drivers, general excavation, construction activities and vehicular traffic.

The tunneling method using a Tunnel Boring Machine (TBM) is expected to transmit lower levels of noise and vibration to adjacent buildings than the cut and cover method.

However, the cut and cover method will be used for the station structures regardless of the method chosen to construct the running track sections.

The TBM produces steady state variations in the vibration levels each receptor location where the levels gradually rise over a period of a handful of days, remain steady for moreor-less a very limited number of days, following which the levels start to slowly fade away.

The timing of each cycle (2 cycles only during the boring process at each receptor) and the resulting levels depend on the depth of the subway tunnel near the receptor, the lateral distance from the tunnel, the type of soil, the operational characteristics of the TBM and in particular, the thrust being applied by the TBM on the area to be excavated. The presence of high ambient noise due to proximity to major roadways and the internally generated noise inside buildings are also some of the reasons that influence the degree of human audibility of the ground-borne noise due to TBM’s.

In general, except for activities at the access shaft(s) serving the tunnel construction, the general public in urban areas is not likely to be aware of the ongoing tunneling work since

TBM excavation does not produce any audible “environmental” noise at street level.

Community impacts, however, depend on the access shaft(s) locations.

Tunnel construction impacts are concentrated at the shaft(s) and can include the noise due to mobile construction equipment (dozers, loaders, dump trucks, etc.) and more-or-less fixed construction equipment at or near the shaft (cranes, generators, pumps, etc.). The noise generated around the shafts can be controlled using several noise control measures

23

which include physical and administrative controls. The physical measures include the use of fixed and/or temporary sound barrier walls/partial enclosures, traffic management and the use of quieter equipment.

Pile drivers used for construction at the station areas should be of the "quiet" hydraulic type rather than the noisier drop weight type.

One of the sources of concern is the potential impact of "mobilization sites" on the adjoining noise-sensitive land uses as such sites may be the centre for the following activities:

•

Driving

•

Crane operations

•

Construction equipment operated by gasoline, diesel and electric engines

•

Stockpiling of construction materials

•

Removal and stockpiling of excavated materials

•

Areas for truck loading and unloading

•

Parking facilities and other vehicle movements

The significance of the construction noise impact depends on the number of pieces of equipment, their types, time of operation and their proximity to the receptors in question.

For the project under consideration, the existing high ambient sound levels are likely to reduce the significance of the noise during construction although such noise will be clearly audible during peak periods of construction.

One of the effective ways for mitigation of the noise impact due to mobilization sites is to construct an effective sound barrier to protect the residences based on knowledge of the expected construction equipment sound levels and the prevailing ambient noise due to vehicular traffic on nearby roads. Other mitigation measures will also be discussed in the subsequent paragraphs.

4.4 CONTROL OF CONSTRUCTION NOISE

The following is a brief outline of the procedures to be followed in handling construction noise during the Detailed Design and Construction phases: a. Noise sensitive receptors to be identified. b. The applicable municipal noise By-Laws will be examined. Where timing constraints or any other provisions of the municipal by-law may cause hardship to the TTC and its

Contractors, an explanation of this will be outlined in a submission to the MOE and an exemption from such By-Law will be sought directly from the municipality of concern. c. "General noise control measures" (not sound level criteria) will be referred to, or placed into contract documents.

d. Should the TTC or the Contractor receive any complaint from the public, the

24

Contractor’s staff should verify that the "general noise control measures" agreed to are in effect. The Contractor should investigate any noise concerns, the TTC to warn the contractor of any problems and enforce its contract. e. If the "general noise control measures" are complied with, but the public still complain about noise, the TTC should require the contractor to comply with the MOE sound level criteria for construction equipment contained in the MOE's Model Municipal Noise

Control By-Law and the applicable municipal Noise By-laws. Subject to the results of field investigation, alternative noise control measures would be required, where these are reasonably available. f. In selecting the appropriate construction noise control and mitigation measures, the

TTC and the Contractor should give consideration to the technical, administrative, and economic feasibility of the various alternatives.

25

5.0 SUMMARY AND RECOMMENDATIONS

5.1 SUMMARY

This study is carried out to examine all aspects related to the potential noise and vibration impacts of the proposed Yonge Subway line extension on the noise and vibration sensitive receptors located along the subway line and around the bus terminal stations. The study dealt with the documentation of the existing ambient noise and vibration levels by a combination of procedures; actual measurements and/or computer prediction models.

The following potential sources of noise and vibration are addressed in the study: a. Underground subway vehicle movements ground-borne noise and vibration b. Bus stations noise c. Commuter car park noise d. Subway viaduct crossing noise e. Electrical transformer substations noise f. Ventilation shafts noise

The following are our conclusions itemized for each potential source of noise and vibration addressed in this study:

Subway Ground-Borne Noise and Vibration a) Five receptors are selected (namely R11, R15, R28, R29 & R34) to represent the low and medium residential dwelling units having essentially similar exposure to the proposed subway line noise and vibration levels. The distance setback from these dwelling units to the subway alignment range from 15 to 55m. The predicted noise and vibration levels are considered well below the MOE/TTC Protocol criteria. In summary, while the impact rating is expected to be “no impact”, it is quite possible that during certain hours of the night and during street traffic lulls, that the subway noise may be barely to just audible due to the expected amplification of the wood frame construction of the vibration signal. b) Sixteen receptors are selected (namely R1, R5, R7, R14, R18, R19, R20, R21, R24,

R39, R44, R46, R47, R49, R50 & R510) to represent residential apartment buildings having exposure to the subway line. The distance setback from the subway alignment range from 25 to 65m. The predicted noise and vibration levels are also below the applicable criteria. With potential building decoupling, it is expected that the predicted levels would be lower than actually projected outside. c) Twenty six receptors are selected (namely R2, R4, R6, R8, R9, R10, R12, R13, R16,

R17, R22, R23, R25, R27, R32, R33, R36, R37, R38, R40, R42, R43, R45, R48, R52 &

R53) to represent commercial buildings in the study area. The distance setback from these buildings to the subway alignment range from 15 to 75m. Although the closest

26

point to the subway was used for assessment purposes, it must be noted that not all the units, rooms or spaces will be affected due to the large size of such buildings. The predicted noise and vibration levels are also at or below the applicable criteria. d) Six receptors are selected (namely R3, R26, R30, R31, R35 & R41) to represent institutional (religious and educational) buildings. Due to the potential sensitivity of these institutional land uses, the applicable criteria selected are the most restrictive one to represent fairly sensitive buildings that may host noise and vibration sensitive activities/processes. The distance setback from these buildings to the subway alignment ranged from 20 to 70m. In all cases, it is important to note that the closest distance to the building was used as the entry point for noise and vibration into the building, at which the noise and vibration levels were calculated. The predicted noise and vibration levels are also at or below the applicable criteria.

The results of the noise and vibration predictions were adjusted to account for the use of railway vibration isolation such as using the double tie system and the use of floating slabs throughout the entire system with the application of a reasonable reduction factor of 12 dB to the vibration levels. In summary, it is our conclusion that there will be no impact for all selected points of reception.

Bus Stations

The two bus stations (Steeles and Richmond Hill) will have no impacts on residential land uses due to a combination of distance setbacks and high ambient noise levels due to existing traffic.

Commuter Car Park Lot

The car park lot between Yonge Street and the East Don River and between Highway 407 and Longbridge Road will have an adverse noise impact on the Longbridge Road residences. With the use of the recommended south property line 6m high sound barrier

(2m base berm plus 4m noise wall atop), the noise impact will be mitigated to pre-existing ambient conditions.

Subway Viaduct Crossing

The subway viaduct crossing over the East Don River is predicted to have significant noise impacts at the adjacent golf course and at the nearby residential properties if steel or open concrete viaduct structures are used. The application of several noise control measures would result in significant acoustic improvements. Enclosing the subway line in a concrete structure would certainly eliminate the concerns with a predicted outside sound level within the low to mid 50’s dBA which will blend with the outside ambient due to traffic.

27

Construction Noise and Vibration

The preliminary analysis of the noise during the construction phase indicates the potential for concern in the residential and/or industrial area adjacent to possible construction mobilization sites and possibly due to the use of the Tunnel Boring Machines (TBM) in proximity to a limited number of buildings.

5.2 MITIGATION

1. A track system, such as a double tie and floating slab systems or something equivalent will be installed in all sections of the subway line in order to reduce the ground-borne vibration and noise created by the train movements.

2. TTC will continue to follow their practices of their routine maintenance of train wheels to eliminate “wheel flats” based on their practice of remote “wheel flats” monitoring stations.

3. A 6.0m high sound barrier (2m high base berm plus 4m high nose wall atop) will be constructed along the south side of the commuter car park lot (located on the hydro lands south of Highway 407 on the east side of Yonge Street) with a sound absorptive face treatment on the south side of the wall facing the residences to reduce the effect of acoustic reflections.

4. Several measures (use of subway track isolation, reducing the size of viaduct openings; application of suitable sound absorbing surface finish materials to the interior sides and use of a concrete instead of steel viaduct structure) could be applied to the subway viaduct crossing over the East Don River if the sides of the bridge are to remain open. The sound absorbing material should have fairly high sound absorption co-efficient and be applied on the underside of the ceiling and on the inner sides of the viaduct parapet walls.

Enclosing the subway line in a concrete structure is considered the best noise control alternative as it would eliminate the concerns with a predicted outside sound level within the low to mid 50’s dBA which will blend with the outside ambient due to traffic.

5. Recommended noise control measures for the subway transformer substations include one or a combination of the following:

Specifying low sound emission transformer system, for example:

¾ Transformers core: maximum 59 dBA @ 15m

¾ Cooling fans: maximum 64 dBA @ 15m

Partial sound barriers or enclosures

Orientation of the equipment and structures

6. Acoustical treatment of ventilation shafts. The acoustical treatment may involve

28

the use of lined turns and bends, partial barriers/enclosure near the ground surface and the application of special sound absorbing material to the inside walls of the shaft. The issue of noise in this case is considered as a routine technical matter for detailed design purposes.

Locating ventilation fans near the tracks rather than at street level can also help if there are turns in the shafts. This is also considered as a routine technical design factor.

7. Further noise assessment to be undertaken for the following potential sources of noise during the detail design phase: a. Bus stations b. Commuter car park c. Subway viaduct crossing

8. The following is a summary of the potential stationary sources of noise that will require functional and detail design with one of the objectives to obtain Provincial approval and Certificates of Approval under the authority of the EPA:

Ventilation shafts serving station boxes and associated HVAC equipment

Fire ventilation shafts and associated HVAC equipment

Ventilation shafts with grating at grade and associated HVAC equipment

Diesel work-car ventilation fan modes

Equipment that serves Emergency Exit Buildings

HVAC equipment associated with subway and/or bus stations

Electrical substations that feed the subway

9. The proponent will enforce and monitor noise and vibration during construction in accordance with the City of Toronto Noise By-Law (Chapter 591), City of

Toronto By-Law No. 514-2008 with respect to regulation of vibrations from construction activity, Town of Markham Noise By-Law (2003-137), City of

Vaughan Noise By-Law (96-2006) and the Town of Richmond Hill Noise By-Law

(Chapter 1005).

29

FIGURES

30

FIGURE 4.1

SUBWAY LINE PROFILE

35

FIGURE 4.2


36

FIGURE 4.3


37

FIGURE 4.4


38

FIGURE 4.5


39

FIGURE 4.6


40

FIGURE 4.7


41

FIGURE 4.8


42

FIGURE 4.9


43

ATTACHMENT 1

GLOSSARY

55

GLOSSARY

A weighted decibel; dBA A nationally and internationally standardized frequency weighting applied to the sound level (measured in decibels) spectrum to approximate the sensitivity of the human hearing mechanism as a function of frequency (pitch).

Airborne Sound is sound that reaches the point of interest by propagation through air.

Ambient/ Background Sound Level is the all-encompassing noise associated with a given environment and comprises a composite of sounds from many sources, other than the source of interest, near and far . In the context of this document, the ambient or existing noise level is the noise level which exists at a receptor as a result of existing traffic conditions without the addition of noise generated by the proposed undertaking or the new source of noise.

A-Weighted sound level The “A-weighted sound level” is a sound pressure level indicated by a measurement system that includes an A-weighted network. The resulting value is in decibels and commonly labelled dBA .

A-Weighting is a frequency weighting intended to approximate the relative sensitivity of the normal human ear to different frequencies (pitches of sound) .The specific variation of sensitivity with frequency to conform to IEC Publication 651. dBA means the A-weighted sound pressure level.

Decibel is the common measure of sound level or sound pressure level. It is the term to identify 10 times the common logarithm of the ratio of two like quantities proportional to power or energy. The “decibel” is a dimensionless measure of sound level or sound pressure level; see sound pressure level.

Environmental Noise is noise transmitted through the outdoor environment as opposed to noise generated and contained within buildings.

Equivalent Sound Pressure Level denoted Leq is the level of a steady sound having the same time integral of the squared sound pressure, in the measurement interval, as the observed sound.

Indoor sound level is an estimated/calculated sound level in the central part of a room.

L eq

– The Energy Equivalent Continuous Sound Level is the constant sound level over the time period in question, that results in the same total sound energy as the

56

actually varying sound. It must be associated with a time period. Leq is a measure of total sound energy dose over a specified time period.

Leq (T): Leq (16 hours), Leq (8 hours), Leq (1 hours) means the A-weighted level of a steady sound carrying the same total energy in the time period T as the observed fluctuating sound. The time period T is given in brackets.

Noise is defined as any unwanted sound.

Noise Sensitive Land Use means a land use that is sensitive to noise, whether inside and/or outside the property and that must be planned and/or designed using appropriate land use compatibility principles. Examples of sensitive land uses:

•

residential

•

seasonal residential developments;

•

hospitals, nursing/retirement homes, schools, day-care centres;

•

other land uses that may contain outdoor and/or outdoor areas/spaces where an intruding noise may create an adverse effect.

In general, a noise-sensitive land use could be any type of land use where environmental noise is likely to cause an adverse effect or material discomfort whether inside or outside of a building.

Point of Reception means any point on the premises of a person where sound or vibration originating from other than those premises is received. For the purposes of noise impact assessment in the plane of a bedroom window, the point of assessment is typically 4.5 m above ground unless the dwelling is a multi-storey building. The point of reception is commonly used for assessment of stationary sources of noise

Sound is a fluctuation in pressure, particle displacement or particle velocity propagated in any medium; or the auditory sensation that may be produced by it.

Sound (Pressure) Level is the logarithmic ratio of the instantaneous energy of a sound to the energy at the threshold of hearing. It is measured in decibels (dB)

Sound Level is the A-weighted sound pressure level in dBA.

Stationary Source of Noise For the purpose of this document, a stationary source of noise is defined as: “Stationary source means all sources of sound/vibration; whether fixed or mobile, that exist/operate on the premises, property or facility, the combined sound/vibration levels of which are emitted beyond the property boundary of the premises, property or facility, unless the source(s) is (are) due to temporary

“construction” as defined in the applicable municipal noise “By-Law”.”

Time Periods (MOE predefined time periods ) " Day-time " is the 16-hour period between 07:00 and 23:00 hours. " Evening " is the 4-hour period between 19:00 and

57

23:00 hours. " Night-time " is the 8-hour period between 23:00 and 07:00 hours.

Vibration is a temporal and spatial oscillation of displacement, velocity or acceleration in a solid medium .

58

ATTACHMENT 2

SOUND AND VIBRATION LEVEL CRITERIA

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

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ATTACHMENT 3

ROAD TRAFFIC DATA

81

ATTACHMENT 4

CALCULATIONS

137

STAMSON 5.0 SUMMARY REPORT Date: 11-12-2008 13:40:31

MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT

Filename: section 1.te Time Period: Day/Night 16/8 hours

Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback - (Finch Avenue. to Hendon Avenue)

Road data, segment # 1: Yonge Street (day/night)

------------------------------------------------

Car traffic volume : 52397/5822 veh/TimePeriod *

Medium truck volume : 1092/121 veh/TimePeriod *

Heavy truck volume : 1092/121 veh/TimePeriod *

Posted speed limit : 50 km/h

Road gradient : 0 %

Road pavement : 1 (Typical asphalt or concrete)

* Refers to calculated road volumes based on the following input:

24 hr Traffic Volume (AADT or SADT): 49750

Percentage of Annual Growth : 2.00

Number of Years of Growth : 10.00

Medium Truck % of Total Volume : 2.00

Heavy Truck % of Total Volume : 2.00

Day (16 hrs) % of Total Volume : 90.00

Data for Segment # 1: Yonge Street (day/night)

----------------------------------------------

Angle1 Angle2 : -90.00 deg 90.00 deg

Wood depth : 0 (No woods.)

No of house rows : 0 / 0

Surface : 2 (Reflective ground surface)

Receiver source distance : 15.00 / 15.00 m

Receiver height : 1.50 / 4.50 m

Topography : 1 (Flat/gentle slope; no barrier)

Reference angle : 0.00

Result summary (day)

--------------------

! source ! Road ! Total

! height ! Leq ! Leq

! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.42 ! 71.42

--------------------+---------+---------+---------

Total 71.42 dBA

Result summary (night)

----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 64.88 ! 64.88

--------------------+---------+---------+---------

Total 64.88 dBA

TOTAL Leq FROM ALL SOURCES (DAY): 71.42

(NIGHT): 64.88

138



Filename: section2.te Time Period: Day/Night 16/8 hours

Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback (Hendon Avenue to Drewry Avenue)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.54 ! 71.54

--------------------+---------+---------+---------

Total 71.54 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 65.01 ! 65.01

--------------------+---------+---------+---------

Total 65.01 dBA


(NIGHT): 65.01

139




Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback (Drewry Avenue to Patricia Avenue)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.90 ! 71.90

--------------------+---------+---------+---------

Total 71.90 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 65.36 ! 65.36

--------------------+---------+---------+---------

Total 65.36 dBA


(NIGHT): 65.36

140




Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback (Patricia Avenue to Moore Park Avenue)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.82 ! 71.82

--------------------+---------+---------+---------

Total 71.82 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 65.29 ! 65.29

--------------------+---------+---------+---------

Total 65.29 dBA


(NIGHT): 65.29

141




Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback (Moore Park Avenue to Steeles Avenue West)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.60 ! 71.60

--------------------+---------+---------+---------

Total 71.60 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 65.06 ! 65.06

--------------------+---------+---------+---------

Total 65.06 dBA


(NIGHT): 65.06

142




Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback (Steeles Avenue West to Highland Park Boulevard)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.53 ! 71.53

--------------------+---------+---------+---------

Total 71.53 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 64.99 ! 64.99

--------------------+---------+---------+---------

Total 64.99 dBA


(NIGHT): 64.99

143




Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback(Highland Park Boulevard to Centre Street)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.92 ! 71.92

--------------------+---------+---------+---------

Total 71.92 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 65.38 ! 65.38

--------------------+---------+---------+---------

Total 65.38 dBA


(NIGHT): 65.38

144




Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance setback (Centre Street to High Tech Road)


------------------------------------------------





Road gradient : 0 %










----------------------------------------------










--------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 71.20 ! 71.20

--------------------+---------+---------+---------

Total 71.20 dBA


----------------------



! (m) ! (dBA) ! (dBA)

--------------------+---------+---------+---------

1.Yonge Street ! 1.19 ! 64.66 ! 64.66

--------------------+---------+---------+---------

Total 64.66 dBA


(NIGHT): 64.66

145

ATTACHMENT 5

SPECIFIC NOISE ASSESSMENTS

146

Bus Stations

Bus stations are potential sources of noise when located in the proximity of noisesensitive buildings.

Certain ancillary facilities will be provided at subway stations in order to facilitate passenger arrivals and departures. The types of facilities proposed include bus platforms, terminals and passenger pick-up/drop off areas. The extents of these facilities are described below.

Steeles Station

- 26 Bus bay terminal underground with bus ramps along Steeles Avenue

- PPUDO area near the north-east corner of Steeles Avenue and Yonge Street with vehicular access to/from Steeles Avenue and Highland Park Drive.

Richmond Hill Station

- Bus terminal (at grade)

- Highway 407 transitway station (under ground)

- PPUDO area (at grade)

The nearest noise sensitive areas to the Steeles Station are the single family homes along Highland Park Boulevard (receptor La) and the single family homes along south side of Steeles Avenue (receptor Lb). The nearest noise sensitive areas to the Richmond Hill Station are the high-rise apartment building on High Tech Road

(receptor Lc). Figures A and B show the locations of receptors La, Lb and Lc.

In order to predict the future sound levels due to the above-noted bus stations, we relied on the stationary sources noise calculation model developed by SS Wilson

Associates to handle complex evaluations described below.

Sound Level Prediction Model for Bus Terminals

A 3-D computer program for multiple point and line sources and multiple receivers was used to calculate the bus stations sound levels. The program takes into account:

•

Reference sound levels and reference distances for the bus moving, idling and accelerating within stations, i.e. sound emission levels.

•

The Cartesian co-ordinates (x, y & z) of all sources and receivers.

•

The number of buses in a given time period and the duration of each event.

•

Spherical divergence factor.

•

Additional attenuation due to sound barriers; natural or man-made types

(none was assumed).

•

Additional attenuation due to ground (as modified by sources/receiver

147

elevations, the presence of intervening barriers and the type of ground). The ground cover was assumed to be reflective in this case.

•

Atmospheric attenuation due to air molecular absorption.

Bus and Road Traffic Data

Attachment 3 includes the road traffic data provided by MRC pertaining to the background vehicular traffic on the nearby municipal arterial roads.

With regards to AM/PM peak hours bus and car volumes to and from the stations, we assumed a headway of 5 minutes per bus and full usage of the car park lots in the PPUDO area.

The following is a summary of the bus and traffic volumes:

Steeles Station: Bus traffic: ~312 buses

Car traffic: 26 cars idling & 120 cars in and out

Richmond Hill Station: Bus traffic: ~624 buses

Car traffic: 52 cars idling & 240 cars in and out

Results

The following Tables A and B contain a summary of the predicted ambient and bus station sound levels as well as impact assessment. Sample calculations are included in Attachment 4:

TABLE A

STEELES BUS STATION

Worst Case

Selected

Receptor Code

Predicted

Bus Station

Noise

Leq 1 hr.

57 dBA

Predicted

Ambient

Noise

Leq 1 hr.

59 dBA

Predicted

Excess

Sound Level

--

Significance of the Noise

Impact nil

House on

Highland Park

Boulevard (La)

House on

Steeles Avenue

(Lb)

63 dBA 70 dBA -- nil

148

Worst Case

Selected

Receptor

Code

Apartment

Building on

High Tech

Road (Lc)

TABLE B

RICHMOND HILL BUS STATION

Predicted

Bus Station

Noise

Leq 1 hr.

66 dBA

Predicted

Ambient

Noise

Leq 1 hr.

67 dBA

Predicted

Excess

Sound Level

--

Significance of the Noise

Impact nil

From the above tables, the following is concluded:

Steele Bus Station : No noise impacts are predicted at the nearby residences along Highland Park Boulevard and Steeles Avenue. The station impact is further lessened by the presence of high ambient noise due to Steeles Avenue and by the significant reductions in the bus station traffic during the off-peak hours.

Richmond Hill Bus Station : No noise impact is predicted at the residential apartment building located on High Tech Road due. The station impact is further lessened by the presence of high ambient noise due to High Tech Road,

Highway 407 and Highway 7 and by the significant reductions in the bus station traffic during the off-peak hours.

Support sound level calculations are attached.

149

FIGURE A

STEELES STATION

150

La

Lb

Richmond Hill Station

FIGURE B

RICHMOND HILL STATION

151

Lc

COMMUTER CAR PARK LOT

It is our understanding that the area residents located along Longbridge Road (a total of 31 residences along the north side of Longbridge Road) are concerned about the potential noise impact due to the proposed construction of a commuter car park lot on the vacant lands located between these residential homes and

Highway 407 right-of-way.

Figure C illustrates the subject area showing the transportation sources of noise;

Highway 407 and Highway 7, Yonge Street and the vacant land being proposed for TTC subway extension car park lot.

The following paragraphs provide a summary of the investigation conducted to assess the significance of the potential noise impact.

1. Sources of Ambient Noise and Their Significance

The major source of ambient noise reaching the homes located along

Longbridge Road is Highway 407

1

and to a lesser extent, traffic along

Highway 7. For the purposes of this study, the noise from Yonge Street was ignored since it only affects a small number of homes on the east side of

Longbridge Road.

Presently, the homes are exposed to certain sound levels from the abovenoted sources. These ambient/background levels are of importance for undertaking this assessment. Accordingly, actual long-term sound level measurements were taken at three selected house locations. Figure C also illustrates the location of the selected receptors.

Precision Sound Level Meters (Model: Rion NL-22) were placed in the backyards of the three noted homes to take actual ambient sound level readings from October 29 to November 3, 2008 , the results of which are included in Tables C, D & E and are shown in Figures D.1 & D.2.

From the measured sound levels, the following is an extracted summary

(energy average of three days) of the Leq sound level descriptor specified by the Ministry of the Environment (MOE) for impact assessment purposes during the daytime (i.e. from 7am to 11pm) over the 3 noted days measured at the noted locations:

Receptor location Ld: Leq16 hr 59 dBA

Receptor location Le: Leq16 hr 59 dBA

1

For the purposes of this study, an assumption was made that Highway 407 traffic between Bathurst Street and Yonge Street is approximately 109,600 vehicles per day with 6% heavy trucks and 6% medium trucks based on the best available data from York Region.

152

Receptor location Lf: Leq16 hr 60 dBA

The above measured sound levels do include the beneficial acoustic effects of the existing ground cover (green field).

2. Impact Assessment Methodology

Presently, the subject area is experiencing a beneficial acoustic attenuation factor related to the existing type of ground which is composed of vegetation, grass and small shrubs. Such ground cover attenuates Highway 407 and

Highway 7 noise over and above the expected attenuation due to increased distance. The introduction of the parking lot may negate the beneficial effect of this type of ground cover as a result of the proposed hard reflecting surfaces. Accordingly, in order to study this effect, it was found necessary to evaluate the expected loss of ground attenuation as a result of the proposed construction of the parking lot. This factor is considered as the most pronounced potential negative effect on the noted homes as explained in the next sections.

The other additional potential negative effect of less significance due to the proposed parking is the future vehicular traffic movements within the parking lot, especially during am and pm peak activity hours. Figures E, F & G illustrate conceptual sections through the Hydro property to illustrate the noise propagation concepts

3. Sound Level Prediction Methodology

As stated earlier, the actual sound level readings from Highway 407 and

Highway 7 were measured at 3 locations which were then used to conduct a simulation of the same scenario with and without the effect of the existing ground cover. An MOE noise prediction model was used to simulate the current situation and a worst case situation involving no ground attenuation

(i.e. the parking lot). Sample calculations are attached.

The following is a summary of the predicted Leq16 sound levels with the effects of the existing ground cover at the selected receptors based on the best available traffic data on Highway 407:

Receptor Location Ld: Leq16 hr 60 dBA

Receptor Location Le: Leq16 hr 59 dBA

Receptor Location Lf: Leq16 hr 59 dBA

From the above predictions, it is our finding that the actually measured sound levels are in close agreement (± 1 dBA) with the predicted sound levels with the effects of the ground cover.

153

In addition to Highways 407 and 7 and for the purposes of this assessment, a further assumption was made that approximately 200 vehicles within the parking lot would pass by during each hour on a driveway located approximately 30 meters away from the subject homes.

The following is a summary of the predicted Leq sound levels at the same receptor locations if the intervening lands are assumed to be hard reflecting; i.e. simulates a parking lot without noise control measures:

Receptor Location Ld: Leq16 hr 68 dBA

Receptor Location Le: Leq16 hr 67 dBA

Receptor Location Lf: Leq16 hr 67 dBA

From the calculations, it is our finding that the ground attenuation factor as a result of the existing vegetation ground cover is approximately 8 dBA which is considered an acoustically significant beneficial factor.

4. Proposed Noise Control Measures

In order to maintain the present relatively low noise environment in the subject area, we are recommending that consideration be given to the use of a south property line sound barrier across the entire length to provide sound level reduction to offset the potential increase in the existing ambient noise as a result of the introduction of the proposed parking lot.

One of the positive technical features in the subject area is the fact that all of the homes located south of the parking lot are of the single-family bungalow type, thus making the sound barriers acoustically effective for the control of the outdoor and indoor sound levels.

According to the information provided by the Study Team, a strip of land approximately 10 meters wide will be allocated for construction of a physical separation, a sound barrier as well as a pedestrian walkway immediately north of the north property line of the subject homes. On the assumption that the walkway would take approximately 2 m wide, the remaining 8m could be used for construction of a base berm with a sound barrier wall located on top of the berm.

In order to investigate the acoustic efficiency of such a sound barrier, additional sound level predictions were made using the MOE, the results of which indicate the following expected sound level attenuation factors depending on the barrier height:

3.0 m high barrier: Leq16 hr 64 dBA



154





Based on our findings, a 6m high sound barrier (a 2m base berm with a 4m high noise wall atop) located along the joint property line will result in an Leq

59 dBA which is acoustically comparable with the existing ambient sound levels currently experienced by the residents of the subject area. In other words, it is predicted that there will be no negative acoustic impact from the proposed parking lot.

Since final grading plans are not available at this stage, the barrier height is based on the assumption that the ground elevations at the road, the base of the barrier and the receiver are all equal until such time as the grading plans become available.

Accordingly, the sound barrier calculations should be revisited during the detail design stage to define specific barrier alignments and heights based on the final grading plans

Figure H shows photographs of typical sound barrier arrangements using different barrier materials and Figure I illustrates the proposed sound barrier alignment.

Another beneficial factor from this sound barrier construction is that it will provide significant sound level reductions due to other activities in the proposed parking lot, such as car engine start-up noise, car door closing/slamming, etc.

155

Day

1

2

3

4

5

TABLE C

MEASURED AMBIENT SOUND LEVELS

14 LONGBRIDGE ROAD (Lf)

SSWA RION NL-22 Unit A

From - To Period

Period

Leq

MOE

Descriptor

00:00:00 AM- 7:00:00 AM Night 75.0

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 73.2

11:00:00 PM-00:00:00 AM Night Leq night 8Hrs

00:00:00 AM- 7:00:00 AM Night 55.5

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 61.2


00:00:00 AM- 7:00:00 AM Night 56.5

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 60.4


00:00:00 AM- 7:00:00 AM Night 58.0

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 63.2


00:00:00 AM- 7:00:00 AM Night 57.9

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 73.7

11:00:00 PM-00:00:00 AM Night Leq night 8Hrs dBA

73

74

61

56

60

57

63

58

74

67

156

Day

1

2

3

4

5

TABLE D


28 LONGBRIDGE ROAD (Le)

SSWA RION NL-22 Unit G


Period

Leq

MOE

Descriptor

00:00:00 AM- 7:00:00 AM Night #NUM!

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 66.2


00:00:00 AM- 7:00:00 AM Night 59.7

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 60.7


00:00:00 AM- 7:00:00 AM Night 54.3

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 62.4


00:00:00 AM- 7:00:00 AM Night 56.1

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 57.2


00:00:00 AM- 7:00:00 AM Night 54.8

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 58.0


66 n/a

61

60

62

55

57

56

58 n/a

157

Day

1

2

3

4

5

TABLE E


44 LONGBRIDGE ROAD (Ld)

SSWA RION NL-22 Unit C


Period

Leq

MOE

Descriptor

00:00:00 AM- 7:00:00 AM Night

7:00:00 AM-11:00:00 PM Day

0.0

Leq day 16 Hrs

61.8


00:00:00 AM- 7:00:00 AM Night 56.8

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 59.2


00:00:00 AM- 7:00:00 AM Night 55.3

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 62.4


00:00:00 AM- 7:00:00 AM Night 55.1

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 57.4


00:00:00 AM- 7:00:00 AM Night 52.6

Leq day 16 Hrs

7:00:00 AM-11:00:00 PM Day 58.0


62

46

59

57

62

56

57

55

58

52

158

N

TYPICAL- NOISE IMPACT

ASSESSMENT LOCATION Ld

(44 LONGBRIDGE ROAD)


ASSESSMENT LOCATION Le



ASSESSMENT LOCATION Lf


FIGURE C: THE SUBJECT AREA AND THE SELECTED RECEPTOR LOCATIONS

TYPICAL- PROPOSED

PARKING LOT AREA

159

SS WILSON ASSOCIATES, PROJECT: ……………………………., LOCATION: …………………………………..15 MINUTE INTERVALS SOUND LEVELS

80

75

70

65

60

55

50

45

40

TIME @ 15 MINUTE INTERVALS

Leq Lmax Lmin L01 L50 L90

FIGURE D.1: MEASURED EXISTING AMBIENT SOUND LEVELS AT LOCATION

Ld (OCTOBER 29 TO NOVEMBER 3, 2008)

SS WILSON ASSOCIATES, PROJECT: ……………………………., LOCATION: …………………………………..15 MINUTE INTERVALS SOUND LEVELS

80

75

70

65

60

55

50

45

40

35

30

TIME @ HOURLY INTERVALS

Hourly Leq Sound Level, dB Leq Day & Night

FIGURE D.2: SUMMARY OF MEASURED EXISTING HOURLY AMBIENT SOUND

LEVELS AT LOCATION Ld (HOURLY AND DAILY DATA)

160

TYPICAL

RECEPTOR

LOCATION

MEASURED EXISTING

DAYTIME SOUND LEVEL:

Leq 59 dBA

EXISTING SOUND ABSORBING

GROUND COVER (VEGETATION)

DIRECT LINE-OF-SIGHT FROM

THE NOISE SOURCE TO A

RECEPTOR INCLUDING GROUND

ATTENUATION

FIGURE E: CONCEPTUAL SECTION THROUGH THE EXISTING

PREDICTED DAYTIME SOUND

LEVEL WITH THE PARKING

LOT: Leq 68 dBA

AREA

ADDITIONAL REFLECTED

SOUND AND LOSS OF GROUND

ATTENUATION



FIGURE F: CONCEPTUAL SECTION THROUGH THE PROPOSED PARKING AREA

TYPICAL- TRAFFIC ON

HWY 407



TYPICAL- TRAFFIC ON

HWY 407

161

PROPOSED SOUND BARRIER

ALONG THE JOINT PROPERTY LINE

2.0m BASE BERM + 4.0m NOISE

WALL ATOP

TYPICAL- TRAFFIC ON HWY

407

FIGURE G: CONCEPTUAL SECTION THROUGH THE PROPOSED PROPERTY LINE SOUND BARRIER

FIGURE H: TYPICAL SOUND BARRIERS

162

N

TYPICAL PROPERTY LINE

SOUND BARRIER

ALIGNMENT

FIGURE I: SOUND BARRIER ALIGNMENT

163



Filename: hwy407.te Time Period: 24 hours

Description: Current Sound Levels at Receptor Ld

Road data, segment # 1: Hwy 407

-------------------------------

Car traffic volume : 96448 veh/TimePeriod *

Medium truck volume : 6576 veh/TimePeriod *

Heavy truck volume : 6576 veh/TimePeriod *


Road gradient : 2 %


Data for Segment # 1: Hwy 407

-----------------------------



No of house rows : 0

Surface : 1 (Absorptive ground surface)

Receiver source distance : 280.00 m

Receiver height : 2.00 m



Result summary

--------------



! (m) ! (dBA) ! (dBA)

--------------------+----------+----------+----------

1.Hwy 407 ! 1.57 ! 60.13 ! 60.13

--------------------+----------+----------+----------

Total 60.13 dBA

TOTAL Leq FROM ALL SOURCES: 60.13

164

STAMSON 5.0 NORMAL REPORT Date: 28-01-2009 15:23:47


Filename: hwy40766.te Time Period: 24 hours

Description: Current Sound levels without Absorptive Ground Surface at

Receptor Ld


-------------------------------





Road gradient : 2 %



-----------------------------









Results segment # 1: Hwy 407

----------------------------

Source height = 1.57 m

ROAD (0.00 + 69.73 + 0.00) = 69.73 dBA

Angle1 Angle2 Alpha RefLeq P.Adj D.Adj F.Adj W.Adj H.Adj B.Adj

SubLeq

------------------------------------------------------------------------

----

-90 90 0.00 82.44 0.00 -12.71 0.00 0.00 0.00 0.00

69.73

------------------------------------------------------------------------

----

Segment Leq : 69.73 dBA

Total Leq All Segments: 69.73 dBA


165



Filename: hwy407b.te Time Period: 24 hours

Description: Sound barrier required to keep sound levels at existing conditions at Receptor Ld


-------------------------------





Road gradient : 2 %



-----------------------------







Topography : 2 (Flat/gentle slope; with barrier)

Barrier angle1 : -90.00 deg Angle2 : 90.00 deg

Barrier height : 6.00 m

Barrier receiver distance : 22.00 m

Source elevation : 0.00 m

Receiver elevation : 0.00 m

Barrier elevation : 0.00 m


Road data, segment # 2: Parking Lot

-----------------------------------

Car traffic volume : 2400 veh/TimePeriod

Medium truck volume : 0 veh/TimePeriod

Heavy truck volume : 0 veh/TimePeriod


Road gradient : 0 %


Data for Segment # 2: Parking Lot

---------------------------------







Topography : 2 (Flat/gentle slope; with barrier)

Barrier angle1 : -90.00 deg Angle2 : 90.00 deg

Barrier height : 6.00 m

Barrier receiver distance : 22.00 m

Source elevation : 0.00 m

Receiver elevation : 0.00 m

Barrier elevation : 0.00 m


Result summary

--------------

166



! (m) ! (dBA) ! (dBA)

--------------------+----------+----------+----------

1.Hwy 407 ! 1.57 ! 59.02 ! 59.02

2.Parking Lot ! 0.50 ! 30.50 ! 30.50

--------------------+----------+----------+----------

Total 59.03 dBA


167

SUBWAY VIADUCT

Introduction

The proposed subway line is expected to run underground through the planned alignment along Yonge Street provided that the grade elevations of the area and/or the roads above permit such alignment to go through. There are also other situations that make it difficult or impossible to run the subway line below grade level in particular along river and ravine crossings.

In such a case, one of the alternatives is to run the subway line above such low lying areas in a viaduct under the road or in an enclosed structure.

The objective of this section is to address the noise impact potential due to subway train movements in a viaduct under a roadway bridge crossing over the East Don River in

Thornhill.

Figure J illustrates the area where the subway line may run through a viaduct/bridge over the East Don River and Figure K is the proposed construction staging.

From the noise impact viewpoint only, the most likely preferred alternative for crossing the subject area will be through a totally enclosed concrete viaduct structure. This is based on our finding from a similar concrete viaduct structure in the Sheppard subway line crossing near Leslie Street where subway train noise is barely audible in close proximity to the enclosed concrete structure. As one moves away from the structure, the subway trains pass-by noise become hardly audible. Therefore, if the final decision is to enclose the viaduct under the Yonge Street crossing over the East Don River, then there will be no potential for noise impact on any receptor in the area.

In the following paragraphs, we are providing the Study Team with more detailed information on the implication of using other alternative design options for the viaduct structure.

Figure L is an artist rendering of the subway viaduct under the proposed Yonge Street bridge.

Sound Levels Due to Subway Train Pass-By in a Viaduct

The closest example of a viaduct structure is the Bloor-Danforth subway line where the subway runs in a steel structure suspended under the Bloor Street East/Danforth

Avenue concrete bridge crossing over the Don River.

Figure M illustrates an aerial view of the Bloor Viaduct and the approximate location of the planned sound measurement position.

Photographs 1.a to 1.d illustrate the existing Bloor viaduct and Photographs 2.a to 2.d

168

illustrate the noise measurements arrangements.

The measurement position was located at an approximate distance of 30m to the closest east-bound subway path at an approximate vertical distance separation of 4 to

5m below the subway in order to reduce the effect of vehicular traffic noise on Bloor

Street.

The measurements were taken with a Precision Sound Level Analyzer, RION NA-28, which was calibrated with a precision sound level calibrator, B&K 4132. The pass-by data of several subway trains were recorded and later analyzed.

The measurements were taken when the train entered and left the most westerly 50m bridge span where the noise signal was taken within such distance.

Figure N.1 illustrates summary of the measured sound levels for several subway train pass-bys with a consistent maximum sound level (L max

) average of 83 dBA at 30m and

Leq of approximately 78 dBA at 30m.

For comparison of subway trains moving in a steel structure viaduct with subway train movements on flat ground, reference should be made to Figure N.2 which illustrates a comparison between the frequency spectra of both cases. The results show that the steel structure is measured to produce 13 dBA higher noise, which is considered

“acoustically significant”.

The following is a summary of our predicted reference sound emission levels of all possible subway alternatives for further impact assessment purposes:

Steel viaduct structure (similar to Bloor Viaduct)

No viaduct-movements on flat ground

Totally enclosed (in concrete) viaduct structure (similar to Sheppard E/Leslie St.)

Open concrete viaduct

: Leq day

78 dBA @ 30m

: Leq day

65 dBA @ 30m

2

: Leq 53 dBA @ 30m

: Leq day

75 dBA @ 30m

Impact Assessment

Presently, there are several noise-sensitive receptors located on the east and west sides of the potential viaduct subway crossing which include low, medium and high rise residential dwellings, a golf course and associated building.

These receptors are exposed to varying degrees of traffic (ambient) noise on Yonge

Street as a result of factors such as distance setbacks (as close as 50m), elevation of the receptor above ground level or above/below Yonge Street and ground cover within the intervening distance setbacks. Perhaps the lowest ambient sound levels are those at the golf greens (below Yonge Street) and at the single family dwellings along Mill

Street.

2

Based on approximate structure Transmission Loss of 25 dBA

169

Impact assessment and the degree of noise impact, and hence the extent of noise mitigation, depend on how high the subway sound levels are relative to the MOE/TTC

Protocol objective of Leq 55 dBA and the significance of the sound level change above the existing ambient due to traffic.

Table F below includes a summary of the predicted ambient and subway sound levels at the closest points of reception.

TABLE F

PREDICTED AMBIENT AND SUBWAY SOUND LEVELS

Receptor Existing Steel Viaduct Totally Enclosed Movement on Flat Open Concrete

Ambient

Leq day Leq dBA day

Change dBA

Viaduct

Leq dBA day

Change dBA

Ground

Leq dBA day

Change dBA

Viaduct

Leq dBA day

Change dBA

Closest residential receptor @

60m

Closest Golf

Course

Green @

27m

60 75 +15 50 Nil 62 +2 72 +12

55 78 +23 53 Nil 65 +10 75 +20

These levels are higher than the MOE/TTC Protocol criteria and are expected to be noticeably higher than traffic noise on Yonge Street especially for the golf course as traffic noise on Yonge Street will be lower due to its lower grade elevations. At night, public perception is also expected to be significant when vehicular traffic noise is reduced.

Therefore, it is our finding that the viaduct alternative is predicted to result in significant noise impacts for all alternatives except for the totally enclosed concrete alternative.

Potential For Noise Control Measures

At the outset, it is important to state the fact that subway track isolation will not result in any appreciable reduction to the airborne noise from an open viaduct. Accordingly, one should consider the other well known noise control options such as reduction of the size of the openings in the viaduct, the application of sound absorbing materials to the various interior surfaces to suite and the use of concrete structure instead of a steel structure.

It is important to note that the application of noise control measures in the form of suitable sound absorbing surface finish materials to the concrete structure would result in significant acoustic improvements that may result in sound levels that are comparable to or even lower than a subway train moving on flat ground. The material should have fairly high sound absorption co-efficient down to 60 Hz and to be applied to the

170

underside of the ceiling and the inner sides of the viaduct parapet walls. With the application of these materials, the predicted noise levels would be equal to or less than

57dBA at the closest residential receptor and equal to or less than 60 dBA at the closest

Golf Course Green.

Enclosing the subway line in a concrete structure would certainly eliminate the concerns with a predicted outside sound level within the low to mid 50’s dBA which will blend with the outside ambient due to traffic.

Based on the findings of this study, it is recommended that the necessary noise/vibration control measures be considered, the details of which should be evaluated during the detail design stage.

171

T

SUBJECT

SUBWAY

SECTION

FIGURE J: SUBJECT SUBWAY CROSSING AREA OVER YONGE STREET IN THORNHILL

N

172

FIGURE K: PROPOSED EAST DON RIVER SUBWAY LINE CROSSING

173

PROPOSED SUBWAY LINE

VIADUCT UNDER YONGE

STREET NEW BRIDGE

STRUCTURE

FIGURE L: ARTIST RENDERING OF A SUBWAY VIADUCT UNDER A NEW YONGE STREET BRIDGE

174

SUBWAY LINE

VIADUCT BELOW

BLOOR ST BRIDGE

MEASUREMENT

LOCATION

FIGURE M: THE EXISTING SUBWAY VIADUCT ALONG BLOOR STREET

EAST AND THE SOUND MEASUREMENT LOCATION

175

N

1/3 OCTAVE BANDS

100

95

90

85

80

75

70

65

60

55

50

LINEAR/UN-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS

1/3 Octave Bands Centre Frequency, Hz

East Bound @ 30m West Bound @ 45m

Log Average of All Levels

100

95

90

85

80

75

70

65

60

55

50

A-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS


East Bound @ 30m

0.00

0.00

0.00

0.00

Log Average of All Levels

West Bound @ 45m

0.00

0.00

0.00

0.00

FIGURE N.1: SUMMARY OF THE MEASURED Lmax SOUND LEVELS FROM THE BLOOR SUBWAY VIADUCT

176

1/3 OCTAVE BANDS

100

95

90

85

80

75

70

65

60

55

50

LINEAR/UN-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS


Subway Train in Steel Viaduct@ 30m Subway Train on Flat Ground @ 30m

100

95

90

85

80

75

70

65

60

55

50

A-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS


Subway Train in Steel Viaduct@ 30m

0.00

0.00

0.00

0.00

Subway Train on Flat Ground @ 30m

0.00

0.00

0.00

0.00

FIGURE N.2: COMPARISON BETWEEN THE MEASURED Lmax SOUND LEVELS FROM SUBWAY TRAIN

MOVEMENTS IN A STEEL STRUCTURE VIADUCT WITH TRAINS MOVING ON FLAT GROUND

177

PHOTOGRAPHS 1.a TO 1.d: THE BLOOR VIADUCT

178

PHOTOGRAPHS 2.a TO 2.d: NOISE MEASUREMENT ARRANGEMENTS

179

L4B dbA 123

ONT

TRANSFORMER SUBSTATIONS

In the course of assessing the potential noise impact due to the electrical transformer substations for the proposed undertaking, staff of SS Wilson Associates visited three substations serving the existing Yonge Street and Sheppard Avenue subway lines. The substations are located within the Fairview Mall on Don Mills Road north of Sheppard

Avenue East, at the south-east corner of Old York Mills Road and Yonge Street and at

Hendon Avenue west of Yonge Street. These installations are expected to be similar to the future substations for this undertaking.

The noted transformers are all enclosed in masonry structures with open roofs as shown in Figure O. Photograph 3 illustrates a top view of the Fairview Mall substation which serves the Sheppard Avenue East subway line.

From the acoustics viewpoint, the noise from these substations is not audible even in close proximity to the structures when standing on ground level. As one moves up in height in close proximity to the structure, transformer noise becomes barely audible due to the relatively moderate to high ambient noise. Their sound levels can hardly be measured with a sound level meter.

The only possible exception where such transformer noise could be audible, and perhaps exceed the Provincial guidelines, is when such structures are placed in very quiet areas with two or more storey residential dwellings in very close proximity; i.e. overlooking directly the inside of such structures.

In summary, it is our finding, based on knowledge of the subject area being close to

Yonge Street, that electric transformer substations are not likely to be of concern for the proposed undertaking and that the application of noise mitigation measures beyond the outside structures is highly unlikely.

To ascertain the above findings and to comply with the Provincial C of A standards, the

Recommendation Section in this Study contains specific recommendations to address this issue during the process of detail design and submission of the necessary C of A documentation to the MOE.

180

N

Electric

Substatio

Electric

Substatio

Electric

Substatio

FIGURE O: LOCATION OF TYPICAL EXISTING TRANSFORMER SUBSTATIONS

181

PHOTOGRAPH 3: TYPICAL EXISTING TRANSFORMER SUBSTATION

182

Ventilation Shafts

Since most of the subway line will be underground, there should be no air-borne noise impacts from the subway vehicles. The only potential for hearing subway vehicle noise at the surface is from station ventilation fans and ventilation shafts.

Noise from ventilation shafts could be significant where the shafts coincide with special trackwork and where the shafts are situated very close to residential units located in quiet settings away from major roadways.

The proposed subway alignment drawings show the locations of several ventilation shafts which are located in proximity to residential buildings along Yonge Street.

While the ambient noise due to Yonge Street vehicular traffic is the dominant source of noise, the noise due to the subway line may occasionally be audible through the proposed ventilation shafts in particular during traffic lulls.

These shafts can be acoustically treated to lower noise to acceptable levels. The acoustical treatment may involve the use of lined turns and bends, partial barriers/enclosure near the ground surface and the application of special sound absorbing material to the inside walls of the shaft. The issue of noise in this case is considered as a routine technical matter for detailed design purposes.

In addition, ventilation fans may be located at each station and at the emergency service buildings. The fans at the emergency service buildings are used only during train emergencies, so operating noise is not a relevant consideration. The fans at the stations, however, are used on a more regular basis. Noise from the fans at the stations may not be a problem and street level noise criteria can be met by the use of fan silencers and shaft attenuation materials. Locating fans near the tracks rather than near street level can also help if there are turns in the shafts. This is also considered as a routine technical design factor.

183

SS WILSON ASSOCIATES Consulting Engineers

SS WILSON ASSOCIATES

Consulting Engineers

ATTACHMENT 1

GLOSSARY

ATTACHMENT 2

SOUND AND VIBRATION LEVEL CRITERIA

ATTACHMENT 3

ROAD TRAFFIC DATA

ATTACHMENT 4

CALCULATIONS

ATTACHMENT 5

SPECIFIC NOISE ASSESSMENTS

FIGURE C: THE SUBJECT AREA AND THE SELECTED RECEPTOR LOCATIONS

FIGURE D.1: MEASURED EXISTING AMBIENT SOUND LEVELS AT LOCATION

Ld (OCTOBER 29 TO NOVEMBER 3, 2008)

FIGURE D.2: SUMMARY OF MEASURED EXISTING HOURLY AMBIENT SOUND

LEVELS AT LOCATION Ld (HOURLY AND DAILY DATA)

TYPICAL

RECEPTOR

LOCATION

MEASURED EXISTING

DAYTIME SOUND LEVEL:

Leq 59 dBA

EXISTING SOUND ABSORBING

GROUND COVER (VEGETATION)

DIRECT LINE-OF-SIGHT FROM

THE NOISE SOURCE TO A

RECEPTOR INCLUDING GROUND

ATTENUATION

FIGURE E: CONCEPTUAL SECTION THROUGH THE EXISTING

PREDICTED DAYTIME SOUND

LEVEL WITH THE PARKING

LOT: Leq 68 dBA

ADDITIONAL REFLECTED

SOUND AND LOSS OF GROUND

ATTENUATION

FIGURE F: CONCEPTUAL SECTION THROUGH THE PROPOSED PARKING AREA

TYPICAL- TRAFFIC ON

HWY 407

TYPICAL- TRAFFIC ON

HWY 407

PROPOSED SOUND BARRIER

ALONG THE JOINT PROPERTY LINE

2.0m BASE BERM + 4.0m NOISE

WALL ATOP

TYPICAL- TRAFFIC ON HWY

407

FIGURE G: CONCEPTUAL SECTION THROUGH THE PROPOSED PROPERTY LINE SOUND BARRIER

FIGURE H: TYPICAL SOUND BARRIERS

TYPICAL PROPERTY LINE

SOUND BARRIER

ALIGNMENT

FIGURE I: SOUND BARRIER ALIGNMENT

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