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The Regional Municipality of Durham
HAZARD ANALYSISAND
RISK ASSESSMENTFINAL REPORT
Submitted by:
Stevenato & Associates54 Centre Ave., North York, Ontario, M2M 2L5Phone (416) 229-2115Fax: (416) 229-0068
And
J ohn Newton Associates262 Robert St., Toronto, Ontario, M5S 2K8
Phone (416) 929-3621
Email: j.newton@utoronto.ca
J uly, 2002reviewed annually last reviewed November 2008
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TABLE OF CONTENTS
1.0 Introduction......................................................................................................................................1
1.1 Purpose of the Hazard Analysis/Risk Assessment............................................................1
1.2 Overview of the Hazard Analysis/Risk Assessment....................................................2
1.3 Existing Hazards..........................................................................................................2
2.0 Research Design and Implementation.............................................................................................5
2.1 Design of Research Survey.................................................................................................5
2.2 Selection of Recipients........................................................................................................6
2.3 Implementation of Survey...................................................................................................6
2.4 Background Information.....................................................................................................9
3.0 Hazard Data Analysis.....................................................................................................................113.1 Information Provided by Recipients..................................................................................11
3.2 Historical Information on Significant Emergencies.........................................................12
3.3 Potential Natural Hazards..................................................................................................15
3.4 Potential Human-Based Hazards.......................................................................................21
3.5 Potential Technical Hazards..............................................................................................23
3.6 Summary of Hazards by Municipality..............................................................................31
4.0 Risk Assessment.............................................................................................................................35
4.1 Risk Assessment Methodology.........................................................................................35
4.2 Impact Assessment.............................................................................................................36
4.3 Probability Assessment......................................................................................................38
4.4 Calculation of Relative Risk..............................................................................................39
5.0 Hazard Mitigation...........................................................................................................................45
6.0 Conclusions and Recommendations..............................................................................................47
6.1 Evolving Hazards...............................................................................................................47
6.2 Summary and Recommendations......................................................................................48
APPENDICES
A. List of Research Recipients...............................................................................................................51B. Information on GIS............................................................................................................................53
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Section 1 Introduction
Understanding the hazards to which one is exposed and appreciating ones existing capability to
cope with such hazards, represents an initial step towards preparation for such events. The
Regional Municipality of Durhams Emergency Measures Office (DEMO), in recognizing this
need, issued a Request for Proposals, and subsequently retained the team of Stevenato &
Associates and John Newton Associates on September 13, 2001 to prepare a Hazard Analysis
and Risk Assessment for the Region of Durham.
1.1 Purpose of the Hazard Analysis/Risk AssessmentThe preparation of a hazard analysis and risk assessment is an important first step in the
emergency planning process. The results of this research will be of value in helping Regional
staff understand the probability and severity of emergencies that may occur in the Region. With
this knowledge, the level of preparedness can be assessed and measures taken to enhance
capabilities through training and preparation of a more effective response to such occurrences.
Consequently, it is felt that a rigorous hazard analysis and risk assessment process represents a
valuable emergency-planning tool for the Region.
Moreover, the passage of Bill 148 through the Ontario Legislature will amend the current
Emergency Plans Act to require emergency management activities to include the identification
and assessment of the various risks and hazards to public safety that could give rise to
emergencies1. To that end, this document will provide the Region of Durham with an
assessment that will likely address this requirement when the legislation is formally approved
and implemented. This assessment will also provide a foundation for addressing the emergency
management program referred to in the forthcoming legislation.
1 Draft copy of Bill 148, An Act to provide for declarations of death in certain circumstances and to amend theEmergency Plans Act, December 2001, p. i.
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1.2 Overview of the Hazard Analysis/Risk Assessment
The approach required to undertake this project involved background research, the design of
research tools, identification of appropriate recipients in the Region and other agencies, and the
distribution of a self-assessment protocol. Information from background research and the
surveys was combined and then analyzed; resulting in this report. One survey response was
received from each municipality and two (2) from Regional Departments (Health and Works
see Table 1). Therefore, the analysis and risk assessment was based on the municipal responses
and the background research.
1.3 Existing Hazards
The hazards to residents, businesses, the environment and property in Durham Region are
significant and abundant, given that:
(a) Highways 401, 35/115, 48, 7, 7A and 12 transect the Region where there are highvolumes of traffic and accidents involving multiple vehicles and/or trucks carryinghazardous materials.
(b) Major CN and CP railway lines (two of each) transverse the Region carrying highvolumes of a wide range of industrial goods, many of which are hazardous;
(c)Two commodity pipelines transverse the Region (Trans-Canada Gas Pipeline, Trans-Northern Oil Pipeline);
(d)There are major heavy industrial areas predominantly along the lakeshore communitiesthat process, store and transport large volumes of dangerous goods;
(e)There are the two nuclear generating stations (Pickering Nuclear Generating Station andDarlington Nuclear Generating Station) that pose risks such as radiation releases oremergencies resulting from terrorist activities. A nuclear emergency may result in anevacuation, where the outlying communities may have to prepare to receive a largenumber of evacuees from the shoreline municipalities of Ajax, Pickering, Whitby,Oshawa and Clarington;
(f) There are numerous built-up flood prone areas in floodplains of rivers and creeks;(g)There is an international port in Oshawa where there is potential for shipping accidents
and spills;
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(h)There are numerous flight paths of large aircraft to and from Pearson InternationalAirport;
(i) The Oshawa Airport has had numerous small accidents reported by the TransportationSafety Board since 1976.
(j) The Region has an ever-increasing population and high-density areas. In the last fiveyears, Durham Regions population has grown at an annual growth rate of 2.3% (11,600persons per year), from 472,800 in 1996, to an estimated 531,000 in 2001. The Regionhas estimated that the population will grow to 590,000-610,000 by 2006. Populationgrowth rates are expected to increase significantly after 2006, when additional majorgrowth-related infrastructure is anticipated to be in place (e.g., construction of Highway407 to east of Brock Rd., Highway 401 improvements) and population has grown inresponse. The Region has estimated that the population will grow to 790,100 by 2011,874,200 by 2016 and 951,300 by 2021;
(k) Water access to Lake Ontario, Lake Simcoe, Lake Scugog and the Trent-SevernWaterway creates unique water based emergency hazards related to commercial shipping,recreational boating, ice fishing, snowmobiling, and beach use;
(l) The Region attracts a large number of tourists (to festivals, historic sites, waterways) andseasonal visitors who may be unfamiliar with the area during an evacuation;
(m)There are a large number of sensitive facilities found in high-risk locations (i.e., schools,hospitals, recreation facilities, homes for the aged, seniors residences, nursing homes,daycares)
(n) Weather conditions can be extreme (e.g., fog and icy roads along Highway 401, storms,etc.);
(o) Durham Region borders the City of Toronto to the west where there are equivalent, if nothigher risks compared to Durham Region. Emergencies occurring in the City of Torontocould also impact Durham Region, either directly or indirectly (i.e., evacuees travellingthrough the Region); and
(p)The Municipality of Clarington has large forested areas that have potential for largeforest fires.
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Section 2 Research Design & Implementation
Acquisition of the information needed to undertake the hazards analysis and risk assessment
required that a survey instrument be designed, reviewed and tested, before distribution to
selected individuals in key municipal and regional positions. The attention devoted to the
research design stage should not be underestimated, as the content and nature of the research
tools used contributed significantly to the type and quality of the information collected.
2.1 Design of Research Survey
The survey tool was designed to facilitate ease of completion in order to obtain the highest
possible response rate. Wherever possible, questions used a tick box approach and suggested
options and assessment scales were used. Opportunity for open-ended responses was also
provided with some questions, particularly where responses may require additional detail to
explain unique circumstances. The content and structure of the survey was designed for use by
municipalities in the Region as well as Regional Departments. The final survey document
contained five parts .that are:
(A)Administrative Information basic contact data;(B)Historical Emergency Information details on significant recent events ;(C)Potential Hazards perception of concern about potential natural, human-based and
technical hazards and the effectiveness of mitigative measures to address these hazards;
(D)Relevant Material - availability of background material, including emergency contactdirectories and GIS data management capacity; and,
(E) Closing Question an opportunity to add any other comments.The survey was reviewed with and approved by DEMO before being distributed (mailed) to key
representatives of the eight local municipalities and each of Durham Regions Departments.
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2.2 Selection of Recipients
In coordination with Durham Emergency Measures Office (DEMO) staff, a list of survey
recipients was compiled. Recipients at the eight local municipalities included CAOs, Fire
Chiefs, Directors of Public Works and Directors of Planning. Durham Region recipients
included the following Department Heads: Finance, Medical Officer of Health, Emergency
Medical Services, Planning, Social Services, Works, and Police. A list of the research recipients
can be found in Appendix A.
2.3 Implementation of Survey
The survey was mailed to the identified contacts in each municipality and Durham Region
Department on October 3, 2001. Recipients were requested to complete and return the survey
and any related documents within five days of receipt. They were also requested to coordinate
the collection of information within their jurisdiction to limit the duplication of effort and yet
provide a comprehensive response of views and perceptions.
By early December, one survey had been received from each municipality. In each case, it is
understood, though not formally documented, that one person was designated to complete the
survey on behalf of the municipality, so the results represented largely the view of one individual
and not the summation of a diversity of views from each jurisdiction. Nonetheless, the
individuals responding, most often the municipal Fire Chief, were likely the most knowledgeable
about hazards in their area. Of the 40 surveys distributed (for a list of recipients see App. A), 10
were returned (Table 1), for a response rate of 25%. Two surveys were received from Durham
Region Departments (i.e. Works, Health).
Table 1: Municipalities and Regional Departments Responding to SurveyDurham Region Municipalities Durham Region Departments
SurveyReceived
Pickering
Ajax
Whitby
Oshawa
Clarington
Uxbridge
Scugog
Brock
Finance&
Treasur
Health
Emergency
MedicalServices
Planning
SocialServices
Works
Police
Yes Yes Yes Yes Yes Yes Yes Yes No Yes No No No Yes No
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Tables 2 and 4 show the availability and provision of specific documents requested from
municipal and departmental recipients respectively. The null response from many jurisdictions in
the areas probed, does not necessarily mean such documents do not exist, particularly emergency
response and official land use plans, but rather that the person completing the survey may not
have had the capacity or authority to release them. Similarly, the survey respondents may have
chosen not to send documents, such as emergency contact directories, that may be out-of-date.
Table 2: Documents Provided by Municipalities
Documents Provided - Municipalities
Pickering
Ajax
Whitby
Oshawa
Clarington
Uxbridge
Scugog
Brock
Reports on Past Significant Emergencies -- H -- -- -- -- -- --Previous Hazard Analyses/Risk Assessments -- H -- -- -- -- -- --Emergency & Contingency Plans Y H Y Y -- C C CMunicipal Official Plan Y Y Y -- Y -- Y YPartnership Towards Safer Communities -- N -- -- -- -- -- --Emergency Contact Directories Y H Y Y -- C C C
Y =Yes, a copy was sent to the consultantsN =No document existsH =the document exists, but a copy was not provided to the consultantsC =consultant already had a copy
Table 3: Documents Provided by Durham Region Departments
Documents Provided Durham Region Dept.
Finance&
Treasury
Health
Emergency
Medical
Planning
Social
Services
Works
Police
DEMO
Reports on Past Significant Emergencies -- H -- -- -- N -- --Previous Hazard Analyses/Risk Assessments -- -- -- -- N -- --Emergency & Contingency Plans -- Y -- -- -- Y -- --Municipal Official Plan N/A N/A N/A Y N/A N/A N/A N/APartnership Towards Safer Communities
documents
-- N -- -- -- N -- --
Emergency Contact Directories -- -- -- -- -- H -- --
Y =Yes N =No H =exists, but not provided N/A=Not Applicable
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The creation of ever-expanding volumes of information relevant to good emergency planning
has led to the need for better information management tools and methodologies. When the
information is of a physically distributed nature, it is increasingly being captured in electronic
databases and displayed in a more usable form though the use of geographic information systems
(GIS). In addition, the layering capacity of GIS applications provide for different layers of
information to be combined in ways that aid emergency planners to better appreciate and
understand the hazards they must plan for. Juxtaposition of selected emergency information on
events and or hazards can help identify vulnerability and confirm experiential perceptions of risk
in the Region.
Table 4: Additional Information Available/Provided Municipalities
Records of the following Information Municipalities
Pickering
Ajax
Whitby
Oshawa
Clarington
Uxbridge
Scugog
Brock
Traffic accident locations H H H DK H H N NRoutes for hazardous materials/truck traffic N -- N N H N N NRailway accident locations N N H N H H N NCommunity facilities (e.g., schools, hospitals,etc.)
Y H H H H H DK N
Organizations using List 1 toxic material N H N N H N DK NPopulation density Y H H H H N DK NFloodway & flood prone areas H H H H H H N HGas & oil pipeline locations H H H H H N N NAir flight paths N DK N N N N N NHydroelectric transmission corridors H N H H H N N HWater & sewer systems H H H H H N N HFire prone areas N N N H H N N NOther (street centre line, hydrants,orthophotography)
-- Y -- -- -- -- -- --
Y =Yes N =No DK =dont know H =exists, but not provided
Unfortunately, while extensive information on the geographic distribution of hazards in the
Region has been collected by municipalities, regional departments and other relevant provincialand federal organizations and agencies, very little has been placed in GIS tools, as can be seen
from the survey response data presented in Appendix B.
Table 5: Additional Information Available/Provided Durham Region Dept.
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Records of the following Information Durham Region Dept.
Finance&
Treasury
Health
Emergency
Medical
services
Planning
Social
Services
Works
Police
DEMO
Traffic accident locations -- DK -- -- -- H -- --
Routes for hazardous materials/truck traffic -- DK -- -- -- H -- --Railway accident locations -- DK -- -- -- H -- --Community facilities (schools, hospitals, etc.) -- H -- -- -- DK -- --Organizations using List 1 toxic material -- DK -- -- DK -- --Population density -- DK -- Y -- H -- --Floodway & flood prone areas -- DK -- -- -- H -- --Gas & oil pipeline locations -- DK -- -- -- N -- --Air flight paths -- DK -- -- -- N -- --Hydroelectric transmission corridors -- DK -- -- -- N -- --Water & sewer systems -- -- -- -- H -- --Fire prone areas -- DK -- -- -- N -- --
Y =Yes N =No DK =dont know H =exists, but not provided
2.4 Background Information
In addition to the documents and information requested, from local municipal and regional
contacts, other sources of emergency-related statistics and data were explored through key
informant telephone interviews and Internet searching. The documentation noted below was
referred to during this research.
(a) Hazard analyses and risk assessments from other municipalities (e.g., York Region,Johnson County, North Carolina, City of Victoria)
(b)Transportation Safety Board statistics on marine, railway, air and commodity pipelineaccidents
(c) Ministry of Transportation statistics on Provincial highway collisions, traffic volumesand proportion of commercial vehicles
(d) Conservation Authority floodplain mapping(e) Environment Canada climate information (historical and risk levels)(f) CN Rail dangerous goods commodity volumes(g) Durham Region Influenza Pandemic Contingency Plan(h) Durham Region Emergency Response Procedures Chemical/Biological Terrorist
Incident Plan(i) Durham Region Industries List(j)
Municipal and Region information on roads, railways, industrial land uses, populationprojections, water courses/dams, gas and oil pipelines, hydroelectric transmissioncorridors, power generating stations and international ports.
In many cases, information requested was not available at the level of detail requested, or would
not be provided. The hazard analysis and risk assessment was based on information that was
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collected from the sources identified above. The hazard analysis focused on hazards of a scale
that would require the implementation of a municipal or regional emergency plan.
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Section 3 Hazard Data Analysis
Through the survey document, recipients provided basic information on events worthy of note
occurring within their jurisdiction over the past 20-25 years. A simple estimate of the level of
concern felt by the respondent was given for a wide range of potential hazards. These responses
were analysed in a preliminary manner to provide direct local input to the risk assessment.
3.1 Information Provided by Recipients
The core questions in the survey asked recipients to consider the hazards that have in the past, or
might in the future affect their municipality. Each recipient provided information about hazards
in four areas:
i) historical information on significant emergencies;ii) potential or perceived natural hazards;iii) potential or perceived human-based hazards; and,iv) potential or perceived technical hazards.
While respondents were not asked to consider and rank specific aspects of each hazard, they
would nonetheless likely weigh a number of factors in deciding on their level of concern. Someof the possible considerations respondents took into account are listed below in random order.
i) the immediate hazard of emergencies;ii) the level of confidence of municipal responders;iii) the ability to respond;iv) the training and expertise available;v) the equipment and human resources available;vi) mutual aid resources available from neighbouring municipalities;vii) mitigative actions taken; and,viii) future potential for an emergency due to increasing risks (i.e., new highways, heavy
industrial growth).
The survey results are presented and analysed in Sections 3.2 to 3.7. As previously discussed,
one survey from each municipality was received. Insufficient data (two surveys) was received
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from the Region of Durham departments and as a result, the Durham Region survey results have
been excluded from further analysis and assessment2.
The information collected represents the perception of risk by the respondents, based on their
years of experience, and among others, the factors listed above. In making decisions, an
individuals perception combined with their values and beliefs forms the foundation, which
guides their actions. As well, it is important to note that from the perspective of an external
observer there will be a gap between an individuals perception and the full reality of a situation,
however for the individual perception and reality are virtually synonymous. And whether under
day-to-day conditions or during an emergency people will make decisions based on their
perception of the situation, which includes the best information available at the time.
Consequently, in this project the information received from respondents is considered the best
available at this time.
3.2 Historical Information on Significant Emergencies
A summary of the significant emergencies that were reported by municipalities and collected
from research sources (such as the Transportation Safety Board for rail, marine, air and pipeline
accident data) over the past 20-25 years is presented in Tables 6 and 7 respectively.
Train derailments were the most frequently reported emergencies (although 4 of the 7 accidents
were identified through the TSB data and not by survey respondents, introducing a bias),
followed by chemical-related emergencies (4 occurrences) and major flooding (3 occurrences).
Most of the train derailments occurred at the Oshawa marshalling yards, however the most
serious events occurred at level crossings throughout the Region. Five of the 20 (25%)
emergencies reported were the result of natural disasters; the remaining 75% were technical
emergencies. Most of the emergencies reported in recent years have been technical events. The
number of emergencies reported tends to be higher post-1997 vs. pre-1997, however this may be
due to the fact that more recent emergencies are also more easily remembered or the individuals
2 Should the Region wish to compare the perception of risk expressed by municipalities with that felt by RegionalDepartments, additional information would be required from each of the non-responding departments, eitherthrough completion of the survey or participation in a hazards assessment workshop.
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personal experience in the Region may have been limited. The emergencies tended to be
restricted to within the respondents municipality. Duration tended to be less than 72 hours.
The emergencies identified over the last 20-25 years resulted in no deaths and only seven
injuries, all of which occurred in a 1999 train derailment, indicating either a lack of large serious
events or of readily available data on events causing injury or death. Property damage,
environmental damage and economic loss varied, depending on the scale of the emergency. The
natural disasters tended to result in more than $100,000 in property damage, primarily due to the
geographic scope of such events. Environmental damage reported was minimal except for a few
emergencies involving chemicals.
Table 6: Historical Information on significant emergencies over the past 20-25 years inDurham Region (Chronological) Reported by Municipal Survey Respondents
Jurisdictions Impacted: A =Ajax B =Brock C =Clarington O =OshawaP =Pickering S =Scugog U =Uxbridge W =Whitby
Descriptionof
Emergency
(chronological)
Yearit
Occurred
Jurisdiction
Impacted
Durationof
Impact
(Hours)
#ofInjuries
#ofDeaths
Property
Damage
Environmental
Damage
EconomicLoss
Major Fire, Main St., Beaverton 80 B 24-72 0 0 >$100,000 Minor $100,000-$500,000
Ammonia Leak 82 A 4-24 0 0 $500,000Flash Flood 85 P, U >72 0 0 >$100,000 Moderate >$500,000Small Tornado 89 or 90 C $100,000 Minor $100,000 Minor 72 0 0 72 DK 0 $10,000-
$100,000Moderate DK
Flash Flood July 98 P >72 0 0 >$100,000 Moderate DKHazardous Materials leak 98 W 4-24 0 0 72 0 0 $10,000-
$100,000Minor
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Table 7: Historical Information on significant emergencies over the past 20-25 years in Durham Region(Chronological) Identified Through Research
Jurisdictions Impacted: A =Ajax B =Brock C =Clarington O =OshawaP =Pickering S =Scugog U =Uxbridge W =Whitby
Descriptionof
Emergency
(chronological)
Yearit
Occurred
Jurisdiction
Impacted
Duration
of
Impact
(Hours)
#ofInjuries
#ofDeaths
Property
Damage
Environme
ntal
Damage
EconomicL
oss
Severe thunderstorms struck Torontoand Pickering. Flooding; 149 mm in 4hr.
Sept2/80
P 4-24 DK 2 DK DK DK
11 mm of rain fell on Toronto andneighbouring areas, followed by a fastfreeze during evening rush hour, with100s of accidents.
Dec 9/82 4-24 DK 2 DK DK DK
Winter Storm (Toronto & parts of
Durham) (freezing rain, followed by 25-35 cm of snow; snow emergency)
March
4/85
4-24 0 0 DK DK DK
Rainstorm & high winds in Torontoresulted in power blackouts and floodedstreets and basements. The Don R.almost overflowed
Sept.29/86
4-24 0 0 DK DK DK
Severe thunderstorms struck EastToronto and Pickering, resulting inflooding; 149 mm in four hours)
Aug. 27,28/86
P 24-72 0 0 $2million
DK DK
Winter Storm (Toronto & parts ofDurham) (winds to 100 km/h; multipleaccidents, flight & subway cancellations)
87 24-72 0 0 DK DK DK
5-Day heat wave (Toronto & Durham)
(temp. exceeding 350C; 380C on 7th)
July 6-
10/88
>72 0 0 DK DK DK
CN Train Collision (12 cars derailed, nodangerous good)
Aug. 93 O DK 0 0 DK DK DK
Category 1 emergency at PickeringNuclear Generating Station Reactor 2.Spilled heavy water was contained. Norelease, no off site impact.
Dec.10/94
P 4-24 0 0 0 0 DK
CP Train Derailments (6, 8, 6 carsrespectively, no dangerous goods)
Feb. 95,Feb. 99,June 99
O,railyard
DK 0 0 DK DK DK
CN Train Derailment (6 cars, 1 withdangerous goods release methylmethacrylate)
Sept. 97 O DK 0 0 DK DK DK
CN Train Derailment (15 cars, 51platforms, no dangerous goods)
Nov. 97 B DK 0 0 DK DK DK
Train Derailment (5 cars derailed, 3 withLPG dangerous goods)
Feb. 99 O DK 0 0 DK DK DK
Train Collision/Derailment [18 carsderailed, 8 with dangerous goods(Butadiene, LPG), 5 passenger cars,1500 gal. of fuel spilled, fire - extremepotential for devastation]
Nov. 99 C 24-72 7 0 DK Minor DK
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Two large-scale emergencies occurring prior to 1980 were not mentioned. In 1944, a blizzard
dumped 57 cm. of snow on Durham Region over two days, resulting in twenty-one deaths. On
October 15, 16 1954, Hurricane Hazel impacted the entire Region with extreme wind speeds of
90 km/h with gusts to 126 km/h caused property damage and torrential rains with 200 mm
accumulations producing severe flooding of rivers and creeks. Eight-one people died, 20 bridges
were destroyed and there was $1.3 billion in property damage in southern Ontario.
Based on the information provided by survey respondents and background research, the most
serious emergencies in Durham Region between 1980 and 2001 were:
1980: Fire in Beaverton 1983: Train derailment in Uxbridge 1985: Flash flood in Pickering and Uxbridge 1997: Train derailment outside of Beaverton 1999: Train Collision/Derailment in Clarington
3.3 Level of Concern for Potential Natural Hazards
Survey respondents were asked to rank their level of concern for 24 different types of natural
hazards that could impact their municipality. An analysis of the survey results, presented in
order from the natural hazard of most concern to the natural hazard of least concern can be found
in Table 8. The natural hazards that on average ranked 3.0 (concerned) or higher were:
Ice storm; Blizzard; Electrical storm; Tornado; Electrical Storm/Lightning: Fire; and, Lightning: electrical disruption.
The survey results demonstrate that there is particular concern about extreme weather
emergencies that occur very quickly and can have a severe impact. Possible factors influencing
this perception include, but are not limited to:
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i) there is little time to prepare to respond;ii) the potential for injuries, loss of life and damage to property, the environment and the
economy can be extreme; and,iii) long-term impacts can result (i.e., repair costs).
Table 8: Level of Concern about Natural Hazards Affecting Municipalities
MunicipalitiesHazards due to Natural Hazards
Pickering
Ajax
Whitby
Oshawa
Clarington
Uxbridge
Scugog
Brock
Ave.Rank
Ice Storm 3 3 2 3 2 2 2 2 2.4Blizzard 3 3 4 3 2 3 2 3 2.9
Tornado 4 3 3 3 3 2 3 2 2.9Electrical Storm/Lightning: Fire 3 3 3 3 2 5 2 3 3.0
Lightning: Electrical Disruption 4 3 3 4 3 3 2 2 3.0Cold Wave 3 3 4 3 3 3 2 4 3.1High Winds (70+mph) 3 3 3 4 3 2 3 4 3.1
Torrential Rains 2 3 3 5 4 3 4 2 3.3Earthquake (Magnitude 5 or more) 4 3 3 4 3 4 3 4 3.5Flood: Flash 2 4 4 4 3 3 5 3 3.5Heat Wave 4 4 4 3 3 4 3 4 3.6Drought 4 5 4 5 2 4 2 4 3.8Forest Fire / Smoke 5 3 5 5 1 5 3 3 3.8Flood: Predicable/Seasonal 4 4 4 4 3 3 5 4 3.9Fog 4 3 4 5 3 5 4 4 4.0Hurricane/Typhoon 4 5 4 5 4 5 3 2 4.0
Flood: Dam Burst 5 5 4 5 5 3 5 3 4.5Flood: Lake Surges 4 5 4 5 4 5 5 4 4.5Hail 4 4 4 5 5 5 4 5 4.5Frost 5 4 4 5 5 5 4 5 4.6Crop Failure 5 5 4 5 5 4 5 5 4.8Land Subsidence /Liquefaction 5 5 4 5 4 5 5 5 4.8Landslide/Mudslide 5 5 4 5 4 5 5 5 4.8Avalanche: Rock/Debris 5 5 5 5 5 5 5 5 5.0
Average Rank 3.8
Scale: 1: extremely concerned; 2: very concerned; 3: concerned; 4: somewhat concerned;5: not concerned
Clearly, the recent ice storm that hit Eastern Ontario and Qubec in 1998 is still on the minds ofemergency responders as such an event was ranked highly. Concern about blizzards and cold
waves can also be linked to the ice storm experience. Also of concern, particularly with
municipalities that have older (fire-prone) structures, are natural events that can result in major
fires and utility failures (electrical storm and lightning).
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Many of the concerns with weather emergencies are focused on the potential impacts on
Highway 401 and the potential for multiple vehicle accidents, possibly involving dangerous
commodities.
Some regional anomalies appear in the data. For example, Clarington ranked forest fires 1
while other municipalities did not perceive this as a high risk. In Clarington, there is the
Ganaraska Forest as well as the Kendal and Orono Forestry Lands which cause serious concern
for the Clarington Fire Department because the potential for a massive fire is real, and the Fire
Department, which is largely volunteer, is not well trained in forest fire fighting. Two primarily
rural municipalities, Clarington and Scugog, were very concerned about drought, which was not
as highly ranked by other municipalities.
Tornadoes
Municipal respondents ranked tornadoes quite high (2.9). Environment Canada concurs, as
Durham Region has been placed in a moderate risk zone for tornadoes, with an average annual
frequency of 0.8-1.2.
Blizzards
Blizzards, as defined by Environment Canada, are rare in Durham Region, as the required
combination of very cold temperatures, high winds and snow, seldom occur together. There
have been no blizzard warnings for Durham Region in the last ten years. Interestingly,
municipal respondents ranked blizzards high (2.9).
Hurricanes
Hurricanes were ranked low (4.0), and this is also reflected in information provided by
Environment Canada. Hurricanes are very rare in Durham Region, as their energy is greatly
diminished over land. For example, even Hurricane Hazel in October 1954, was actually
downgraded to a tropical storm by the time it reached Ontario.
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Heavy Precipitation
Although blizzards are rare, heavy snowfall is not. Between 1981-2000, there were 18
occurrences of a one-day snowfall greater than 15 cm., equivalent to a 0.2% frequency.
Similarly, between 1981-2000, there were eight occurrences of one-day rainfall greater than 50mm., for a 0.1% frequency rate. Since 1969, the highest daily precipitation recorded was 145
mm. on June 27, 1971, a value greater than a 100-year storm. On three other occasions during
this period, daily precipitation exceeded 70 mm. (1995: 100 mm., 1986: 81 mm., 1984: 71 mm.)
Flooding
Given the history of flooding in parts of Pickering, Uxbridge and Brock, it is surprising that
flooding was ranked quite low. Perhaps past experience has built a strong capability to cope with
floods in these municipalities.
The Conservation Authority Canada-Ontario Flood Damage Reduction Program, Public
Information Flood Risk Maps, illustrates the flood plains for various water systems throughout
Durham Region. The flood plain delineates the area that would be inundated if the river flooded
its banks during a 100-year flood. Structures and property within the flood plain may be
susceptible to damage in the event of flooding. There are three main watersheds in Durham
Region that drain into:
Lake Simcoe (Pefferlaw Brook, Beaverton River, Uxbridge Brook, Whites Creek), Lake Scugog (Nonquon River, Caukers Creek, East Cross Creek), Lake Ontario (Duffin Creek, Carruthers Creek, Lynde Creek, Layton River, Oshawa
Creek, Harmony Creek, Farewell Creek, Black Creek, Bowmanville Creek, Soper creek,Wilmot Creek, Graham Creek and Ganaraska River).
The watersheds for the river systems draining into Lake Simcoe are located in extremely broad,
flat flood plains, resulting in potentially large areas being flooded and an increased likelihood of
flooding compared to the river systems draining into Lake Ontario and Lake Scugog. Much of
these flood plains consist of swamp and marshland. However there are a number of communities
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in the northern part of Durham Region where there are structures on the floodplains, which
would be prone to damage in the event of a flood. They are:
Udora: approximately 100 structures (Pefferlaw Brook) Uxbridge: approximately 40 buildings (Uxbridge Brook) Beaverton: approximately 70 structures (Beaverton River) East of Beaverton: approximately 60 structures (Whites Creek)
There have been very few significant floods in Durham Region. In 1929, a severe storm moved
over the watersheds, washing out area bridges and roads, a portion of the Canadian National
Railway line and a mill dam in Beaverton. Numerous residences and businesses were also
flooded. Extensive flooding occurred on October 15 and 16, 1954 during Hurricane Hazel. The
autumn had been particularly wet, resulting in a saturated ground surface, and when Hurricane
Hazel hit the area, the large amount of rain and resulting floods caused severe damage to roads,
bridges, and dams, as well as public and private buildings. On April 15, 1965, the Brookdale
Dam weakened by heavy rains, breached and flooded downtown Uxbridge. Roads were washed
out and businesses were flooded.3
Climate Data for City of Toronto
Limited climate data was available for Durham Region. However, a report entitled The Climate
of Metropolitan Toronto, by Environment Canada, Atmospheric Environment Service (1989),
provides historical information for Metropolitan Toronto from 1951-1980, and would reflect the
climate of the neighbouring Durham Region. The following summarizes historical information
on climate extremes:
Cold spells (a period of at least three days when minimum temperature falls to 150C orlower) have occurred, on average, slightly more than three times each year. More than75% of the cold spells occur in January.
There is an average of six hot days per year when maximum temperatures reach orexceed 320C.
Heat waves (a period lasting three days or more when maximum temperatures reach atleast 320C) occur, on average, seven times each decade. Heat waves are only slightlymore frequent in July (2.6 days) than June or August. The longest heat wave lasted 10
3 Lake Simcoe Region Conservation Authority, Canada-Ontario Flood Damage Reduction Program, PublicInformation Flood Risk Map, Beaverton River and Whites Creek (1989)
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days during August and early September 1953, and resulted in a few heat fatalities fromheat prostration.
Freezing precipitation is reported an average of 10 times per year. As one approachesLake Ontario, freezing precipitation becomes less frequent due to the influence of therelatively warm Lake in modifying shallow cold air near the surface.
There have been an average of 15 days per year when precipitation amounts exceed 15mm. Normally, the days with heavier precipitation are confined to summer and autumn,however, precipitation occurs more often in winter.
Prolonged wet weather (precipitation lasting at least one week with a minimum of 2 mmof rain per day) only occurs once every couple of years, usually during spring or fall.
A rainfall intensity of 25 mm in a 10-minute period has occurred, on average, once every25 years.
Dry spells (periods lasting at least 15 days without measurable rain) occur, on average,once every two years. The summer of 1988 was the last dry spell.
Wind chill (a measurement of the rate at which heat is lost from an exposed object) inexcess of 1600 W/m2 (equivalent temperature of 380), occurs about 8 times per month inJanuary and six times per month in February. Wind chill is most severe during orfollowing a significant winter storm. A wind chill in excess of 1900 W/m2 is rare.
High wind speeds are usually associated with winter storm passages. The highestaverage wind speed occurred on March 5, 1964 when speeds reached 121 km/h. OnJanuary 26, 1978, average winds of 90 km/h occurred, gusting to 126 km/h, andskyscraper windows popped. In summer, the strongest winds were reported on July 1,1956, reaching 134 km/h.
A humidex of 460
C or higher makes activity difficult. On average, values of 400
C orgreater can be expected on two to three days per summer. On September 1, 1953, thehumidex reached 480C.
Dense fog usually occurs during pre-dawn and dawn hours, usually late winter or earlyspring.
Tornadoes arise from severe thunderstorm outbreaks. From 1970-1979, there was anaverage of 14.5 tornadoes in Ontario, a majority occurring in southwestern Ontario.Weak tornadoes have touched down in the Toronto area, but it has been estimated that theodds of a damaging tornado hitting the Toronto area once every 20 years. Mosttornadoes occur during the afternoon and early evening and during the months from May
through August. Thunderstorms occur most frequently during June, July and August, with an average of
five to six thunderstorm days per month. Severe thunderstorms can cause limited damagedue to large hail, strong wind gusts and flooding. Severe thunderstorms on August 27/281976 produced flooding and property damage. On August 19, 1981, a severethunderstorm produced tennis-ball sized hail.
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On average, hurricanes brush only southern Ontario every few years, usually bringingwinds not strong enough to cause significant damage and heavy rains no greater inintensity than heavy thunderstorm downpours. Hurricane Hazel, on October 15-16, 1954,is the exception. The Humber River Valley area had 80 fatalities and property damage of24 million dollars.
The Toronto area usually experiences one or two snowstorms per winter when snowfallsexceed 15 cm., often accompanied by blowing and drifting snow. On January 26 and 27,1978, a blizzard struck Toronto with 16 cm of snow, winds gusting to 90 km/h, andvisibilities reduced to near zero. The storm closed many roads in the vicinity, resulted inover 400 injuries, and caused one woman to die from exposure. Costs for southernOntario were estimated at over 41 million dollars.
Toronto averages about three days a season with a freezing precipitation storm lastingmore than four hours. On December 27, 1959, 30 cm of freezing rain fell northeast ofToronto. On December 9, 1986, 11 mm of rain fell followed by a fast freeze, andresulting in hundreds of accidents, scores of injuries and two fatalities.
3.4 Level of Concern for Potential Human-Based Hazards
Survey respondents were asked to rank their level of concern for 24 different types of human-based
hazards that could impact their municipality. An analysis of the survey results, presented in order from
the hazard of most concern to the hazard of least concern, can be found in Table 9. The human-based
hazards that on average ranked 3.0 (concerned) or higher were:
Terrorism; and, Arson.
The types of hazards of most concern tended to be related to external factors (i.e., terrorism)
where there is little control. Clearly, the September 11, 2001 bombing of the World Trade
Center in New York has influenced the decisions of survey respondents as Terrorism was the
number one ranked concern and Bomb Explosion was ranked third. Many of the lakeshore
municipalities are particularly concerned about terrorist, bombing or sabotage hazards at the
Pickering and Darlington Nuclear Generating Stations or major industries; that are perceivedlocally to be prime targets for such activity. The City of Pickering ranked all terrorist type
activity very high, partially because it abuts the City of Toronto where terrorist activity is felt
most likely to occur, with uncertain ramifications for Pickering. The Durham Region
Emergency Response Procedure- Chemical/Biological Terrorist (Bioterrorist) Incident Plan
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states, the threat from an actual chemical/biological terrorist incident in Durham Region is
assessed to be low. However, an event cannot be ruled out.
Table 9: Level of Concern about Human-Based Hazards Affecting Municipalities
Hazards due to Human-based Hazards -Municipalities
Pickering
Ajax
Whitby
Oshawa
Clarington
Uxbridge
Scugog
Brock
Ave.Rank
Terrorism 2 3 2 4 2 2 2 3 2.5Arson 2 3 3 4 2 4 2 3 2.9Bomb Explosion 2 3 3 3 4 4 3 3 3.1Medical Emergency 4 3 3 4 3 3 2 3 3.1Bomb Hazard 2 3 3 4 4 4 3 3 3.3International Strife 3 3 5 3 3 4 2 4 3.4Vandalism 3 3 4 5 4 3 2 - 3.4
Air Piracy 2 4 2 4 4 3 4 5 3.5Pandemic: Human 3 4 4 5 3 4 2 3 3.5Human Error: Maintenance 4 3 4 5 3 4 3 3 3.6Human Error: Operation 4 3 4 5 3 4 3 3 3.6Human Error: Programmers 4 3 4 5 3 4 3 4 3.8Human Error: Computer Users 4 3 4 5 3 4 3 4 3.8Loss of Key Staff 2 4 4 4 4 5 3 4 3.8Sabotage: Data and Software 3 4 4 4 3 4 3 5 3.8Epidemic: Animal/Insect 4 4 4 4 4 4 4 3 3.9Media Errors 4 4 4 5 4 5 3 3 4.0Riot/Civil Disorder 4 4 4 5 4 3 3 5 4.0Sabotage: Physical 4 4 5 5 2 4 3 5 4.0
Epidemic: Plant 5 4 4 5 4 3 5 3 4.1Labour Dispute/Strike 4 3 4 4 4 5 4 5 4.1Misuse of Resources 4 4 4 5 4 4 4 4 4.1Hostage Taking 5 4 4 5 4 4 5 3 4.3Fraud/Embezzlement 5 5 4 5 5 4 5 3 4.5Other (please specify) bio-terrorism 2Average Rank 3.7
Scale: 1: extremely concerned; 2: very concerned; 3: concerned; 4: somewhat concerned;5: not concerned
In addition to the terrorist-type human-based emergencies, pandemic was ranked high.
Influenza pandemic, for example, can cause sudden, pervasive illness in all age groups, and can
result in a large number of death, extensive workplace absenteeism and a severe strain on
medical services. Some experts predict that we are due for the next influenza pandemic, and
municipalities across the country have prepared pandemic contingency plans to prepare for such
as event. Using a Centre for Disease Control software program, Table 10 estimates the impact,
based on a Durham Region population of 520,099 in 2001.
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Table 10: Estimates of Impact of Influenza Pandemic on Durham Region
Totals % of PopulationPeople Infected 390,074 75%
Clinically Ill 78,015 - 197,638 15% - 38%Require Outpatient Care 35,367 - 88,417 6.8% - 17%Hospitalization Required 572 - 1,560 0.1% - 0.3%Deaths 156 - 572 0.04% - 0.1%
The human-based hazards of most concern are those related to the nuclear generating stations,
major transportation routes (Highway 401 and main railway lines), major industrial areas using
dangerous goods, and utilities.
3.5 Level of Concern for Potential Technical Hazards
Survey respondents were asked to rank their level of concern for 24 different types of technical hazards
that could impact their municipality. An analysis of the survey results, presented in order from the
hazard of most concern to the hazard of least concern, can be found in Table 11. The technical hazards
that on average ranked 3.0 (concerned) or higher were:
Major building fires; Toxic spills enroute; Derailment; Toxic gas release offsite; Toxic gas release onsite; Accidental explosion; Toxic spills onsite; and, Gas/oil pipeline failure.
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Table 11: Level of Concern about Technical Hazards Affecting Municipalities
Hazards due to Technical Hazards Municipalities
Pickering
Ajax
Whitby
Oshawa
Clarington
Uxbridge
Scugog
Brock
Ave.
Rank
Fire: Building(s) - Major 3 2 2 3 2 3 2 3 2.5Toxic Spill (enroute) 4 2 3 3 2 1 3 3 2.6Derailment 3 2 3 3 2 1 5 3 2.8
Toxic Gas Release (off site) 4 2 3 3 3 1 3 3 2.8Toxic Gas Release (on site) 4 2 3 3 3 1 3 3 2.8Accidental Explosion 3 2 3 4 2 3 3 3 2.9
Toxic Spills (on site) 4 2 3 3 2 1 4 4 2.9Gas/oil pipeline failure 3 2 3 4 2 4 3 3 3.0Power Outage: Long Term 4 3 3 4 3 2 3 3 3.1Radiological Accident In Transit 3 2 3 4 2 4 4 3 3.1
Telecommunications Failure Local 4 2 3 4 3 4 2 3 3.1
Telecommunications Failure Regional 4 2 3 4 3 4 2 3 3.1Water: Contamination 3 2 3 4 3 3 3 4 3.1Aircraft Crash 3 3 3 3 2 5 3 4 3.3Water: Supply Limitation/Failure 3 3 3 5 3 3 3 3 3.3Central Computer Equipment Failure 3 3 4 4 3 5 3 4 3.4Radiological Accident On-Site 3 2 3 4 2 5 5 4 3.5Road Closure 3 2 4 5 3 5 3 3 3.5Structural Failure of Building 5 2 3 4 3 4 3 4 3.5Crop Failure 5 4 4 5 4 5 5 4 4.5Upstream Dam/Reservoir Failure 5 5 4 5 4 4 5 5 4.6Ice Jams in Shipping Lanes 5 5 4 5 5 5 5 5 4.9Ship Accident 5 5 5 4 5 5 5 5 4.9Mine Failure 5 5 5 5 5 5 5 5 5.0Average Rank 3.4
Scale: 1: extremely concerned; 2: very concerned; 3: concerned; 4: somewhat concerned;5: not concerned
Clearly, fires and toxic releases [liquid and gas, in transit (rail and road) or onsite] are the main
areas of concern among municipalities. Fires are of particular concern in many of the older,
high-density neighbourhoods where structures are not as fire resistant as todays buildings and
fires not suppressed immediately can spread very quickly and easily.
Municipalities in Durham Region are understandably concerned about toxic releases resulting
from accidents given:
i) the major transportation routes traversing the Region (i.e., Highways 401 and 35/115, CNand CP rail lines and the proposed extension for Highway 407);
ii) the transportation of hazardous materials on these routes; and,
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iii) the large concentrations of heavy industry along the Lake Ontario shoreline using andtransporting toxic materials.
As well, the Darlington and Pickering nuclear generating stations pose potential hazards through
an on-site or in transit radioactive release into the air or water that are highly unlikely to occurbut potentially devastating. The Royal Society of Canada and Canadian Academy of Engineering
report to the Ministry of the Environment and Energy (1996) states We recommend that
detailed emergency planning should be done for accidents resulting from a credible series of
events which could occur with a probability of approximately 10 to the minus 7/reactor year
(once in ten million years per reactor). The somewhat lower ranking of these events may be
indicative of a confidence in current preparedness activities by the facility owners and/or their
municipalities.
The hazard of a telecommunications failure is a concern of municipalities partly because it
severely hampers the ability of a municipality to function on a daily basis or to communicate in a
major emergency. Such failures also can have severe impacts on local and regional economic
activity, creating additional burden on citizens and municipal finances.
Compared to natural and human-based hazards, municipalities are more concerned generally
about technical hazards, as suggested by the average ranking of all hazards in each of the three
classifications (3.4 for technical hazards, 3.7 for human-based hazards and 3.8 for natural
hazards). The municipalities of Ajax, Clarington and Uxbridge were particularly concerned
about technical hazards.
Each of the main modes of transport and storage of toxic materials are described below.
Highway
Table 12 provides a summary of Ministry of Transportation motor vehicle data for Provincial
highways in Durham Region. As the chart indicates, there are about 1,300 collisions, 300
injuries and 10 deaths on Provincial highways in Durham Region per year. There was no
information available regarding how many of these collisions involved commercial vehicles
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and/or hazardous materials. As well, there is an average of about 160,000 vehicles travelling on
Durham Region Provincial highways per day, of which 67% are travelling on Highway 401.
Close to 25,000 of these are commercial vehicles, a significant proportion (a % was not
available) of which are expected to be carrying hazardous materials that could result in an
emergency situation if one was to be involved in a collision. These figures do not take into
consideration factors such as season (summer volume is higher than winter volume, weekday
volume is higher than weekend volume) and location on the highways (i.e., as one travels
towards Toronto on Highway 401, the volume of vehicles increases). Interestingly, the
proportion of commercial vehicles in the vicinity of the Newtonville Rd.-401 and Mill St.-401
intersections on Highway 401 in Clarington is significantly higher (33.5%) than other portions of
the Highway (average 16%), although with volumes increasing towards Toronto, and actual
number of commercial vehicles may not necessarily be higher than other sections of Highway
401. Highway 401 dissects heavily populated areas, and an accident involving dangerous goods
would likely require an evacuation of a large number of people from the emergency area.
Table 12a: Traffic Volume Information System (TVIS) History, Average 1995-1999,Ministry of Transportation Durham Region
Average 1995-1999Highway Length
(Km)
Ave. #
Fatalities
Ave. #
Injuries
Ave. #
Collisions
%
Collisions
Ave.
AnnualDaily
TrafficVolume
#
CommercialVehicles
%
CommercialVehicles
7 67 2.2 38.4 129.2 1.69 7,6567A 23 1.0 23.0 91.4 1.06 8,63012 25 1.8 12.6 52.0 0.59 8,771
35/115 23 0.2 15.0 68.4 0.33 20,59448 8 0.2 5.0 16.2 0.36 4,510
401 59 4.4 208.8 935.2 0.92 101,712TOTAL 205 9.8 302.8 1,292.4 151,873
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Table 12b: Traffic Volume Information System (TVIS) History, 1999Ministry of Transportation Durham Region
1999Highway Length
(Km)#Fatalities
#Injuries #Collisions
%Collisions
Ave.Annual
DailyTrafficVolume
#Commercial
Vehicles
%Commercial
Vehicles
7 67 3 49 131 1.66 7,910 854 10.87A 23 1 23 94 1.06 8,842 681 7.712 25 1 13 60 0.65 9,237 1,219 13.2
35/115 23 0 11 58 0.27 21,614 2,723 12.648 8 0 5 17 0.36 4,675 806 17.3
401 59 5 201 952 0.89 106,800 17,195 16.1TOTAL 205 10 302 1,312 159,078 23,479
Rail
There are four railway lines transversing Durham Region; two Canadian National lines and two
Canadian Pacific lines. They are:
CN Kingston, running parallel to Lake Ontario CP Belleville, running parallel to Lake Ontario CP Havelock, running east-west, north of Regional Road 5 CN Bala, running northeast through Uxbridge
Most railway accidents in Durham Region occur in the GM Oshawa marshalling yard and are
minor due to the slow movement of tank cars. In Canada, 45% of railway accidents occur in
marshalling yards (1996-2000 average). More serious accidents usually involve a main-track
train derailment (14% in Canada, 1996-2000 average), or an accident at a crossing (25% in
Canada, 1996-2000 average), where there is more likely to be a multiple-car derailment (see
Table 14). The proportion of crossing accidents is generally higher during winter months. The
most significant railway accidents in Durham Region are reported in Section 3.2: Historical
Information on Significant Emergencies.
Table 13 provides a summary of Transportation Safety Board of Canada Railway Occurrence
and Casualty Statistics for Canada 1996-2000. Percentages have been provided to indicate the
types of accidents involving dangerous goods that are more likely to occur in Durham Region.
As the table indicates, only 12% of accidents involving dangerous goods in Canada are the result
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of main-track train derailments; more than three-quarters (77%) occur as a result of non-main-
track train collisions or derailments (i.e., in marshalling yards).
Table 13: Transportation Safety Board, Railway Occurrence and Casualty Statistics for Canada 1996-2000
1996-2000 AverageNumber per Year
1996-2000 %
Accidents Involving Dangerous GoodsMain-track Train Derailments 26 12Crossings 6 3Non-Main-Track Train Collisions 44 21Non-Main-Track Train Derailments 118 56All Others 15 7
TOTAL 209 100
Accidents with a Dangerous Goods Release 6Accidents Involving Passenger Trains 53
Table 14: Transportation Safety Board, Number of Cars Involved in Train Derailments,Canada 1996-2000
Number of Cars
1 2 3 4 5-10 10+% of Cars Derailed per Accident Main-Track (Canada 1996-2000 annual average)
39% 10% 5% 4% 22% 20%
% of Cars Derailed per Accident Non-Main-Track TrainCollisions (Canada 1996-2000 annual average)
49% 24% 9% 6% 2% 6%
% of Cars Derailed per Accident Non-Main-Track TrainDerailment (Canada 1996-2000 annual average)
34% 16% 34% 6% 11% 0
There is a large volume and wide range of dangerous goods being transported by rail throughDurham Region. Table 15 provides a list of commodities in which more than 1,000 tanker cars
were transported in Durham Region in 2001 along CN rail lines (no data was available from CP
Rail). The CN and CP east-west railway lines transport a significantly larger volume of
dangerous goods compared to the railway lines running north-south. The CN Kingston line
dissect heavily populated areas, and a derailment involving dangerous goods would likely
require an evacuation of a large number of people from the emergency area.
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Table 15: Number and Type of Dangerous Goods Tanks on CN Rail (more than 1,000 tanks)
Dangerous Tanks on CN Kingston Dangerous Tanks on CN Bala
No. Cars Commodity No. Cars Commodity20,103 Gas Propane 29,545 Sulphuric Acid10,997 Sulphuric Acid 11,423 Al Frt Rte Shpm10,794 Al Frt Rte Shpm 5,280 Vinyl Chloride
8,066 Petro Gas Liquid 3,160 Freight Forward7,753 Butane Gas Liquid 2,741 Gasoline, Nec6,389 Chlorine Gas 2,660 Fuel Oil Distl5,839 Ammonia Anhydrous 2,101 Ammonia Anhydrous5,052 Propylene 1,924 Gas Propane4,404 Caustic Soda, Liquid 1,583 Methanol Methyl3,989 Cyclohexane 1,108 Sulphur Dioxide3,501 Methanol Methyl3,392 Sulphuric Acid3,251 Sodium Chlorate2,394 Hydrogen Peroxide2,388 Fuel Oil Distl2,233 Muriatic Acid1,812 Gasoline, Nec
1,789 Asbestos Articles1,694 Styrene, Liquid1,686 Adiponitrile1,653 Chemicals, Nec1,513 Butane Gas Liquid1,499 Gas Isobutane1,490 Hydrocarbon Gas1,237 Jet Fuels1,049 Hydrogen Peroxide
Aircraft
The Transportation Safety Board of Canada has reported no large aircraft accidents in Durham
Region since 1976. The only large aircraft accidents have occurred at Pearson International
Airport in Brampton, Ontario, west of Durham Region. There is, however, potential for a large
aircraft crash in Durham Region as a number of flight paths are situated over the Region in
which aircraft are either descending to or ascending from Pearson. NavCanada would not
identify the location of these flight paths, or the number of planes using them, for security
reasons. The likelihood of a large aircraft accident in Durham Region is very low.
Oshawa Airport, a regional facility accommodating small aircraft, is located in Durham Region
on Stevenson Rd. in Oshawa. The Transportation Safety Board of Canada has reported a
significant number of minor accidents since 1976. A great majority of these accidents occurred
during landing procedures and in most cases the problem arose from malfunctioning landing
gear, resulting in a plane crash. Because Oshawa Airport is a training facility, many of the
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accidents involved flying students. There were serious injuries in only two cases since 1976.
The most significant incidents are reported in Section 3.2: historical information on emergencies.
Marine
The Transportation Safety Board reports no significant marine accidents involving commercial
vessels since 1975. Most of the incidents reported occurred in Oshawa and Whitby Harbours
during docking and manoeuvring of vessels. There have been other incidents involving fires,
grounding with vessel damage, and minor vessel collisions.
Industrial on site
Durham Region is home to large industrialized areas in the Lake Ontario communities of
Pickering, Ajax, Whitby, Oshawa and to a lesser extent, Clarington. Heavy industry is located
primarily along the Highway 401 / CN Kingston railway line corridor. Table 16 provides the
number of industries per municipality (10 or more industries), in Durham Region (2001).
Table 16: Number of Industries in Durham Region, 2001
Municipality Number of IndustriesAjax 143Whitby 140Oshawa 136Pickering 127Bowmanville 29Uxbridge 28Port Perry 25Courtice 11
TOTAL 639
Although this table does not identify the size of the industries, or whether they use hazardous
materials (this information was not available), it does indicate the shear volume of industries in
Durham Region. The volume of commercial vehicle and rail traffic through the Region suggests
that significant amounts of dangerous goods are transported to and from these industries, and are
being processed and stored on site. There are some very large industries in Durham Region,
including Dupont, PPG and General Motors. There are only a few sites classified as MIACC
Level 1 or 2.
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Commodity Pipeline
There are two commodity pipelines running through Durham Region. The Trans-Northern Oil
Pipeline runs east-west through Durham Region, north of Taunton Rd. until it reaches
Clarington, where it runs on a southeast diagonal. The Trans-Canada Gas Pipeline also runs
east-west through the Region, between the proposed route for Highway 407 and Regional Road
5, again until it reaches Clarington, where it also runs on a southeast diagonal, parallel to the
Trans-Northern Oil Pipeline.
High-pressure transmission lines (the main lines) are a concern because of the potential for
explosion if there is a rupture. Low pressure transmission lines, such as natural gas lines to
residential areas, create less concern as the damaged area can be isolated (shut-off up-line), the
gas can be burned off in a controlled burn and repairs can be made.
3.6 Summary of Hazards by Municipality
Table 17 provides a summary of the hazards identified by municipalities for which there is
concern. Only the types of hazards that were ranked, on average, by municipal respondents, as 1
(extremely concerned), 2 (very concerned) or 3 (concerned) are included in Table 17. The types
of hazards that received an average ranking of 4 (somewhat concerned) or 5 (not concerned)have been eliminated and will not be considered in the risk assessment analysis because of the
lack of perceived risk of these hazards. Many of the hazards that have been eliminated were
ranked low because:
the chance of them occurring may be very low (i.e., dam failure because there are veryfew dams, mine failure because there are no mines, avalanche because there are nomountains),
if they did occur the impact would be minimal, or the municipality may feel confident in its ability to respond to the hazard (i.e., fog, hail,
frost, hostage taking, labour dispute/strike).
In addition to hazards that were ranked low, a number of additional hazards that were ranked
from 1-3 were removed from this summary list that were deemed to be a cause of a hazard,
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rather than the hazard itself or they were not the type of threat that would activate the Regional
Emergency Plan. (For example, arson is a cause, whereas the hazard actually is fire, which is
captured under Fire- major). These causes of hazards threats have been removed from the
risk assessment analysis. They include:
Natural Hazards Human-Based Hazards Technical HazardsElectrical storm/lightning: fire Air piracy Central computer equipment failureLightning: electrical disruption Arson
Torrential rains Bomb hazardInternational strifeMedical emergencySabotage: data and softwareVandalism
In Table 17, the hazards of most concern to municipal respondents (i.e. Level 1 and 2) have beenhighlighted using coloured cells. Hazards for which there is extreme concern are in red, and
hazards for which respondents are very concerned are in yellow.
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Table 17: Summary of Hazards by Municipality
MunicipalitiesHazards
Pickering
Ajax
W
hitby
O
shawa
Clarington
Uxbridge
S
cugog
Brock
Av
e.Rank
Natural HazardsIce Storm 3 3 2 3 2 2 2 2 2.4Blizzard 3 3 4 3 2 3 2 3 2.9Tornado 4 3 3 3 3 2 3 2 2.9Cold Wave 3 3 4 3 3 3 2 4 3.1High Winds (70+mph) 3 3 3 4 3 2 3 4 3.1Earthquake (Magnitude 5 or more) 4 3 3 4 3 4 3 4 3.5Flood: Flash 2 4 4 4 3 3 5 3 3.5Heat Wave 4 4 4 3 3 4 3 4 3.6Drought 4 5 4 5 2 4 2 4 3.8Forest Fire / Smoke 5 3 5 5 1 5 3 3 3.8Flood: Predicable/Seasonal 4 4 4 4 3 3 5 4 3.9
Human-based HazardsTerrorism (NBC) 2 3 2 4 2 2 2 3 2.5Bomb Explosion 2 3 3 3 4 4 3 3 3.1Pandemic: Human 3 4 4 5 3 4 2 3 3.5Epidemic: Animal/Insect 4 4 4 4 4 4 4 3 3.9
Technical HazardsFire: Building(s) - Major 3 2 2 3 2 3 2 3 2.5Toxic Spill (enroute) 4 2 3 3 2 1 3 3 2.6Derailment 3 2 3 3 2 1 5 3 2.8Toxic Gas Release (off site) 4 2 3 3 3 1 3 3 2.8Toxic Gas Release (on site) 4 2 3 3 3 1 3 3 2.8Accidental Explosion 3 2 3 4 2 3 3 3 2.9Toxic Spills (on site) 4 2 3 3 2 1 4 4 2.9
Gas/oil pipeline failure 3 2 3 4 2 4 3 3 3.0Power Outage: Long Term 4 3 3 4 3 2 3 3 3.1Radiological Accident In Transit 3 2 3 4 2 4 4 3 3.1Telecommunications Failure Local 4 2 3 4 3 4 2 3 3.1Telecommunications Failure Regional 4 2 3 4 3 4 2 3 3.1Water: Contamination 3 2 3 4 3 3 3 4 3.1Aircraft Crash 3 3 3 3 2 5 3 4 3.3Water: Supply Limitation/Failure 3 3 3 5 3 3 3 3 3.3Radiological Accident On-Site 3 2 3 4 2 5 5 4 3.5Road Closure 3 2 4 5 3 5 3 3 3.5Structural Failure of Building 5 2 3 4 3 4 3 4 3.5
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Section 4 Risk Assessment
Outside of highly controlled experiments or the use of significant data sets, the assessment of
risk is largely a subjective exercise.The diversity of input, and the scope of interpretation of that
input means the resulting risk profiles are relative rather than absolute. This observation is not
meant to infer a reduced value in the resultant risk profile for Durham Region, but rather to
underscore the tendency of society to expect the exactness of scientific results, where such
results are neither possible, not ultimately more helpful than a relative relationship. It is valuable
to appreciate that risk is not an absolute indeterminate value; risk is much more an individual, or
as in this case, a collectiveperceptionof vulnerability under a given set of circumstances.
While most people will recognize some situations, such as bungee jumping, handling explosives
or scuba diving as high-risk activities, those with experience will rank the risk lower.
Consequently, the assessment of risk, to be a meaningful exercise, and more than a personal
feeling, requires a systematic and rigorous process. The process used in this assessment
combines approaches used by other jurisdictions and in the related field of business impact
analysis. And while numerical analysis is used, the objective here is to understand and appreciate
risk in a particular geographic region, not determine precise values.
4.1 Risk Assessment Methodology
Risk assessment, in the context of this research, examines the probability of occurrence of
credible worst case scenarios and determines the potential adverse effects on a community
through consideration of various direct and indirect impacts resulting from the occurrence of a
hazard. In the absence of extensive historical data, probabilities and impacts are subjectiveassessments drawn from interview information, rational observations and experience with
emergency planning in Durham Region and elsewhere. The methodology used employs a risk
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and vulnerability tool4 customized to allow an interaction of factors that balance key influences
and yet permit the hazards of greatest risk to be clearly identified.
For each of the selected hazards considered by the eight local municipalities (see Table 17),
subjective assessments were made about the potential impact of each hazard and on the
probability of occurrence of each hazard. Based on these values, a relative risk number was
calculated for each hazard (see Formula #1) and the hazards ranked accordingly.
Formula #1: Relative Risk =Impact of Hazard (IH) x Probability of Occurrence (PO)
As well, the relationship of impact to probability is explored in a risk matrix to better understand
the groupings of hazards that warrants attention and will be of most interest to DEMO.
4.2 Impact Assessment
The occurrence of a hazard can have vastly different impacts, from those that may go largely
unnoticed to those that make the front page of the morning newspapers across the country. The
magnitude of the impact is dependent on a variety of life and hazard factors and the level of
concern of the jurisdiction or organization involved. The relationship between these
considerations, given the rating schemes used, is presented in Formula #2.
Life Factors (LF) x Hazard Factors (HF)Formula #2: Impact of Hazard (IH) =
Level of Concern (LC)
Life Factors (LF): Life factors address indirect implications of incidents that are often neglected
or given cursory consideration, yet directly affect the immediate quality of life of residents in the
affected area. Areas of impact considered under life factors include environmental, social,
political, and economic implications.
4 The Risk and Vulnerability Assessment Tool (RAVAT-3) developed by John Newton Associates effectivelycombines probability, impact considerations, hazard characteristics, and local capability and capacity to provide arelative ranking of hazards for organizations, agencies, corporations, and political jurisdictions.
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Hazard Factors (HF): Each hazard will have different characteristics that affect its impact.
While some hazards may have unique measurement criteria (e.g., Richter or Mercilli scales for
earthquakes, F rating for tornadoes), three basic parameters are used here to assess the relative
impact of a hazard. The hazard factors considered are speed of onset, forewarning and duration.
Level of Concern (LC): The respondent for each of the eight municipalities in Durham Region
was asked to rank the level of concern they felt about each of the hazards affecting their
municipality. The combined average rankings obtained through the survey were calculated and
presented in Table 17. This value is used as the regional level of concern for each applicable
hazard.
While not specifically probed in the survey, the rank given to the level of concern by each
respondent (see scale below) is felt to incorporate a number of characteristics and feelings that
the responsible parties in a municipality have about each hazard.
Scale:1: extremely concerned;2: very concerned;3: concerned;4: somewhat concerned;
5: not concerned
For example, various capabilities and capacities such as the level of confidence, readiness,
technical skills, and experience in handling emergencies are all felt to be embedded in the level
of concern selected. Where these characteristics are strong, the level of concern will be low (i.e.
a 4 or 5), whereas if some characteristics are felt to be weak, then a high level of concern (i.e. a 1
or 2) will likely be selected. To obtain a more detailed verification of these characteristics, more
in-depth interviews would be required to complement the self-assessment surveys.
Calculation of the Impact of Hazard: Based on various Life and Hazard Factors and the Level
of Concern selected, the impact can be calculated for each hazard using Formula #2. The results
of this calculation are presented in Table 18. As the impact values represent an interim step in
the risk assessment, analysis of these values is not warranted.
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Table 18: Calculation of Impact of Hazard
Applicable Natural Hazards LF HF LC Impact of Hazard
Blizzard 10 3 2.9 10.3Cold Wave 10 2 3.1 6.5Drought 12 2 3.8 6.3
Earthquake (Magnitude 5 or more) 16 3 3.5 13.7Flood: Flash 9 3 3.5 7.7Flood: Predicable/Seasonal 7 1 3.9 1.8Forest Fire / Smoke 9 2 3.8 4.7Heat Wave 10 2 3.6 5.6High Winds (70+mph) 9 2 3.1 5.8Ice Storm 14 2 2.4 11.7
Tornado 11 2 2.9 7.6
Applicable Human-based Hazards LF HF LC Impact of Hazard
Bomb Explosion 12 3 3.1 11.6Epidemic: Animal/Insect 11 2 3.9 5.6Pandemic: Human 9 2 3.5 5.1
Terrorism (NBC) 15 4 2.5 24.0Applicable Technical Hazards LF HF LC Impact of Hazard
Accidental Explosion 6 3 2.9 6.2Aircraft Crash 8 3 3.3 7.3Derailment 10 4 2.8 14.3Fire: Building(s) - Major 8 3 2.5 9.6Gas/oil pipeline failure 10 3 3.0 10.0Power Outage: Long Term 10 3 3.1 9.7Radiological Accident On-Site 9 3 3.5 7.7Radiological Accident In Transit 14 3 3.1 13.5Road Closure 7 2 3.5 4.0Structural Failure of Building 7 3 3.5 6.0
Telecommunications Failure Local 6 3 3.1 5.8Telecommunications Failure Regional 11 3 3.1 10.6Toxic Spills (on site) 7 3 2.9 7.2Toxic Spill (enroute) 11 3 2.6 12.7Toxic Gas Release (off site) 14 3 2.8 15.0Toxic Gas Release (on site) 8 3 2.8 8.6Water: Contamination 13 4 3.1 16.8Water: Supply Limitation/Failure 12 2 3.3 7.3
4.3 Probability Assessment (Probability of Occurrence or PO)
The determination of the probability that a particular event will occur can be extremely complex
and in some disciplines, such as life insurance, is a dedicated area of focus. To explore the
probability of each applicable hazard occurring in the Region of Durham would require complete
long term historical information and detailed investigations beyond the scope of this project.
However, there are other methods available to gain a reasonable estimate of the probability of
events occurring without the use of statistical analysis.
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For this project, we assess the likelihood, on a scale of 1-5 (i.e. 5 is high), that an event will
occur within a reasonable planning time frame of 3-5 years. This criterion is applied to each of
the applicable hazards and the appropriate Probability of Occurrence (PO) Value assigned.
It is recommended that the probability selection be revisited briefly each year to incorporate the
most recent years experience and refine the PO Values accordingly. It is wise to remember that
it will not be the occurrence of a particular hazard that requires a change in the PO Value, but
rather a change in the frequency of a hazard from that anticipated. For hazards where more
complete information is available, better judgements of probability can be made.
4.4 Calculation of Relative Risk
The Relative Risk is calculated using Formula #1 for each applicable hazard and the results
presented in Table 19. As can be seen in Table 19, the combination of impact and probability
tend to provide a more balanced perspective on each hazard than either characteristic does
independently. For example, while terrorism (NBC) ranks highest on the impact scale, the
probability is low relative to other hazards and thus terrorism does not rank as high in relative
risk. It is, nonetheless, one of the most significant Human-based hazards. A good risk assessment
involves a number of independent decisions that, when combined, produces a relative risk valuethat could not be anticipated based on any one of the decisions. In this manner, the results, as
shown in Table 19 are the outcome of a robust processgiving greater validity and confidence to
the findings.
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Table 19: Calculation of Relative Risk
Applicable Natural Hazards Impact ofHazard
(IH)
Probability ofOccurrence
(PO)
Relative Risk
Blizzard 10.3 5 51.5
Cold Wave 6.5 5 32.5Drought 6.3 3 18.9Earthquake (Magnitude 5 or more) 13.7 1 13.7Flood: Flash 7.7 4 30.8Flood: Predicable/Seasonal 1.8 5 9.0Forest Fire / Smoke 4.7 2 9.4Heat Wave 5.6 5 28.0High Winds (70+mph) 5.8 5 29.0Ice Storm 11.7 2 23.4
Tornado 7.6 2 15.2Applicable Human-based Hazards IH PO Relative Risk
Bomb Explosion 11.6 2 23.2
Epidemic: Animal/Insect 5.6 2 11.2Pandemic: Human 5.1 1 5.1
Terrorism (NBC) 24.0 1 24.0Applicable Technical Hazards IH PO Relative Risk
Accidental Explosion 6.2 3 18.6Aircraft Crash 7.3 1 7.3Derailment 14.3 3 42.9Fire: Building(s) - Major 9.6 5 48.0Gas/oil pipeline failure 10.0 1 10.0Power Outage: Long Term 9.7 2 19.4Radiological Accident On-Site 7.7 1 7.7Radiological Accident In Transit 13.5 1 13.5
Road Closure 4.0 5 20.0Structural Failure of Building 6.0 2 12.0
Telecommunications Failure Local 5.8 3 17.4Telecommunications Failure Regional 10.6 2 21.2Toxic Spills (on site) 7.2 5 36.0Toxic Spill (enroute) 12.7 3 38.1Toxic Gas Release (off site) 15.0 2 30.0Toxic Gas Release (on site) 8.6 3 25.8Water: Contamination 16.8 1 16.8Water: Supply Limitation/Failure 7.3 2 14.6
A basic set of statistical values for the findings is presented in Table 20.
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Table 20: Statistical Data for Relative Risk Findings
Hazards Groups High Low Average Median
Natural 51.5 9.0 21.1 23.4Human-based 24.0 5.1 15.9 17.2
Technical 48.0 7.3 22.2 19.0
Overall Values 51.5 5.1 19.7 19.9
The statistical information calculated in Table 20 based on the full data set does not identify any
significant anomalies. The high relative risk values for the natural and technical hazard groups
are very close to one another, whereas the high relative risk value for the human-based hazard
group is significantly lower (by half). The low relative risk values for each of the hazard groups
are in the same general range. With the exception of the Technical Hazard Group, the average
risk values were slightly lower than the median values, indicating a tendency towards inclusionof a few lower than average risk values in those groups. The list of hazards for Durham Region,
ranked by descending relative risk values (see Table 21), confirms this view as the relative risk
values drop off sharply from the highest value in each grouping. Nonetheless, the medians and
average values are acceptably close, indicating that values at either extreme of the scale do not
dominate the findings. In the context of this analysis, this observation on the data set would
indicate that there has not been a strong tendency to consistently assign high or low values
during the assessment. This does not mean that all values assigned have a greater accuracy, but
that there would appear to have been a lack of any identifiable bias in the data.
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