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Public Involvement Centre #2 - Air Quality Assessment Results for TPA

Contents:

Model Overview

Dispersion Model:

A mathematical simulation of plume behaviour that predicts how pollutants from stationery and mobile emission sources will disperse into the surrounding environment under given conditions of wind, temperature, turbulence and other environmental factors.

Background Ambient Air Quality Reflects Upwind Emissions

Illustration of emissions sources (airplanes, industry, vehicles) and receptors of interest (vegetation, dwellings, farms)

Dispersion models are typically created by government agencies (like U.S. EPA) and are accepted by other governments like the Ontario Ministry of Environment and Environment Canada.

Required to Set up Model:

  • Background ambient air quality concentrations
  • Hourly meteorology observations
  • Hourly vehicle emission rates
  • Hourly traffic movements and fleet mix
  • Posted vehicle speeds
  • Number of roadway lanes or roadway links
  • Locations of sensitive receptors of Interest (e.g., day cares, schools, senior housing, hospitals)

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Phase 1 - Existing Ambient Environment

Meteorology

Ottawa International Airport (2001): The dominant wind directions in Ottawa are from the Southwest and West-Northwest

Graphic showing wind speeds and from all directions

Contaminants of Interest

Vehicle
Emissions		 Roadway
Emissions
Carbon Monoxide (CO) Yes
Oxides of Nitrogen (NOX) Yes
Volatile Organic Compounds (VOC) Yes
Formaldehyde Yes
Acetaldehyde Yes
Benzene Yes
1,3-Butadiene Yes
Inhalable particulate matter (PM10) Yes Yes
Respirable particulate matter (PM2.5) Yes Yes

Notes:
PM10 - Dust particles less than 10 microns (10-6m) in diameter
PM2.5 - Dust particles less than 2.5 microns (10-6m) in diameter


Relevant Health-based Air Quality Guideline
Contaminant 1—hour AAQC 24—hour AAQC 1—hour NAAQO 24—hour NAAQO
CO (ppm) 36,200 (30) N/A 35,000 (29) 200 (100)
NO2 (ppm) 400 (200) 200 (100) 400 (200) 200 (100)
PM2.5 (µg/m3) N/A 30 1 N/A N/A
PM10 (µg/m3) N/A 50 2 N/A N/A
Formaldehyde (µg/m3) N/A 65 N/A N/A
Acetaldehyde (µg/m3) N/A 500 N/A N/A
Notes: N/A   Not applicable 1   Canada Wide Standard for PM2.5 established for the year 2010 based on the 98th percentile ambient measurement annually, averaged over three consecutive years
AAQC   Ambient Air Quality Criterion
NAAQO   National Ambient Air Quality Objective - Acceptable Levels 2   Interim AAQC


Summary of Historical Ambient Air Quality Measurements
From NAPS Station No. 60104 (Rideau / Wurtemburg)
Supplemented by Measurements from NAPS Station No. 60101 (88 Slater Street)

Pollutant: CO (ppm)
Statistic 1997 1998 1999 2000 2001
One-hour max 9 4 3 3.22 3.0
Annual Mean 0.4 1.1 0.9 0.65 0.64
90th Percentile 1 2 1 0.98 1.0
Times > AAQC of 30 0 0 0 0 0
Pollutant: NO2 (ppb)
Statistic 1997 1998 1999 2000 2001
One-hour max 66 75 93 66 72
Annual Mean 12.5 12.4 12.2 13.8 14.4
90th Percentile 29 28 27 28 27
Times > AAQC of 30 0 0 0 0 0
Pollutant: PM2.5 TEOM (µg/m3)
Statistic 1997 1998 1999 2000 2001
24-hour max 22 42 35 31 32
Annual Mean INS 6.9 6.8 6.3 8.5
90th Percentile 15 16 16 14 18
Times > AAQC of 30 1 0 3 1 1 3
Pollutant: PM10 SSI (µg/m3)
Statistic 1997 1998 1999 2000 2001
24-hour max 47 59 42 41 56
Annual Mean 17 19 17 13 19
90th Percentile 26 35 35 17 22
Times > AAQC of 50 2 0 n/a 0 0 n/a
Pollutant: Benzene (µg/m3)
Statistic 1997 1998 1999 2000 2001
One-hour max. 3.8 4.4 3.32 3.46 2.9
Annual Mean 1.59 1.4 1.23 1.08 0.9
90th Percentile 2.99 2.2 2.01 2.08 1.6
Times > AAQC N/A N/A N/A N/A N/A
Pollutant: Ozone (ppb)
Statistic 1997 1998 1999 2000 2001
24-hour max 90 95 90 69 92
Annual Mean 20.5 19.1 21.2 19.9 25
One-hour max. 39 37 38 35 45
Times > AAQC of 80 5 3 7 0 26
Pollutant: 1,3-Butadiene (µg/m3)
Statistic 1997 1998 1999 2000 2001
One-hour max 0.58 n/a 0.72 0.58 0.5
Annual Mean 0.17 n/a 0.18 0.17 0.2
90th Percentile 0.34 n/a 0.29 0.29 0.3
Times > AAQC N/A N/A N/A N/A N/A
Pollutant: Formaldehyde* (µg/m3)
Statistic 1997 1998 1999 2000 2001
24-hour max 9.2 7.1 6.9 4.6 6.2
Annual Mean 3.3 3.3 3.0 2.6 3.3
90th Percentile 4.5 5.2 4.4 3.8 5.0
Times > AAQC of 65 0 0 0 0 0
Pollutant: Acetaldehyde* (µg/m3)
Statistic 1997 1998 1999 2000 2001
24-hour max 22.8 5.8 4.1 4.0 4.0
Annual Mean 2.3 1.7 1.8 1.6 1.7
90th Percentile 2.7 2.7 2.7 2.3 2.8
Times > AAQC of 500 0 0 0 0 0
Notes: *   Ambient measurements taken from NAPS Station No. 60101 (88 Slater Street), since not available from NAPS Station No. 60104 N/A   Not applicable
n/a   Not available
1   Canada Wide Standard for PM2.5 established for the year 2010 based on the 98th percentile ambient measurement annually, averaged over three consecutive years   NAPS   National Air Pollution Surveillance Network (Environment Canada and Ontario Ministry of Environment)
2   Interim AAQC SSI   Size Selective Inlet Sampler (Non-continuous Monitor)
AAQC   Ambient Air Quality Criterion TEOM   Tapered Element Oscillating Microbalance (Continuous Monitor)
INS   Insufficient data to compute relevant statistics

Measurement Results

Measured concentrations in Ottawa are below ambient guidelines with the exception of ozone and PM2.5 which infrequently exceed the desirable levels (summer time).

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Phase 2 - Vehicle Emission Rates / Traffic Volumes

The U.S. EPA MOBILE 6.2 emission factor model was used. Environment Canada is currently working on a Canadian update to this model (incomplete at the time of the study). Fleet averaged emissions derived from the US and Canadian versions vary by about 10%, which is insignificant.

Vehicle emissions are expected to decrease significantly in the future due to stricter fuel regulations and improved vehicle emission control technologies.

Proposed Reductions in Vehicle Emissions

Regulations and Standards

Regulations governing emissions from vehicles and the composition of gasoline and diesel fuels are important factors for roadway air quality assessments. Regulations are typically developed and adopted in the United States before they are adopted in Canada. The lag time between these events is shrinking and is also becoming less significant because of the high level of integration of the automotive sector across North America.

Tier 1 and Tier 2 Emission Standards

Two sets of standards, Tier 1 and Tier 2, have been defined for light-duty vehicles in the U.S. Clean Air Act Amendments of 1990.

The Tier 1 regulations were fully implemented in 1997 and the Tier 2 are to be phased-in between 2004 and 2009 (see table below).

The Tier 2 regulation brings new requirements for fuel quality, contributing to significant emission reductions relative to the Tier 1 regulation. Cleaner fuels will be required in addition to advanced emission control technology (e.g., catalysts).

Tier 1 and Tier 2 Emission Standards for Light Duty Vehicles
  100,000 Mile (g/VMT)
NMHC NOX
Tier 1 0.31 0.60
Tier 2 0.125 0.20
Notes: Tier 1   Tier 1 light-duty standards apply to all new light duty vehicles, such as passenger cars, light duty trucks, sport utility vehicles (SUV), minivans and pick-up trucks.
Tier 2   The Tier 2 standard applies to all vehicles that were covered by Tier 1 and, additionally, to medium-duty passenger vehicles (e.g., larger SUVs and passenger vans). The same emission limits apply to all engines regardless of the fuel used.
NMHC   Non-Methane Hydrocarbons
g/VMT  Grams per vehicle miles travelled

Control Technologies

There have been considerable advances in emission control technology on conventional vehicles over the past several years. Many of these advances have occurred as a result of the new stricter standards for vehicle exhaust pollutants. Candidate control technologies available to achieve Tier 2 reductions are summarized below.

Tier 1 and Tier 2 Emission Standards for Light Duty Vehicles
  NMHC NOX
Modifications to combustion chamber 3-10% 3-10%
Multiple valves with variable valve timing 30% 3-10%
Increased EGR (including electronic control) 0% ≥ 10%
UEGO 5% 23-35%
Air/fuel control in individual cylinders 22% 3%
Increased EGR (including electronic EGR) 0% ≥ 10%
Air-assisted fuel injectors 3-10% 0%
Catalyst improvements (thermal stability, washcoat, cell densities) 10% 10%
Increased catalyst loading and volume 10% 20%
Advanced catalyst designs (tri-metal, multi-layered) 20-37% 30-57%
Close-coupled catalysts 50-70% 0-10%
Electrically-heated catalysts ≥ 10% 5-10%
HC adsorbers ≥ 10% 0%
Notes: In general, these percentages cannot be simply summed to achieve a total emission reduction when more than one emission control technology is being applied.
HC   Hydrocarbons

MOBILE 6.2 Vehicle Fleet Emissions


Carbon Monoxide (CO) Idle Emission Factor (g/hour): 2001 - 235.9; 2011 - 118.3; 2021 - 88.3

CO Emissions Chart

Volatile Organic Compounds (VOC)
Idle Emission Factor (g/hour): 2001 - 24.7; 2011 - 9.7; 2021 - 5.6

VOC Emissions Chart

Oxides of Nitrogen (NOX)
Idle Emission Factor (g/hour): 2001 - 13.0; 2011 - 6.0; 2021 - 2.6

NOX Emissions Chart

Data in table format

Particulate Emission Factors from Roadway and Exhaust

Roadway Particulate Matter Emission Factors
Roadway Section AWD Traffic Category Silt Loading (g/m2) PM10 (g/VMT) PM2.5 (g/VMT)
Freeway Mainline > 10,000 0.015 0.0916 0
Ramp or Arterial Road > 10,000 0.03 0.2643 0
Ramp 5,000-10,000 0.06 0.5353 0.0225
Notes:   g/ VMT   Grams per vehicle miles traveled
AWD   Average weekday movements


Exhaust Emission Factors
Traffic Movement Year PM10 PM2.5
Free Flow
(g/VMT)		 2001 0.0754 0.0567
2011 0.0405 0.0247
2021 0.0297 0.0148
Idle
(g/hour)		 2001 0.1381 0.1270
2011 0.0962 0.0885
2021 0.0875 0.0805
Notes: MOBILE 6.2 tailpipe particulate matter emission factors are not speed dependent Vehicle particulate matter emission factors include exhaust, brake wear, and tire wear
g/VMT   Grams per vehicle miles traveled


Average Hourly Traffic Volume Distribution

Volume Distribution Chart

Data in table format

Highway 417 Mainline Volume Summary
Highway 417, from Highway 416 Easterly to Anderson Road
Preliminary Design Study and Environmental Assessment

Average Weekday Traffic Volumes (AWD)
Mainline Section
(between interchanges)		 Existing EB Existing WB 2021
No-build EB		 2021
No-build WB		 2021
Build EB		 2021
Build WB
Highway 416 to Richmond Road 48,430 56,040 62,000 70,000 68,000 78,500
Richmond Road to Pinecrest Road / Greenbank Road 59,200 65,300 76,500 85,500 79,000 90,000
Pinecrest Road / Greenbank Road to Woodroffe Avenue * 62,650 69,680 78,000 88,000 82,000 95,000
Woodroffe Avenue * to Maitland Avenue 72,600 74,100 83,500 91,500 87,500 97,500
Maitland Avenue to Carling Avenue 78,040 78,040 89,000 81,500 97,500 95,000
Carling Avenue to Island Park Drive 85,830 77,230 94,500 86,000 96,000 87,500
Island Park Drive to Parkdale Avenue 85,830 80,670 94,500 88,500 96,000 91,000
Parkdale Avenue to Rochester Avenue 88,220 82,910 95,500 89,000 97,000 91,500
Rochester Avenue to Bronson Avenue 81,370 76,770 86,000 82,000 87,500 83,500
Bronson Avenue to Lyon Street 70,850 81,750 78,500 88,000 81,000 82,000
Lyon Street to Kent Street 62,190 73,150 66,500 67,500 69,000 71,000
Kent Street to O'Connor Street 62,190 73,150 73,500 67,500 76,500 71,000
O'Connor Street to Metcalfe Street 61,550 73,400 61,000 66,500 63,500 67,500
Metcalfe Street to Nicholas Street 79,260 79,250 83,500 94,500 87,000 98,500
Nicholas Street to Vanier Parkway 87,350 83,510 86,500 98,000 88,000 101,000
Vanier Parkway to St. Laurent Boulevard 71,580 70,630 76,500 89,500 77,500 91,000
St. Laurent Boulevard to Ottawa 174 IC 61,050 59,550 80,500 85,000 77,000 72,000
Ottawa 174 IC to Innes Road 36,850 37,350 48,500 57,500 50,500 56,000
Innes Road to Walkley Road 29,550 29,100 40,500 38,500 49,000 41,000
Walkley Road to Hunt Club Road 17,200 16,450 29,500 51,500 39,000 56,500
Hunt Club Road to Russell Road 17,200 16,450 27,000 37,500 34,500 37,500
Notes:   EB   Eastbound
WB   Westbound
* Focus: The Woodroffe Avenue interchange was selected for presentation as there are several sensitive receptors in the study area and it included the maximum predicted impact for PM10 in the future build scenario.

Traffic Volume Results

The traffic volume is projected to increase by 2021 relative to 2001. The build volumes are greater than the no-build volumes as additional capacity is generally being added.

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Phase 3 - Dispersion Modelling / Results

The U.S. EPA's CAL3QHCR dispersion model was used.

The freeway was broken into three sections. The modelled sections were represented as a series of links. Sensitive receptors within 250 m of the freeway were considered in the modelling.

Sensitive receptors within the 250m zone are listed below:

10 Daycare facilities
12 Schools
3 Senior housing facilities
1 Hospital

* Focus: The Woodroffe Avenue interchange was selected for presentation as there are several sensitive receptors in the study area and it included the maximum predicted impact for PM10 in the future build scenario.


  *  Example Modelled Section:

Woodroffe Avenue Interchange 
Highway 417 / Pinecrest Road / Greenbank Road / Woodroffe Avenue and sensitive receptors

Arial photo of Woodroffe Ave. Interchange showing emissions dispersion and locations of sensitive receptors

The model simulates the dispersion of emissions from Highway 417 and all on / off ramps and idling vehicles at intersections for each hour of day using changing traffic volumes, variable meteorological conditions, and posted vehicle speeds.

Maximum concentrations over the year are summarized below.



  *  Example Maximum Predicted 24-hour
PM10 Concentrations
For Year 2021 Build Scenario (without background) for Woodroffe Ave. interchange

Arial photo of Woodroffe Ave. Interchange showing maximum emissions concentrations


Maximum Predicted CO and PM10 Results
1-Hour Average CO Concentrations Including Background Concentration (ppm)1
24-Hour Average PM10 Concentrations Including Background Concentration (µg/m3)2
Receptor No. CO: Existing Conditions (2001) CO: Future
No-Build (2021)		 CO: Future Build (2021) Number of Times Above CO 1-Hour Criterion (30 ppm) 3 PM10: Existing Conditions (2001) PM10: Future No-Build (2021) PM10: Future Build (2021) Number of Times Above PM10 24-Hour Criterion (50 µg/m3) 4
R1 3.2 2.3 2.2 0 32.1 31.5 30.7 0
*R2 2.9 2.0 2.2 0 31.4 30.0 29.8 0
*R3 4.5 2.8 3.0 0 38.7 36.0** 36.5** 0
*R4 3.9 2.5 2.7 0 34.9 32.0 32.5 0
*R5 4.1 2.6 2.8 0 35.7 32.5 32.8 0
*R6 4.3 2.7 3.0 0 35.3 32.2 32.5 0
R7 3.0 2.2 2.4 0 31.7 30.4 30.4 0
R8 3.3 2.2 2.5 0 32.1 30.7 31.0 0
R9 2.8 2.0 2.1 0 30.7 29.6 30.0 0
R10 3.3 2.3 2.4 0 32.9 32.2 34.1 0
R11 3.3 2.5 2.2 0 31.9 30.0 30.3 0
R12 7.7** 4.0** 4.2** 0 42.2** 35.5 35.8 0
R13 6.6 3.6 3.9 0 37.7 32.9 33.0 0
R14 3.0 2.0 2.0 0 30.9 30.4 30.8 0
R15 3.4 2.3 2.4 0 30.8 30.0 30.4 0
R16 3.4 1.9 1.9 0 31.0 29.7 30.1 0
R17 2.6 1.8 1.9 0 30.9 29.1 29.2 0
R18 4.1 2.4 2.4 0 33.1 30.7 30.7 0
R19 3.7 2.4 2.4 0 32.6 30.4 30.2 0
R20 3.1 1.8 1.8 0 30.5 29.2 28.9 0
R21 3.2 2.1 2.1 0 33.0 30.4 30.6 0
R22 6.0 3.1 3.2 0 36.5 33.1 33.4 0
R23 6.2 3.3 3.3 0 37.5 34.7 35.1 0
R24 2.5 1.8 1.9 0 30.9 29.7 29.9 0
R25 2.4 1.6 1.7 0 30.7 29.9 30.0 0
R26 2.7 1.8 1.8 0 30.1 29.6 29.2 0
Notes: 1   5-year average (1997-2001) 90th percentile background concentration of CO from NAPS Station No. 60104 equals 1.2 ppm 3   OE's 1-Hour AAQC for CO equals 30 ppm
4   MOE's Interim 24-Hour AAQC for PM10 equals 50 µg/m3
2   5-year average (1997-2001) 90th percentile background concentration of PM10 from NAPS Station No. 60104 equals 27 µg/m3   **   Indicates the highest impact per modelling scenario

Modelling Results

Where the 90th percentile background level is combined with the maximum predicted concentrations, the predicted future levels — build and no-build — are less than the existing levels and all levels are below provincial and federal ambient air quality criteria for all scenarios.

  *  Example Combined Effects Analysis for PM10 — Receptor #3

Chart showing combined effects for R3

Notes:   The predicted annual average increase in 24-hour PM10 levels above ambient levels due to the proposed Highway 417 improvements is 3 µg/m3 or 6% of the MOE's interim guideline

Data in table format

Combined Effects Results

The combined effects analysis evaluates the effect of roadway impacts in addition to background concentrations. Each modelled PM10 concentration is added to the corresponding measured PM10 concentration. Emissions of PM10 for Highway 417 are predicted to result in a small incremental effect in the future-build scenario at Receptor #3. Elevated measured ambient levels of PM10 infrequently exceed the MOE's interim AAQC without Highway 417.

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Phase 4 - Regional Airshed Modelling

Map showing Ottawa Census Division

Smog Contaminants (Ozone and PM2.5)

Smog contaminants form in the atmosphere as secondary pollutants.

The change in Highway 417 emissions for 2001 and 2021 were estimated and compared to emissions for the Ottawa Census Division. The change in smog contaminant levels were estimated using a simple Regional Airshed Model.

Comparison of Highway 417 Emissions to Total Emissions in the Ottawa Census Division


Existing (2001) Emissions (tonnes/year)
Emission Source Sector CO NOX PM10 PM2.5 VOC
Industrial Sources 1,308 3,465 8,357 616 8,043
Non-Industrial Fuel Combustion and Other 13,905 1,994 5,070 2,700 10,141
Transportation:
Roads* 100,220 16,447 754 660 10,603
(Highway 417 mainline emissions**) (15,954) (2,478) (46) (35) (476)
(Highway 417 as percentage of total roads) (16%) (15%) (6%) (5%) (4%)
Off-Roads 85,109 9,271 668 615 7,030
Railroad 101 525 13 12 25
Aircraft 1,098 215 43 30 217
Marine 2,596 368 77 67 816
Totals 189,124 26,826 1,555 1,384 18,690
Open Roadway Sources - Dust from All Roads (paved and unpaved) 0 0 15,651 3,116 0
Total Emissions in the Ottawa Census Division 204,337 32,285 30,633 7,816 36,874
Contribution of the Highway 417 emissions to the total emissions in the census division 8% 8% <1% <1% 1%
Notes:   Emissions for the census division are from the CAC95 EI by Environment Canada. *   Based on MOBILE 5C
**   Based on MOBILE 6.2C


Future (2021) Build Emissions (tonnes/year)
Emission Source Sector CO NOX PM10 PM2.5 VOC
Industrial Sources 1,557 2,259 12,840 825 10,846
Non-Industrial Fuel Combustion and Other 20,133 2,321 7,727 3,820 14,385
Transportation:
Roads* 23,821 1,918 211 120 2,544
(Highway 417 mainline emissions**) (8,520) (507) (23) (11) (146)
(Highway 417 as percentage of total roads) (36%) (26%) (11%) (9%) (6%)
Off-Roads 116,979 10,004 574 529 4,628
Railroad 79 458 11 10 21
Aircraft 1,498 837 81 57 327
Marine 2,930 366 74 65 915
Totals 145,307 13,583 951 781 8,434
Open Roadway Sources - Dust from All Roads (paved and unpaved) 0 0 26,251 5,226 0
Total Emissions in the Ottawa Census Division 166,997 18,163 47,770 10,651 33,665
Contribution of the Highway 417 emissions to the total emissions in the census division 5% 3% <1% <1% <1%
Notes:   Emissions for the census division are from the CAC95 EI by Environment Canada. *   Based on MOBILE 5C
**   Based on MOBILE 6.2C

Regional Airshed Modelling Results

Emissions of CO and NOX from transportation sources in Ottawa are significant contributions to the total emissions in the year 2001. By 2021, emissions from transportation sources are predicted to decrease substantially. Off-road (e.g., lawn mowers, snowmobiles, etc.) combustion emissions are expected to remain a major contributor. The incremental effect from the widening of Highway 417 on ambient levels of PM2.5 and ozone was calculated to be insignificant. Changes less than 0.01% in ambient concentrations were predicted to occur in 2021 in the Ottawa Census Division.

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