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 MCCORMICK 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: [email protected]
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
5
3.0 ANALYSES AND RESULTS
9
4.0 CONSTRUCTION NOISE AND VIBRATION IMPACTS
23
5.0 SUMMARY AND RECOMMENDATIONS
26
FIGURES
ATTACHMENT 1:
GLOSSARY
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
1.1
INTRODUCTION
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.
2.
3.
4.
Assess the existing or future-do-nothing environment.
Predict the future project noise and vibration levels.
Assess the impact relative to the applicable criteria (see Section 2).
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.
2.
3.
4.
5.
6.
7.
1.3
Subway line ground-borne vibration
Subway line noise generated inside buildings as a result of ground-borne vibration
Steeles and Richmond Hill bus stations noise
Longbridge/Langstaff Hydro corridor car park noise
Subway line viaduct crossing over the East Don River noise
Subway electrical substation noise
Subway stations air ventilation shafts noise
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:
- Cummer/Drewry Station
- Steeles Station
- Clark Station
- Royal Orchard Station
- Langstaff/Longbridge Station
- Richmond Hill Station
Bus Terminal Stations
Two bus terminal stations are proposed as follows:
- Steeles Station
- 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.
5
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
Commercial
Industrial
Sensitive Buildings
Recommended
Vibration Velocity Level
Criteria, Lv*1
70 dB
70 dB
70 dB
75 dB
80 dB
65 dB
Recommended Indoor
Sound Criteria
35 dBA
35 dBA
35 dBA
40 dBA
45 dBA
30 dBA
Note: Lv is in reference to 10-6 in/sec
2.2
STATIONARY SOURCES OF NOISE CRITERIA
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
Low
=>3 TO <5 dBA
Noticeable
=5 To <10 dBA
High
=>10
Very High
8
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)
9
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
NATURE OF
BUSINESS
R1
Residential
Condominium
R2
Office Building
Residential
Apartment Building
(concrete)
Commercial
R3
5809 Yonge
St.
5801 Yonge
St.
Residential
Bldg
R4
R5
R6
6023 Yonge
St.-Medical
Clinic
R7
Residential
Bldg
R8
6093 Yonge
St.-Dental
Clinic
REASON FOR
SENSITIVITY TO
NOISE/VIBRATION
Perception/Annoyance/
Structural Damage
NOTES
Not Investigated
Meeting Rooms/Halls
Investigated
Institutional
Teaching Facility
Investigated
CommercialMedical
Residential
Apartment Building
(concrete)
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
Perception/Annoyance/
Structural Damage
Investigated
Laboratory/Equipment/
Sensitive Machinery
Investigated
Residential
Apartment Building
(concrete)
CommercialMedical
Perception/Annoyance/
Structural Damage
Not Investigated
Laboratory/Equipment/
Sensitive Machinery
Investigated
10
Not Investigated
RECEPTOR
NAME AND
ADDRESS
NATURE OF
BUSINESS
REASON FOR
SENSITIVITY TO
NOISE/VIBRATION
Chapel, Visitation,
Arrangement Rooms
NOTES
R9
6191 Yonge
St-Jerrett
Funeral
Homes
Commercial
R10
6267 Yonge
St-Act II
Commercial
Precision Machinery
Investigated
R11
7 AthabaskaResidential
Home
Residential Houses
and Townhouses
Perception/Annoyance/
Structural Damage
Not Investigated
R12
6351 Yonge
St.-United
Optical
Commercial
Laboratory/Equipment/
Sensitive Machinery
Investigated
R13
6373 Yonge
St.-Denture
Clinic
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
Investigated
R14
Apartment
Bldg.-7411
Yonge Street
Residential
Apartment Building
(concrete)
Perception/Annoyance/
Structural Damage
Not Investigated
R15
Residential
Townhomes
Residential Houses
and Townhouses
Perception/Annoyance/
Structural Damage
.
Not Investigated
R16
7705 Yonge
St.-Denture
Clinic
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
Investigated
R17
Ballet
Academy
Residential
Bldg
Commercial
Annoyance to Noise
Investigated
Residential
Apartment Building
(concrete)
Residential
Apartment Building
(concrete)
Residential
Apartment Building
(concrete)
Residential
Apartment Building
(concrete)
Commercial
Perception/Annoyance/
Structural Damage
Not Investigated
Perception/Annoyance/
Structural Damage
Not Investigated
Perception/Annoyance/
Structural Damage
Not Investigated
Perception/Annoyance/
Structural Damage
Not Investigated
Meeting Rooms/Offices
Investigated
Chapel, Visitation,
Arrangement Rooms
Investigated
R18
R19
Residential
Bldg
R20
Residential
Bldg
R21
Residential
Bldg
R22
8199 Yonge
St.-Office Bldg
R23
8361 Yonge
St.-Catholic
Cemeteries
Commercial
11
Investigated
RECEPTOR
NAME AND
ADDRESS
NATURE OF
BUSINESS
R24
Residential
Condominium
Residential
Apartment Building
(concrete)
Commercial
Motel
R25
REASON FOR
SENSITIVITY TO
NOISE/VIBRATION
Perception/Annoyance/
Structural Damage
NOTES
Not Investigated
Perception/Annoyance/
Structural Damage
Not Investigated
R26
8646 Yonge
St- Vishnu
Temple
Institutional
Chapel, Meditation
Rooms, Teaching
Facility
Investigated
R27
1 Longbridge
Road-Dental
Clinic
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
Investigated
R28
Residental
Home
Residential Houses
and Townhouses
Perception/Annoyance/
Structural Damage
Not Investigated
R29
Residential
Home
Residential Houses
and Townhouses
Perception/Annoyance/
Structural Damage
Langstaff
Elementary
School
8108 Yonge
St.-Private
High School
Institutional
Teaching Facility,
Library
Institutional
Teaching Facility
8100 Yonge
St.-Medical
Clinic
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
Investigated
8088 Yonge
St.-Jerrett
Funeral
Homes
Commercial
Chapel, Visitation,
Arrangement Rooms
Investigated
R34
8038 Yonge
Street
Residential Houses
and Townhouses
Perception/Annoyance/
Structural Damage
R35
8018 Yonge
St.-Thornhill
Baptist Church
Institutional
Chapel, Counselling
Office, Teaching
Facility
Old Yonge St.Heritage
Home
Commercial
R30
R31
R32
R33
R36
Not Investigated
Investigated
Investigated
12
Structural Damage/
Perception/Annoyance
Not Investigated
Investigated
Investigated
RECEPTOR
R37
R38
R39
R40
R41
R42
R43
NAME AND
ADDRESS
NATURE OF
BUSINESS
7862 Yonge
Street
Commercial
7756 Yonge
St-Wellness
Centre
Commercial
Residential
Bldg
Residential
Apartment Building
(concrete)
Commercial
7616 Yonge
St.Commercial
Bldg
7554 St.Thornhill
Elementary
School
7330 Yonge
St.-Medical
Clinic
7368 Yonge
St-Medical
Offices
Institutional
REASON FOR
SENSITIVITY TO
NOISE/VIBRATION
Structural Damage/
Perception/Annoyance
Structural Damage,
Annoyance (Meditation
Room)
NOTES
Investigated
Investigated
Perception/Annoyance/
Structural Damage
Investigated
Perception/Annoyance/
Structural Damage
Investigated
Teaching Facility
Investigated
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
CommercialMedical
Laboratory/Equipment/
Sensitive Machinery
Perception/Annoyance/
Structural Damage
Investigated
Investigated
R44
Residential
Condominium
R45
Yonge St.Medical Clinic
Residential
Apartment Building
(concrete)
CommercialMedical
R46
6210 Yonge
St.-Residential
Bldg
Residential
Apartment Building
(concrete)
Perception/Annoyance/
Structural Damage
Not Investigated
R47
Residential
Bldg
Perception/Annoyance/
Structural Damage
Not Investigated
R48
6150 Yonge
St.-RS Kane
Funeral Home
Residential
Apartment Building
(concrete)
Commercial
Chapel, Visitation,
Arrangement Rooms
Investigated
R49
6000 Yonge
St.-Residential
Bldg
Residential
Apartment Building
(concrete)
Perception/Annoyance/
Structural Damage
Not Investigated
R50
5900 Yonge
St.-Residential
Bldg
Residential
Apartment Building
(concrete)
Perception/Annoyance/
Structural Damage
Not Investigated
13
Laboratory/Equipment/
Sensitive Machinery
Not Investigated
Investigated
RECEPTOR
NAME AND
ADDRESS
R51
Residential
Bldg
R52
5800 Yonge
St.-Toronto
Hydro Bldg
R53
5734 Yonge
St.,Office
Building
NATURE OF
BUSINESS
Residential
Apartment Building
(concrete)
Commercial
Commercial
REASON FOR
SENSITIVITY TO
NOISE/VIBRATION
Perception/Annoyance/
Structural Damage
NOTES
Not Investigated
Perception/Annoyance
Investigated
Meeting Rooms/Offices
Investigated
The results of the noise and vibration investigations are summarized in Table 4 below:
TABLE 4
MEASURED AMBIENT NOISE AND VIBRATION LEVELS
Range of Measured Ambient Levels
Receptor No.
R3
R9
R23
R27
R30
R33
R35
R38
R41
R42
Name
Address
Horizons
Secondary
School
Jerrett Funeral
Homes
Catholic
Cemeteries
Archdiocese of
Toronto
Longbridge
Dental Clinic
Langstaff
Elementary
School
Jerrett Funeral
Homes
Thornhill Baptist
Church
Yonge Wellness
Thornhill Public
School
Quest
Reproductive
Medicine
5809 Yonge St.
Vibration Velocity,
dB (ref. 10-6 in/s)
20-34
Indoor Noise Level,
dBA
44
6191 Yonge St.
59-72
36-37
8361 Yonge St.
38-50
32-42
1 Longbridge Rd.
20-33
55-62
8210 Yonge St.
44-53
32-42
8088 Yonge St.
18-60
39-49
8018 Yonge St.
39-46
42-44
7756 Yonge St.
32-42
38
7554 Yonge St.
21-51
43-52
7330 Yonge St.
32-42
60
14
Range of Measured Ambient Levels
Receptor No.
R43
R48
R52
Name
Address
Thornhill Rehab
Centre
R.S. Kane
Funeral Home
Toronto Hydro
7368 Yonge St.
Vibration Velocity,
dB (ref. 10-6 in/s)
29-41
Indoor Noise Level,
dBA
49
6150 Yonge St.
61-76
32-54
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.
i. Bus Stations
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)
15
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.
16
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:
17
•
•
•
•
•
•
•
•
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
4.1
CONSTRUCTION NOISE AND VIBRATION IMPACTS
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:
•
•
•
•
•
•
•
4.3
Driving shafts
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
IMPACT ASSESSMENT
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
5.1
SUMMARY AND RECOMMENDATIONS
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.
b.
c.
d.
e.
f.
Underground subway vehicle movements ground-borne noise and vibration
Bus stations noise
Commuter car park noise
Subway viaduct crossing noise
Electrical transformer substations noise
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 RECOMMENDATIONS
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:
ƒ
ƒ
ƒ
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:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
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
SUBWAY LINE PROFILE
36
FIGURE 4.3
SUBWAY LINE PROFILE
37
FIGURE 4.4
SUBWAY LINE PROFILE
38
FIGURE 4.5
SUBWAY LINE PROFILE
39
FIGURE 4.6
SUBWAY LINE PROFILE
40
FIGURE 4.7
SUBWAY LINE PROFILE
41
FIGURE 4.8
SUBWAY LINE PROFILE
42
FIGURE 4.9
SUBWAY LINE PROFILE
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.
Leq – 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 developments;
• 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
80
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
49750
2.00
10.00
2.00
2.00
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)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(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
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:44:45
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
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 data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 53868/5985 veh/TimePeriod *
Medium truck volume : 1122/125
veh/TimePeriod *
Heavy truck volume : 1122/125
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
51146
2.00
10.00
2.00
2.00
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 !
71.54 !
71.54
--------------------+---------+---------+--------Total
71.54 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
65.01 !
65.01
--------------------+---------+---------+--------Total
65.01 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.54
(NIGHT): 65.01
139
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:45:01
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: section3.te
Time Period: Day/Night 16/8 hours
Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance
setback (Drewry Avenue to Patricia Avenue)
Road data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 58474/6497 veh/TimePeriod *
Medium truck volume : 1218/135
veh/TimePeriod *
Heavy truck volume : 1218/135
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
55520
2.00
10.00
2.00
2.00
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 !
71.90 !
71.90
--------------------+---------+---------+--------Total
71.90 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
65.36 !
65.36
--------------------+---------+---------+--------Total
65.36 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.90
(NIGHT): 65.36
140
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:45:17
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: section4.te
Time Period: Day/Night 16/8 hours
Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance
setback (Patricia Avenue to Moore Park Avenue)
Road data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 57472/6386 veh/TimePeriod *
Medium truck volume : 1197/133
veh/TimePeriod *
Heavy truck volume : 1197/133
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
54568
2.00
10.00
2.00
2.00
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 !
71.82 !
71.82
--------------------+---------+---------+--------Total
71.82 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
65.29 !
65.29
--------------------+---------+---------+--------Total
65.29 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.82
(NIGHT): 65.29
141
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:45:30
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: section5.te
Time Period: Day/Night 16/8 hours
Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance
setback (Moore Park Avenue to Steeles Avenue West)
Road data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 54612/6068 veh/TimePeriod *
Medium truck volume : 1138/126
veh/TimePeriod *
Heavy truck volume : 1138/126
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
51853
2.00
10.00
2.00
2.00
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 !
71.60 !
71.60
--------------------+---------+---------+--------Total
71.60 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
65.06 !
65.06
--------------------+---------+---------+--------Total
65.06 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.60
(NIGHT): 65.06
142
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:45:44
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: section6.te
Time Period: Day/Night 16/8 hours
Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance
setback (Steeles Avenue West to Highland Park Boulevard)
Road data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 53733/5970 veh/TimePeriod *
Medium truck volume : 1119/124
veh/TimePeriod *
Heavy truck volume : 1119/124
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
51018
2.00
10.00
2.00
2.00
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 !
71.53 !
71.53
--------------------+---------+---------+--------Total
71.53 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
64.99 !
64.99
--------------------+---------+---------+--------Total
64.99 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.53
(NIGHT): 64.99
143
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:45:56
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: section7.te
Time Period: Day/Night 16/8 hours
Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance
setback(Highland Park Boulevard to Centre Street)
Road data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 58737/6526 veh/TimePeriod *
Medium truck volume : 1224/136
veh/TimePeriod *
Heavy truck volume : 1224/136
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
55769
2.00
10.00
2.00
2.00
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 !
71.92 !
71.92
--------------------+---------+---------+--------Total
71.92 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
65.38 !
65.38
--------------------+---------+---------+--------Total
65.38 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.92
(NIGHT): 65.38
144
STAMSON 5.0
SUMMARY REPORT
Date: 11-12-2008 13:46:10
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: section8.te
Time Period: Day/Night 16/8 hours
Description: Existing Ambient Sound Levels due to Yonge Street at 15m distance
setback (Centre Street to High Tech Road)
Road data, segment # 1: Yonge Street (day/night)
-----------------------------------------------Car traffic volume : 49794/5533 veh/TimePeriod *
Medium truck volume : 1037/115
veh/TimePeriod *
Heavy truck volume : 1037/115
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):
Percentage of Annual Growth
:
Number of Years of Growth
:
Medium Truck % of Total Volume
:
Heavy Truck % of Total Volume
:
Day (16 hrs) % of Total Volume
:
47278
2.00
10.00
2.00
2.00
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 !
71.20 !
71.20
--------------------+---------+---------+--------Total
71.20 dBA
Result summary (night)
---------------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(m)
! (dBA)
! (dBA)
--------------------+---------+---------+--------1.Yonge Street
!
1.19 !
64.66 !
64.66
--------------------+---------+---------+--------Total
64.66 dBA
TOTAL Leq FROM ALL SOURCES (DAY): 71.20
(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
House on
Highland Park
Boulevard (La)
House on
Steeles Avenue
(Lb)
Predicted
Bus Station
Noise
Leq 1 hr.
Predicted
Ambient
Noise
Leq 1 hr.
Predicted
Excess
Sound Level
Significance
of the Noise
Impact
57 dBA
59 dBA
--
nil
63 dBA
70 dBA
--
nil
148
TABLE B
RICHMOND HILL BUS STATION
Worst Case
Selected
Receptor
Code
Apartment
Building on
High Tech
Road (Lc)
Predicted
Bus Station
Noise
Leq 1 hr.
Predicted
Ambient
Noise
Leq 1 hr.
Predicted
Excess
Sound Level
Significance
of the Noise
Impact
66 dBA
67 dBA
--
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
La
Lb
FIGURE A
STEELES STATION
150
Richmond Hill Station
Lc
FIGURE B
RICHMOND HILL STATION
151
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 4071 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:
Receptor location Le:
Leq16 hr 59 dBA
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
3.5 m high barrier: Leq16 hr 63 dBA
4.0 m high barrier: Leq16 hr 62 dBA
154
-
4.5 m high barrier:
5.0 m high barrier:
5.5 m high barrier:
6.0 m high barrier:
Leq16 hr 61 dBA
Leq16 hr 61 dBA
Leq16 hr 60 dBA
Leq16 hr 59 dBA
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
TABLE C
MEASURED AMBIENT SOUND LEVELS
14 LONGBRIDGE ROAD (Lf)
SSWA RION NL-22 Unit A
Day
1
2
3
4
5
From - To
Period
Period
Leq
00:00:00 AM- 7:00:00 AM
Night
75.0
7:00:00 AM-11:00:00 PM
Day
73.2
11:00:00 PM-00:00:00 AM
Night
57.4
00:00:00 AM- 7:00:00 AM
Night
55.5
7:00:00 AM-11:00:00 PM
Day
61.2
11:00:00 PM-00:00:00 AM
Night
58.8
00:00:00 AM- 7:00:00 AM
Night
56.5
7:00:00 AM-11:00:00 PM
Day
60.4
11:00:00 PM-00:00:00 AM
Night
59.2
00:00:00 AM- 7:00:00 AM
Night
58.0
7:00:00 AM-11:00:00 PM
Day
63.2
11:00:00 PM-00:00:00 AM
Night
59.6
00:00:00 AM- 7:00:00 AM
Night
57.9
7:00:00 AM-11:00:00 PM
Day
73.7
11:00:00 PM-00:00:00 AM
Night
75.0
156
MOE
Descriptor
dBA
Leq day 16 Hrs
73
Leq night 8Hrs
74
Leq day 16 Hrs
61
Leq night 8Hrs
56
Leq day 16 Hrs
60
Leq night 8Hrs
57
Leq day 16 Hrs
63
Leq night 8Hrs
58
Leq day 16 Hrs
74
Leq night 8Hrs
67
TABLE D
MEASURED AMBIENT SOUND LEVELS
28 LONGBRIDGE ROAD (Le)
SSWA RION NL-22 Unit G
Day
1
2
3
4
5
From - To
Period
Period
Leq
00:00:00 AM- 7:00:00 AM
Night
#NUM!
7:00:00 AM-11:00:00 PM
Day
66.2
11:00:00 PM-00:00:00 AM
Night
58.2
00:00:00 AM- 7:00:00 AM
Night
59.7
7:00:00 AM-11:00:00 PM
Day
60.7
11:00:00 PM-00:00:00 AM
Night
58.3
00:00:00 AM- 7:00:00 AM
Night
54.3
7:00:00 AM-11:00:00 PM
Day
62.4
11:00:00 PM-00:00:00 AM
Night
59.8
00:00:00 AM- 7:00:00 AM
Night
56.1
7:00:00 AM-11:00:00 PM
Day
57.2
11:00:00 PM-00:00:00 AM
Night
58.0
00:00:00 AM- 7:00:00 AM
Night
54.8
7:00:00 AM-11:00:00 PM
Day
58.0
11:00:00 PM-00:00:00 AM
Night
#NUM!
157
MOE
Descriptor
dBA
Leq day 16 Hrs
66
Leq night 8Hrs
n/a
Leq day 16 Hrs
61
Leq night 8Hrs
60
Leq day 16 Hrs
62
Leq night 8Hrs
55
Leq day 16 Hrs
57
Leq night 8Hrs
56
Leq day 16 Hrs
58
Leq night 8Hrs
n/a
TABLE E
MEASURED AMBIENT SOUND LEVELS
44 LONGBRIDGE ROAD (Ld)
SSWA RION NL-22 Unit C
Day
1
2
3
4
5
From - To
Period
Period
Leq
00:00:00 AM- 7:00:00 AM
Night
0.0
7:00:00 AM-11:00:00 PM
Day
61.8
11:00:00 PM-00:00:00 AM
Night
54.7
00:00:00 AM- 7:00:00 AM
Night
56.8
7:00:00 AM-11:00:00 PM
Day
59.2
11:00:00 PM-00:00:00 AM
Night
56.7
00:00:00 AM- 7:00:00 AM
Night
55.3
7:00:00 AM-11:00:00 PM
Day
62.4
11:00:00 PM-00:00:00 AM
Night
58.2
00:00:00 AM- 7:00:00 AM
Night
55.1
7:00:00 AM-11:00:00 PM
Day
57.4
11:00:00 PM-00:00:00 AM
Night
56.6
00:00:00 AM- 7:00:00 AM
Night
52.6
7:00:00 AM-11:00:00 PM
Day
58.0
11:00:00 PM-00:00:00 AM
Night
50.8
158
MOE
Descriptor
dBA
Leq day 16 Hrs
62
Leq night 8Hrs
46
Leq day 16 Hrs
59
Leq night 8Hrs
57
Leq day 16 Hrs
62
Leq night 8Hrs
56
Leq day 16 Hrs
57
Leq night 8Hrs
55
Leq day 16 Hrs
58
Leq night 8Hrs
52
N
TYPICAL- NOISE IMPACT
ASSESSMENT LOCATION Lf
(14 LONGBRIDGE ROAD)
TYPICAL- NOISE IMPACT
ASSESSMENT LOCATION Le
(28 LONGBRIDGE ROAD)
TYPICAL- NOISE IMPACT
ASSESSMENT LOCATION Ld
(44 LONGBRIDGE ROAD)
FIGURE C: THE SUBJECT AREA AND THE SELECTED RECEPTOR LOCATIONS
159
TYPICAL- PROPOSED
PARKING LOT AREA
Leq
Lmax
Lmin
L01
Hourly Leq Sound Level, dB
L50
160
SS WILSON ASSOCIATES, PROJECT: ……………………………., LOCATION: …………………………………..15 MINUTE INTERVALS SOUND LEVELS
80
75
70
65
60
55
50
45
40
35
30
TIME @ HOURLY INTERVALS
Leq Day & Night
FIGURE D.2: SUMMARY OF MEASURED EXISTING HOURLY AMBIENT SOUND
LEVELS AT LOCATION Ld (HOURLY AND DAILY DATA)
TIME @ 15 MINUTE INTERVALS
L90
FIGURE D.1: MEASURED EXISTING AMBIENT SOUND LEVELS AT LOCATION
Ld (OCTOBER 29 TO NOVEMBER 3, 2008)
23:30:00
23:00:00
22:30:00
22:00:00
21:30:00
21:00:00
20:30:00
20:00:00
19:30:00
19:00:00
18:30:00
18:00:00
17:30:00
17:00:00
16:30:00
16:00:00
15:30:00
15:00:00
14:30:00
14:00:00
13:30:00
13:00:00
12:30:00
12:00:00
11:30:00
11:00:00
10:30:00
10:00:00
9:30:00
9:00:00
8:30:00
8:00:00
7:30:00
7:00:00
6:30:00
6:00:00
5:30:00
5:00:00
4:30:00
4:00:00
3:30:00
3:00:00
2:30:00
2:00:00
1:30:00
1:00:00
0:30:00
0:00:00
23:30:00
23:00:00
22:30:00
22:00:00
21:30:00
21:00:00
20:30:00
20:00:00
19:30:00
19:00:00
18:30:00
18:00:00
17:30:00
17:00:00
16:30:00
16:00:00
15:30:00
15:00:00
14:30:00
14:00:00
13:30:00
13:00:00
12:30:00
12:00:00
11:30:00
11:00:00
10:30:00
10:00:00
9:30:00
9:00:00
8:30:00
8:00:00
7:30:00
7:00:00
6:30:00
6:00:00
5:30:00
5:00:00
4:30:00
4:00:00
3:30:00
3:00:00
2:30:00
2:00:00
1:30:00
1:00:00
0:30:00
0:00:00
23:30:00
23:00:00
22:30:00
22:00:00
21:30:00
21:00:00
20:30:00
20:00:00
19:30:00
19:00:00
18:30:00
18:00:00
17:30:00
17:00:00
16:30:00
16:00:00
15:30:00
15:00:00
14:30:00
14:00:00
13:30:00
13:00:00
12:30:00
12:00:00
11:30:00
11:00:00
10:30:00
10:00:00
9:30:00
9:00:00
8:30:00
8:00:00
7:30:00
7:00:00
6:30:00
6:00:00
5:30:00
5:00:00
4:30:00
4:00:00
3:30:00
3:00:00
2:30:00
2:00:00
1:30:00
1:00:00
0:30:00
0:00:00
23:30:00
23:00:00
22:30:00
22:00:00
21:30:00
21:00:00
20:30:00
20:00:00
19:30:00
19:00:00
18:30:00
18:00:00
17:30:00
17:00:00
16:30:00
16:00:00
15:30:00
15:00:00
14:30:00
14:00:00
13:30:00
13:00:00
12:30:00
12:00:00
11:30:00
11:00:00
10:30:00
10:00:00
9:30:00
9:00:00
8:30:00
8:00:00
7:30:00
7:00:00
6:30:00
6:00:00
5:30:00
5:00:00
4:30:00
4:00:00
3:30:00
3:00:00
2:30:00
2:00:00
1:30:00
1:00:00
0:30:00
0:00:00
23:30:00
23:00:00
22:30:00
22:00:00
21:30:00
21:00:00
20:30:00
20:00:00
19:30:00
19:00:00
18:30:00
18:00:00
17:30:00
17:00:00
16:30:00
16:00:00
15:30:00
15:00:00
14:30:00
14:00:00
13:30:00
13:00:00
12:30:00
12:00:00
11:30:00
11:00:00
10:30:00
10:00:00
9:30:00
9:00:00
8:30:00
8:00:00
7:30:00
7:00:00
6:30:00
6:00:00
5:30:00
5:00:00
4:30:00
4:00:00
3:30:00
3:00:00
2:30:00
2:00:00
1:30:00
1:00:00
0:30:00
0:00:00
40
SOUND LEVELS, dBA
SOUND LEVELS, dBA
SS WILSON ASSOCIATES, PROJECT: ……………………………., LOCATION: …………………………………..15 MINUTE INTERVALS SOUND LEVELS
80
75
70
65
60
55
50
45
EXISTING SOUND ABSORBING
GROUND COVER (VEGETATION)
TYPICAL
RECEPTOR
LOCATION
MEASURED EXISTING
DAYTIME SOUND LEVEL:
Leq 59 dBA
TYPICAL- TRAFFIC ON
HWY 407
DIRECT LINE-OF-SIGHT FROM
THE NOISE SOURCE TO A
RECEPTOR INCLUDING GROUND
ATTENUATION
TYPICAL- PROPOSED
PARKING LOT AREA
FIGURE E: CONCEPTUAL SECTION THROUGH THE EXISTING AREA
PREDICTED DAYTIME SOUND
LEVEL WITH THE PARKING
LOT: Leq 68 dBA
TYPICAL- TRAFFIC ON
HWY 407
TYPICAL- PROPOSED
PARKING LOT AREA
ADDITIONAL REFLECTED
SOUND AND LOSS OF GROUND
ATTENUATION
FIGURE F: CONCEPTUAL SECTION THROUGH THE PROPOSED PARKING AREA
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
STAMSON 5.0
SUMMARY REPORT
Date: 26-11-2008 14:43:28
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
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 *
Posted speed limit :
100 km/h
Road gradient
:
2 %
Road pavement
:
1 (Typical asphalt or concrete)
Data for Segment # 1: Hwy 407
----------------------------Angle1
Angle2
: -90.00 deg
Wood depth
:
0
No of house rows
:
0
Surface
:
1
Receiver source distance : 280.00 m
Receiver height
:
2.00 m
Topography
:
1
Reference angle
:
0.00
90.00 deg
(No woods.)
(Absorptive ground surface)
(Flat/gentle slope; no barrier)
Result summary
-------------! source !
Road
! Total
! height !
Leq
!
Leq
!
(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
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: hwy40766.te
Time Period: 24 hours
Description: Current Sound levels without Absorptive Ground Surface 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 *
Posted speed limit :
100 km/h
Road gradient
:
2 %
Road pavement
:
1 (Typical asphalt or concrete)
Data for Segment # 1: Hwy 407
----------------------------Angle1
Angle2
: -90.00 deg
Wood depth
:
0
No of house rows
:
0
Surface
:
2
Receiver source distance : 280.00 m
Receiver height
:
2.00 m
Topography
:
1
Reference angle
:
0.00
90.00 deg
(No woods.)
(Reflective ground surface)
(Flat/gentle slope; no barrier)
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
TOTAL Leq FROM ALL SOURCES:
69.73
165
STAMSON 5.0
SUMMARY REPORT
Date: 26-11-2008 14:46:31
MINISTRY OF ENVIRONMENT AND ENERGY / NOISE ASSESSMENT
Filename: hwy407b.te
Time Period: 24 hours
Description: Sound barrier required to keep sound levels at existing
conditions 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 *
Posted speed limit :
100 km/h
Road gradient
:
2 %
Road pavement
:
1 (Typical asphalt or concrete)
Data for Segment # 1: Hwy 407
----------------------------Angle1
Angle2
: -90.00
Wood depth
:
0
No of house rows
:
0
Surface
:
2
Receiver source distance : 280.00
Receiver height
:
2.00
Topography
:
2
barrier)
Barrier angle1
: -90.00
Barrier height
:
6.00
Barrier receiver distance : 22.00
Source elevation
:
0.00
Receiver elevation
:
0.00
Barrier elevation
:
0.00
Reference angle
:
0.00
deg
90.00 deg
(No woods.)
(Reflective ground surface)
m
m
(Flat/gentle slope; with
deg
m
m
m
m
m
Angle2 : 90.00 deg
Road data, segment # 2: Parking Lot
----------------------------------Car traffic volume : 2400 veh/TimePeriod
Medium truck volume :
0 veh/TimePeriod
Heavy truck volume :
0 veh/TimePeriod
Posted speed limit :
40 km/h
Road gradient
:
0 %
Road pavement
:
1 (Typical asphalt or concrete)
Data for Segment # 2: Parking Lot
--------------------------------Angle1
Angle2
: -90.00
Wood depth
:
0
No of house rows
:
0
Surface
:
2
Receiver source distance : 30.00
Receiver height
:
2.00
Topography
:
2
barrier)
Barrier angle1
: -90.00
Barrier height
:
6.00
Barrier receiver distance : 22.00
Source elevation
:
0.00
Receiver elevation
:
0.00
Barrier elevation
:
0.00
Reference angle
:
0.00
deg
90.00 deg
(No woods.)
(Reflective ground surface)
m
m
(Flat/gentle slope; with
deg
m
m
m
m
m
Result summary
--------------
166
Angle2 : 90.00 deg
! source !
Road
! Total
! height !
Leq
!
Leq
!
(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
TOTAL Leq FROM ALL SOURCES:
59.03
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 (Lmax) 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:
ƒ
ƒ
ƒ
ƒ
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.)2
Open concrete viaduct
: Leq day 78 dBA @ 30m
: Leq day 65 dBA @ 30m
: Leq day 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
Closest
residential
receptor @
60m
Closest Golf
Course
Green
@
27m
Existing
Ambient
Leq day
Steel Viaduct
Totally Enclosed
Viaduct
Leq
Change
dBAday
dBA
Movement on Flat
Ground
Leq
Change
dBAday
dBA
Open Concrete
Viaduct
Leq
Change
dBAday
dBA
Leq
dBAday
Change
dBA
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
N
FIGURE J: SUBJECT SUBWAY CROSSING AREA OVER YONGE STREET IN THORNHILL
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
N
FIGURE M: THE EXISTING SUBWAY VIADUCT ALONG BLOOR STREET
EAST AND THE SOUND MEASUREMENT LOCATION
175
1/3 OCTAVE BANDS
A-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS
100
95
95
90
90
85
85
East Bound @ 30m
West Bound @ 45m
Log Average of All Levels
East Bound @ 30m
West Bound @ 45m
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
O.A. dBL
1/3 Octave Bands Centre Frequency, Hz
10 K
6.3 K
4K
2.5K
1.6K
1K
630
400
25
O.A. dBL
1/3 Octave Bands Centre Frequency, Hz
10 K
6.3 K
4K
2.5K
1.6K
1K
50
630
50
400
55
250
55
160
60
100
60
63
65
40
65
250
70
160
70
75
100
75
80
63
80
40
A-Weighted Sound Level, dBA
100
25
Unweighted Sound Level, dB
LINEAR/UN-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS
Log Average of All Levels
FIGURE N.1: SUMMARY OF THE MEASURED Lmax SOUND LEVELS FROM THE BLOOR SUBWAY VIADUCT
176
1/3 OCTAVE BANDS
A-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS
100
95
95
90
90
85
85
Subway Train in Steel [email protected] 30m
1/3 Octave Bands Centre Frequency, Hz
Subway Train on Flat Ground @ 30m
Subway Train in Steel [email protected] 30m
Subway Train on Flat Ground @ 30m
0.00
0.00
0.00
0.00
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
O.A. dBL
10 K
6.3 K
4K
2.5K
1.6K
1K
630
400
25
10 K
6.3 K
O.A. dBL
1/3 Octave Bands Centre Frequency, Hz
4K
2.5K
1.6K
1K
50
630
50
400
55
250
55
160
60
100
60
63
65
40
65
250
70
160
70
75
100
75
80
63
80
40
A-Weighted Sound Level, dBA
100
25
Unweighted Sound Level, dB
LINEAR/UN-WEIGHTED 1/3 OCTAVE BANDS SOUND LEVELS
PHOTOGRAPHS 1.a TO 1.d: THE BLOOR VIADUCT
178
L4B
PHOTOGRAPHS 2.a TO 2.d: NOISE MEASUREMENT ARRANGEMENTS
179
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
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SS WILSON ASSOCIATES Consulting Engineers