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A Unified Ontario Flood Method: Regional Flood Frequency Analysis of Ontario Streams Using Multiple Regression by Kirti Sehgal A thesis submitted in conformity with the requirements for the degree of Master of Applied Science Department of Civil Engineering University of Toronto © Copyright by Kirti Sehgal 2016

A Unified Ontario Flood Method: Regional Flood Frequency ......performed using multiple regression and the equations for the T-year flood quantile (2, 10, 25, 50 and 100 year) were

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Page 1: A Unified Ontario Flood Method: Regional Flood Frequency ......performed using multiple regression and the equations for the T-year flood quantile (2, 10, 25, 50 and 100 year) were

A Unified Ontario Flood Method: Regional Flood Frequency Analysis of Ontario Streams Using Multiple

Regression

by

Kirti Sehgal

A thesis submitted in conformity with the requirements for the degree of Master of Applied Science

Department of Civil Engineering University of Toronto

© Copyright by Kirti Sehgal 2016

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A Unified Ontario Flood Method: Regional Flood Frequency

Analysis of Ontario streams using Multiple Regression

Kirti Sehgal

Master of Applied Science

Department of Civil Engineering

University of Toronto

2016

Abstract

The Ontario Ministry of Transportation (MTO) requires regional flood frequency equations to

determine peak flows of specific return periods, established using the data from gauged

locations, to design structures at the crossings of streams and rivers. This study intends to bridge

the gaps in the current estimation techniques used in Ontario and utilize the additional data to

improve its accuracy. Regional Flood Frequency Analysis (RFFA) of Ontario streams was

performed using multiple regression and the equations for the T-year flood quantile (2, 10, 25, 50

and 100 year) were developed. The results of the regression based Unified Ontario Flood Method

(UOFM) for the province reaffirms the conclusions of previous studies that peak discharge is

directly related to drainage area. Other factors such as the lake attenuation index, representative

of the area of lakes and wetlands, and climatological factors also contribute to the determination

of the peak discharge.

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Acknowledgments

Flood Frequency and statistics were strangers I never wanted to be friends with before

September 2014. A transfer to MASc brought along with it an opportunity to overcome my fears.

I owe the success of this work to Dr. Jennifer Drake. It wouldn’t have been possible without her

motivation and constant belief in me throughout the course of this project. Her countless

suggestions for my research and constructive feedback on my reports and thesis helped me to

achieve the results and the project could be completed in a short time span.

I would also like to thank the Ontario Ministry of Transportation, in particular Dr. Hani Fargaly,

for funding the project under its Highway Infrastructure Innovation and Funding Program

(HIIFP). Hani’s constant input of the user requirements and expectations were helpful in working

towards a simple solution for engineers and designers.

My achievement would not have been possible without the constant love and support of my

friends and family. The group lunch and coffee breaks became an important part of my day and

kept me going. Thanks to my friends Vivek, Balsher, Dikshant, Divyam and all others in GB415.

I would like to thank my brother Deepak for being there when I was tensed and encouraging me

to get back and fight it out. I am deeply indebted to my uncle and aunt, Dinesh and Sangeeta

Chhura for being my motivator and facilitator. They took such good care when I was new in

Canada and couldn’t support myself. My masters would not have been possible without their

support. This journey would have been difficult without my husband Pawan who took the

endless proofreading tasks I had for him and taught me the use of excel macros to speed up the

repetitive jobs. He loved me when I was impossible and this journey could have been longer, if

he was not there. I am grateful to my mother who has been my constant support and pillar of

strength. I credit her for the passionate woman I am today. I can never be grateful enough for

supporting my education even during the hard times. Last, but most importantly, Thank you

Papa for always being there. From where I see, you haven’t gone anywhere. Your love and

belief still inspires me to give my best without worrying about the results.

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Table of Contents

Acknowledgments .......................................................................................................................... iii

Table of Contents ........................................................................................................................... iv

List of Tables ................................................................................................................................ vii

List of Figures ................................................................................................................................ ix

Chapter 1 Introduction .................................................................................................................... 1

1.1 Background ......................................................................................................................... 1

1.2 Research Objectives ............................................................................................................ 2

1.3 Thesis Structure .................................................................................................................. 3

Chapter 2 Literature Review ........................................................................................................... 5

2.1 Background ......................................................................................................................... 5

2.2 Factors affecting Peak Flows .............................................................................................. 6

2.2.1 Physiography ........................................................................................................... 7

2.2.2 Climate .................................................................................................................... 9

2.3 Regional Analysis Procedures for Flood Frequency Studies ............................................ 10

2.4 Review of the Current Regional Flood Frequency Analysis (RFFA) Procedures ............ 11

2.4.1 RFFA Procedures for Ontario ............................................................................... 11

2.4.2 RFFA Procedures for Other Jurisdictions ............................................................. 15

2.5 Review of Available Data ................................................................................................. 18

2.5.1 Flow data ............................................................................................................... 18

2.5.2 Physiographic Data ............................................................................................... 22

2.5.3 Climatic Data ........................................................................................................ 23

2.6 Review of Statistical Analysis Methods ........................................................................... 23

2.6.1 Non-parametric testing .......................................................................................... 23

2.6.2 Station Frequency Analysis .................................................................................. 27

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2.6.3 Multiple Regression .............................................................................................. 30

2.7 Summary ........................................................................................................................... 32

Chapter 3 Methodology ................................................................................................................ 34

3.1 Data Collection ................................................................................................................. 34

3.2 Data Preparation and Screening ........................................................................................ 36

3.2.1 Estimating Annual Maximum Instantaneous (AMI) values for gaps in

historical records ................................................................................................... 36

3.2.2 Screening of HYDAT stations .............................................................................. 37

3.3 Data Analysis .................................................................................................................... 41

3.3.1 Non-parametric Testing ........................................................................................ 41

3.3.2 Station Frequency Analysis .................................................................................. 42

3.3.3 Multiple Regression Analysis ............................................................................... 44

3.4 Summary ........................................................................................................................... 46

Chapter 4 Results of Regional Flood Frequency Analysis ........................................................... 48

4.1 Unified Ontario Flood Method (UOFM) .......................................................................... 48

4.2 Illustration of Calculation Steps ........................................................................................ 50

4.3 Summary ........................................................................................................................... 52

Chapter 5 Verification and Evaluation ......................................................................................... 53

5.1 Verification of Regression Method: Application to Ontario ............................................ 53

5.2 Analysis of the UOFM for a Small Urban Watershed ...................................................... 56

5.3 Analysis of UOFM for Medium to Large Urban Watersheds .......................................... 57

5.4 Simulation for Peak Flow Estimation: Case of Urban Floods .......................................... 60

5.5 Comparison with Other RFFA Methods ........................................................................... 61

5.5.1 Comparison of UOFM and MIFM (South) ........................................................... 61

5.5.2 Comparison of UOFM and MIFM (Shield) .......................................................... 62

5.5.3 Comparison of UOFM and NOHM ...................................................................... 64

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5.6 Climate Change Considerations ........................................................................................ 65

5.7 Summary ........................................................................................................................... 65

Chapter 6 Conclusions and Recommendations ............................................................................. 67

6.1 Conclusions ....................................................................................................................... 67

6.2 Limitations and Recommendations for Future Studies ..................................................... 69

References ..................................................................................................................................... 71

Appendix A: Example of the Annual flow data for WSC ............................................................ 76

Appendix B: Summary of all HYDAT Stations ........................................................................... 79

Appendix C: Estimation of AMI flow data from AMAD flows ................................................... 90

Appendix D: Summary of results of Non Parametric Analysis .................................................... 92

Appendix E: Illustration of Station Frequency Analysis .............................................................. 99

Appendix F: Stepwise regression output from SPSS .................................................................. 102

Appendix G: Stations rejected from Multiple Regression Analysis ........................................... 143

Copyright Acknowledgement ..................................................................................................... 147

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List of Tables

Table 1: Function Classification and Design Flows (Source: Ontario Ministry of Transportation,

2008) ............................................................................................................................................... 6

Table 2: Relationship of Watershed Class with Class Coefficient (Joy & Whiteley, 1996) ........ 12

Table 3: Ratios to Flood Quantiles of Different Return Periods to the 25-year Quantile (Joy &

Whiteley, 1994) ............................................................................................................................. 13

Table 4: Summary of Previous Studies ......................................................................................... 16

Table 5: Example of Data from OFAT (Representative Station: 05PB018) ................................ 36

Table 6: Summary of the Difference in AIC ................................................................................ 43

Table 7: Correlation Matrix of Predictor Variables ...................................................................... 44

Table 8: Coefficients of the Regression Model and Output Summary ......................................... 48

Table 9: Range of Parameters used for Equation Development ................................................... 49

Table 10: Range of Quantile Estimates ........................................................................................ 50

Table 11: Verification Stations Parameters .................................................................................. 53

Table 12: Application of UOFM to Verification Stations ............................................................ 54

Table 13: Small Catchment Parameters ........................................................................................ 56

Table 14: Small Catchment Flood Quantiles ................................................................................ 56

Table 15: Medium to Large Urban Catchment Parameters .......................................................... 57

Table 16: Analysis Results for Medium to Large Urban Watersheds .......................................... 58

Table 17: Station Parameters for Comparison with MIFM (South) ............................................. 61

Table 18: Comparison of UOFM with MIFM (South) ................................................................. 62

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Table 19: Station Parameters for Comparison with MIFM (Shield) ............................................ 62

Table 20: Comparison of UOFM with MIFM (Shield) ................................................................ 63

Table 21: Station Parameters for Comparison with NOHM ......................................................... 64

Table 22: Comparison of UOFM with NOHM ............................................................................. 64

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List of Figures

Figure 1: Ecozones of Ontario (Source: Ecozone, 2012) ............................................................... 8

Figure 2: Isohyetal Map with Location of Environment Canada Weather Stations ..................... 10

Figure 3: Empirical Guidance Chart (Source: Watt et al. (1989)) ................................................ 18

Figure 4: Flow Data Comparison for a Typical Station (HYDAT station: 02HB021) ................. 20

Figure 5: Location of HYDAT Stations ........................................................................................ 35

Figure 6: Estimation of Missing Values of Instantaneous Peak (Sangal (1981)) ......................... 37

Figure 7: Location of Urban catchments ...................................................................................... 38

Figure 8: Delineation of an Urban Watershed with OFAT ........................................................... 38

Figure 9: Watershed Delineation Discrepancy in OFAT .............................................................. 40

Figure 10: Stations in the Hudson Plain ....................................................................................... 40

Figure 11: Stations Eliminated (non-compliant with nonparametric test hypotheses) ................. 42

Figure 12: Histogram for Q25 Quantile (dependent variable) ...................................................... 45

Figure 13: Regression Stations and Ontario Highways (Source: Highways, 2014) ..................... 46

Figure 14: Observed and Predicted Quantiles for Verification Stations ....................................... 55

Figure 15: Observed and Predicted Quantiles for Medium to Large Urban Watersheds ............. 59

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Chapter 1 Introduction

1.1 Background

Flooding of streams and rivers have been a concern for designers and policy makers for a long

time. The destructive nature and randomness of floods has often led researchers and engineers to

develop prediction tools for large flood events. The history of flooding in Ontario encompasses

many notable events, the most severe of which was Hurricane Hazel in 1954. Flooding caused by

Hurricane Hazel took 81 lives (mostly in the City of Toronto) while simultaneously leaving

thousands of Ontario residents homeless (TRCA, 2014). Property damages associated with this

event have been approximated at $100 million, which is about $1 billion today (TRCA, 2014).

Another notable severe flooding event occurred in May 1974 in the Grand River watershed.

Approximately, $6.7 million was assessed by Leach (1974) as residential, industrial and

municipal losses. In June 2004 a storm event in the Grand River watershed deposited 200 mm of

rain in a very short span of time causing severe flooding and excessive erosion

(Hebb and Mortsch, 2007). In 2013 both Alberta and Ontario experienced dramatic flooding of

Downtown, Calgary and the Don Valley Parkway, Toronto. The damages for these flood events

have been estimated at more than $1.72 billion and 465 million in insured losses for Southern

Alberta and Toronto, respectively (Insurance Bureau of Canada, 2015) Thus, floods have

become important and their prediction is pivotal for design of structures on our water courses.

Design floods are the peak flood discharge (or flow rates) which are critical when assessing the

risk and safety of hydraulic structures (e.g. culverts and bridge crossings), both planned and

existing. The prediction of these peak flood values during design of a hydraulic structure at water

crossing requires historical flow records at that location. These values are typically obtained at

gauging stations built on streams and rivers. However, it is common to encounter situations

where the location of interest lacks the associated historical stream flow data. For a water rich

province like Ontario it is not possible to have gauges on all water courses and, even for

situations where the stream is gauged, the point of interest may not coincide with the location of

the gauge station. Thus, when sizing bridges and culverts, engineers regularly depend on regional

analysis to estimate flood quantiles. Regional flood frequency analysis (RFFA) is performed to

develop relationships between flow estimates and relevant physiographic and climatic

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parameters of gauged streams in a hydrologically homogeneous region. These equations are

developed using the flow data available from the stream gauging stations. The resulting

relationships are used to predict flood quantiles at ungauged locations within the same region.

1.2 Research Objectives

Ontario currently uses a combination of different regional analysis methods for the design of

highway culvert and bridge crossings (Ontario Ministry of Transportation, 1997). Accepted

methods include the Modified Index Flood Method (MIFM) (Joy and Whiteley, 1996), the

Northern Ontario Hydrology Method (NOHM) (Watt, 1994) and the Rational Method. It was

observed that there are inconsistencies in the method which should be used based on the drainage

area of a watershed. For example, the MIFM cannot be applied for watersheds less than 25 km2.

The NOHM is applicable for drainage areas located in the Canadian Shield only and can only be

used for watersheds ranging from 1 km2-100 km

2. Also, both the MIFM (Shield) and the NOHM

can be used for drainage area ranging from 25 km2-100 km

2 in the Shield region of Ontario. Such

a situation creates the potential condition where none of the approved analysis methods are

suitable for an engineer’s design work (e.g. For a watershed of size approx. 13 km2 located in the

southern region of Ontario) or conversely, scenarios where multiple methods may be applied

(e.g. For a watershed of size 68 km2 located in the Shield region). During discussions with the

Ontario Ministry of Transportation (MTO), the requirements and analysis tools for the study

were finalized. The following points were identified as the limitations in the current RFFA

procedures that necessitated the need for this study.

1. Availability of approximately twenty years of additional stream flow data since the last

study of MIFM and NOHM completed in 1996 and 1994, respectively. The additional data,

when accounted for, will provide a better representation of the current watershed and stream

flow conditions.

2. Changes in catchment characteristics, which lead to gradual changes in the flow regime,

should be taken into consideration.

3. Inconsistency in area classification and the corresponding equation for prediction of flood

quantiles needs to be addressed.

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4. Analysis procedures for urban watersheds, predominately required for the south, are non-

existent. A review of the available data to ascertain the feasibility of such a study was

requested to be performed.

Thus, the objective of the study is to develop a simple and easy to use set of equations for

regional flood frequency analysis (RFFA). This thesis discusses the analysis procedures

undertaken and presents the results of the RFFA for Ontario.

1.3 Thesis Structure

The thesis presents the development of a unified method for prediction of peak flows for Ontario

streams and consists of six chapters. The contents of each chapter are presented below:

Chapter 1– Introduction

This chapter provides the background for the current research; identifies the research objectives

and provides a description of the thesis structure.

Chapter 2– Literature Review

This chapter provides a detailed review of the physiography, climate and hydrologic data for

Ontario. It also presents a review of relevant statistical literature and recent RFFA studies. This

establishes the foundation for the methodology used for the thesis and outlines the rationale of all

the subsections in the methodology.

Chapter 3– Methodology

This chapter describes the research methodology undertaken and presents the results obtained at

intermediary steps during the analysis work. The results of each step are also presented in this

section because, for majority of the cases, the subsequent step is dependent on the result obtained

at the previous step. For example, station frequency analysis is performed for only those stations

which were accepted during the non-parametric testing.

Chapter 4– Results of Regional Flood Frequency Analysis

This chapter presents the results of step-wise regression analysis to develop the Unified Ontario

Flood Method (UOFM). It also presents the design table developed for computation of peak

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flows for ungauged drainage basins for two regions of Ontario. The chapter highlights the

computation of the probable range for the predicted quantiles, established from the standard

errors of stepwise regression process, and illustrates an example calculation for UOFM.

Chapter 5– Verification and Evaluation

This chapter provides the results of the verification and evaluation of the UOFM equation for

predicting flood flows. A separate analysis was also performed to check the applicability of the

equations for urban watersheds. Finally, a comparison study was performed to check the

performance of the equations relative to the methods currently used in Ontario.

Chapter 6 – Conclusions and Recommendations

This chapter discusses the important conclusions of the thesis with respect to the research

objectives. Limitations of the current investigation and regression-based flood methods are

discussed. This may serve as the recommendations for additional research for improving the

peak flow estimates for Ontario.

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Chapter 2 Literature Review

The following sections provide an overview of the relevant literature related to Regional Flood

Frequency Analysis (RFFA) and the methods adopted for the current investigation. It provides a

background highlighting the need of RFFA procedures and its relevance to the MTO. It

subsequently discusses the factors which affect peak flows for any drainage catchment. This

section also reviews the methods currently used for regional analysis and reviews recent

investigations in various provinces of Canada and the United States. Subsequently, this section

reviews the available data and procedures for the development of RFFA equations through

multiple regression analysis.

2.1 Background

Provincial Highway Directive B-237 sets forth the MTO Drainage Management Policy and

Practice (Ontario Ministry of Transportation, 2008) for the province of Ontario. Ministry of

Transportation and Communication (MTC) as was known previously, now MTO has been

publishing its drainage design manuals since 1979. It has undergone several revisions since its

original publication and outlines the existing policies and design methodologies adopted by

MTO to date. In 1989, the MTO Drainage Management Technical Guidelines was prepared

which outlines the MTO standards and was used in conjunction with the drainage manual. Since

1997, the MTO has issued a single Drainage Management Manual (DMM) to replace the two

previous manuals. DMM includes the standards of practice and design methodologies but did not

include the drainage management policies guiding the practices and design. In 2008 MTO

published its Highway Drainage Design Standards (HDDS). This document outlines the existing

drainage design standards for components of highway infrastructure that have been adopted by

MTO over the years. The HDDS focuses on the highway surface drainage, water crossings and

storm water management for different components of the highway infrastructure. The HDDS

provides recommendations for the return period of design flows to be considered for various

highway classifications based on its function. The return period for various highway

infrastructures is summarized in Table 1.

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Table 1: Function Classification and Design Flows (Source: Ontario Ministry of

Transportation, 2008)

Functional Road

Classification

Return Period of Design Flows (Years)

Total Span (≤ 6 m) Total Span (> 6 m)

Freeway, Urban Arterial 50 100

Rural Arterial, Collector Road 25 50

Local Road 10 25

The MTO owns and operates approximately 2800 bridges across the province (Ontario Minstry

of Transportation, 2015). MTO requires peak flow estimates (flood quantiles) of various return

periods to size new hydraulic structures or for repair of existing structures. For design of these

structures, like brides and culverts, a return period is specified, for example T= 100 years for a

freeway bridge of more than 6 m span (Ontario Ministry of Transportation (2008),

Watt et al. (1989)). A return period of a flood may be defined as the average time between two

flood events of similar intensity. So, it may be expected that large flood events have large return

periods and vice-versa (Rao and Hamed, 2000). A T-year return period instantaneous flood has a

recurrence interval of T years or the annual probability of exceedance of p (=1/T). Thus, a 100

year flood has an annual exceedance probability of 1%. A flood quantile of T-year is the

magnitude of flood corresponding to the exceedance probability of p. Return period of the flood

to be considered for design purpose (design flood) is often decided based on the anticipated

design life of the structure in consideration among other factors such as highway class, annual

daily traffic (ADTs), importance of the structure, etc. (Watt et al. (1989), (Ontario Ministry of

Transportation, 1997)).

2.2 Factors affecting Peak Flows

The variation in climate, in combination with the physiographic parameters, produces unique

flood characteristics for different watersheds. The climate determines the flood generating

mechanism in a watershed, whereas physiography affects and distinguishes the response to the

climatic parameters. Thus, physiography and climate are both important factors which should be

considered while developing the regional flood frequency equations.

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2.2.1 Physiography

Physiography is an important determinant of the flood response for a drainage basin. Drainage

characteristics such as area, land use, storage and slope influence the hydrologic response to

floods and vary significantly throughout the province (Moin and Shaw, 1985). One of the earliest

investigations for Southern Ontario by Karuks (1961) identified the dependence of peak flows in

a catchment on the drainage area, storage factor, slope and the stream density. Further

investigations by Moin and Shaw (1986) for the whole of Ontario found the following

physiographic parameters as important: drainage area, slope of the channel, area of lakes and

swamps and the shape factor (parameters mentioned in the order of importance). Analysis by

Joy and Whiteley (1996) and Watt (1994), MIFM and NOHM respectively, concluded drainage

area to be the most significant determinant of peak flows. Other significant factors included the

slope, area occupied by lakes and swamps and the curve number. In recent years, urban flooding

has also become a common and costly phenomenon throughout the province. The

imperviousness associated with the urban environment decreases its ability to absorb and allow

infiltration of rainfall. This change causes more peaked floods than an equivalent rural

environment.

Homogenous region classifications have the inherent assumption that watersheds within a region

exhibit similar hydrologic properties and behavior. The assimilation of information together from

gauged stations within a homogenous region provides a better estimate of the flood quantiles

when the information is transferred to ungauged points of interest during regional analysis. Thus,

delineation of homogeneous regions in a geographical area is an important step before

proceeding with regional flood frequency analysis. Various homogeneous region classifications

have been proposed for Ontario in previous studies based on different criterion (e.g. Moin and

Shaw (1985), Moin and Shaw (1986), Gingras et al. (1994)). The homogenous regions employed

in these flood regression studies are based on (1) flood characterestics (by computing of

regression residuals) up to and including the data till the 1980’s and/or 1990’s, (2) grouping the

regions based on homogeniety tests or (3) the peak flood generating mechanism. Since flood

characteristics may change over time a more general method of regional classification is

required. A classification by the National Ecological Framework identifies the ecozones in

Canada. This classification is based on dividing large geographical units with an ecosystem

perspective. These divisions, called ecozones, depict regions of broadly similar climatic and

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geological characteristics (Wiken, 1995) and do not depend on the flood data for this

classification, unlike previous studies like Moin and Shaw (1986) and Gingras et al. (1994)).

Thus, it can also provide a common index for comparison of climate and related phenomenon

within Ontario across different research areas. According to the classification, Ontario is divided

into three ecozones shown in Figure 1. The three ecozones present in Ontario are the Hudson

Plains, Boreal Shield and Mixed Wood Plains.

Figure 1: Ecozones of Ontario (Source: Ecozone, 2012)

The Hudson Plain ecozone, located in Northern Ontario, has large portions of its land cover in

the form of wetlands. This is a result of poor drainage creating a high degree of water retention

throughout the region (Moin and Shaw, 1985). This ecozone has sedimentary bedrock which

gradually drains to the Hudson Bay and James Bay (Wiken, 1995). The Boreal Shield ecozone is

dominated by the Canadian Shield and forest vegetation. The Shield has a thin soil cover over

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the rocks, resulting in rapid flows in the streams (Moin and Shaw, 1985). It is also characterized

by large natural storages in the form of lakes and wetlands which attenuate flows

(Moin and Shaw, 1985). The Mixed Wood Plains represent one of the most fertile and

productive ecozones of Canada and most of the urbanization has concentrated in this region

(Wiken, 1995). The soil in this region is well drained and has marshes which provide some

storage to runoff (Moin and Shaw, 1985).

2.2.2 Climate

The climatology across Ontario varies and so do the flood causing mechanisms. Flooding occurs

due to various climatic and hydrologic factors such as snowmelt, spring rainfall, thunderstorms,

hurricanes, ice jams and/or a combination of these factors (Gingras et al. (1994),

Moin and Shaw (1985)). Spring rainfall is the most common cause of flooding across the

province (Moin and Shaw, 1985). The recent floods due to spring rainfall in Peterborough in

June 2004 caused damages in millions of dollars (City of Peterborough , 2005). The 49th

parallel

storm in June 2002, also due to excessive precipitation (approximately 400 mm) caused severe

flooding in north-western Ontario and other parts of Canada and the United States. It caused

damages in excess of $31 million, impacted infrastructure and also affected the local First Nation

communities (Hebb and Mortsch, 2007). Thus, climate and specifically precipitation is a variable

factor throughout the province and its various forms determine the flood causing mechanism.

The isohyetal map presented in Figure 2 shows the variation of mean annual precipitation across

the province. This is based on the data from Climate Normals published by Environment Canada

for 151 weather stations across Ontario from 1981-2010. Average annual precipitation ranges

from less than 700 mm in the northwest part of the province to more than 1250 mm in the

“snowbelt” east of Lake Huron.

Previous studies (Karuks (1961); Moin and Shaw(1986)) have identified the precipitation over a

region as an important determinant of the observed stream flows. However, in the currently used

regional analysis methods, NOHM and MIFM, precipitation over a drainage catchment was

either not considered or found to be statistically insignificant during the investigation procedures

by Watt (1994) and Joy and Whiteley (1994). In contrast most American studies such as

Capesius and Stephens (2009), Waltemeyer (2008) and Landers and Wilson (1991) for the states

of Colarado, New Mexico and Mississippi, respectively, as well as studies for Maritime

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provinces Newfoundland (Rollings, 1999) and New Brunswick (Aucoin et al. 2011) all consider

precipitation to be a crucial parameter for predicting peak flows.

Figure 2: Isohyetal Map with Location of Environment Canada Weather Stations

2.3 Regional Analysis Procedures for Flood Frequency Studies

Statistical analysis of long term stream flow records are considered the best source of

information to predict future events of a specific return period (Joy and Whiteley, 1996). Two

analysis procedures have historically been applied to regional flood frequency analysis in

Ontario: index flood method and the multiple regression method. Index flood method was

traditionally the most popular method of estimating peak flows and was used in most Canadian

provinces during the 1960s and 70s (Watt et al., 1989). This method involves developing a

relation between physiographic parameters with an ‘index flood’, usually the mean annual flood.

A frequency curve relates this index flood to any other T-years flood quantile. The index flood

method assumes a single shape or slope of this frequency curve within one region. This

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assumption does not hold for situations where there are large storage effects (Watt et al., 1989)

which have an attenuation effect on peak flows. The second technique, called the multiple

regression involves developing a regression based relation between the peak flows of different

return periods or the mean annual flow and the physiographic and/or climate parameters using

various regression procedures. Multiple regression and its various procedures are discussed in

detail in Section 2.6.3.Watt et al. (1989) identified direct regression of quantiles of different

return periods as an improvement over index flood method. Regression based methods have a

limitation on their applicability and should only be applied to watersheds with basin

characteristics within the range of those used for the development of the regression equation

(Watt et al. 1989). Additionally, the data should represent natural flow conditions and the

equation should not be applied to watersheds with basin characteristics outside of the range of

parameters used to develop the equations. Regression based methods have also started to have

wider acceptability in various provinces of Canada and the United States. Watt et al. (1989)

mentions the studies based on direct regression of quantiles in the late 1980s. Other recent

examples include Waltemeyer (2008) for New Mexico, Capesius and Stephens (2009) and Vaill

(2000) for Colorado, Eash (2001) for Iowa; Rollings (1999) for Newfoundland,

Aucoin et al. (2011) for New Brunswick and Sandrock et al. (1992) for Saskatchewan. All of

these reports use a regression based approach for determination of flood quantiles.

2.4 Review of the Current Regional Flood Frequency Analysis (RFFA) Procedures

2.4.1 RFFA Procedures for Ontario

The MTO Drainage Management Manual (Ontario Ministry of Transportation, 1997) outlines the

procedures for regional flood frequency analysis allowed for the design of provincial highway

culverts and bridge crossings. Currently, the methods used in Ontario are the Modified Index

Flood Method (MIFM) and the Northern Ontario Hydrology Method (NOHM). A review of

these methods is presented below.

2.4.1.1 Modified Index Flood Method

The Modified Index Flood Method (MIFM), presented in Joy and Whiteley (1994) and

Joy and Whiteley (1996), is based on the basic form of the Index flood equation used for the

estimation of the mean annual flood. The procedure is modified for prediction of Q25 quantile

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and its implementation is illustrated in the drainage management manual (Ontario Ministry of

Transportation, 1997). The MIFM requires estimates of the Curve Number (CN) to compute its

corresponding Base Class.

Base class = −5.64 + 0.191 ∗ CN Equation (1)

The channel slope and storage are then used to compute the adjustments in the base class and the

adjusted watershed class is calculated.

𝑆𝑙𝑜𝑝𝑒 𝐴𝑑𝑗𝑢𝑠𝑡𝑚𝑒𝑛𝑡 = 1.815 ∗ [{𝑆𝑊

0.004}

0.5

− 1] Equation (2)

𝑆𝑡𝑜𝑟𝑎𝑔𝑒 𝐴𝑑𝑗𝑢𝑠𝑡𝑚𝑒𝑛𝑡 = −0.1142 ∗ 𝑆𝐴 Equation (3)

where SW = the slope of the drainage basin (dimensionless); SA =Storage Area (%)

𝐴𝑑𝑗𝑢𝑠𝑡𝑒𝑑 𝑊𝑎𝑡𝑒𝑟𝑠ℎ𝑒𝑑 𝐶𝑙𝑎𝑠𝑠 = 𝐵𝑎𝑠𝑒 𝐶𝑙𝑎𝑠𝑠 + 𝐴𝑑𝑗𝑢𝑠𝑡𝑚𝑒𝑛𝑡𝑠 Equation (4)

A range has been established (Table 2) for the adjusted class and the associated class coefficient

and the final class coefficient is ascertained by interpolation.

Table 2: Relationship of Watershed Class with Class Coefficient (Joy & Whiteley, 1996)

Watershed Class Class Coefficient, C

1 0.15

2 0.22

3 0.31

4 0.44

5 0.63

6 0.90

7 1.29

8 1.84

9 2.62

10 3.74

11 5.34

12 7.63

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The Modified Index Flood Method (MIFM) calculates the 25 year flood quantile from Equation

(5). The 2.33-year, 5-year, 10-year, 50-year and 100-year quantile are calculated from the

established ratios (Table 3).

𝑄25 = 𝐶25 ∗ 𝐴0.75 Equation (5)

where C is the class coefficeint and A is the total drainage area (km2).

Table 3: Ratios to Flood Quantiles of Different Return Periods to the 25-year Quantile (Joy

& Whiteley, 1994)

Basin Type Return Period (yrs)

2.33 5 10 25 50 100

Non Detentive type Southern

Basins 0.49 0.66 0.81 1.00 1.16 1.32

Shield and Detentive type

Southern Basins 0.57 0.71 0.84 1.00 1.13 1.27

North Shores of Lake Erie and

Ontario 0.41 0.62 0.79 1.00 1.16 1.32

The advantage of MIFM is its applicability to drainage areas in both the Shield type and

Southern drainage basins. It is however restricted in watershed size and cannot be used for

drainage areas less than 25 km2. The classification of basin types presented in Table 3 is used as

a design chart by MTO. However, the definitions of detentive and non-detentive basins are not

explicitly stated in Joy and Whiteley (1994), Joy and Whiteley (1996) and Ontario Ministry of

Transportation (1997), which creates a situation of uncertainty for engineers and designers. Also,

the computation of CN can also be challenging for rapidly urbanizing watersheds. The flow

predictions for these watersheds may not be close to the observed flows due to the urban flood

control measures within a drainage basin. An example in Joy and Whiteley (1996) predicted the

change in peak flow by approximately four times ( from 12 m3/s to 46 m

3/s) when the CN is

increased by 10 units (from 60 to 70) for a medium sized watershed (60 km2) located in Southern

Ontario. The sensitivity of flow prediction to CNs necessitates tools and methodologies for its

accurate estimation in a drainage basin. These are not yet available for the province of Ontario.

Thus, CN estimates depend on the judgement of the project engineer. The MIFM prediction for a

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Shield type basin, however, does not require CN estimate and the watershed class is calculated

from the percentage of water detention. As per the procedures for MIFM (Shield), the calculation

of percentage of water detention considers the area of lakes and wetlands only if the total

drainage area is greater than 100 km2. It does not consider the area of lakes and wetlands for

smaller watersheds.

2.4.1.2 Northern Ontario Hydrology Method

The Northern Ontario Hydrology Method (NOHM) (Watt,1994) is a regression based estimation

of the mean annual annual flood from the distribution parameters (the mean, standard deviation

and skewness). These distribution parameters are related to the basin characteristics. A frequency

factor relation is used to determine the other quantiles of interest from the assumed regional

distribution (Watt, 1994). The calculation of peak flow is illustrated from Equation (6) to

Equation (12). A T-year maximum daily flow value is calculated from Equation (9). A peaking

factor (P) is calculated and applied which is based on the outlet point and if it is a lake outlet

Equation (11) is chosen. The peaking factor is used to compute the maximum instantaneous

peak from Equation (12).

𝑄𝑚 = 0.170 ∗ 𝐴1.06 ∗ (1 −

𝐴𝑑

𝐴)

2.07

Equation (6)

𝐶𝑣 = 0.502 ∗ (1 −

𝐴𝑑

𝐴)

1.85

Equation (7)

𝐶𝑆 = −2.52 + [3.73 ∗ (1 −

𝐴𝑑

𝐴) Equation (8)

If Cs is < 0.5 then its value is set as 0.5

where Qm is the mean annual flood (m3/s), Cv is the coefficient of variation, Cs is the coefficient

of skew, Ad is the area of lakes and swamps (km2) and A is the total drainage area (km

2).

𝑄𝑇 = 𝑄𝑚 (1 + 𝐾(𝑇,𝑔) ∗ 𝐶𝑣) Equation (9)

𝑃 = 1 + exp [−22 ∗ (𝐴𝑑

𝐴− 0.06)] Equation (10)

Or

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𝑃 = 1 + 6 ∗ 𝐴−0.36 ∗ exp [−22 ∗𝐴𝑑

𝐴] Equation (11)

𝑄𝑝,𝑇 = 𝑃𝐹 ∗ 𝑄𝑇 Equation (12)

Where QT is the T-year maximum daily flow, K(T,g) is the frequency factor;

P is the peaking factor and Qp,T is the peak flow with a T year return period.

The advantage of NOHM is that it is developed specifically for the Shield region where large

storages affect the rainfall-runoff response (Ontario Ministry of Transportation, 1997). However,

this method is only applicable to watersheds with drainage areas between 1-100 km2. The small

dataset used for the study (11 hydrometric stations) limits the accuracy to a regression based

method to observed flows in a larger geographic region. At the same time, the verification study

was not extended to stations which were not a part of the analysis. Also, as discussed in Section

2.2.2, precipitation is an important parameter which varies across the province and was not

considered during the development of NOHM.

2.4.2 RFFA Procedures for Other Jurisdictions

Flood frequency relationships are required by designers and planners for reliable and accurate

prediction of flood discharge, cost effective planning and safe designs of structures located on

water courses. Various other studies have been conducted in other provinces across Canada and

the United States. Most of these studies utilize data from a station having a minimum of 10 years

of record length to predict peak flows of up to 100 years. Few Canadian studies have been

utilizing non parametric testing to assess the quality of data obtained from stream gauging

stations. However, none of the reviewed studies from the US consider non parametric screening

to analyze data quality. Table 4 provides an overview of the most recent studies from Canada

and the United Stated. All the studies presented in Table 4 conclude drainage area as the most

important parameter for determination of peak flows.

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Table 4: Summary of Previous Studies

Province Reference

Min. no.

of record

years

No of

stations

used

Range of

Drainage

Area Used

Predictors considered Regulation

Non-

Parametric

Screening

Canadian Provinces

New

Brunswick

Aucoin et

al., 2011 11 56

3.89 km2 -

39,900 km2

Drainage area, mean annual

precipitation No No

Newfoundland Rollings,

1999 10 70

3.63 km2-

4,400 km2

Drainage area, amount & location of

natural storage, watershed slope,

watershed shape, soils, vegetation,

land use

No Yes

Saskatchewan Sandrock et

al., 1992 11 33

10 km2-

350 km2

Drainage area, drainage density,

slope, watershed relief and shape

factor

No No

United States

Iowa Eash, 2001 10 291 1.3 mi

2-

5452 mi2

Drainage area, main channel slope,

ratio of basin area within des moines

lobe landform region to the total

drainage area

No No

Colorado Capesius et

al., 2009

10

422

0.5 mi2-

5250 mi2

Drainage area, mean watershed

elevation, Mean watershed slope, %

drainage area above 7,500 feet

elevation, mean annual precipitation,

and 6-hour, 100-year precipitation.

No No

North

Carolina

Pope et al.,

2001 10 317

0.1 mi2-

8671 mi2

Drainage area, channel length,

channel slope, basin Slope, Shape No No

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Province Reference

Min. no.

of record

years

No of

stations

used

Range of

Drainage

Area Used

Predictors considered Regulation

Non-

Parametric

Screening

New Mexico Waltemeyer,

2008 10 293

0.059 mi2-

12,7000 mi2

Drainage area, basin slope upstream,

basin elevation, maximum

precipitation intensity ( storm of 24-

hour & recurrence interval 100

years, mean annual precipitation

No No

Illinois Soong et al.,

2004 10 288

0.03 mi2-

9554 mi2

Drainage area,

main channel slope, average

permeability, % area of open water

& wetland, basin length, basin width,

main-channel length, & 2-day, 24-

hour rainfall depth

No No

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2.5 Review of Available Data

2.5.1 Flow data

Flood series, depending on the record length and the purpose of the study can be using two

different approaches for flood frequency analysis: Peak over Threshold (POT) and Annual

Maximum Series (AMS). The AMS consists of a single maximum value (either the instantaneous

peak or the average daily value) recorded over a given year. It may be used if the data records

available for a stream gauging station have sufficient record length. Watt et al. (1989) argues that

the minimum number of record years considered for flood frequency studies should depend on

the intended extrapolation from the flow series. An empirical guidance chart is provided in Watt

et al. (1989), Chapter 5 Figure 5.3.

Figure 3: Empirical Guidance Chart (Source: Watt et al. (1989))

The chart (reproduced in Figure 3) illustrates that for short length of stream records and

prediction of large design floods, reliance on only station frequency analysis should not be

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preferred. On reading the design chart it can also be inferred that while performing station

frequency analysis a record length of 10 years may be sufficient to predict a design flood of

approximately 50 years. However, to predict a 100 year design flood, the record length should be

approximately 25 years. Thus, it is important to use judgement for a balance between the

minimum acceptable record length, degree of extrapolation required and uncertainty in the

prediction of flood quantile.

The Annual Maximum series may sometimes lead to loss of information as only a single peak

flow of a given year is considered and the subsequent second or third peak of the same year are

ignored. These subsequent flows, ignored in AMS series, may be greater than the peak flows of

other years (Rao and Hamed, 1999). On the contrary, POT consists of all data / flow records

above a given threshold level that may be selected based on the number of available records and

the selected threshold. It is generally used when the record length is short. The inter event time

between POT events is also not equal. A minimum inter event time may be selected to ensure the

independence of the data series. Adamowski (2000) observed that the POT models are not useful

in the analysis of events which results from more than one flood causing mechanism like

combination of spring rainfall, snowmelt, thunderstorms etc. The condition of bimodal data may

not be new to the climatic conditions in Ontario where flooding may occur due to a combination

of different mechanisms (Moin and Shaw (1985), Gingras et al. (1994)). Thus, if sufficient data

is available, AMS series can be considered for analysis of streamflow data.

Water Survey of Canada (WSC) collects hydrometric data at its stream gauging stations across

Canada. Its central database, HYDAT, contains flow data such as daily and monthly mean flow,

water levels, sediment concentration, peak flow etc. WSC operates 2,500 gauging stations across

Canada. Achieved data of approximately 5,500 stations is also stored in HYDAT (Environment

Canada, 2011). Reference Hydrometric Basin Network (RHBN) is a subset of the national

network which is available for long term hydrological monitoring. These stations are a part of the

Global Climate Observing System (GCOS) and the long term flow records available from RHBN

stations maybe useful while dealing with pressing issues like climate change phenomenon.

The average flow recorded over a day, referred to as the average daily flow, and instantaneous

peak flows are reported at stream gauging stations throughout Ontario in the HYDAT database.

For a given stream gauge, an Annual Maximum Average Daily (AMAD) dataset reports the

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maximum value of the average daily flows recorded for each year of the historical stream record.

A single maximum instantaneous flow value recorded over a year is also reported as the Annual

Maximum Instantaneous (AMI) flow. For RFFA, AMAD data series are generally used if AMI

data series are not available. If AMAD series is used for flood frequency studies it is

recommended to apply a peaking factor to the predicted T-year quantiles (Watt 1994). As evident

from Figure 4, which provides a comparison of AMI and AMAD values for a representative

station it is evident that the values of AMAD can vary considerably in relation to the AMI flow

data. It may be observed that AMI flow data provides a better representation of the peak flow

conditions in a drainage basin and should ideally be selected if sufficient records are available.

This view has also been supported by previous studies such as Sangal (1981).

Figure 4: Flow Data Comparison for a Typical Station (HYDAT station: 02HB021)

2.5.1.1 Estimating Peak Flow from Mean Daily Flow

Historically, numerous procedures such as the Fullers Method and Langbein’s Approach

(Moin and Shaw, 1985) have been used to predict instantaneous peak flows from average daily

flows when gaps in the stream record exist. Watt et al. (1989) suggest that the missing or

incomplete flow data may be ascribed to two reasons: broken series or incomplete records. When

a broken series is not related to the magnitude of the event, such data, with gaps, may be

combined and used as a single dataset. An incomplete record on the other hand is when an

extreme event has left the gauging station un-operational. Such missing events should be

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estimated based on information by the recording agency. Application of estimation procedures is

particularly important when either the data series is not of adequate length or is not available in

the form to be utilized for peak flow estimation. Flow recordings and flood frequency studies up

until the early and mid-90s were mostly based on AMAD flow data as this was the only recorded

data available for a long time. With the advent of data recorders which can record values at 15

minute interval, currently there are a large number of stations with appreciable length of AMI

flow data. To extract information for early station years Sangal (1981) investigated the Fuller’s

and Langbein’s method and thereby developed a procedure which was specifically applied to

Ontario’s context.

1. Fuller’s Method is based on the data for 24 drainage basins from Eastern United States uptill

1914. He plotted the ratio of ((Qp- Qm)/ Qm) with the drainage area on a log-log scale and

derived a curve with the following relationship.

𝑄𝑝 = 𝑄𝑚( 1 + 1.5𝐴−0.3) Equation (13)

where Qp is the peak and Qm is the mean flow and A is the drainage area (km2).

Sangal (1981), after investigation, opined that this method represents a statistically poor

relationship with an R2 of 0.48 but it continues to be used due to a lack of alternative

approaches.

2. Langbiens Approach: This method uses the data of mean flows for three consecutive days

(Q1, Q2 (or Qm) and Q3; where the mean annual flow is the flow of the second day), the peak

flow (Qp) and the time for the peak. The ratio of the Qp and Qm are described as functions of

Qm/Q1 and Qm/Q2. Thus, for similar ratios of the flows for the three consecutive days,

Langbiens approach gives similar ratios for Qp and Qm. This method therefore neglects any

effect of the size of drainage catchment (Sangal, 1981; Moin and Shaw, 1985).

3. Sangal’s Method: Sangal (1981) has put forth a procedure, which is an extension of the

Langbiens concept, for determination of peak flows from average daily flows. This method

has been developed and successfully applied for Ontario’s context in previous flood frequency

studies by Moin and Shaw (1985) and MNR (2014). Sangal (1981)’s procedure for prediction

of missing AMI flow values also uses the average daily flow for three consecutive days (Q1,

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Q2 and Q3). The second position (Q2) is occupied by the AMAD flow value of the year. A

parameter called the base factor K is also employed in the study by Sangal (1981) which is the

base of the assumed triangular hydrograph. Equation (14) depicts the general form of the

relation between the instantaneous peak flow and average daily flow for any year. For the

station years having both AMI and AMAD flow data, Equation (14) was employed to

estimate the base factor (K) for the year. For the current study, the average of the base factor

for all the years was adopted as the base factor for the station. The station base factor was

subsequently used in Equation (15) to predict the AMI values for any given year which had

the AMAD flow data available.

𝐾 = (4𝑄2 − 2𝑄1 − 2𝑄3)/(2𝑄𝑃 − 𝑄1 − 𝑄3) Equation (14)

QP′ = (Q1 + Q3)/2 + [2Q2 − Q1 − Q3]/K Equation (15)

Where, QP = peak flow (m3/s); QP' = predicted peak flow (m

3/s), Q1, Q2 and Q3= mean daily

flow (m3/s) for 3 consecutive days where Q2 represents the AMAD value of the year.

Sangal (1981) study yielded 79% of predicted peaks within ±20% of their actual values for

Ontario demonstrating that it as an effective method for predicting AMI flows. Sangal (1981)

provides the value of the parameter K for 387 watersheds in Ontario, which can be used during

estimating the peak flows for situations when the K value cannot be predicted. However, in the

current dataset of stream flow records most station years have both AMI and AMAD data. Thus,

it was possible to estimate K values for all individual watersheds used in this study instead of

using the K values provided in Sangal (1981).

2.5.2 Physiographic Data

Ontario’s physiographic data is accessible through the Ministry of Natural Resources and

Forestry (MNR)’s web-based Ontario Flow Assessment Tool (OFAT), the use of which is

increasing in the province of Ontario. OFAT can compute watershed boundaries and site specific

hydrologic information. OFAT 1 was released in 2002 as an add-on to GIS software (MNR,

2015). The current version 3 of OFAT is web based which utilizes the digital elevation models to

delineate the contributing drainage area at any point of interest. It also computes ten associated

physiographic characteristics along with the land cover information for and selected point of

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interest. The land cover information from OFAT is extracted from the land cover maps of

Ontario which combines the compilation from Provincial Land Cover Database, Far North Land

Cover and the Southern Ontario Land Resource Information System. Additionally, OFAT III

runs various Hydrology models at ungauged points of interests to calculate stream flow at these

locations. A limitation of OFAT is that it assumes natural flow condition and any regulation in

flow are not considered. A review of the data from OFAT is provided in Table 5.

2.5.3 Climatic Data

Climatic factors like precipitation determine the flood causing mechanism in a catchment.

Environement Canada provides Climate Normals which summarize average climatic information

of a given weather station. Climate Normals are updated every 10 years to represent the climatic

conditions for the last 30 years. Precipitation information at its weather stations is provided

within the climate normal dataset. The mean annual precipitation is the total amount of rainfall

and snowfall over the year. However, the value of mean annual precipitation, as the predictor of

flood, is required at the point of interest, i.e. the stream gauging stations. Various interpolation

techniques can be employed to interpolate the mean annual precipitation at ungauged locations.

Empirical Bayesian Kriging (EBK) is a geo-statistical Interpolation method which helps to make

predictions at unknown locations using values at known locations. EBK takes into account the

errors introduced by the variance of difference between two locations (Environmental Systems

Research Institute, Inc. (ESRI), 2012). Thus, EBK has an inherent advantage over other

interpolation methods, like inverse distance weighing (IDW), which tend to underestimate the

standard errors of prediction. Interpolation techniques are generally used for preparation of

isohyetal maps for region. It has also been widely used in flood frequency analysis in the United

States to prepare skew maps in various provinces like Illinois and Iowa (Soong et al. (2004),

Eash (2001)).

2.6 Review of Statistical Analysis Methods

2.6.1 Non-parametric testing

The underlying assumptions associated with the time series for RFFA is that the dataset is

random, homogeneous, independent and stationary (Watt (1994), Rao and Hamed (2000)). Thus,

compliance with these conditions is a pre-requisite for any statistical analysis. Non-parametric

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testing does not assume any underlying distribution and the evaluation are based on assigning

ranks to the dataset. These tests help in ensuring that a probabilistic model applies to the dataset

(Watt, 1994). The necessity of these tests has also been highlighted in Watt et al. (1989) and Rao

and Hamed (2000). The compliance with the aforementioned assumptions has also been tested in

previous studies like Watt (1994), Moin and Shaw (1985) and MNR (2014). The description of

these tests, given in Appendix A & B of Ottawa River Flood Mapping (1984) and Rollings

(1999), is reproduced in the subsequent sections. The hypotheses for all the tests are generally

accepted at either 1% or 5% significance level. Though Watt (1994) recommends these statistical

testing, rejection of the non-parametric hypothesis is not necessarily a strong evidence of

nonconformity with the statistical assumptions and, as such, rejected cases may require further

investigation. This could involve examining changes in the drainage basin for the beginning and

the end of the record period for urbanization, or changes in flow or storage.

2.6.1.1 Test for Independence

Independent events are those where the probability of occurrence of one of the event does not the

affect the probability of occurrence of the second event (Rollings, 1999). Thus, it tests the

significance of correlation coefficient between N-1 pairs of ith and (i+1)th event. The significance

of the correlation coefficient helps in establishing the independence of the data series

(Rollings, (1999), Ottawa River Flood Mapping (1984)). Pearson coefficient has an underlying

assumption of a normal sampling distribution. Thus, for flood frequency studies where a single

distribution cannot be ascribed to the dataset with certainty, a non-parametric form based on

ranking of dataset is used Ottawa River Flood Mapping (1984). Spearman rank order serial

correlation coefficient for independence, detailed in in Ottawa River Flood Mapping (1984) and

(Rollings, 1999) is used to test the assumption of independence for the dataset of each station.

The null hypothesis for the test is that the two series are independent. The process is illustrated

below:

The data series Q1, Q2, Q3………Qn-1 is represented in chronological order and xi denoting the

ranks of Qi. Similarly, Q2, Q3………Qn is represented in chronological order and yi denoting the

ranks of Qi.

The spearman rank order serial correlation coefficient is given as:

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𝑆1 =1

2 ( ∑ 𝑥𝑖

2 + ∑ 𝑦𝑖2 − ∑ 𝑑𝑖

2) (∑ 𝑥𝑖2 ∑ 𝑦𝑖

2)−

12 Equation (16)

∑ 𝑥𝑖2 =

𝑚3 − 𝑚

12− ∑ 𝑇𝑥 Equation (17)

∑ 𝑦𝑖2 =

𝑚3 − 𝑚

12− ∑ 𝑇𝑦 Equation (18)

where di is difference in rank of xi and yi ; m=N-1and summation is taken for m pairs of xi and yi.

The moment of T adjusts for the tied ranks and is calculated as follows:

𝑇𝑥 =𝑟3 − 𝑟

12 Equation (19)

where r is the number of observations tied at a given rank. ∑ Tx 𝑎𝑛𝑑 ∑ Ty are then extended to

all the tied ranks.

For N less than 10, special tables are available for defining the region of rejection for S1 at given

significance level. When N is 10 or greater, then the function t is distributed like students t and a

one tail test is used to test the significance of the hypothesis.

𝑡 = 𝑆1 [𝑚 − 2

1 − 𝑠12]

1/2

Equation (20)

2.6.1.2 Test for Stationarity

The land use conditions of a watershed change with time thereby causing changes in flow data

series. If flow conditions are changing with time, a trend in the flow series may be observed.

Spearman rank order correlation coefficient is used to test the stationarity of the data set. The test

process from Ottawa River Flood Mapping (1984) is illustrated below. The null hypothesis for

the test states that the the there is no trend or serial correlation between the dataseries.

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The data series Q1, Q2, Q3………Qn is represented in chronological order and yi denoting the

ranks of Qi . Similarly, 1, 2, ……N is represented in the sequential order and xi denoting the

ranks of Qi.

The spearman rank order correlation coefficient, illustrated in Ottawa River Flood

Mapping (1984), is computed as:

𝑟𝑠 =1

2 ( ∑ 𝑥𝑖

2 + ∑ 𝑦𝑖2 − ∑ 𝑑𝑖

2) (∑ 𝑥𝑖2 ∑ 𝑦𝑖

2)−

12 Equation (21)

where Equation (17) and Equation (18) are used to compute the value of ∑ 𝑥𝑖2 𝑎𝑛𝑑 ∑ 𝑦𝑖

2.

Here di is difference in rank of xi and yi; m=N; summation is taken for m pairs of xi and yi and

∑ 𝑇𝑥 = 0 and ∑ Ty is calculated as in Equation (19).

For N less than 10, special tables are available for defining the region of rejection for 𝑟𝑠 at given

significance level. When N is 10 or greater, then the function t is distributed like students t. The

null hypothesis states that there is no trend either upward or downward so a two tail test is used

to test the significance of the hypothesis.

𝑡 = 𝑟𝑠 [𝑁 − 2

1 − 𝑟𝑠2

]1/2

Equation (22)

2.6.1.3 Test for Homogeneity

Homogeneity tests take into consideration any abrupt changes in the drainage basin, like

construction of a reservoir etc., by analyzing two sub samples from the drainage basin (Rollings,

1999). Mann-Whitney split sample test is used to ascertain the homogeneity of the sample. The

condition of non-homogeneity may be possible in hydrology due to natural as well as

anthropogenic reasons (Ottawa River Flood Mapping, 1984). The procedures for the Mann-

Whitney test, highlighted below, help in identification of non-homogeneous flood series. The

null hypothesis of the Mann Whitney U-test is that the two samples are from the same population

(homogeneous).

The sample is split into two sub-samples and ranks are assigned. The Mann-Whitney U statistic

is computed. It is defined as the smaller value of U1 and U2.

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𝑈1 = 𝑛1𝑛2 +𝑛1(𝑛1 + 1)

2− 𝑅1 Equation (23)

𝑈2 = 𝑛1𝑛2 − 𝑈1 Equation (24)

where n1(smaller sample) and n2 are the sample size ; R1 is the sum of ranks in n1.

The significance of U is ascertained by assessing the critical values and the associated regions of

rejection which have been tabulated and published. For large sample size, a normal variate z

(0,1) as Equation (25) and the associated regions of rejection at different significance levels are

analyzed.

𝑧 = 𝑈 −

𝑛1𝑛2

2

{[𝑛1𝑛2

𝑁(𝑁 − 1)] [(

𝑁3 − 𝑁12 ) − ∑ 𝑇]}

1/2 Equation (25)

2.6.1.4 Test for Randomness

Runs test, performed by calculating the runs below and above the median, is used to test the

randomness of the flow series for each station (Moin & Shaw, 1985). A run is a group of data

items which follow a sequence with similar adjacent elements. The runs test designates the data

into two different categories with values above and below the median (SPSS Statistics 21 Help,

2012). The number of ordered sequence of each group gives the runs in the sample. The null

hypothesis for runs test is that the sequence is random. The significance associated with the

number of runs helps decide the acceptance or rejection of the hypothesis (Mathworks, 2015).

2.6.2 Station Frequency Analysis

Station frequency analysis is performed for gauged locations in a hydrologically homogeneous

region and the value of the flood quantiles is determined. This process is performed by fitting

theoretical probability distribution curves to the dataset and the fitted distribution is used to

compute the quantile values associated with a particular exceedance probability. Several

theoretical probability distributions have been proposed for fitting annual maximum flow data

including Normal, Lognormal, 3-Parameter Lognormal, Gumbel, Pearson type 3, Log Pearson

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type 3 and the Generalized Extreme Value (Watt et al., 1989). Historically, a 3-Parameter Log

normal distribution has been adopted for studies like Moin and Shaw (1985) and Joy and

Whiteley (1994) in the province of Ontario Similarly, Log-Pearson type 3 has been an accepted

probability distribution in the United States recommended by the Interagency Advisory

Committee on Water Data (1982). It has subsequently been adopted in all flood frequency

studies in the United States including those highlighted in Table 4 in Section 2.4.2. Similarly,

Generalized Extreme Value is the recommended probability distribution in the United Kingdom

(Chow and Watt, 1992). Chow and Watt (1992) argue that there may be more than one

distribution which fits the data. Thus, recommendation of a single distribution for a large

geographical region may not be desirable.

Chow and Watt (1992) recommend the Akaike Information Criterion (AIC) to select the best

probability distribution amongst a set of candidate distributions. AIC gives a model selection

criterion based on the combination of model fit, determined by the log likelihood term in

Equation (26), and the number of parameters (k) of the model determined by the second term in

Equation (26). A combination of these two terms would result in a unique value. According to

the Akaike model selection procedure the model with a minimum AIC value best describes the

sample data set and should be selected. So, choosing a distribution with more number of

parameters is not held by this selection criterion because there is an additional uncertainty

associated with parameter estimation, which increases as the number of parameters increase. The

improved fit and the number of parameters should compensate each other thereby resulting in a

minimum AIC value, as can be observed from Equation (26). Goodness-of-fit tests such as the

Kolmogorov-Smirnov or Chi-Square tests could not be adopted as these methods have a

tendency to select a distribution with more number of parameters, which essentially means a

better fit. However, the uncertainty inherent with these additional parameters is not reflected

during distribution selection by goodness-of-fit tests. This situation ultimately creates a false-

sense of certainty and confidence when applied to real-life design applications. AIC has also

been previously applied to the context of Northern Ontario in the study by Watt (1994) which

resulted in minimizing the relative standard errors of the RFFA equations when compared to the

results obtained by previous studies. Thus, considering all the above mentioned factors

distribution selection using AIC was identified as the best approach that can also be extended to

the current study.

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AIC = −2 log(𝐿) + 2k Equation (26)

Burnham and Anderson (2004) identified a limitation in existing model selection literature when

AIC value is used for small sample sizes (defined by n/k < 40; where n is the sample size and k

is the number of parameters). Using Equation (26) researchers have concluded that for small

sample sizes AIC sometimes over fits the data (Burnham and Anderson, 2004). Overfitting

implies that the statistical model has random errors and the model is not a true representation of

the underlying condition. For finite and small sample sizes a second order criterion as proposed

by Burnham and Anderson (2004). The data series generally available for flood frequency

studies are relatively small so a second order criterion, like in Equation (27) is applied.

AIC = −2 log(𝐿) + 2k + 2𝑘(𝑘 + 1)

𝑛 − 𝑘 − 1 Equation (27)

Where k = number of parameters; L = maximized value of the likelihood function; n = sample

size.

For large sample sizes Equation (27) converges to Equation (26). However, for the purpose of

the current study, Equation (27) is used to estimate the AIC for each candidate distribution.

Statistical software’s can be used to estimate the value of the likelihood function and also the

associated station flood quantiles (2 year, 10 year, 25 year, 50 year and 100 year). These

software’s use different fitting methods like the method of moments, method of maximum

likelihood, L-moments etc. A distribution fitting software, Easyfit, with its excel add-in, utilizes

the least computationally intensive method for estimation of underlying distribution and the

distribution parameters. The methods used for parameter estimation for the different candidate

distributions are available in its software documentation. A comparison study for two

representative stations was also carried out in ‘R project’, an open source programming language

for statistical computation, which presented identical results of AIC values.

Alberta Transportation (2001) argues that the selection of an appropriate probability distribution

is more important than the differences caused by various fitting methods (like method of

moments, method of maximum likelihood, for example) for prediction of flood quantiles.

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Chow and Watt (1992) recommended the used of AIC as a distribution selection criterion.

However, it may also be observed from Table 3 of Chow and Watt (1992) that for the 42 stations

used in the study, the difference in the AIC for the best and second best distribution is very

small. For instances when the difference in AIC values is small, Burnham and Anderson (2004)

recommends a range of difference in AIC values between the model with the lowest AIC and

other candidate distribution models when a particular model cannot be accepted with certainty.

For such models, Burnham and Anderson (2004) recommended calculation of Akaike weights as

in Equation (28) and averaging of the estimates from each candidate model based on these

weights.

𝑤𝑖 =exp (−

∆𝑖

2 )

∑ exp (−∆𝑟

2 )𝑁

𝑟=1

∆𝑖 = AIC𝑖 – AIC𝑚𝑖𝑛 Equation (28)

where i = the model in consideration; wi represents the model weight;

N = the total number of models in consideration for calculation of weights;

AICmin = AIC value of the best fit distribution.

Thus, appropriate weights may be applied to the quantile estimates of the candidate distributions

to compute the station quantiles.

2.6.3 Multiple Regression

The use of multiple regression procedures to develop prediction models for peak flood flows has

increased in the last few decades due to the increased availability of statistical packages (like

SPSS, SAS) capable of processing large datasets. Statistical packages broadly use three

regression procedures which are adopted based on the research goals. These procedures have

different types of controls for entry of a variable in the regression equation. For example the

simultaneous entry (forced entry) procedure is used mainly for exploratory purposes

(Field, 2009). This method gives the control of variable selection to the researcher and may be

used when a given theoretical model is under consideration. Thus, it allows assessment of impact

of each independent variable (Field, 2009). On the other hand, stepwise regression procedure

gives this control of variable selection to the computer which, based on standard algorithms,

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chooses the independent variables. It maximizes the coefficient of determination (R2) and

minimizes the number of predictors at the same time (Field, 2009). Thus, all independent

variables may not be a part of the final regression equation and the most significant variables are

chosen. The third procedure, called hierarchical regression, is generally used for testing

theoretical models of a researcher. The variable entry order is decided by the researcher and is

based on a theoretical justification (Field, 2009).

During the stepwise regression process, a variable is added and is retained at a particular

significance level (generally 5-percent significance for regression analysis). This variable may be

removed when a variable added in a subsequent step has higher significance (Field, 2009).

Stepwise linear regression procedures in SPSS also help in identifying multi-collinearity through

its collinearity diagnostics (Field, 2009). During regression analysis, the results of the

collinearity diagnostics are adopted by SPSS and the corresponding variable demonstrating

multi-collinearity is automatically dropped.

The stepwise regression procedure identifies a relation between the dependent variable (i.e. the

T-year quantile in the current study) and the predictor variables (i.e. climate and physiographic

parameters).The variables that are required for regression analysis with respect to flood

frequency studies can be classified as follows:

1. Response variables: Response variables are those which are measured and are also called the

dependent variables. Thus, the flood quantiles in flood frequency studies may be treated as

the response variables. Each of the variables should be separately tested with all the

predictor variables.

2. Predictor variables: Predictor variables are the independent variables used for development

of a regression equation with the dependent variables. These variables affect the response.

The physiographic and climatic variables in flood frequency studies may be considered as

the predictor variables.

2.6.3.1 Assumptions in Multiple Regression

Predictor variables used in a RFFA study should not be correlated with other predictor variables.

A condition when the predictor variables are related to each other is also referred as multi-

collinearity, which can be identified from the values of correlation coefficients. Parameters that

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are highly correlated have the correlation coefficient close to 1 or -1 in their correlation matrix.

The highly correlated parameters need to be removed from the study unless there is an

appropriate rationale against the removal of variables. RFFA studies (Joy and Whiteley (1996),

Watt (1994), Karuks (1961)) have concluded that drainage area is the most important parameter

for determining peak flow. Thus, predictor variables correlated with the drainage area would

essentially convey the same information about peak flow and thus cannot be treated as its

independent determinant (Watt,1994). Previous studies on flood frequency analysis

(Watt (1994); Rollings (1999)) have also highlighted the importance of the effect of lakes in

decreasing the peak flows and a factor to represent this effect was adopted.

Another important assumption of multiple regression is the condition of normality for both the

response and predictor variables. It is essential to ascertain this assumption before proceeding

with the regression analysis. The assumption for normality can be tested by confirming if the

ratio of skewness and standard error (S.E.) is less than 1.96 or by visual examination of the

histograms before and after transformation. Generally, the annual maximum flow data is highly

right skewed (Chin, 2013). Thus, to perform a regression analysis the data is commonly log

transformed. Log transformations to base 10 have previously been applied to regression analysis

(GREHYS, 1996; Grover et al., 2002; Moin and Shaw, 1986). Logarithmic transformations,

when applied on all the dependent variables and predictor variables, help to linearize the

assumed power equation and to achieve equal variance (normality) required for linear regression.

Thus, a general form of the power function, Equation (29), is assumed which on log-

transformation took the form Equation (30), to be used as the linear regression model.

𝑄 = 𝐾𝑅 ∗ 𝐴𝑎 ∗ 𝐵𝑏 ∗ 𝐶𝑐 …. Equation (29)

𝑙𝑜𝑔𝑄 = 𝑙𝑜𝑔𝐾𝑅 + 𝑎 ∗ 𝑙𝑜𝑔𝐴 + 𝑏 ∗ 𝑙𝑜𝑔𝐵 + 𝑐 ∗ 𝑙𝑜𝑔𝐶 …. Equation (30)

where Q represents the dependent variable; A, B and C represent independent variables; KR, a, b

and c are constants.

2.7 Summary

The detailed review of the hydrology aspects of flood frequency analysis was conducted in the

above chapter with emphasis on the physiography and climate of Ontario. The chapter reviewed

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statistical methods and the recent RFFA studies. Drainage area is the most important contributing

factor when predicting peak flows and urbanization causes changes the flow regime in

catchments. The climate in general and more specifically precipitation is the important flood

causing mechanism. Non parametric screening to assess independence, stationarity, randomness

and homogeneity of flow data has not been investigated in most of the studies from the United

States. But few Canadian studies have adopted non-parametric testing to assess the quality of

streamflow data. This is important considering the temporal changes in drainage catchments and

verifying the statistical assumptions before applying statistical methods. Different statistical

methods have been identified in this section and the availability of statistical packages has

caused a shift towards regression based RFFA equations. The chapter establishes the foundation

for the methodology used in Chapter 3.

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Chapter 3 Methodology

The subsequent sections outline the thesis methodology. The study area for the project, i.e. the

province of Ontario, is divided into ecozones. Flow data were obtained for the gauged stations

across the province. The physiographic parameters were obtained from the Ontario Flow

Assessment Tool (OFAT) III and the precipitation data were obtained from Environment Canada

weather stations. Subsequently, a regression based regional flood frequency analysis is

performed.

3.1 Data Collection

Historical stream flow data were obtained from Environment Canada’s archived Hydrometric

Data Portal. The data from the gauging stations, referred to as HYDAT stations, is collected by

Water Survey of Canada (WSC). Amongst these stations, 17 stations were selected from the

Reference Hydrometric Basin Network (RHBN). Inclusion of these stations was prioritized

because they are likely to remain active in the future and are available for long term monitoring.

For a given HYDAT station the Hydrometric Data Portal provides AMI flow, AMAD flow and

overall average daily flow for all operational years. The overall average daily flow data were

used while synthesizing AMI flow data following procedures outlined by Sangal (1981) when

there were gaps in the historical records. While compiling hydrometric data from WSC a

station’s latitude, longitude and the gross drainage area of the gauge stations was also collected.

Historical stream flow datasets were downloaded for all 271 HYDAT stations in Ontario that

have been operating for over 15 years (Figure 5). Flow data collected by WSC up to and

including December 31st, 2014 were considered for this analysis. All of the 271 stations represent

natural flow conditions and regulated stations were excluded in this study. Regulation affects the

natural flow data and stream flow series, if used, are not reflective of the true hydrologic

conditions of the catchment. It was noted that the actual station record length available was

occasionally shorter than the stations operational length (15 years selected as the threshold). In

all cases the AMI series were shorter than AMAD series. An example of the annual maximum

series for a representative station is provided in Appendix A. The complete dataset for 271

stations used for the analysis (AMAD, AMI and the daily flows) is not reproduced in the thesis

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and is available from the Hydrometric data portal of WSC. A summary of the record data for all

HYDAT stations used in this study is provided in Appendix B.

Figure 5: Location of HYDAT Stations

Physiographic data (i.e. watershed characteristic and land cover) associated with each HYDAT

station were obtained from the Ministry of Natural Resources and Forestry (MNR)’s web-based

Ontario Flow Assessment Tool (OFAT) III utilizing latitude and longitude information collected

from the WSC portal. An example of the data obtained from OFAT is provided in Table 5.

Mean annual precipitation data was collected from the Climate Normals published by

Environment Canada for all 151 weather stations across Ontario from 1981-2010. An isohyetal

map was prepared in ARCMap 10.2 using the Empirical Bayesian Kriging (EBK). The isohyet

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map is shown previously in Figure 2 and was used to determine the interpolated precipitation

values at the individual HYDAT stations.

Table 5: Example of Data from OFAT (Representative Station: 05PB018)

Parameter OFAT representation Value

Station ID 05PB018

Area (km2) Area Km 345.95

Shape Factor ShapFactr 34.61

Mean Elevation (m) MeanElevM 449.7

Maximum Elevation (m) MaxElevM 521.9

Mean Slope (%) MeanSlpPc 5.068

Length of the Main Channel (km) LeOMChKm 109.432

Maximum Channel Elevation (m) MaxChElvM 505.58

Minimum Channel Elevation (m) MinChElvM 400.93

Channel slope (m/km) ChSlp_M_Km 0.96

Channel Slope (%) ChSlp_Pcnt 0.096

Total Area of Water storage (km2) WatrAreaKm 72.07

Area of lakes and open water (km2) OpWAreaKm 54.89

Area of Wetlands (sqkm) WetlAreaKm 17.18

3.2 Data Preparation and Screening

3.2.1 Estimating Annual Maximum Instantaneous (AMI) values for gaps in historical records

Sangal (1981)’s procedure, outlined in Section 2.5.1.1, was used to estimate the gaps in the

historical AMI flow series. Appendix B summarizes the number of years that required AMI

values to be estimated. The procedure used for prediction of K is illustrated in the form of a

flowchart in Figure 6. The estimation of AMI values for a representative station is tabulated in

Appendix C. The procedure was repeated to predict the AMI data for all the station years for the

271 stations selected for the study. After prediction of AMI flow values HYDAT stations with

more than 15 years of data were retained for further analysis.

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Figure 6: Estimation of Missing Values of Instantaneous Peak (Sangal (1981))

3.2.2 Screening of HYDAT stations

The land cover information extracted from OFAT was used to identify and exclude HYDAT

stations that contained more than 20% impervious cover. The value of 20% was determined as

suitable based on various studies, such as Center for Watershed Protection (2003), which suggest

that the hydrology of watersheds within the range of 10-25% impervious cover are impacted by

urbanization. These watersheds exhibit significant differences with respect to both quality and

quantity of runoff. Ten such stations were subsequently separated from the current analysis.

Eight of these ten stations were located in the Mixed Wood region in southern Ontario. Figure 7

shows the location of the urban watersheds in Ontario. Figure 8 shows an urban watershed

delineated by OFAT.

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Figure 7: Location of Urban catchments

Figure 8: Delineation of an Urban Watershed with OFAT

02GH011

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Additionally, information regarding seven stations could not be extracted as OFAT did not

recognize the latitude and longitude reported by WSC as valid points on the stream. The lack of

basin parameters required for the study necessitated the removal of these stations.

A limitation that was identified during data extraction was that OFAT only includes digital

elevation data that is within the provincial boundaries of Ontario. Parts of a watershed extending

outside of the province are not reported by OFAT. Thus, discrepancies were observed in the

drainage area reported by WSC and obtained through delineation by OFAT, for example, WSC

station 05PC018 (latitude: 48.6344, longitude:-93.9133), shown in Figure 9. OFAT delineates

the boundary through lakes and streams along the Ontario provincial boundary excluding the

contributing watershed area within the adjacent State of Minnesota. This led to gross mismatch

in the areas reported by OFAT and WSC for stations with cross-border watersheds.

For a few other stations, which were not along the provincial border, the root cause of

discrepancies between reported OFAT and WSC drainage areas could not be identified.

Discrepancies with respect to WSC data and observed data have also been highlighted in Joy and

Whiteley (1994). The stations with differences greater than 15% in reported watershed area from

WSC and delineated by OFAT were excluded from analysis. The uncertainty in ascertaining the

correct area and the associated data (e.g. channel length, slope, area of lakes and reservoirs)

forced the removal of these stations. Forty-one such stations were identified and removed.

Two stations with drainage areas less than 1 km2 were removed from the Boreal Shield ecozone

as the station quantiles (calculated in the Section 3.3.2) and the area occupied by lakes and

wetlands for these stations were approximately zero. For the current dataset, there were stations

with very large drainage area (largest drainage area = 13,559.5 km2). These stations had a

drainage area that was more than 5 times the mean of the drainage areas used in this study and

were identified as outliers. Thus, five more stations in the Boreal Shield with extremely large

drainage areas (> 5000 km2) were removed.

The Hudson Plain ecozone is a very remote region of Ontario and MTO does not currently

operate any provincial highways this far north. Only three HYDAT stations remained in this

ecozone after the initial data screening (shown in Figure 10) which was insufficient to support

regression analysis. Hence, subsequent analysis presented was limited to two regions: the Boreal

Shield and the Mixed Wood Plains.

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Figure 9: Watershed Delineation Discrepancy in OFAT

Figure 10: Stations in the Hudson Plain

Drainage area

Provincial boundary

Drainage boundary

HYDAT station (05PC018)

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3.3 Data Analysis

New RFFA equations for Ontario were developed following data screening. The analysis

procedure can be understood in three stages as detailed in Chapter 2. Here, each stage depends

on the result obtained at the previous stage.

1. Non parametric testing

2. Station frequency analysis

3. Multiple regression of quantiles

3.3.1 Non-parametric Testing

The first step in development of RFFA equations was to check conformity of stream flow data

for each HYDAT station with basic statistical assumptions (highlighted in Chapter 2). This

statistical analysis was completed using the package SPSS Statistics 22. Only station data found

to be independent, stationary, homogeneous and random were subsequently considered for

station frequency analysis. Completed statistical tests included:

1. Spearman rank order serial correlation coefficient for independence

2. Spearman rank order correlation coefficient for stationarity

3. Mann-Whitney split sample test for homogeneity

4. Runs test for general randomness

The hypotheses for all statistical tests were accepted at 5% significance level. The summary of

the results of non-parametric tests is provided is Appendix D. For the sake of completeness,

Appendix D includes the urban watersheds and also the stations rejected in previous steps.

Fourteen stations in the Boreal Shield Region and twenty-nine stations in the Mixed Wood Plains

were eliminated due to non-compliance with the hypotheses of non-parametric tests. A map of

the stations, non-compliant with the statistical assumptions, is presented in Figure 11.

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Figure 11: Stations Eliminated (non-compliant with nonparametric test hypotheses)

3.3.2 Station Frequency Analysis

Station frequency analysis was performed for the HYDAT stations meet statistical assumption

necessary for multiple regression at 5% significance level. One hundred and fifty stations (rural

watersheds) were retained for analysis at this stage after the previous screening steps. Different

probability distributions have been recommended for flood frequency studies in studies including

Watt (1994), Watt et al. (1989), Chow and Watt (1992), Rao and Hamed (2000), Cunnane

(1989). Seven theoretical probability distributions were tested during station frequency analysis:

1. Normal

2. Lognormal

3. 3-Parameter Lognormal

4. Gumbel

5. Pearson type 3

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6. Log Pearson type 3

7. Generalized Extreme Value

Akaike Information Criterion (AIC) was used for selection of the best probability distribution

amongst the set of candidate distributions. The model with a minimum AIC value best describes

the sample data set and should be selected. Equation (27) outlined in Section 2.6.2, with the

second order correction for finite datasets was used to compute the AIC value. The analysis was

performed using the excel add-in of the distribution fitting software, Easyfit. The initial results

obtained after AIC analysis indicated a small difference between the AIC values for the 1st and

2nd

best fit distribution. Table 6 summarizes the results for the HYDAT data from Ontario.

Table 6: Summary of the Difference in AIC

Difference in AIC value

(between 1st and 2

nd best distribution)

No. of stations

0-2 126

2-7 20

>7 4

Total 150

The intervals for Table 6 were selected based on recommendations from

Burnham and Anderson (2004). Akaike weights, as in Equation (28) (discussed in Section 2.6.2),

were applied to the computed station quantiles as discussed below. Weighing is considered for

three best distributions (w1, w2 and w3) for each station and the weights are applied to

respective quantile estimates to get the station quantiles.

Thus, based on Equation (28), w1 +w2 +w3 =1

For the five return periods selected for the study (Q2, Q10, Q25, Q50 and Q100) the station

quantile is estimated as below

𝑄𝑇 = 𝑤1 ∗ 𝑄𝑇1 + 𝑤2 ∗ 𝑄𝑇2 + 𝑤3 ∗ 𝑄𝑇3 Equation (31)

where, QT1, QT2 and QT3 = T year quantile estimate for the three best candidate distributions

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An example of the calculations for station frequency analysis, i.e. computation of AIC, AIC

weights and the station flood quantiles is shown in Appendix E.

3.3.3 Multiple Regression Analysis

Multiple Regression analysis was chosen for the development of regional equations for Ontario.

A correlation study (Table 7) was performed to check the degree of correlation between predictor

variables. Analysis of the correlation matrix in Table 7 shows that the parameters like the length

of the main channel is strongly correlated with total drainage area (correlation coefficient of

0.83). Thus, it was removed as an independent predictor variable. The area of lakes and wetlands

was also highly correlated with the drainage area (correlation coefficient = 0.98). As highlighted

in Chapter 2, it was essential to include the area of lakes and wetlands because these water

bodies have an attenuation effect on peak flood flows. For the current investigation, several

transformations were tested and the transformation for the variable representing the area of lakes

and wetlands which was weakly correlated with drainage area (correlation coefficient =0.1) was

adopted as the Lake Attenuation Index (Equation (32) ). Thus, this was used as an independent

predictor variable representing lake storage and its attenuation effect on peak flows.

𝐿𝑎𝑘𝑒 𝐴𝑡𝑡𝑒𝑛𝑎𝑡𝑖𝑜𝑛 𝑖𝑛𝑑𝑒𝑥(𝐿𝐼) = 1 +𝑊𝐴

𝐴 Equation (32)

Table 7: Correlation Matrix of Predictor Variables

A SF L WA P

SF -0.009 - - - -

L 0.838 0.371 -

-

WA 0.921 -0.073 0.687 - -

P -0.347 0.015 -0.321 -0.327 -

CS -0.182 -0.381 -0.369 -0.127 -0.139

Where

A = Total drainage area (km2),

SF = Shape Factor = Length x Length/Area (dimensionless),

L = Length of the Main Channel (km),

WA = Area of lakes and Wetlands (km2),

P = Mean Annual Precipitation (mm),

CS = Channel slope (dimensionless).

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Further analysis of the histograms of the independent and dependent variables lead to the

interference that the dataset was highly right skewed. An example for Q25 quantile (dependent

variable) for the 118 stations used in the analysis is shown in Figure 12. As outlined in Section

2.6.3 and Equation (30) the response and predictor variables were log transformed and multiple

regression was subsequently performed.

Figure 12: Histogram for Q25 Quantile (dependent variable)

Variable transformations were performed as outlined in Chapter 2 and stepwise regression was

subsequently performed. The output of the stepwise regression process for the log transformed

variables is enclosed in Appendix F and results are summarized in the subsequent chapter.

Regression analysis was carried out for forty-three stations in the Boreal Shield Region and

seventy-five stations in the Mixed Wood Plains Region. The 118 stations used for flood

frequency analysis, along with the location of Ontario Highways, are shown in Figure 13. The

stations not included in regression analysis, along with the reason for rejection, have been

summarized in Appendix G.

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Figure 13: Regression Stations and Ontario Highways (Source: Highways, 2014)

3.4 Summary

This chapter presents the methodology undertaken for the development of new regional flood

frequency equations for the province of Ontario. All the data available up to and including Dec

2014 for Ontario, i.e. 271 HYDAT stations were selected. After extension of the data series

through established methods, like Sangal (1981), pre-screening was performed where a minimum

record length for each station was set to be 15 years. Non-parametric testing was performed for

HYDAT stations to verify compliance to statistical assumptions. 41 stations demonstrated non-

compliance and were not a part of the subsequent steps, i.e. station frequency analysis and

multiple regression. Station Frequency Analysis helped to calculate the dependent variables, that

is, the T-year Flood Quantile. Ten HYDAT stations were identified as urban watersheds which

had to be subsequently removed from the analysis due to lack of additional data (w.r.t the

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urbanization pattern, initial land cover information at the start of the flow series, etc.). Issues

were identified during watershed delineation using OFAT where the location of HYDAT stations

from WSC was not recognized in OFAT. There were instances where the watersheds were

limited to the provincial boundary and its contributing parts in neighboring provinces are not

considered. This caused removal of such station as the data was not reliable. A correlation study

between predictors helped to identify variables which showed correlation with the drainage area.

Area of lakes and wetlands was transformed before including in the regression analysis.

Subsequently, multiple regression was performed for development of regional flood frequency

equation for Ontario. The results, referred as the Unified Ontario Flood Method, are presented in

Chapter 4.

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Chapter 4 Results of Regional Flood Frequency Analysis

The subsequent chapter presents the results of the regression analysis and the development of the

Unified Ontario Flood Method (UOFM). Computational procedures for the UOFM are presented.

A Design table (Table 8) in conjunction with Figure 1 and Figure 2, can be used by engineers to

compute the T-year flood Quantile. Table 10 is used for the prediction of the range (i.e. the upper

and lower limit) of the T-year flood Quantile.

4.1 Unified Ontario Flood Method (UOFM)

The result of multiple regression is represented as the power equation of the form Equation (33).

The coefficients for Equation (33) are provided in Table 8, which is the design table for the

application of the UOFM. Table 9 provides the summary of descriptive statistics and the range of

independent predictor variables for each region.

𝐐𝑼𝑶𝑭𝑴 = 𝐊𝑹 ∗ 𝐀𝒂 ∗ 𝐋𝐈𝒃 ∗ 𝐏𝒄 Equation (33)

Where QUOFM = annual flood with a T year return period (m3/s) from the regression analysis

A = drainage area (km2)

LI = lake attenuation index (dimensionless)

P = mean annual precipitation (mm)

KR = 10x (x = value of constant obtained from the output of stepwise regression)

a,b,c = exponents (obtained from the output of regression)

Table 8: Coefficients of the Regression Model and Output Summary

T x a b c Adjusted R2

Standard error

(SE) (log units)

Boreal Shield

2 -10.870 0.839 -4.633 3.583 0.965 0.159

10 -8.583 0.795 -4.522 2.917 0.954 0.174

25 -7.834 0.779 -4.510 2.703 0.947 0.183

50 -7.371 0.769 -4.520 2.572 0.942 0.189

100 -6.967 0.759 -4.541 2.457 0.937 0.195

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T x a b c Adjusted R2

Standard error

(SE) (log units)

Mixed Wood Plains

2 -5.483 0.756 -3.061 1.837 0.824 0.147

10 -4.139 0.734 -3.780 1.491 0.790 0.165

25 -3.680 0.728 -4.017 1.372 0.769 0.177

50 -3.397 0.724 -4.162 1.299 0.752 0.186

100 -3.151 0.721 -4.287 1.236 0.736 0.195

Table 9: Range of Parameters used for Equation Development

Range of parameters used to establish the equations

Minimum Maximum Mean Median Standard deviation

Boreal Shield (No. of stations=43)

Area (km2) 1.80 4416.77 908.36 404.53 1189.88

Water Area (km2) 0.168 892.81 143.24 52.00 205.93

Precipitation (mm) 705 1056 866 848 101

Mixed Wood Plains (No. of stations=75)

Area (km2) 13.16 1230.39 243.00 163.91 241.97

Water Area (km2) 0.02 104.33 18.30 12.56 20.29

Precipitation (mm) 813 1219 965 962 94

The standard error of the estimate obtained from the output of the regression analysis is in log

units. Transformation from log units is undertaken to establish the probable range of flood

quantiles (Table 10) following log over addition/subtraction relations (Moin and Shaw, 1985).

These lower and upper limits are applied to the estimated value from Equation (33).

Upper limit (UL):

UL = log (𝑄𝑈𝑂𝐹𝑀) + SE = log (𝑄𝑈𝑂𝐹𝑀 × 10𝑆𝐸) Equation (34)

Lower limit (LL):

LL = log (𝑄𝑈𝑂𝐹𝑀) − SE = log (𝑄𝑈𝑂𝐹𝑀 ÷ 10𝑆𝐸) Equation (35)

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Where 𝑄𝑈𝑂𝐹𝑀 is the result obtained from regression and SE is the standard error of regression in

log units. Thus, the probable range for the QUOFM can thus be established by the relative standard

error:

Relative upper limit (RUL):

RUL: 𝑄𝑈𝑂𝐹𝑀 𝑋 10𝑆𝐸 − 𝑄𝑈𝑂𝐹𝑀

𝑄𝑈𝑂𝐹𝑀= 10𝑆𝐸 − 1 Equation (36)

Relative lower limit (RLL):

RLL: 𝑄𝑈𝑂𝐹𝑀 −

𝑄𝑈𝑂𝐹𝑀

10𝑆𝐸

𝑄𝑈𝑂𝐹𝑀= 1 −

1

10𝑆𝐸 Equation (37)

Table 10: Range of Quantile Estimates

T Standard error

(log units)

Range of Quantiles

Lower limit Upper limit

Boreal Shield

2 0.159 -31% 44%

10 0.174 -33% 49%

25 0.183 -34% 52%

50 0.189 -35% 55%

100 0.195 -36% 57%

Mixed Wood Plains

2 0.147 -29% 40%

10 0.165 -32% 46%

25 0.177 -33% 50%

50 0.186 -35% 53%

100 0.195 -36% 57%

4.2 Illustration of Calculation Steps

The procedure for calculation of flood quantiles by the Unified Ontario Flood Method (UOFM)

is presented in the following steps. This procedure can be applied to any ungauged stream

location within the two ecozones in Ontario. Ungauged locations which are a part of a regulated

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stream should be analyzed on a catchment level, and not using UOFM, as the flow conditions

downstream of a regulation will not follow a naturalized flow regime. The following example for

HYDAT station 02AE001 illustrates the steps to obtain the flood quantiles by UOFM. This

station, in the Boreal Shield region, is not a part of the regression study. The procedure, as

outlined should be used to predict the T year quantiles at the location of interest.

HYDAT Station: 02AE001

Step 1: Obtain the latitude and longitude of the ungauged location

Latitude: 48°55'33" N; Longitude: 87°41'24" W

Step 2: Identify the region in which the drainage basin is located from the ecozone map of

Ontario (Figure 1)

Step 3: Obtain the physiographic parameters required in the regression equations from OFAT:

Drainage Area: 605.47 km2

Area of Lakes and wetlands: 54.15 km2

Step 4: Obtain the mean annual precipitation for the station from the IsoHyetal map shown in

Figure 2.

Mean Annual Precipitation: 827 mm

Step 5: Using Equation (33) and respective coefficients from Table 8 the regression T year

flood Quantiles, QUOFM, are calculated (summarized below). Use the coefficients of the region

where the station is located based the ecozone identified in Step 2.

Step 6: The standard errors of the regression equation were used to establish the lower and upper

limit of the prediction. The range (lower and upper limit) is provided in Table 10. These

percentages are applied to the quantile estimates from Step 5. The final values for T-year

quantile and the lower and upper limit are summarized below.

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Return Period (years) 2 10 25 50 100

QUOFM (m3/s) 56 94 113 127 139

Lower limit of QUOFM (m3/s) 39 63 74 82 89

Upper limit of QUOFM(m3/s) 80 140 172 197 219

4.3 Summary

The result of the Regional Flood frequency Analysis for Ontario is outlined in Chapter 4, Section

4.1. Section 4.2 presents the methodology for designers for the application of Unified Ontario

Flood Method (UOFM). UOFM aims to provide designers with a tool to predict the T-year flood

quantile for drainage basins where the location of interest lacks stream flow data. The presented

equation and design table (Table 8) are anticipated to be adopted by MTO and replace the MIFM

and NOHM for prediction of design flows at streams and river crossings. The subsequent chapter

discusses the verification and comparison study for the UOFM.

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Chapter 5 Verification and Evaluation

The verification and evaluation of the UOFM was undertaken and the results of the verification

analysis are illustrated in Section 5.1. As MTO may frequently encounter small sized watersheds

(less than the lower limit for the UOFM), a check was performed for a small urban watershed

(Section 5.2). Additional analysis was undertaken to validate the performance of the equation for

medium to large urbanized watersheds (Section 5.3). Subsequently, a comparison of UOFM with

other existing RFFA methods in Ontario was performed.

5.1 Verification of Regression Method: Application to Ontario

For verification of the UOFM, eight stations (Table 11) were tested. Stations 1-3 were not a part

of the regression study, and hence can be considered as better indicators of the accuracy of the

regression method. These stations were not a part of HYDAT dataset from WSC till 2014. Due

to lack of additional data all the other stations were selected from the dataset in Appendix B. The

mean annual precipitation for each station was extracted from the isohyetal map of Ontario

(Figure 2). The comparison between the observed quantiles (QT) and predicted quantiles (QUOFM)

are presented in Table 12 and in Figure 14 (bars indicating probable range for UOFM quantiles).

Table 11: Verification Stations Parameters

S.No. Station

ID Latitude/ Longitude

Region*

Drainage Area (km

2)

Lakes & Wetlands (km

2)

Precipitation (mm)

1 02HL003 44°32'22" N/ 77°22'10" W

BS 424.10 50.39 921

2 02AC002 48°54'15" N/ 88°22'36" W

BS 2599.09 256.09 820

3 02AE001 48°55'33" N/ 87°41'24" W

BS 605.47 54.15 827

4 02BF004 46°30'57" N/ 84°27'54" W

BS 49.75 3.34 923

5 05QD017 49°41'56" N/ 93°42'50" W

BS 2.42 0.01 707

6 02FF007 43°33'4" N/ 81°35'22" W

MWP 462.02 4.90 1071

7 02GA043 43°21'52" N/ 80°37'57" W

MWP 13.16 1.03 962

8 02HK008 44°20'17" N/ 77°28'37" W

MWP 89.29 25.86 923

*BS= Boreal Shield; MWP= Mixed Wood Plains

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Table 12: Application of UOFM to Verification Stations

Return Period (years) 2 10 25 50 100

02H

L003

QT (m3/s) 32 62 78 89 100

QUOFM (m3/s) 54 86 101 113 123

Lower limit of QUOFM (m3/s) 37 57 67 73 78

Upper limit of QUOFM (m3/s) 77 128 154 175 193

02A

C002

QT (m3/s) 103 180 220 249 278

QUOFM (m3/s) 177 281 331 368 398

Lower limit of QUOFM (m3/s) 123 188 217 238 254

Upper limit of QUOFM (m3/s) 255 419 504 569 623

02A

E001 QT (m

3/s) 73 119 132 149 161

QUOFM (m3/s) 56 94 113 127 139

Lower limit of QUOFM (m3/s) 39 63 74 82 89

Upper limit of QUOFM(m3/s) 80 140 172 197 219

02B

F004 QT (m

3/s) 15 26 31 35 39

QUOFM (m3/s) 11 19 24 27 30

Lower limit of QUOFM (m3/s) 8 13 16 18 19

Upper limit of QUOFM (m3/s) 16 29 36 42 47

05Q

D017

QT (m3/s) 0.08 0.23 0.32 0.39 0.46

QUOFM (m3/s) 0.45 1.06 1.44 1.76 2.07

Lower limit of QUOFM (m3/s) 0.31 0.71 0.94 1.13 1.32

Upper limit of QUOFM (m3/s) 0.65 1.58 2.2 2.71 3.25

02F

F007 QT (m

3/s) 150 268 328 373 419

QUOFM (m3/s) 121 208 250 281 313

Lower limit of QUOFM (m3/s) 86 142 167 183 200

Upper limit of QUOFM (m3/s) 170 303 376 432 490

02G

A043

QT (m3/s) 3 4 5 6 6

QUOFM (m3/s) 6 10 12 14 16

Lower limit of QUOFM (m3/s) 4 7 8 9 10

Upper limit of QUOFM (m3/s) 8 15 19 22 25

02H

K008 QT (m

3/s) 7 11 13 14 16

QUOFM (m3/s) 13 20 23 26 28

Lower limit of QUOFM (m3/s) 9 14 15 17 18

Upper limit of QUOFM (m3/s) 18 29 35 39 44

Overestimated UOFM quantiles relative to observed quantiles (QT )

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Figure 14: Observed and Predicted Quantiles for Verification Stations

0

50

100

150

200

250

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02HL003)

QUOFM QT

0

200

400

600

800

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02AC002)

QUOFM QT

0

50

100

150

200

250

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02AE001)

QUOFM QT

0

10

20

30

40

50

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02BF004)

QUOFM QT

0

1

2

3

4

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 05QD017)

QUOFM QT

0

200

400

600

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02FF007)

QUOFM QT

0

10

20

30

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02GA043)

QUOFM QT

0

10

20

30

40

50

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02HK008)

QUOFM QT

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For three of the verification stations the observed flood flows (QT) are not within the probable

range established by the upper and lower limit of the regression relation (shown as bars above

and below QUOFM in Figure 14). Two of these stations (05QD017 and 02GA043) have very small

drainage areas (2.62 km2 and 13.16 km

2, respectively) and therefore it is not surprising that

prediction errors are more significant. Station 02KH008 has a medium sized catchment

(89.29 km2) but observed flood quantiles still fall outside of probable range. In all three cases the

UOFM method overestimated the size of the flood. This produces conservative flood estimates

that will likely be larger than observed flood flows.

5.2 Analysis of the UOFM for a Small Urban Watershed

The UOFM equations are developed for rural catchments and the range of parameters used for

development of equation is outlined in Table 9. However, during subsequent discussions with

MTO it was felt necessary to test the performance of UOFM for small urban catchments,

particularly in the Mixed Wood plains ecozone. Only a single station was identified in the Mixed

Wood plains with an urban watershed that also conformed to the statistical assumptions tested

through nonparametric testing. The parameters and results for this station are highlighted in

Table 13 and Table 14 below. It should be noted UOFM was not developed using the data for

urban catchments. Thus, caution and professional judgement must be considered if applying this

method to an urban setting.

Table 13: Small Catchment Parameters

S.

No.

Station

ID

Latitude/

Longitude Region

*

Drainage

Area (km2)

Lakes &

Wetlands (km2)

Precipitation

(mm)

1 02HB021 43°13'52" N/

79°58'25" W MWP 8.12 0.16 937

*BS= Boreal Shield; MWP= Mixed Wood Plains

Table 14: Small Catchment Flood Quantiles

Return Period(years) 2 10 25 50 100

02H

B021

QT (m3/s) 2 4 6 7 8

QUOFM (m3/s) 4 8 11 12 14

Lower limit of QUOFM (m3/s) 3 6 7 8 9

Upper limit of QUOFM (m3/s) 6 12 16 19 22

Overestimated UOFM quantiles relative to observed quantiles (QT )

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Similar to the verification stations the UOFM produced flood predictions are moderately larger

than observed flood flows. It may be noted that the urban water cycle and urban flow regime can

be drastically different from its pre-development state. Caution and judgement must be exercised

if applying the UOFM to urban catchments. Recommendations for urban flood modelling are

discussed further in Section 5.4.

5.3 Analysis of UOFM for Medium to Large Urban Watersheds

Urbanization poses a challenge of increase in peak flows. The complex interplay of various

components in the urban environment and lack of adequate data for urban Ontario makes it

difficult to perform frequency analysis as for the rural watersheds. However, with changes in

land use such watersheds are frequently encountered by MTO. Thus, it would be imperative to

evaluate the performance of the UOFM equations for medium to large sized urban watersheds.

The urban watersheds tested are summarized in Table 15. The imperviousness (obtained from the

OFAT land cover information) for these watersheds varies from 23% for station 2 below to about

86% for Station 7. It may be noted that the equations are not developed using the data for urban

catchments and so adequate caution must be applied while using them for urban catchments.

Table 15: Medium to Large Urban Catchment Parameters

S.No. Station

ID

Latitude/

Longitude Region

*

Drainage

Area (km2)

Lakes &

Wetlands (km2)

Precipitation

(mm)

1 02DD014 46°18'42" N/

79°26'54" W BS 35.55 3.45 1025

2 02GE005 42°56'2" N/

81°21'4" W MWP 149.83 4.78 1001

3 02HC030 43°36'6" N/

79°33'22" W MWP 216.42 3.50 812

4 02EC009 44°5'41" N/

79°29'22" W MWP 174.73 9.65 855

5 02CF012 46°25'38" N/

81°5'54" W BS 205.28 33.32 898

6 02GH011 42°18'35" N/

82°55'42" W MWP 55.11 0.47 923

7 02HC033 43°38'50" N/

79°31'10" W MWP 68.93 0.56 817

8 02HA023 43°12'1" N/

79°49'13" W MWP 25.73 0.02 899

*BS= Boreal Shield; MWP= Mixed Wood Plains

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Table 16: Analysis Results for Medium to Large Urban Watersheds

Return Period (years) 2 10 25 50 100

02D

D014 QT (m

3/s) 9 15 18 20 22

QUOFM (m3/s) 11 18 21 24 27

Lower limit of QUOFM (m3/s) 7 12 14 16 17

Upper limit of QUOFM (m3/s) 16 27 33 37 42

02G

E005

QT (m3/s) 31 53 65 74 83

QUOFM (m3/s) 43 76 93 105 117

Lower limit of QUOFM (m3/s) 31 52 62 68 75

Upper limit of QUOFM (m3/s) 60 111 139 161 183

02H

C030

QT (m3/s) 87 136 162 180 199

QUOFM (m3/s) 40 77 96 111 126

Lower limit of QUOFM (m3/s) 29 53 64 72 80

Upper limit of QUOFM(m3/s) 57 113 145 170 197

02E

C009

QT (m3/s) 30 54 67 77 87

QUOFM (m3/s) 34 62 76 87 98

Lower limit of QUOFM (m3/s) 24 42 51 57 62

Upper limit of QUOFM (m3/s) 47 90 115 133 153

02C

F012 QT (m

3/s) 24 36 41 45 49

QUOFM (m3/s) 22 38 45 51 56

Lower limit of QUOFM (m3/s) 16 25 30 33 36

Upper limit of QUOFM (m3/s) 32 56 69 79 88

02G

H011 QT (m

3/s) 28 41 44 47 49

QUOFM (m3/s) 19 35 44 50 57

Lower limit of QUOFM (m3/s) 13 24 29 33 36

Upper limit of QUOFM (m3/s) 26 51 66 77 89

02H

C033

QT (m3/s) 34 56 67 75 83

QUOFM (m3/s) 18 35 44 50 57

Lower limit of QUOFM (m3/s) 13 24 29 33 37

Upper limit of QUOFM (m3/s) 25 51 66 77 90

02H

A023

QT (m3/s) 19 25 27 28 29

QUOFM (m3/s) 10 20 25 29 33

Lower limit of QUOFM (m3/s) 7 14 17 19 21

Upper limit of QUOFM (m3/s) 14 29 38 44 51

Overestimated UOFM quantiles relative to observed quantiles (QT )

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Figure 15: Observed and Predicted Quantiles for Medium to Large Urban Watersheds

0

10

20

30

40

50

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02DD014)

QUOFM QT

0

50

100

150

200

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02GE005)

QUOFM QT

0

50

100

150

200

250

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02HC030)

QUOFM QT

0

50

100

150

200

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02EC009)

QUOFM QT

0

20

40

60

80

100

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02CF012)

QUOFM QT

0

20

40

60

80

100

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02GH011)

QUOFM QT

0

20

40

60

80

100

0 20 40 60 80 100Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02HC033)

QUOFM QT

0

20

40

60

0 20 40 60 80 100

Flo

od

Qu

an

tile

(m

3/s

)

Return period, T (years)

Flood Quantiles (Station: 02HA023)

QUOFM QT

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The result of the limited analysis shown graphically in Figure 15 and presented in Table 16 does

not conclusively reflect the performance of the UOFM on medium to large urban watersheds.

Three of the eight watersheds of varied drainage area were over predicted by the UOFM. For

many of the cases, the UOFM under predicted the flood quantiles compared to the observed

values. Thus, appropriate caution and engineering judgement should be applied if using the

UOFM for urban drainage basins.

5.4 Simulation for Peak Flow Estimation: Case of Urban Floods

Evaluation of flood frequency characteristics of urban drainage basins was not possible due to

the limited availability of stream flow data. In situations when the data was available, the record

length was not suitable. Urbanization significantly alters the hydrological cycle by increasing the

volume and speed of runoff. Thus, the runoff characteristics of such a developed state are very

different from its pre development state. Another important feature of urban floods, pointed out

by Watt et al. (1989), is the behavior of urban flood control measures. These features affect the

‘urban response’ to basic hydrologic events. Thus, urban runoff models require detailed analysis

of the urban drainage basin, its connection with the basins flood control infrastructure and

changes in the hydrologic cycle which have resulted because of urbanization-particularly the

effect of abstractions, rainfall and runoff characteristics of the basin.

Simulation based approach also depends on the availability of relevant hydrologic and basin

parameters of the basin. It may be selected depending on the objective of the project and level of

precision required (which is high in case of urban projects due to its effect on life and property).

These involve detailed mathematical simulation of rainfall-runoff models in either 1-D or 2-D

environment. They are helpful in understanding the interaction between rainfall and flooding.

Models like rational method and unit hydrograph are generally used for simpler applications

whereas SWMM, which has a good applicability for detailed analysis, can be used for complex

problems like design of systems and prediction of peak flows (Watt et al. (1989)). Currently,

flood mapping techniques also integrate runoff models with GIS technology and produce

inundation maps which are necessary for planning in an urban environment. Additionally, there

are only few studies which deal with the condition of a surcharged pipe network and flooding on

the catchment surface together (Mark et al. 2004). This condition is a common occurrence in

urban environments which also needs detailed investigation.

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In view of the limited availability of flow data (10 HYDAT stations) and incomplete land cover

information for the starting year of the flow series for the available stations, it was difficult to

assess the stationarity of the HYDAT stations. The lack of information about the urban flood

control measures in the catchments and the complex interaction among various elements in an

urban hydrologic cycle, the enormous cost on life and property in an urban environment

necessitates a detailed analysis on a catchment level for urban drainage basins. In view of the

above consideration, the feasibility of a study for regional flood frequency analysis for urban

catchments could not be established. All urban flood frequency analysis should be done

separately for each drainage basin taking into account all the mentioned considerations along

with the climate and physiography of the basin.

5.5 Comparison with Other RFFA Methods

The results of the regression based UOFM are compared with the flood estimates derived from

currently accepted practices including the MIFM and NOHM. The calculations for MIFM

(Southern and Shield Region) and NOHM are performed as prescribed in Ontario Ministry of

Transportation (1997).

5.5.1 Comparison of UOFM and MIFM (South)

Two stations are selected for comparison of UOFM with MIFM for Southern Region (Table 17).

As shown in Table 18 both the UOFM and MIFM under predicted flood quantiles. The two

methods produce comparable results however for the two stations tested herein; the UOFM

provided a better estimate of the observed floods.

Table 17: Station Parameters for Comparison with MIFM (South)

S.No. Station

ID

Latitude/

Longitude Region

*

Drainage

Area (km2)

Lakes &

Wetlands

(km2)

Precipitation

(mm)

Slope

(%)

1 02GB009 43°5'57" N/

80°29'19" W MWP 89.34 8.52 951 0.15

2 02MB006 44°31'30" N/

75°48'19" W MWP 107.25 24.64 980 0.141

*BS= Boreal Shield; MWP= Mixed Wood Plains

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Table 18: Comparison of UOFM with MIFM (South)

Station

ID

Return

Period

(yrs)

QT QMIFM QUOFM

Lower limit

of QUOFM

(m3/s)

Upper limit

of QUOFM

(m3/s)

Error

MIFM

(%)

Error

UOFM

(%)

02G

B009

2 35 - 22 16 31 - -38

2.33 - 17 - - - - -

10 61 28 38 26 56 -54 -37

25 71 34 47 31 70 -52 -35

50 79 40 52 34 80 -50 -34

100 86 45 59 37 92 -48 -32

02M

B006

2 26 - 19 13 26 - -27

2.33 - 7 - - - - -

10 38 12 30 20 43 -68 -22

25 44 15 35 23 52 -66 -21

50 48 18 38 25 59 -64 -21

100 53 20 42 27 66 -62 -20

5.5.2 Comparison of UOFM and MIFM (Shield)

Four stations are selected for comparison of UOFM with the MIFM for the Shield region (Table

19). MIFM (Shield) and UOFM flood estimates are presented in Table 20. As an engineer, under

prediction of flows is undesirable and may lead to more frequent flooding events than

anticipated. For the limited comparison, in some instances both UOFM and MIFM under predict

flood quantiles. However, the UOFM captures the observed flood within the established range of

the probable lower and upper limit. Additionally, errors associated with the UOFM were

noticeably smaller than the MIFM (Shield) errors.

Table 19: Station Parameters for Comparison with MIFM (Shield)

S.No. Station

ID

Latitude/

Longitude Region

*

Drainage

Area

(km2)

Lakes

(km2)

Wetlands

(km2)

Precipitation

(mm)

1 02KF017 44°58'6" N/

76°57'58" W BS 151.45 11.86 7.76 880

2 02DD015 45°56'57" N/

79°36'24" W BS 101.45 6.25 6.13 1045

3 02CA002 46°15'48" N/

79°23'42" W BS 108.09 5.47 6.68 999

4 02DD013 46°33'46" N/

84°16'54" W BS 68.27 2.07 10.11 1014

*BS= Boreal Shield; MWP= Mixed Wood Plains

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Table 20: Comparison of UOFM with MIFM (Shield)

Station

ID

Return

Period

(yrs)

QT QMIFM QUOFM

Lower limit

of QUOFM

(m3/s)

Upper limit

of QUOFM

(m3/s)

Error

MIFM

(%)

Error

UOFM

(%)

02K

F017

2 13 - 18 13 27 - 42

2.33 - 17 - - - - -

10 22 25 32 21 47 14 45

25 26 30 38 25 59 13 47

50 29 33 44 28 67 14 48

100 33 38 48 31 75 15 47

02D

D015

2 16 - 25 17 36 - 54

2.33 - 14 - - - - -

10 25 21 39 26 59 -16 60

25 28 24 46 30 70 -14 62

50 31 28 51 33 80 -12 64

100 34 31 56 36 88 -9 63

02C

A002

2 28 - 23 16 34 - -18

2.33 - 16 - - - - -

10 49 23 38 25 56 -53 -23

25 60 27 45 29 68 -54 -26

50 68 31 50 32 77 -55 -27

100 77 35 55 35 86 -55 -29

02D

D013

2 13 - 13 9 19 - 0

2.33 - 8 - - - - -

10 20 12 21 14 31 -39 6

25 23 14 25 16 38 -38 8

50 26 16 28 18 43 -37 10

100 28 18 31 20 48 -35 10

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5.5.3 Comparison of UOFM and NOHM

Four stations which are a part of the UOFM study are selected for comparison of UOFM with the

NOHM (Table 21). UOFM and NOHM flood values are summarized in Table 22. In general, for

the tested stations the NOHM produced slightly lower flood quantile values relative to the

UOFM. Overall the UOFM performs better and the station estimates are within the probable

range of the quantile estimates for the selected watersheds.

Table 21: Station Parameters for Comparison with NOHM

S.No. Station

ID

Latitude/

Longitude Region

*

Drainage

Area (km2)

Lakes &

Wetlands (km2)

Precipitation

(mm)

1 02DD013 46°15'48" N/

79°23'42" W BS 68.27 12.18 1014

2 02BF006 47°03'1" N/

84°24'46" W BS 8.00 1.24 947

3 02BF004 46°30'57" N/

84°27'54" W BS 49.75 4.26 923

4 02BF007 47°2'41" N/

84°24'36" W BS 4.99 0.62 947

*BS= Boreal Shield; MWP= Mixed Wood Plains

Table 22: Comparison of UOFM with NOHM

Station

ID

Return

Period

(yrs)

QT QNOHM QUOFM

Lower limit

of QUOFM

(m3/s)

Upper limit

of QUOFM

(m3/s)

Error

NOHM

(%)

Error

UOFM

(%)

02D

D013

2 13 10 13 9 19 -22 0

10 20 15 21 14 31 -22 6

25 23 18 25 16 38 -24 8

50 26 19 28 18 43 -26 10

100 28 20 31 20 48 -28 10

02B

F00

6

2 2 1 2 1 3 -37 -7

10 3 2 3 2 5 -42 4

25 4 2 4 3 7 -45 8

50 4 2 5 3 8 -47 11

100 5 3 6 4 9 -49 13

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Station

ID

Return

Period

(yrs)

QT QNOHM QUOFM

Lower limit

of QUOFM

(m3/s)

Upper limit

of QUOFM

(m3/s)

Error

NOHM

(%)

Error

UOFM

(%) 02B

F004

2 15 11 11 8 16 -28 -27

10 26 18 19 13 29 -29 -25

25 31 22 24 16 36 -31 -24

50 35 24 27 18 42 -32 -23

100 39 26 30 19 47 -34 -23

02B

F007

2 2 1 1 1 2 -42 -12

10 3 1 3 2 4 -47 -5

25 3 2 3 2 5 -51 -4

50 4 2 4 3 6 -54 -4

100 5 2 4 3 7 -57 -5

5.6 Climate Change Considerations

Researchers often associate changes in flood risk as a possible effect of climate change, but there

are very few studies to substantiate the hypothesis of any increase in peak flows due to the

changing climate (IPCC, 2001). In order to complete regression analysis HYDAT stations were

tested for independence, stationarity, homogeneity, and general randomness. Stations which

failed any one of these statistical tests were excluded from the station frequency analysis and

multiple linear regression analysis. As a result the UOFM presented herein inherently assumes

stationary conditions. The future impacts of climate change on Ontario hydrology remain

uncertain. Isolating climatic (i.e. climate change) and anthropogenic (e.g. urbanization, evolving

SWM infrastructure) causes of changes in stream flow regimes is highly contentious. Moreover,

global climate models cannot accurately predict localized changes in peak flow scenarios and

any short duration change may not necessarily translate to long term ‘climate change’.

Nonetheless, the assumption of continuous changes in climate cannot be relinquished. It is

however a gradual phenomenon, which needs published local evidence to be able to extend it to

the probability-based flood frequency studies.

5.7 Summary

The chapter above presents the results of the verification and evaluation of UOFM to ascertain its

applicability to Ontario watersheds. The smallest drainage area of the watershed analyzed in the

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Mixed Woods region was 13.16 km2. The range for the Mixed Wood ecozones could not be

lowered further due to lack of HYDAT stations that fit the station selection criterions. Thus,

using the regression equation for watersheds below this range is not advisable. However, such

watersheds may be frequently encountered by MTO; hence a check was performed for a small

urban watershed with area less than 13.16 km2 (Section 5.2). UOFM was also tested medium to

large urbanized watersheds. A comparison study was conducted to examine the performance of

the equations relative to the peak flow prediction methods currently used in Ontario. The

comparisons of UOFM estimates with observed values (Section 5.1 and Section 5.5) produced

instances of both over prediction in few cases while under prediction in other cases. Such a

situation establishes that the regression model may be free from bias and the model can be

suitably applied. The chapter also discussed the case of urban floods and the implications of

climate change on flow regimes.

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Chapter 6 Conclusions and Recommendations

This thesis presents the development of new regional flood frequency equations for the province

to Ontario, referred to as the Unified Ontario Flood Method (UOFM). Regional equations have

design applications in predicting the peak flows necessary for planning structures on water

courses. Thus, there is a need to keep them updated with the current flow regimes. The sections

below present the most significant conclusions and recommendations from the current study.

6.1 Conclusions

The broad objective of the study was the development of Regional Flood Frequency Analysis

(RFFA) procedures for the province of Ontario. Based on the analysis of currently used methods,

like MIFM and NOHM, some drawbacks were identified and highlighted in Section 1.2. These

drawbacks led to the need of the current study. The important conclusions with respect to these

considerations are discussed.

1. Availability of approximately twenty years of additional stream flow data since the last

study of MIFM and NOHM completed in 1996 and 1994, respectively. The additional

data, when accounted for, will provide a better representation of the current watershed

and stream flow conditions.

The available datasets until Dec 2014 was utilized for the development of the UOFM. The total

number of station analyzed in the province was increased to 271 stations (from 46 in MIFM and

11 in NOHM). As outlined in Section 5.5, the UOFM has shown to provide improved prediction

than the currently used methods, the MIFM and NOHM. UOFM minimized the errors with

respect to the observed station quantiles in comparison to MIFM and NOHM. The range of flood

quantiles, i.e. the upper and lower limit of UOFM, provides additional flexibility to engineers

and designers based on the catchment conditions under consideration. The results of the

verification study tend to provide conservative estimates of peak flows in drainage catchments.

Such a situation may be desirable for engineers and designers given the uncertainty of future

conditions both in terms of extreme weather and increasing urbanization. Overall comparison of

observed values of during the verification and comparison study showed both over prediction by

UOFM in some cases whereas under prediction in other cases. This leads to the conclusion of

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less bias in the regression model. It is not advisable to use the UOFM prediction for drainage

area outside the size range used for its development. At the same time, UOFM may not perform

for urbanized catchments and regulated streams.

2. Changes in catchment characteristics, which lead to gradual changes in the flow

regime, should be taken into consideration.

The catchments characteristics are gradually changing in the province, especially in southern

Ontario which is characterized as the Mixed Wood Plain Ecozone. Changes in catchment

characteristics lead to gradual changes in the flow regime. This needs to be taken into

consideration during the development of RFFA procedures. Thus, the RFFA equations should be

updated every 10 years (Vaill, 2000) and the proposed UOFM should also be updated in due

course.

3. Inconsistency in area classification and the corresponding equation for prediction of

flood quantiles needs to be addressed.

The adoption of one method, i.e. the UOFM will remove the inconsistencies in the area

classification. This is especially relevant for the Shield region where there was uncertainty in the

equation to be used for drainage areas greater than 25 km2, when both the MIFM (Shield) and

NOHM can be applied. It can also be observed from Table 20 and Table 22 for HYDAT station

02DD013, which is tested with both MIFM and NOHM, the flood estimates obtained are slightly

different on comparison of both the methods. Thus, UOFM removes the uncertainty in the

method to be applied for drainage areas in the Shield region.

4. Analysis procedures for urban watersheds, predominately required for the south, are

non-existent. A review of the available data to ascertain the feasibility of such a study

was requested to be performed.

This thesis analyzed the data available for urban catchments. Only 10 urban catchments could be

identified for the whole province (Figure 7). A flood frequency study with 10 catchments was

not practical. Addition data was also provided by the Credit valley conservation (CVC) authority.

The maximum record length of the CVC stream gauging stations was approximately 7 years.

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Thus, in the current scenario, flood frequency analysis for urban Ontario was not considered

feasible. There is a need to start long term monitoring of stream flows in urban catchments.

6.2 Limitations and Recommendations for Future Studies

The objective of the study was to develop a simple and easy to use set of equations for regional

flood frequency analysis (RFFA). Ontario does not have a preset procedure for development of

RFFA equations. Such a situation may be of advantage to a researcher, where she is not fixed in

her ideas and has the freedom to explore. At the same time, not having a defined procedure is a

challenge, because this forces the researcher to difficult decisions based on the copious, and

sometimes conflicting, recommendations available worldwide for development of RFFA

equations. With the variation in climate and physiography, across Canada in general and Ontario

in particular, the lack of defined RFFA procedures presented to opportunity to break with

tradition and use individually selected distributions to fit station data (Section 3.3.2) instead of

imposing a single probabilistic distributions (e.g. Log-Pearson type 3 as has been specified for

the United States or 3-Parameter Lognormal which is widely accepted in Ontario) to all gauge

stations. Implementing more analytically rigorous and computationally complex RFFA

procedures improved the predictive performance of the UOFM. The used of more HYDAT

stations than previous studies helped to minimize the standard errors of regression. Thus, it is

highly recommended that long term stream flow monitoring is crucial and more such stations,

like the RHBN stations should be added in the province.

There is a need for a tool, such as the Consolidated Frequency Analysis Tool from Ministry of

Natural Resources and Forestry (previously available for Ontario but is no longer supported), for

station frequency analysis and computation of station quantiles. RFFA should be conducted at

least every 10 years (Vaill, 2000) to account for changes in the catchment and the flow regimes

and the current UOFM should be subsequently updated. A tool, specifically designed for Flood

Frequency Analysis, will provide an ease when revising the UOFM, instead of using various

statistical software for different computational tasks.

With rapid changes in watershed characteristics it is imperative to acknowledge the variations

which the regression model would bring to flood estimates. Only 10 HYDAT stations from the

271 stations were classified as predominately urban stations (more than 20% of impervious

cover) based on the current land cover data obtained from OFAT. The land cover details for

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these stations at the beginning of their respective flow series were not available to ascertain if the

land cover changed drastically with time. Thus, it is recommended to study the urban floods for

each watershed separately rather than on a regional basis. The considerations and simulation

techniques identified in Section 5.4 may be applied here.

Over the course of this study many limitations of RFFA were encountered. Analysis work is also,

ultimately limited by scope, resources and time. Future investigators may wish to compare the

flood frequency values using regression residuals technique (used in studies like Moin and Shaw

(1985)) to classify homogeneous regions. Comparison of the results obtained from the ecozone

classification may either cause a reclassification of these homogenous regions or provide

legitimacy to the current classification which is based on the ecosystem perspective. At the same

time, ecozones extend to neighboring provinces such as Quebec and Manitoba. Stream flow data

from these regions may be considered if reliable sources of physiographic characteristic can be

obtained. The inclusion of additional data may improve the robustness of the equations.

A challenge during the course of the current investigation was a reliable method for distribution

selection. AIC values led to objective decision making during distribution selection. But, small

difference in AIC values between different candidate distributions posed a challenge of selecting

one distribution over the other. A study considering a distribution selection approach based on

analysis of the skew of the data and the log transformed series as recommended in Alberta

Transportation (2001) may provide more insight into distribution selection. At the same time, it

was also concuded during the course of the current investigation that no ‘one’ distribution can be

universally applied to a province like Ontario with wide variation in climate and physiography.

Finally, additional research needs to address ‘climate change’ scenarios which were not

considered during the course of current investigation. This issue categorically warrants further

investigation. The rejection of approximately 41 stations due to non-compliance with

assumptions of independence, stationarity, homogeneity and randomness indicate the need to

consider changes in the climate and flow regimes. Planned infrastructure and urban growth

should be adaptable to future climate scenarios. Further examining the HYDAT stations for

which the hypothesis of the non-parametric tests was rejected may involve investigating parts of

the data series for conformity with the hypothesis of the non-parametric tests. This may

subsequently alter the number of stations available for regression analysis.

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Hebb, A., & Mortsch, L. (2007). Floods: Mapping Vulnerability in the Upper Thames Watershed

under a Changing Climate. Upper Thames River Conservation Authority.

Insurance Bureau of Canada. (2015). Weather Story. Retrieved 08 01, 2015, from Insurance

bureau of Canada: http://www.ibc.ca/nb/resources/studies/weather-story

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Interagency Advisory Committee on Water Data. (1982). Guidelines for Determining Flood

Flow Frequency: Bulletin 17B of the Hydrology Sub Committee. US Geological Survey.

Retrieved from http://water.usgs.gov/osw/bulletin17b/dl_flow.pdf

IPCC. (2001). Climate Change 2001:Impacts, Adaptation and Vulnerability. Cambridge:

Cambridge University Press.

Joy, D. M., & Whiteley, H. R. (1994). Report on the Evaluation of the Modified Index Flood

Method. Guelph: School of Engineering, University of Guelph.

Joy, D. M., & Whiteley, H. R. (1996). The Modified Index Flood Method Justification of

Recommended Improvements. Guelph: School of Engineering, University of Guelph.

Karuks, E. (1961). Flood Flow Frequency and Studies on Southern Ontario Streams. Department

of Civil Engineering, University of Toronto.

Landers, M. N., & Wilson, K. V. (1991). Flood Characteristics of Mississippi Streams. Jackson,

Mississippi: U.S. Geological Survey Water-Resources Investigations Report 91-4037.

Maclaren Plan Search Inc. (1984). Ottawa River Flood Mapping. Carleton: Regional

Municipality of Ottawa.

Mark, O., Weesaku, S., Apirumanekul, C., Aroonnet, S. B., & Djordjević, S. (2004). Potential

and Limitations of 1D Modelling of Urban Flooding. Urban Hydrology, 299, 284-299.

Mathworks. (2015). Runs Test for Randomness. Retrieved 12 01, 2015, from

http://www.mathworks.com/help/stats/runstest.html?s_tid=gn_loc_drop

Ministry of Natural Resources and Forestry (MNR). (2014). Flood Flow Statistics:For the Great

Lakes- St. Lawrence Watershed System Watershed System. Spatial Data Infrastructure Unit,

Ministry of Natural Resources and Forestry.

MNR. (2015). User Guide for Ontario Flow Assessment Tool (OFAT). Retrieved from

https://www.sse.gov.on.ca/sites/MNR-PublicDocs/EN/CMID/OFAT%20-

%20User%20Guide%20-%20eng.pdf

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Moin, S. M., & Shaw, M. A. (1985). Regional Flood Frequency Analysis of Ontario

Streams:Volume 1 Single Station Analysis and Index Method. Ottawa: Environment Canada.

Moin, S. M., & Shaw, M. A. (1986). Regional Flood Frequency Analysis for Ontario Streams:

Volume 2 Multiple Regression Method. Ottawa: Environment Canada.

Ontario Ministry of Natural Resources. (2012). EcoZone. Peterborough: Ontario Ministry of

Natural Resources.

Ontario Ministry of Transportation. (1997). Drainage Management Manual. Transportation

Engineering Branch, Quality and Standards Division, Drainage and Hydrology Section.

Ontario Ministry of Transportation. (2008). Highway Drainage Design Standards. Ministry of

Transportation.

Ontario Minstry of Transportation. (2015). Bridge repairs. Retrieved 11 18, 2015, from Ontario

Minstry of Transportation: http://www.mto.gov.on.ca/english/highway-bridges/ontario-

bridges.shtml

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Floods in Rural Basins of North Carolina-revised. Raleigh, North Carolina: U.S. Geological

Survey Water Resources Investigation Report 01-4207.

Rao, A. R., & Hamed, K. H. (2000). Flood Frequency Analysis. CRC Press.

Rollings, K. (1999). Regional Flood Frequency Analysis for the Island of Newfoundland. St.

John's, Newfoundland: Department of Environment and Labour, Government of Newfoundland

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Soong, D. T., Ishii, A. L., Sharpe, J. B., & Avery, C. F. (2004). Estimating Flood-Peak

Discharge Magnitudes and Frequencies for Rural Streams in Illinois. U.S. Geological Survey

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ar_onesample_settings_tests_runs.htm

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Waltemeyer, S. D. (2008). Analysis of the Magnitude and Frequency of Peak Discharge and

Maximum Observed Peak Discharge in New Mexico and Surrounding Areas. U.S. Geological

Survey Scientific Investigations Report 2008–5119.

Watt, W. E. (1994). Development of Hydrology Method for Medium-Sized Watersheds in

Northern Ontario. Queens University, Department of Civil Engineering. Kingston: Hydrologic

Modelling Group.

Watt, W. E., Lathem, K. W., & Neill, C. R. (1989). Hydrology of Floods in Canada: A Guide to

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76

Appendix A: Example of the Annual flow data for WSC

Representative station: 02AD010

Annual Maximum Instantaneous Flow:

ID Year TIMEZ

ONE HH:MM MM--DD MAX

02AD010 1971

02AD010 1972

02AD010 1973 EST 1:34 04--26 52.4

02AD010 1974 EST 22:26 05--24 52.1

02AD010 1975 EST 2:03 06--21 56.1

02AD010 1976 EST 5:47 04--24 59.5

02AD010 1977 EST 22:05 04--25 73.3

02AD010 1978 EST 5:45 06--05 39.1

02AD010 1979 EST 4:36 05--15 48.2

02AD010 1980 EST 23:57 05--01 52.4

02AD010 1981 EST 11:36 04--19 24.3

02AD010 1982

02AD010 1983 EST 18:52 05--06 37.7

02AD010 1984 EST 8:04 05--01 47.9

02AD010 1985 EST 19:04 09--28 60.1

02AD010 1986 EST 7:11 05--02 50.2

02AD010 1987 EST 18:18 04--20 21.1

02AD010 1988 EST 23:22 05--06 37.5

02AD010 1989 EST 20:13 05--09 66.5

02AD010 1990 EST 9:19 05--01 66.3

02AD010 1991 EST 16:04 05--04 38

02AD010 1992

02AD010 1993 EST 11:24 05--09 35.3

02AD010 1994 EST 0:36 06--25 36.2

02AD010 1995

02AD010 1996 EST 7:45 05--22 151

02AD010 1997 EST 20:30 05--02 56.9

02AD010 1998 EST 2:00 10--24 43.5

02AD010 1999 EST 23:00 04--24 36

02AD010 2000 EST 16:00 05--12 35.8

02AD010 2001 EST 23:00 05--03 68

02AD010 2002 EST 20:00 04--23 38.2

02AD010 2003 EST 22:00 04--28 39.1

02AD010 2004 EST 21:00 11--02 36

02AD010 2005 EST 9:00 04--20 37.2

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77

ID Year TIMEZ

ONE HH:MM MM--DD MAX

02AD010 2006 EST 2:00 04--22 60.3

02AD010 2007 EST 2:50 06--03 41.1

02AD010 2008 EST 13:15 04--29 61.2

02AD010 2009 EST 4:40 05--04 47.8

02AD010 2010 EST 9:00 10--01 13.7

02AD010 2011 EST 9:35 05--05 47.8

02AD010 2012 EST 5:15 06--02 55.1

02AD010 2013 EST 21:25 05--12 52.6

Annual Maximum Average Daily Flow:

ID Year MM--DD MAX

02AD010 1971

02AD010 1972 05--05 56.1

02AD010 1973 04--25 52.1

02AD010 1974 05--24 52.1

02AD010 1975 06--21 55.5

02AD010 1976 04--23 59.2

02AD010 1977 04--25 72.5

02AD010 1978 06--05 38.5

02AD010 1979 05--15 48.1

02AD010 1980 05--01 52.3

02AD010 1981 04--19 24.2

02AD010 1982 05--05 54.4

02AD010 1983 05--06 37.4

02AD010 1984 05--01 47.7

02AD010 1985 09--28 59.8

02AD010 1986 05--02 50.1

02AD010 1987 04--20 21.1

02AD010 1988 05--07 37.3

02AD010 1989 05--09 65.9

02AD010 1990 05--01 65.9

02AD010 1991 05--04 38

02AD010 1992 05--15 123

02AD010 1993 05--09 35.2

02AD010 1994 06--24 36

02AD010 1995 10--07 40

02AD010 1996 05--22 150

02AD010 1997 05--02 56.4

02AD010 1998 10--24 43

02AD010 1999 04--25 35.9

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78

ID Year MM--DD MAX

02AD010 2000 05--12 35.6

02AD010 2001 05--04 67.5

02AD010 2002 05--16 37.9

02AD010 2003 04--29 38.9

02AD010 2004 11--03 35.9

02AD010 2005 04--17 36.8

02AD010 2006 04--22 60.2

02AD010 2007 06--03 40.9

02AD010 2008 04--29 60.8

02AD010 2009 05--04 47.5

02AD010 2010 10--01 13.7

02AD010 2011 05--05 47.6

02AD010 2012 06--02 54.5

02AD010 2013 05--12 52.1

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79

Appendix B: Summary of all HYDAT Stations

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

1 02HB021 ANCASTER CREEK AT

ANCASTER 28 22 22 0 22

2 04DB001 ASHEWEIG RIVER AT

STRAIGHT LAKE 48 34 41 7 41

3 05PB018 ATIKOKAN RIVER AT

ATIKOKAN 35 22 30 8 30

4 04FB001

ATTAWAPISKAT RIVER

BELOW ATTAWAPISKAT

LAKE

48 18 29 11 29

5 04FC001 ATTAWAPISKAT RIVER

BELOW MUKETEI RIVER 45 23 39 16 39

6 02CB003 AUBINADONG RIVER ABOVE

SESABIC CREEK 34 29 32 3 32

7 05PA012 BASSWOOD RIVER NEAR

WINTON 87 59 83 24 83

8 02BF001 BATCHAWANA RIVER NEAR

BATCHAWANA 47 43 46 3 46

9 02FF007 BAYFIELD RIVER NEAR

VARNA 48 42 45 3 45

10 02LB008 BEAR BROOK NEAR

BOURGET 65 15 49 35 50

11 02GG004 BEAR CREEK ABOVE

WILKESPORT 21 18 20 2 20

12 02GG009 BEAR CREEK BELOW

BRIGDEN 33 28 31 3 31

13 02GG006 BEAR CREEK NEAR PETROLIA 48 43 47 4 47

14 02FC017 BEATTY SAUGEEN RIVER

NEAR HOLSTEIN 29 15 16 1 16

15 02EC011 BEAVERTON RIVER NEAR

BEAVERTON 48 23 33 10 33

16 05RC001 BERENS RIVER ABOVE

BERENS LAKE 33 23 23 0 23

17 02BF004 BIG CARP RIVER NEAR SAULT

STE. MARIE 35 27 32 5 32

18 02GC011 BIG CREEK NEAR KELVIN 51 22 23 1 23

19 02GC010 BIG OTTER CREEK AT

TILLSONBURG 54 47 49 2 49

20 02BB002 BLACK RIVER NEAR

MARATHON 24 21 23 2 23

21 02EC002 BLACK RIVER NEAR

WASHAGO 99 36 98 62 98

22 02AD010 BLACKWATER RIVER AT

BEARDMORE 43 38 42 4 42

23 02JC008 BLANCHE RIVER ABOVE

ENGLEHART 45 38 41 4 42

24 02HE001 BLOOMFIELD CREEK AT 24 22 23 1 23

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80

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

BLOOMFIELD

25 02CG003 BLUE JAY CREEK NEAR

TEHKUMMAH 29 19 21 2 21

26 02FE014 BLYTH BROOK BELOW

BLYTH 30 21 21 0 21

27 02HF004 BOB CREEK NEAR MINDEN 18 13 16 3 16

28 02HD006 BOWMANVILLE CREEK AT

BOWMANVILLE 54 22 41 19 41

29 02FE010 BOYLE DRAIN NEAR

ATWOOD 47 20 22 2 22

30 02ED102 BOYNE RIVER AT EARL

ROWE PARK 47 26 32 6 32

31 04GB005 BRIGHTSAND RIVER AT

MOBERLEY 46 23 24 1 24

32 02HB022 BRONTE CREEK AT CARLISLE 25 23 24 1 24

33 02KF017 BUCKSHOT CREEK NEAR

PLEVNA 21 15 13 0 15

34 02MB010 BUELLS CREEK AT

BROCKVILLE 25 19 16 2 21

35 02GA036 CANAGAGIGUE CREEK NEAR

FLORADALE 15 12 14 2 14

36 02GH003 CANARD RIVER NEAR

LUKERVILLE 38 30 36 7 37

37 02KF011 CARP RIVER NEAR KINBURN 43 29 41 12 41

38 02FC011 CARRICK CREEK NEAR

CARLSRUHE 61 39 50 11 50

39 02LB006 CASTOR RIVER AT RUSSELL 66 22 57 35 57

40 04GA002 CAT RIVER BELOW

WESLEYAN LAKE 44 37 39 2 39

41 02GC030 CATFISH CREEK AT AYLMER 27 19 23 4 23

42 02GC018 CATFISH CREEK NEAR

SPARTA 50 42 49 7 49

43 05QE008 CEDAR RIVER BELOW

WABASKANG LAKE 44 40 43 3 43

44 02DD014 CHIPPEWA CREEK AT NORTH

BAY 40 37 39 2 39

45 02HK007 COLD CREEK AT ORLAND 33 28 31 3 31

46 02HC023 COLD CREEK NEAR BOLTON 52 37 40 3 40

47 02ED007 COLDWATER RIVER AT

COLDWATER 48 41 45 4 45

48 02HM005 COLLINS CREEK NEAR

KINGSTON 45 32 43 11 43

49 02DD015 COMMANDA CREEK NEAR

COMMANDA 40 29 36 7 36

50 02GA017 CONESTOGO RIVER AT

DRAYTON 23 19 22 3 22

51 02DB007 CONISTON CREEK ABOVE

WANAPITEI RIVER 34 25 32 7 32

52 02DB004 CONISTON CREEK NEAR 15 0 8 0 0

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81

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

CONISTON

53 02AB021 CURRENT RIVER AT

STEPSTONE 25 21 22 1 22

54 02GE005 DINGMAN CREEK BELOW

LAMBETH 49 18 40 22 40

55 02GC031 DODD CREEK BELOW

PAYNES MILLS 27 23 25 2 25

56 02DD008 DUCHESNAY RIVER NEAR

NORTH BAY 27 13 26 13 26

57 02HC019 DUFFINS CREEK ABOVE

PICKERING 54 37 46 9 46

58 02HC049 DUFFINS CREEK AT AJAX 25 22 23 1 23

59 02LB012

EAST BRANCH SCOTCH

RIVER NEAR ST. ISIDORE DE

PRESCOTT

25 8 20 14 22

60 02GA035 EAST CANAGAGIGUE CREEK

NEAR FLORADALE 15 12 14 2 14

61 02HC032 EAST HUMBER RIVER AT

KING CREEK 49 34 37 3 37

62 02HC009 EAST HUMBER RIVER NEAR

PINE GROVE 61 42 58 16 58

63 02HB004 EAST SIXTEEN MILE CREEK

NEAR OMAGH 58 43 56 13 56

64 04EA001 EKWAN RIVER BELOW

NORTH WASHAGAMI RIVER 47 15 28 13 28

65 05QA002 ENGLISH RIVER AT

UMFREVILLE 93 34 91 57 91

66 05QA001 ENGLISH RIVER NEAR SIOUX

LOOKOUT 61 14 60 46 60

67 02HC030 ETOBICOKE CREEK BELOW

QUEEN ELIZABETH HIGHWAY 48 42 47 5 47

68 02HC002 ETOBICOKE CREEK NEAR

SUMMERVILLE 18 3 15 12 15

69 02GB007 FAIRCHILD CREEK NEAR

BRANTFORD 50 33 48 15 48

70 04CE002 FAWN RIVER BELOW BIG

TROUT LAKE 26 19 23 4 23

71 02GD010 FISH CREEK NEAR PROSPECT

HILL 69 34 55 21 55

72 02HD012 GANARASKA RIVER ABOVE

DALE 38 26 35 10 36

73 02HD002 GANARASKA RIVER NEAR

DALE 26 14 25 11 25

74 02BF002 GOULAIS RIVER NEAR

SEARCHMONT 47 43 46 3 46

75 02KF015 GRAHAM CREEK AT NEPEAN 27 15 11 0 15

76 02GA041 GRAND RIVER NEAR

DUNDALK 30 15 22 8 23

77 02HB012 GRINDSTONE CREEK NEAR 49 39 47 8 47

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82

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

ALDERSHOT

78 04KA002 HALFWAY CREEK AT

MOOSONEE 22 12 20 8 20

79 02HD013 HARMONY CREEK AT

OSHAWA 34 28 30 3 31

80 02HC013 HIGHLAND CREEK NEAR

WEST HILL 58 35 45 11 46

81 02ED017 HOG CREEK NEAR VICTORIA

HARBOUR 26 17 22 5 22

82 02EC009 HOLLAND RIVER AT

HOLLAND LANDING 49 41 48 7 48

83 02HC025 HUMBER RIVER AT ELDER

MILLS 52 35 45 10 45

84 02HC047 HUMBER RIVER NEAR

PALGRAVE 33 17 22 5 22

85 02GA045 HUNSBURGER CREEK NEAR

HAYSVILLE 16 1 1 0 1

86 02GA046 HUNSBURGER CREEK NEAR

SCHINDELSTEDDLE 16 1 1 0 1

87 02GA043 HUNSBURGER CREEK NEAR

WILMOT CENTRE 21 19 20 1 20

88 02KC014 INDIAN RIVER NEAR

PEMBROKE 17 8 16 8 16

89 02HJ001 JACKSON CREEK AT

PETERBOROUGH 52 38 48 11 49

90 02LA007 JOCK RIVER NEAR

RICHMOND 45 31 43 12 43

91 02CF012 JUNCTION CREEK BELOW

KELLEY LAKE 37 30 35 5 35

92 04JA002 KABINAKAGAMI RIVER AT

HIGHWAY NO. 11 38 19 36 17 36

93 04FA002 KAWINOGANS RIVER NEAR

PICKLE CROW 48 26 28 2 28

94 02GB009 KENNY CREEK NEAR

BURFORD 31 18 28 10 28

95 02GC029 KETTLE CREEK ABOVE ST.

THOMAS 29 26 28 2 28

96 02GC002 KETTLE CREEK AT ST.

THOMAS 69 44 47 3 47

97 04KA001 KWATABOAHEGAN RIVER

NEAR THE MOUTH 46 26 41 15 41

98 05PC016 LA VALLEE RIVER NEAR

DEVLIN 27 12 5 0 12

99 02DD013 LA VASE RIVER AT NORTH

BAY 40 38 38 0 38

100 05PD014 LAKE 114 OUTLET NEAR

KENORA 24 17 5 3 20

101 05QD017 LAKE 223 OUTLET NEAR

KENORA 21 14 6 2 16

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83

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

102 05QD018 LAKE 224 OUTLET NEAR

KENORA 21 14 6 3 17

103 05QD019 LAKE 225 OUTLET NEAR

KENORA 18 15 3 0 15

104 05QD015 LAKE 226 OUTLET NEAR

KENORA 23 17 5 1 18

105 05QD008 LAKE 227 OUTLET NEAR

KENORA 27 18 7 3 21

106 05PD023 LAKE 239 OUTLET NEAR

KENORA 26 20 23 3 23

107 05PD024 LAKE 239, LOWER EAST

INLET, NEAR KENORA 21 12 6 2 14

108 05PD015 LAKE 240 OUTLET NEAR

KENORA 27 20 24 4 24

109 05PD019 LAKE 303 OUTLET NEAR

KENORA 26 21 7 1 22

110 05PD017 LAKE 470 OUTLET NEAR

KENORA 27 19 25 6 25

111 04JF001 LITTLE CURRENT RIVER AT

PERCY LAKE 46 31 32 1 32

112 02HC029 LITTLE DON RIVER AT DON

MILLS 33 25 31 6 31

113 02HC004 LITTLE DON RIVER NEAR

LANSING 21 2 18 16 18

114 02DD020 LITTLE FRENCH RIVER AT

OKIKENDAWT ISLAND 32 0 18 0 0

115 02BA003 LITTLE PIC RIVER NEAR

COLDWELL 42 34 39 5 39

116 02GH011 LITTLE RIVER AT WINDSOR 31 23 25 2 25

117 02HC028 LITTLE ROUGE CREEK NEAR

LOCUST HILL 51 38 48 11 49

118 05QE012 LONG-LEGGED RIVER BELOW

LONG-LEGGED LAKE 34 33 34 1 34

119 02FD002 LUCKNOW RIVER AT

LUCKNOW 35 25 25 0 25

120 02MB006 LYN CREEK NEAR LYN 44 23 34 11 34

121 02HC018 LYNDE CREEK NEAR WHITBY 54 33 47 14 47

122 02MA001 LYNDHURST CREEK AT

LYNDHURST 43 15 15 1 16

123 02ED015 MAD RIVER AT AVENING 26 19 23 4 23

124 02BD003 MAGPIE RIVER NEAR

MICHIPICOTEN 52 34 43 16 50

125 02FE011 MAITLAND RIVER NEAR

HARRISTON 33 24 25 1 25

126 02HG001 MARIPOSA BROOK NEAR

LITTLE BRITAIN 32 15 22 7 22

127 04LK001 MATTAWISHKWIA RIVER AT

HEARST 28 15 16 1 16

128 02GE007 MCGREGOR CREEK NEAR 37 27 29 2 29

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84

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

CHATHAM

129 02AB019 MCVICAR CREEK AT

THUNDER BAY 29 21 23 2 23

130 02FE013 MIDDLE MAITLAND RIVER

ABOVE ETHEL 31 24 24 1 25

131 02FE008 MIDDLE MAITLAND RIVER

NEAR BELGRAVE 47 38 40 2 40

132 02GD004 MIDDLE THAMES RIVER AT

THAMESFORD 76 59 68 9 68

133 02HC033 MIMICO CREEK AT

ISLINGTON 48 45 47 2 47

134 04LJ001 MISSINAIBI RIVER AT

MATTICE 94 51 94 43 94

135 04LM001 MISSINAIBI RIVER BELOW

WABOOSE RIVER 42 28 39 11 39

136 02KF016 MISSISSIPPI RIVER BELOW

MARBLE LAKE 26 26 26 0 26

137 02HL005 MOIRA RIVER NEAR DELORO 49 43 47 5 48

138 02BE001

MONTREAL RIVER AT

ALGOMA CENTRAL AND

HUDSON BAY RAILWAY

21 0 7 0 0

139 02GA042 MOOREFIELD CREEK NEAR

ROTHSAY 25 5 4 0 5

140 02KC015 MUSKRAT RIVER NEAR

PEMBROKE 45 9 14 5 14

141 04GF001 MUSWABIK RIVER AT

OUTLET OF MUSWABIK LAKE 26 11 16 5 16

142 04JC002 NAGAGAMI RIVER AT

HIGHWAY NO. 11 64 41 61 20 61

143 05PA006 NAMAKAN RIVER AT OUTLET

OF LAC LA CROIX 93 51 91 40 91

144 02AB008 NEEBING RIVER NEAR

THUNDER BAY 60 40 55 16 56

145 02GA038 NITH RIVER ABOVE

NITHBURG 42 38 41 3 41

146 02GA018 NITH RIVER AT NEW

HAMBURG 63 53 59 7 60

147 02GA010 NITH RIVER NEAR CANNING 100 51 71 21 72

148 02BF005 NORBERG CREEK (SITE A)

ABOVE BATCHAWANA RIVER 34 30 31 1 31

149 02BF006 NORBERG CREEK (SITE B) AT

OUTLET OF TURKEY LAKE 35 31 32 1 32

150 02BF007

NORBERG CREEK (SITE C) AT

OUTLET OF LITTLE TURKEY

LAKE

33 31 29 0 31

151 02BF008 NORBERG CREEK (SITE D)

BELOW WISHART LAKE 34 29 32 3 32

152 02BF009 NORBERG CREEK (SITE E)

BELOW BATCHAWANA LAKE 33 27 30 3 30

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85

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

153 02BF012

NORBERG CREEK (SITE F) AT

OUTLET OF BATCHAWANA

LAKE

32 29 30 1 30

154 02LB017

NORTH BRANCH SOUTH

NATION RIVER NEAR

HECKSTON

37 11 20 9 20

155 02AB014 NORTH CURRENT RIVER

NEAR THUNDER BAY 42 24 31 7 31

156 04MF001 NORTH FRENCH RIVER NEAR

THE MOUTH 47 31 46 15 46

157 02EA010

NORTH MAGNETAWAN

RIVER ABOVE PICKEREL

LAKE

45 40 44 4 44

158 02EA005 NORTH MAGNETAWAN

RIVER NEAR BURKS FALLS 99 45 98 53 98

159 02ED024 NORTH RIVER AT THE FALLS 26 22 24 2 24

160 05PD022 NORTHWEST TRIBUTARY TO

LAKE 239 NEAR KENORA 26 18 6 2 20

161 02ED026 NOTTAWASAGA RIVER AT

HOCKLEY 25 19 22 3 22

162 02ED101 NOTTAWASAGA RIVER NEAR

ALLISTON 47 20 25 5 25

163 02ED003 NOTTAWASAGA RIVER NEAR

BAXTER 67 38 61 23 61

164 02GF001 O.A.C. FARM GAUGE NO. 2

NEAR MERLIN 17 3 4 1 4

165 02GA032 O.A.C. FARM GAUGE NO. 5 AT

GUELPH 19 15 17 2 17

166 04GB004 OGOKI RIVER ABOVE

WHITECLAY LAKE 43 39 40 1 40

167 02HD008 OSHAWA CREEK AT OSHAWA 55 40 53 13 53

168 02HA024 OSWEGO CREEK AT

CANBORO 26 16 17 2 18

169 04FA001 OTOSKWIN RIVER BELOW

BADESDAWA LAKE 48 27 34 7 34

170 04JD005 PAGWACHUAN RIVER AT

HIGHWAY NO. 11 45 36 44 8 44

171 02FF008 PARKHILL CREEK ABOVE

PARKHILL RESERVOIR 41 35 39 4 39

172 02FF003 PARKHILL CREEK NEAR

PARKHILL 15 43 53 6 49

173 04GA003

PASHKOKOGAN RIVER AT

OUTLET OF PASHKOKOGAN

LAKE

46 6 7 1 7

174 02LB022 PAYNE RIVER NEAR

BERWICK 38 24 30 6 30

175 02EC018 PEFFERLAW BROOK NEAR

UDORA 27 16 25 9 25

176 02EC103 PEFFERLAW BROOK NEAR

UDORA 18 12 15 3 15

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86

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

177 02KA004 PERCH LAKE INLET NO. 1

NEAR CHALK RIVER 22 20 20 0 20

178 02KA005 PERCH LAKE INLET NO. 2

NEAR CHALK RIVER 22 19 19 0 19

179 02KA006 PERCH LAKE INLET NO. 3

NEAR CHALK RIVER 21 18 20 2 20

180 02KA007 PERCH LAKE INLET NO. 4

NEAR CHALK RIVER 21 18 20 2 20

181 02KA008 PERCH LAKE INLET NO. 5

NEAR CHALK RIVER 16 15 16 1 16

182 02KA003 PERCH LAKE OUTLET NEAR

CHALK RIVER 30 28 27 0 28

183 02BB003 PIC RIVER NEAR MARATHON 44 34 43 9 43

184 02AA001 PIGEON RIVER AT MIDDLE

FALLS 79 47 75 28 75

185 05OD032 PINE CREEK NEAR PINE

CREEK 26 20 25 5 25

186 02FD001 PINE RIVER AT LURGAN 40 25 31 6 31

187 02ED014 PINE RIVER NEAR EVERETT 47 32 41 9 41

188 04FA003 PINEIMUTA RIVER AT EYES

LAKE 48 32 42 10 42

189 05PC011 PINEWOOD RIVER NEAR

PINEWOOD 47 31 6 1 32

190 05PB015 PIPESTONE RIVER ABOVE

RAINY LAKE 36 12 15 3 15

191 04DA001 PIPESTONE RIVER AT KARL

LAKE 48 39 42 3 42

192 04MD004 PORCUPINE RIVER AT HOYLE 37 19 24 5 24

193 02BC005 PUKASKWA RIVER AT

PUKASKWA NATIONAL PARK 17 6 8 2 8

194 05PC018 RAINY RIVER AT MANITOU

RAPIDS 83 65 82 17 82

195 02MC027 RAISIN RIVER AT BLACK

RIVER 28 10 8 0 10

196 02MC001 RAISIN RIVER NEAR

WILLIAMSTOWN 54 32 49 17 49

197 02HK008 RAWDON CREEK NEAR WEST

HUNTINGDON 32 22 27 5 27

198 02HA023 REDHILL CREEK AT ALBION

FALLS 15 14 15 1 15

199 02HA014 REDHILL CREEK AT

HAMILTON 37 27 29 2 29

200 02MC026 RIVIERE BEAUDETTE NEAR

GLEN NEVIS 31 21 26 5 26

201 02MC028 RIVIERE DELISLE NEAR

ALEXANDRIA 29 16 21 5 21

202 02FC004 ROCKY SAUGEEN RIVER

NEAR TRAVERSTON 26 0 25 0 0

203 02CA002 ROOT RIVER AT SAULT STE. 43 41 43 0 41

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87

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

MARIE

204 05OD030 ROSEAU RIVER NEAR

CARIBOU 81 45 78 34 79

205 04CA003 ROSEBERRY RIVER ABOVE

ROSEBERRY LAKES 47 30 35 5 35

206 02GH002 RUSCOM RIVER NEAR

RUSCOM STATION 43 37 39 3 40

207 04CD002 SACHIGO RIVER BELOW

OUTLET OF SACHIGO LAKE 23 18 20 2 20

208 02FA004 SAUBLE RIVER AT

ALLENFORD 27 16 19 3 19

209 02FC016 SAUGEEN RIVER ABOVE

DURHAM 38 24 28 5 29

210 02GA037 SCHNEIDER CREEK AT

KITCHENER 22 20 20 0 20

211 02EC010 SCHOMBERG RIVER NEAR

SCHOMBERG 48 33 41 9 42

212 04CC001 SEVERN RIVER AT

LIMESTONE RAPIDS 25 5 22 17 22

213 04CA004 SEVERN RIVER AT OUTLET

OF DEER LAKE 47 14 20 6 20

214 04CA002 SEVERN RIVER AT OUTLET

OF MUSKRAT DAM LAKE 49 27 34 7 34

215 04DC002

SHAMATTAWA RIVER AT

OUTLET OF SHAMATTAWA

LAKE

48 28 38 10 38

216 04JC003 SHEKAK RIVER AT HIGHWAY

NO. 11 38 22 37 15 37

217 02GA044 SILVER SPRING CREEK NEAR

WILMOT CENTRE 16 1 1 0 1

218 02HL004 SKOOTAMATTA RIVER NEAR

ACTINOLITE 59 48 56 8 56

219 02HD007 SOPER CREEK AT

BOWMANVILLE 29 13 24 11 24

220 02LB031

SOUTH BRANCH SOUTH

NATION RIVER NEAR

WINCHESTER SPRINGS

16 3 3 0 3

221 02LB020 SOUTH CASTOR RIVER AT

KENMORE 36 18 26 9 27

222 02FE009 SOUTH MAITLAND RIVER AT

SUMMERHILL 47 42 45 3 45

223 02LB007 SOUTH NATION RIVER AT

SPENCERVILLE 66 44 61 17 61

224 02FF004 SOUTH PARKHILL CREEK

NEAR PARKHILL 59 43 47 4 47

225 02MC030 SOUTH RAISIN RIVER NEAR

CORNWALL 28 9 7 1 10

226 02HB023 SPENCER CREEK AT

HIGHWAY NO. 5 27 25 26 1 26

227 05OD031 SPRAGUE CREEK NEAR 54 49 51 2 51

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88

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

SPRAGUE

228 02BA002 STEEL RIVER NEAR TERRACE

BAY 25 22 24 2 24

229 02FA002 STOKES RIVER NEAR

FERNDALE 38 22 37 15 37

230 02HA022 STONEY CREEK AT STONEY

CREEK 25 16 17 1 17

231 02GH001 STURGEON CREEK NEAR

LEAMINGTON 22 15 18 4 19

232 05QA004 STURGEON RIVER AT

MCDOUGALL MILLS 53 44 51 7 51

233 05QE009 STURGEON RIVER AT

OUTLET OF SALVESEN LAKE 54 47 52 5 52

234 02DC012 STURGEON RIVER AT UPPER

GOOSE FALLS 28 28 28 0 28

235 05PC010 STURGEON RIVER NEAR

BARWICK 35 4 0 0 4

236 02GG003 SYDENHAM RIVER AT

FLORENCE 30 28 29 1 29

237 02GG005 SYDENHAM RIVER AT

STRATHROY 48 36 36 1 37

238 02GG002 SYDENHAM RIVER NEAR

ALVINSTON 67 43 65 22 65

239 02GG007 SYDENHAM RIVER NEAR

DRESDEN 18 15 18 3 18

240 02FB007 SYDENHAM RIVER NEAR

OWEN SOUND 99 42 77 35 77

241 02GD021 THAMES RIVER AT INNERKIP 36 32 35 3 35

242 02GD006 THAMES RIVER NEAR

INGERSOLL 20 2 10 8 10

243 02BF013 TRIBUTARY TO NORBERG

CREEK AT TURKEY LAKE 25 8 22 14 22

244 02GD019 TROUT CREEK NEAR

FAIRVIEW 48 39 40 1 40

245 02GD009 TROUT CREEK NEAR ST.

MARYS 69 38 50 13 51

246 05QC003 TROUTLAKE RIVER ABOVE

BIG FALLS 43 42 43 1 43

247 02GH004 TURKEY CREEK AT WINDSOR 30 29 29 0 29

248 05PB014 TURTLE RIVER NEAR MINE

CENTRE 100 47 95 48 95

249 02HA020 TWENTY MILE CREEK ABOVE

SMITHVILLE 27 22 26 4 26

250 02HA006 TWENTY MILE CREEK AT

BALLS FALLS 57 43 57 14 57

251 02GC021 VENISON CREEK NEAR

WALSINGHAM 48 35 35 0 35

252 02CF011 VERMILION RIVER NEAR VAL

CARON 44 23 30 7 30

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89

S. No. HYDAT

Station ID Station Name

No. of years

Years of

operation

Annual

maximum

Instantaneous

(AMI)

Annual

Maximum

average

daily

(AMAD)

No of

predicted

AMI

values

Total

AMI

years

253 02DD012 VEUVE RIVER NEAR VERNER 41 23 26 3 26

254 02GD020 WAUBUNO CREEK NEAR

DORCHESTER 36 30 33 3 33

255 02HM009

WEST BRANCH LITTLE

CATARAQUI CREEK AT

KINGSTON

25 18 14 0 18

256 02LB018

WEST BRANCH SCOTCH

RIVER NEAR ST. ISIDORE DE

PRESCOTT

35 10 15 8 18

257 02HC038 WEST DUFFINS CREEK

ABOVE GREEN RIVER 40 17 20 4 21

258 02HC031 WEST HUMBER RIVER AT

HIGHWAY NO. 7 49 36 43 7 43

259 02AB017 WHITEFISH RIVER AT

NOLALU 34 30 33 3 33

260 02BA005 WHITESAND RIVER ABOVE

SCHREIBER AT MINOVA MINE 24 22 22 0 22

261 02CF007 WHITSON RIVER AT

CHELMSFORD 54 45 52 7 52

262 02CF008 WHITSON RIVER AT VAL

CARON 54 35 38 3 38

263 02ED009 WILLOW CREEK ABOVE

LITTLE LAKE 23 21 22 1 22

264 02ED010 WILLOW CREEK AT

MIDHURST 26 26 26 0 26

265 02HD009 WILMOT CREEK NEAR

NEWCASTLE 49 37 43 6 43

266 02HM004 WILTON CREEK NEAR

NAPANEE 49 32 46 15 47

267 04CB001 WINDIGO RIVER ABOVE

MUSKRAT DAM LAKE 47 30 33 3 33

268 04DC001

WINISK RIVER BELOW

ASHEWEIG RIVER

TRIBUTARY

48 18 40 22 40

269 02AC001 WOLF RIVER AT HIGHWAY

NO. 17 43 38 39 1 39

270 02GD013 WYE CREEK NEAR

THORNDALE 39 16 19 4 20

271 02KD002 YORK RIVER NEAR

BANCROFT 99 34 85 51 85

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90

Appendix C: Estimation of AMI flow data from AMAD flows

Illustration of the Sangal (1981)’s procedure for a representative station: 02BF002

02BF002

Year

Annual maximum

Instantaneous

(AMI)

Annual Maximum

Average daily

(AMAD) AMI/AMAD Base

factor, K

Date Flow

(m3/s)

Date Flow

(m3/s)

1968

269.95 04--15 238

1969 06--27 337.00 06--27 211 1.60 1.11

1970 06--01 187.00 06--01 182 1.03 1.86

1971 04--21 132.00 04--21 129 1.02 1.69

1972 05--03 180.00 05--03 176 1.02 1.54

1973 04--21 173.00 04--22 153 1.13 1.12

1974 04--30 169.00 04--29 161 1.05 0.97

1975 05--01 235.00 05--01 208 1.13 1.39

1976

254.35 04--19 235

1977

242.18 04--19 224

1978 05--13 114.00 05--13 109 1.05 1.59

1979 04--26 370.00 04--26 353 1.05 1.67

1980 04--10 120.00 04--10 106 1.13 0.90

1981 04--05 222.00 04--05 200 1.11 1.25

1982 05--02 194.00 05--02 182 1.07 0.98

1983 05--03 117.00 05--03 113 1.04 1.52

1984 04--16 135.00 04--16 130 1.04 1.56

1985 04--25 342.00 04--25 321 1.07 1.19

1986 04--20 121.00 04--20 117 1.03 1.41

1987 04--12 52.30 04--12 51.1 1.02 1.45

1988 04--07 203.00 04--07 194 1.05 1.44

1989 04--28 154.00 04--28 146 1.05 1.18

1990 04--26 173.00 04--26 163 1.06 1.09

1991 04--08 139.00 04--08 134 1.04 1.75

1992 04--22 188.00 04--22 179 1.05 1.67

1993 05--04 157.00 05--05 142 1.11 0.78

1994 04--27 214.00 04--27 196 1.09 1.45

1995 10--21 99.40 10--21 86.7 1.15 1.39

1996 05--19 172.00 05--20 165 1.04 1.10

1997 04--29 142.00 04--29 136 1.04 0.40

1998 04--01 171.00 04--01 159 1.08 0.70

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91

02BF002

Year

Annual maximum

Instantaneous

(AMI)

Annual Maximum

Average daily

(AMAD) AMI/AMAD Base

factor, K

Date Flow

(m3/s)

Date Flow

(m3/s)

1999 04--08 169.00 04--08 162 1.04 1.39

2000 03--27 74.40 03--27 73.6 1.01 1.53

2001 10--14 199.00 10--15 157 1.27 0.59

2002 04--18 278.00 04--18 256 1.09 0.93

2003 04--21 186.00 04--21 179 1.04 1.69

2004 04--19 172.00 04--19 163 1.06 1.64

2005 04--11 88.00 04--11 85.9 1.02 1.28

2006 04--14 111.00 04--14 108 1.03 0.67

2007 10--06 75.60 10--20 63.2 1.20 1.20

2008 04--22 244.00 04--23 236 1.03 1.20

2009 04--25 128.00 04--25 123 1.04 1.57

2010 09--24 216.00 09--24 148 1.46 1.05

2011 04--28 115.00 04--28 109 1.06 1.58

2012 03--20 164.00 03--20 158 1.04 1.11

2013 11--18 271.00 05--03 248 1.09 0.67

r= 1.6 K= 1.26

Predicted Value

Page 101: A Unified Ontario Flood Method: Regional Flood Frequency ......performed using multiple regression and the equations for the T-year flood quantile (2, 10, 25, 50 and 100 year) were

92

Appendix D: Summary of results of Non Parametric Analysis

Note:

= Test accepted at 5% significance = Test rejected at 5% significance

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

1 02HB021

2 04DB001

3 05PB018

4 04FB001

5 04FC001

6 02CB003

7 05PA012

8 02BF001

9 02FF007

10 02LB008

11 02GG004

12 02GG009

13 02GG006

14 02FC017

15 02EC011

16 05RC001

17 02BF004

18 02GC011

19 02GC010

20 02BB002

21 02EC002

22 02AD010

23 02JC008

24 02HE001

25 02CG003

26 02FE014

27 02HF004

28 02HD006

29 02FE010

30 02ED102

31 04GB005

32 02HB022

33 02KF017

34 02MB010

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93

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

35 02GA036

36 02GH003

37 02KF011

38 02FC011

39 02LB006

40 04GA002

41 02GC030

42 02GC018

43 05QE008

44 02DD014

45 02HK007

46 02HC023

47 02ED007

48 02HM005

49 02DD015

50 02GA017

51 02DB007

52 02DB004

53 02AB021

54 02GE005

55 02GC031

56 02DD008

57 02HC019

58 02HC049

59 02LB012

60 02GA035

61 02HC032

62 02HC009

63 02HB004

64 04EA001

65 05QA002

66 05QA001

67 02HC030

68 02HC002

69 02GB007

70 04CE002

71 02GD010

72 02HD012

73 02HD002

74 02BF002

Page 103: A Unified Ontario Flood Method: Regional Flood Frequency ......performed using multiple regression and the equations for the T-year flood quantile (2, 10, 25, 50 and 100 year) were

94

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

75 02KF015

76 02GA041

77 02HB012

78 04KA002

79 02HD013

80 02HC013

81 02ED017

82 02EC009

83 02HC025

84 02HC047

85 02GA045

86 02GA046

87 02GA043

88 02KC014

89 02HJ001

90 02LA007

91 02CF012

92 04JA002

93 04FA002

94 02GB009

95 02GC029

96 02GC002

97 04KA001

98 05PC016

99 02DD013

100 05PD014

101 05QD017

102 05QD018

103 05QD019

104 05QD015

105 05QD008

106 05PD023

107 05PD024

108 05PD015

109 05PD019

110 05PD017

111 04JF001

112 02HC029

113 02HC004

114 02DD020

Page 104: A Unified Ontario Flood Method: Regional Flood Frequency ......performed using multiple regression and the equations for the T-year flood quantile (2, 10, 25, 50 and 100 year) were

95

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

115 02BA003

116 02GH011

117 02HC028

118 05QE012

119 02FD002

120 02MB006

121 02HC018

122 02MA001

123 02ED015

124 02BD003

125 02FE011

126 02HG001

127 04LK001

128 02GE007

129 02AB019

130 02FE013

131 02FE008

132 02GD004

133 02HC033

134 04LJ001

135 04LM001

136 02KF016

137 02HL005

138 02BE001

139 02GA042

140 02KC015

141 04GF001

142 04JC002

143 05PA006

144 02AB008

145 02GA038

146 02GA018

147 02GA010

148 02BF005

149 02BF006

150 02BF007

151 02BF008

152 02BF009

153 02BF012

154 02LB017

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96

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

155 02AB014

156 04MF001

157 02EA010

158 02EA005

159 02ED024

160 05PD022

161 02ED026

162 02ED101

163 02ED003

164 02GF001

165 02GA032

166 04GB004

167 02HD008

168 02HA024

169 04FA001

170 04JD005

171 02FF008

172 02FF003

173 04GA003

174 02LB022

175 02EC018

176 02EC103

177 02KA004

178 02KA005

179 02KA006

180 02KA007

181 02KA008

182 02KA003

183 02BB003

184 02AA001

185 05OD032

186 02FD001

187 02ED014

188 04FA003

189 05PC011

190 05PB015

191 04DA001

192 04MD004

193 02BC005

194 05PC018

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97

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

195 02MC027

196 02MC001

197 02HK008

198 02HA023

199 02HA014

200 02MC026

201 02MC028

202 02FC004

203 02CA002

204 05OD030

205 04CA003

206 02GH002

207 04CD002

208 02FA004

209 02FC016

210 02GA037

211 02EC010

212 04CC001

213 04CA004

214 04CA002

215 04DC002

216 04JC003

217 02GA044

218 02HL004

219 02HD007

220 02LB031

221 02LB020

222 02FE009

223 02LB007

224 02FF004

225 02MC030

226 02HB023

227 05OD031

228 02BA002

229 02FA002

230 02HA022

231 02GH001

232 05QA004

233 05QE009

234 02DC012

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98

Station

Number

Station

ID Stationarity Homogeneity Randomness Independence

235 05PC010

236 02GG003

237 02GG005

238 02GG002

239 02GG007

240 02FB007

241 02GD021

242 02GD006

243 02BF013

244 02GD019

245 02GD009

246 05QC003

247 02GH004

248 05PB014

249 02HA020

250 02HA006

251 02GC021

252 02CF011

253 02DD012

254 02GD020

255 02HM009

256 02LB018

257 02HC038

258 02HC031

259 02AB017

260 02BA005

261 02CF007

262 02CF008

263 02ED009

264 02ED010

265 02HD009

266 02HM004

267 04CB001

268 04DC001

269 02AC001

270 02GD013

271 02KD002

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99

Appendix E: Illustration of Station Frequency Analysis

Calculation of AIC:

Representative station: 02FE009 (station no 222 from the summary list in Appendix B)

Station

Name222

Min AIC 462.508 Normal Lognormal Gumbel / EV1Gamma3 /

Pearson III3PLN LP3 GEV

Distribut

ion

Gumbel /

EV1

Normal(43.636;

105.22)

Lognormal(0.40929

; 4.5746)

GumbelMax(34.023;

85.584)

Gamma(5.0275;

18.943; 9.9885)

Lognormal(0.33243;

4.7769; -20.294)

LogPearson3(61.4

; -0.05282; 7.818)

GenExtreme(0.09754;

30.778; 84.191)

Q2 98.054 parameter 1 43.636 0.40929 34.023 5.0275 0.33243 61.4 0.09754

Q10 162.148 parameter 2 105.22 4.5746 85.584 18.943 4.7769 -0.05282 30.778

Q25 194.408 parameter 3 9.9885 -20.294 7.818 84.191

Q50 218.340 k 2 2 2 3 3 3 3

Q100 242.095 AIC 470.82 463.31 462.51 465.42 465.09 465.28 466.28

SIG(LL) -233.267 -229.511 -229.111 -229.416 -229.254 -229.349 -229.849

Data

Count45

loglik

(normal)loglik (lognormal) loglik (gumbel)

loglik

(gamma3)loglik (3PLN) loglik (LP3) loglik (GEV)

1968 202.0 -7.154 -6.940 -6.981 -6.969 -7.001 -6.946 -7.035

1969 93.7 -4.730 -4.569 -4.553 -4.595 -4.561 -4.592 -4.498

1970 99.1 -4.705 -4.623 -4.596 -4.629 -4.600 -4.629 -4.569

1971 62.9 -5.165 -4.727 -4.808 -4.817 -4.811 -4.809 -4.687

1972 81.3 -4.845 -4.517 -4.535 -4.587 -4.549 -4.577 -4.422

1973 71.4 -4.995 -4.574 -4.627 -4.666 -4.638 -4.655 -4.490

1974 87.5 -4.777 -4.529 -4.529 -4.578 -4.540 -4.572 -4.443

1975 179.0 -6.124 -6.334 -6.337 -6.269 -6.326 -6.272 -6.451

1976 128.0 -4.831 -5.107 -5.061 -5.023 -5.040 -5.039 -5.153

1977 158.3 -5.435 -5.807 -5.783 -5.703 -5.757 -5.719 -5.916

1978 98.8 -4.706 -4.620 -4.594 -4.627 -4.598 -4.627 -4.565

1979 89.5 -4.760 -4.539 -4.533 -4.581 -4.544 -4.576 -4.457

1980 90.9 -4.749 -4.548 -4.539 -4.585 -4.548 -4.580 -4.470

1981 181.0 -6.203 -6.386 -6.392 -6.327 -6.383 -6.329 -6.502

1982 152.0 -5.269 -5.652 -5.621 -5.544 -5.594 -5.562 -5.753

1983 41.1 -5.774 -5.942 -5.916 -5.805 -5.903 -5.824 -6.280

1984 97.7 -4.710 -4.608 -4.584 -4.619 -4.588 -4.618 -4.549

1985 115.0 -4.720 -4.857 -4.813 -4.807 -4.802 -4.817 -4.860

1986 105.0 -4.695 -4.698 -4.663 -4.682 -4.661 -4.686 -4.665

1987 72.0 -4.985 -4.567 -4.618 -4.658 -4.630 -4.647 -4.481

1988 75.5 -4.927 -4.537 -4.576 -4.622 -4.588 -4.611 -4.444

1989 35.0 -5.990 -6.682 -6.463 -6.362 -6.473 -6.385 -7.203

1990 85.1 -4.801 -4.520 -4.527 -4.578 -4.540 -4.570 -4.430

1991 80.9 -4.850 -4.517 -4.537 -4.588 -4.550 -4.579 -4.422

1992 93.7 -4.730 -4.569 -4.553 -4.595 -4.561 -4.592 -4.498

1993 93.7 -4.730 -4.569 -4.553 -4.595 -4.561 -4.592 -4.498

1994 70.7 -5.008 -4.583 -4.639 -4.676 -4.649 -4.665 -4.501

1995 81.1 -4.848 -4.517 -4.536 -4.587 -4.549 -4.578 -4.422

1996 137.0 -4.960 -5.302 -5.259 -5.202 -5.234 -5.220 -5.373

1997 228.0 -8.653 -7.636 -7.728 -7.830 -7.795 -7.761 -7.674

1999 70.1 -5.019 -4.590 -4.648 -4.683 -4.658 -4.673 -4.510

2000 103.0 -4.696 -4.671 -4.638 -4.662 -4.639 -4.665 -4.631

2001 102.4 -4.697 -4.664 -4.632 -4.657 -4.633 -4.659 -4.621

2002 79.9 -4.863 -4.519 -4.542 -4.593 -4.555 -4.583 -4.423

2003 85.4 -4.798 -4.521 -4.527 -4.578 -4.539 -4.570 -4.431

2004 140.0 -5.012 -5.369 -5.328 -5.267 -5.302 -5.285 -5.448

2005 114.0 -4.715 -4.840 -4.796 -4.793 -4.786 -4.802 -4.839

2006 86.6 -4.786 -4.525 -4.527 -4.578 -4.539 -4.571 -4.437

2007 75.8 -4.922 -4.535 -4.573 -4.619 -4.585 -4.609 -4.442

2008 197.0 -6.907 -6.808 -6.840 -6.811 -6.851 -6.795 -6.910

2009 164.0 -5.602 -5.949 -5.932 -5.851 -5.909 -5.865 -6.063

2010 71.4 -4.995 -4.574 -4.627 -4.666 -4.638 -4.655 -4.490

2011 115.0 -4.720 -4.857 -4.813 -4.807 -4.802 -4.817 -4.860

2012 34.5 -6.008 -6.756 -6.514 -6.417 -6.527 -6.439 -7.292

2013 109.0 -4.699 -4.758 -4.718 -4.727 -4.713 -4.733 -4.739

Parameters

3

1

2

3

4 3

2

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Illustration of the sections (marked in red above):

Section 1: Illustrates the data for the station.

Section 2: Presents the log likelihood calculation for the station data. The top row presents the summation of the log likelihood for each of

the distributions.

Section 3: Provides the parameters of each of the distribution as obtained from easy fit and the AIC value.

Section 4: Provides the summary of the best fit distribution and the associated quantiles.

Normal Lognormal Gumbel / EV1Gamma3 /

Pearson III3PLN LP3 GEV

Normal(43.636;

105.22)

Lognormal(0.40929

; 4.5746)

GumbelMax(34.023;

85.584)

Gamma(5.0275;

18.943; 9.9885)

Lognormal(0.33243;

4.7769; -20.294)

LogPearson3(61.4

; -0.05282; 7.818)

GenExtreme(0.09754;

30.778; 84.191)

parameter 1 43.636 0.40929 34.023 5.0275 0.33243 61.4 0.09754

parameter 2 105.22 4.5746 85.584 18.943 4.7769 -0.05282 30.778

parameter 3 9.9885 -20.294 7.818 84.191

k 2 2 2 3 3 3 3

AIC 470.82 463.31 462.51 465.42 465.09 465.28 466.28

SIG(LL) -233.267 -229.511 -229.111 -229.416 -229.254 -229.349 -229.849

Parameters

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AIC values for all candidate distributions:

Below is the summary of the AIC value of all the candidate distributions and the difference of the candidate distribution with the model

with lowest AIC.

Calculation of AIC weights and the station flood quantiles:

Min AIC 462.51 463.31 465.09 465.28 465.42 466.28 470.82

Delta AIC 0.00 0.80 2.59 2.78 2.91 3.78 8.31

Distribution Gumbel / EV1 Lognormal 3PLN LP3 Gamma3 / Pearson III GEV Normal

STATI

ON #AIC

Delta

AIC

exp(-

deltaA

IC/2)

Q2 Q10 Q25 Q50 Q100 AICDelta

AIC

exp(-

deltaA

IC/2)

Q2 Q10 Q25 Q50 Q100 AICDelta

AIC

exp(-

deltaA

IC/2)

Q2 Q10 Q25 Q50 Q100 W1 W2 W3 Q2 Q10 Q25 Q50 Q100

222 462.51 0 1 98.05 162.15 194.41 218.34 242.09 463.31 0.8 0.67 96.99 163.88 198.57 224.79 251.33 465.09 2.59 0.27 98.44 161.51 192.19 214.72 237.01 0.51 0.34 0.14 97.74 162.65 195.53 220.05 244.56

Gumbel / EV1 Lognormal 3PLN AIC weights Station flood quantiles

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Appendix F: Stepwise regression output from SPSS

Regression Results

(Note:

1. Only the final output is shown in the part.

2. SI1 in the regression output denotes the transformation of lake attenuation index

3. The output below is the results after the log transformation was applied on the variables.)

Region = Boreal Shield

Descriptive Statisticsa

Mean Std. Deviation N

logQ100 1.7734 .77999 43

logAreaKm 2.3566 .99527 43

logMAP 2.9348 .05119 43

logSI1 .0575 .02563 43

logShapFactr 1.1180 .25951 43

logChSlpDmls -2.5392 .57989 43

a. Region = Boreal Shield

Correlationsa

logQ100 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ100 1.000 .938 .140 -.069 .724 -.815

logAreaKm .938 1.000 -.069 .134 .710 -.941

logMAP .140 -.069 1.000 -.309 .200 .224

logSI1 -.069 .134 -.309 1.000 -.053 -.311

logShapFactr .724 .710 .200 -.053 1.000 -.683

logChSlpDmls -.815 -.941 .224 -.311 -.683 1.000

Sig. (1-

tailed)

logQ100 . .000 .185 .330 .000 .000

logAreaKm .000 . .330 .195 .000 .000

logMAP .185 .330 . .022 .100 .074

logSI1 .330 .195 .022 . .369 .021

logShapFactr .000 .000 .100 .369 . .000

logChSlpDmls .000 .000 .074 .021 .000 .

N logQ100 43 43 43 43 43 43

logAreaKm 43 43 43 43 43 43

logMAP 43 43 43 43 43 43

logSI1 43 43 43 43 43 43

logShapFactr 43 43 43 43 43 43

logChSlpDmls 43 43 43 43 43 43

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a. Region = Boreal Shield

Variables Entered/Removeda,b

Model Variables Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Boreal Shield

b. Dependent Variable: logQ100

Model Summarya,e

Model R R Square Adjusted R Square

Std. Error of the

Estimate Durbin-Watson

1 .938b .879 .876 .27430

2 .960c .922 .918 .22380

3 .970d .941 .937 .19587 2.287

a. Region = Boreal Shield

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logMAP

d. Predictors: (Constant), logAreaKm, logMAP, logSI1

e. Dependent Variable: logQ100

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 22.467 1 22.467 298.612 .000c

Residual 3.085 41 .075

Total 25.552 42

2 Regression 23.548 2 11.774 235.070 .000d

Residual 2.004 40 .050

Total 25.552 42

3 Regression 24.056 3 8.019 209.004 .000e

Residual 1.496 39 .038

Total 25.552 42

a. Region = Boreal Shield

b. Dependent Variable: logQ100

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logMAP

e. Predictors: (Constant), logAreaKm, logMAP, logSI1

Coefficientsa,b

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Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) .042 .109 .383 .704

logAreaKm .735 .043 .938 17.280 .000 .938 .938 .938 1.000 1.000

2 (Constant) -9.206 1.992 -4.621 .000

logAreaKm .746 .035 .952 21.450 .000 .938 .959 .950 .995 1.005

logMAP 3.142 .676 .206 4.646 .000 .140 .592 .206 .995 1.005

3 (Constant) -6.967 1.849 -3.767 .001

logAreaKm .759 .031 .969 24.767 .000 .938 .970 .960 .981 1.019

logMAP 2.457 .621 .161 3.956 .000 .140 .535 .153 .904 1.107

logSI1 -4.541 1.249 -.149 -3.636 .001 -.069 -.503 -.141 .892 1.121

a. Region = Boreal Shield

b. Dependent Variable: logQ100

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .206c 4.646 .000 .592 .995 1.005 .995

logSI1 -.198c -4.341 .000 -.566 .982 1.018 .982

logShapFactr .118c 1.551 .129 .238 .495 2.019 .495

logChSlpDmls .593c 4.473 .000 .577 .114 8.741 .114

2 logSI1 -.149d -3.636 .001 -.503 .892 1.121 .892

logShapFactr .016d .234 .816 .037 .433 2.310 .433

logChSlpDmls .394d 2.891 .006 .420 .089 11.229 .089

3 logShapFactr -.009e -.156 .877 -.025 .427 2.342 .427

logChSlpDmls .215e 1.469 .150 .232 .068 14.727 .068

a. Region = Boreal Shield

b. Dependent Variable: logQ100

c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logMAP

e. Predictors in the Model: (Constant), logAreaKm, logMAP, logSI1

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logMAP logSI1

1 1 1.923 1.000 .04 .04

2 .077 4.992 .96 .96

2 1 2.897 1.000 .00 .02 .00

2 .103 5.310 .00 .98 .00

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3 .000 140.226 1.00 .01 1.00

3 1 3.770 1.000 .00 .01 .00 .01

2 .135 5.275 .00 .42 .00 .64

3 .094 6.334 .00 .57 .00 .25

4 .000 168.762 1.00 .00 1.00 .10

a. Region = Boreal Shield

b. Dependent Variable: logQ100

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value -.1068 2.8216 1.7734 .75681 43

Residual -.46754 .43090 .00000 .18875 43

Std. Predicted Value -2.484 1.385 .000 1.000 43

Std. Residual -2.387 2.200 .000 .964 43

a. Region = Boreal Shield

b. Dependent Variable: logQ100

Charts

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Region = Mixed WoodPlains

Descriptive Statisticsa

Mean Std. Deviation N

logQ100 1.9853 .38037 75

logAreaKm 2.2409 .34956 75

logMAP 2.9826 .04197 75

logSI1 .0390 .03444 75

logShapFactr 1.1352 .20216 75

logChSlpDmls -2.6722 .32149 75

a. Region = Mixed WoodPlains

Correlationsa

logQ100 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ100 1.000 .770 .137 -.560 .194 -.407

logAreaKm .770 1.000 .025 -.268 .340 -.532

logMAP .137 .025 1.000 .041 -.111 -.380

logSI1 -.560 -.268 .041 1.000 -.042 -.008

logShapFactr .194 .340 -.111 -.042 1.000 -.388

logChSlpDmls -.407 -.532 -.380 -.008 -.388 1.000

Sig. (1-tailed) logQ100 . .000 .120 .000 .048 .000

logAreaKm .000 . .414 .010 .001 .000

logMAP .120 .414 . .363 .172 .000

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logSI1 .000 .010 .363 . .360 .472

logShapFactr .048 .001 .172 .360 . .000

logChSlpDmls .000 .000 .000 .472 .000 .

N logQ100 75 75 75 75 75 75

logAreaKm 75 75 75 75 75 75

logMAP 75 75 75 75 75 75

logSI1 75 75 75 75 75 75

logShapFactr 75 75 75 75 75 75

logChSlpDmls 75 75 75 75 75 75

a. Region = Mixed WoodPlains

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter <=

.050, Probability-of-F-to-remove >= .100).

2 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter <=

.050, Probability-of-F-to-remove >= .100).

3 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter <=

.050, Probability-of-F-to-remove >= .100).

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ100

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .770b .593 .587 .24432

2 .853c .728 .720 .20116

3 .864d .746 .736 .19554 1.625

a. Region = Mixed WoodPlains

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logSI1

d. Predictors: (Constant), logAreaKm, logSI1, logMAP

e. Dependent Variable: logQ100

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 6.349 1 6.349 106.359 .000c

Residual 4.357 73 .060

Total 10.706 74

2 Regression 7.793 2 3.896 96.292 .000d

Residual 2.913 72 .040

Total 10.706 74

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3 Regression 7.991 3 2.664 69.667 .000e

Residual 2.715 71 .038

Total 10.706 74

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ100

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logSI1

e. Predictors: (Constant), logAreaKm, logSI1, logMAP

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) .108 .184 .584 .561

logAreaKm .838 .081 .770 10.313 .000 .770 .770 .770 1.000 1.000

2 (Constant) .520 .167 3.122 .003

logAreaKm .727 .069 .668 10.469 .000 .770 .777 .644 .928 1.077

logSI1 -4.210 .705 -.381 -5.974 .000 -.560 -.576 -.367 .928 1.077

3 (Constant) -3.151 1.619 -1.946 .056

logAreaKm .721 .068 .663 10.676 .000 .770 .785 .638 .927 1.079

logSI1 -4.287 .686 -.388 -6.251 .000 -.560 -.596 -.374 .926 1.080

logMAP 1.236 .542 .136 2.279 .026 .137 .261 .136 .997 1.003

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ100

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .118c 1.594 .115 .185 .999 1.001 .999

logSI1 -.381c -5.974 .000 -.576 .928 1.077 .928

logShapFactr -.077c -.968 .337 -.113 .885 1.130 .885

logChSlpDmls .004c .046 .964 .005 .717 1.395 .717

2 logMAP .136d 2.279 .026 .261 .997 1.003 .926

logShapFactr -.056d -.853 .397 -.101 .882 1.134 .820

logChSlpDmls -.079d -1.068 .289 -.126 .692 1.445 .643

3 logShapFactr -.038e -.585 .561 -.070 .867 1.153 .815

logChSlpDmls -.010e -.125 .901 -.015 .563 1.776 .563

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ100

c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logSI1

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109

e. Predictors in the Model: (Constant), logAreaKm, logSI1, logMAP

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logSI1 logMAP

1 1 1.988 1.000 .01 .01

2 .012 12.985 .99 .99

2 1 2.643 1.000 .00 .00 .04

2 .346 2.762 .01 .01 .83

3 .010 15.984 .99 .99 .13

3 1 3.612 1.000 .00 .00 .02 .00

2 .373 3.110 .00 .01 .87 .00

3 .014 16.053 .00 .99 .11 .00

4 9.755E-5 192.433 1.00 .00 .00 1.00

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ100

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value 1.1997 2.6951 1.9853 .32862 75

Residual -.39632 .41307 .00000 .19154 75

Std. Predicted Value -2.391 2.160 .000 1.000 75

Std. Residual -2.027 2.112 .000 .980 75

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ100

Charts

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110

Region = Boreal Shield

Descriptive Statisticsa

Mean Std. Deviation N

logQ50 1.7272 .78809 43

logAreaKm 2.3566 .99527 43

logMAP 2.9348 .05119 43

logSI1 .0575 .02563 43

logShapFactr 1.1180 .25951 43

logChSlpDmls -2.5392 .57989 43

a. Region = Boreal Shield

Correlationsa

logQ50 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ50 1.000 .939 .145 -.068 .727 -.816

logAreaKm .939 1.000 -.069 .134 .710 -.941

logMAP .145 -.069 1.000 -.309 .200 .224

logSI1 -.068 .134 -.309 1.000 -.053 -.311

logShapFactr .727 .710 .200 -.053 1.000 -.683

logChSlpDmls -.816 -.941 .224 -.311 -.683 1.000

Sig. (1-tailed) logQ50 . .000 .176 .332 .000 .000

logAreaKm .000 . .330 .195 .000 .000

logMAP .176 .330 . .022 .100 .074

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logSI1 .332 .195 .022 . .369 .021

logShapFactr .000 .000 .100 .369 . .000

logChSlpDmls .000 .000 .074 .021 .000 .

N logQ50 43 43 43 43 43 43

logAreaKm 43 43 43 43 43 43

logMAP 43 43 43 43 43 43

logSI1 43 43 43 43 43 43

logShapFactr 43 43 43 43 43 43

logChSlpDmls 43 43 43 43 43 43

a. Region = Boreal Shield

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Boreal Shield

b. Dependent Variable: logQ50

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .939b .882 .880 .27345

2 .963c .927 .923 .21834

3 .973d .946 .942 .18977 2.273

a. Region = Boreal Shield

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logMAP

d. Predictors: (Constant), logAreaKm, logMAP, logSI1

e. Dependent Variable: logQ50

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 23.020 1 23.020 307.849 .000c

Residual 3.066 41 .075

Total 26.086 42

2 Regression 24.179 2 12.089 253.589 .000d

Residual 1.907 40 .048

Total 26.086 42

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3 Regression 24.681 3 8.227 228.447 .000e

Residual 1.405 39 .036

Total 26.086 42

a. Region = Boreal Shield

b. Dependent Variable: logQ50

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logMAP

e. Predictors: (Constant), logAreaKm, logMAP, logSI1

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) -.026 .108 -.238 .813

logAreaKm .744 .042 .939 17.546 .000 .939 .939 .939 1.000 1.000

2 (Constant) -9.600 1.944 -4.939 .000

logAreaKm .755 .034 .954 22.263 .000 .939 .962 .952 .995 1.005

logMAP 3.253 .660 .211 4.930 .000 .145 .615 .211 .995 1.005

3 (Constant) -7.371 1.792 -4.114 .000

logAreaKm .769 .030 .971 25.877 .000 .939 .972 .961 .981 1.019

logMAP 2.572 .602 .167 4.273 .000 .145 .565 .159 .904 1.107

logSI1 -4.520 1.210 -.147 -3.735 .001 -.068 -.513 -.139 .892 1.121

a. Region = Boreal Shield

b. Dependent Variable: logQ50

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .211c 4.930 .000 .615 .995 1.005 .995

logSI1 -.198c -4.412 .000 -.572 .982 1.018 .982

logShapFactr .120c 1.608 .116 .246 .495 2.019 .495

logChSlpDmls .592c 4.545 .000 .584 .114 8.741 .114

2 logSI1 -.147d -3.735 .001 -.513 .892 1.121 .892

logShapFactr .016d .241 .811 .038 .433 2.310 .433

logChSlpDmls .383d 2.913 .006 .423 .089 11.229 .089

3 logShapFactr -.009e -.158 .876 -.026 .427 2.342 .427

logChSlpDmls .205e 1.459 .153 .230 .068 14.727 .068

a. Region = Boreal Shield

b. Dependent Variable: logQ50

c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logMAP

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113

e. Predictors in the Model: (Constant), logAreaKm, logMAP, logSI1

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logMAP logSI1

1 1 1.923 1.000 .04 .04

2 .077 4.992 .96 .96

2 1 2.897 1.000 .00 .02 .00

2 .103 5.310 .00 .98 .00

3 .000 140.226 1.00 .01 1.00

3 1 3.770 1.000 .00 .01 .00 .01

2 .135 5.275 .00 .42 .00 .64

3 .094 6.334 .00 .57 .00 .25

4 .000 168.762 1.00 .00 1.00 .10

a. Region = Boreal Shield

b. Dependent Variable: logQ50

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value -.1801 2.7869 1.7272 .76658 43

Residual -.46136 .42615 .00000 .18287 43

Std. Predicted Value -2.488 1.382 .000 1.000 43

Std. Residual -2.431 2.246 .000 .964 43

a. Region = Boreal Shield

b. Dependent Variable: logQ50

Charts

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Region = Mixed WoodPlains

Descriptive Statisticsa

Mean Std. Deviation N

logQ50 1.9393 .37473 75

logAreaKm 2.2409 .34956 75

logMAP 2.9826 .04197 75

logSI1 .0390 .03444 75

logShapFactr 1.1352 .20216 75

logChSlpDmls -2.6722 .32149 75

a. Region = Mixed WoodPlains

Correlationsa

logQ50 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ50 1.000 .782 .147 -.557 .195 -.422

logAreaKm .782 1.000 .025 -.268 .340 -.532

logMAP .147 .025 1.000 .041 -.111 -.380

logSI1 -.557 -.268 .041 1.000 -.042 -.008

logShapFactr .195 .340 -.111 -.042 1.000 -.388

logChSlpDmls -.422 -.532 -.380 -.008 -.388 1.000

Sig. (1-tailed) logQ50 . .000 .104 .000 .047 .000

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logAreaKm .000 . .414 .010 .001 .000

logMAP .104 .414 . .363 .172 .000

logSI1 .000 .010 .363 . .360 .472

logShapFactr .047 .001 .172 .360 . .000

logChSlpDmls .000 .000 .000 .472 .000 .

N logQ50 75 75 75 75 75 75

logAreaKm 75 75 75 75 75 75

logMAP 75 75 75 75 75 75

logSI1 75 75 75 75 75 75

logShapFactr 75 75 75 75 75 75

logChSlpDmls 75 75 75 75 75 75

a. Region = Mixed WoodPlains

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ50

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .782b .611 .606 .23535

2 .861c .741 .734 .19319

3 .873d .763 .752 .18643 1.640

a. Region = Mixed WoodPlains

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logSI1

d. Predictors: (Constant), logAreaKm, logSI1, logMAP

e. Dependent Variable: logQ50

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 6.347 1 6.347 114.592 .000c

Residual 4.044 73 .055

Total 10.391 74

2 Regression 7.704 2 3.852 103.212 .000d

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Residual 2.687 72 .037

Total 10.391 74

3 Regression 7.923 3 2.641 75.991 .000e

Residual 2.468 71 .035

Total 10.391 74

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ50

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logSI1

e. Predictors: (Constant), logAreaKm, logSI1, logMAP

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) .062 .177 .348 .729

logAreaKm .838 .078 .782 10.705 .000 .782 .782 .782 1.000 1.000

2 (Constant) .462 .160 2.885 .005

logAreaKm .730 .067 .681 10.951 .000 .782 .790 .656 .928 1.077

logSI1 -4.080 .677 -.375 -6.029 .000 -.557 -.579 -.361 .928 1.077

3 (Constant) -3.397 1.544 -2.201 .031

logAreaKm .724 .064 .675 11.245 .000 .782 .800 .650 .927 1.079

logSI1 -4.162 .654 -.382 -6.364 .000 -.557 -.603 -.368 .926 1.080

logMAP 1.299 .517 .146 2.513 .014 .147 .286 .145 .997 1.003

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ50

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .127c 1.767 .081 .204 .999 1.001 .999

logSI1 -.375c -6.029 .000 -.579 .928 1.077 .928

logShapFactr -.080c -1.026 .308 -.120 .885 1.130 .885

logChSlpDmls -.009c -.101 .920 -.012 .717 1.395 .717

2 logMAP .146d 2.513 .014 .286 .997 1.003 .926

logShapFactr -.059d -.924 .359 -.109 .882 1.134 .820

logChSlpDmls -.091d -1.265 .210 -.148 .692 1.445 .643

3 logShapFactr -.040e -.634 .528 -.076 .867 1.153 .815

logChSlpDmls -.019e -.243 .809 -.029 .563 1.776 .563

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ50

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c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logSI1

e. Predictors in the Model: (Constant), logAreaKm, logSI1, logMAP

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logSI1 logMAP

1 1 1.988 1.000 .01 .01

2 .012 12.985 .99 .99

2 1 2.643 1.000 .00 .00 .04

2 .346 2.762 .01 .01 .83

3 .010 15.984 .99 .99 .13

3 1 3.612 1.000 .00 .00 .02 .00

2 .373 3.110 .00 .01 .87 .00

3 .014 16.053 .00 .99 .11 .00

4 9.755E-5 192.433 1.00 .00 .00 1.00

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ50

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value 1.1497 2.6462 1.9393 .32722 75

Residual -.39162 .40029 .00000 .18261 75

Std. Predicted Value -2.413 2.160 .000 1.000 75

Std. Residual -2.101 2.147 .000 .980 75

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ50

Charts

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Region = Boreal Shield

Descriptive Statisticsa

Mean Std. Deviation N

logQ25 1.6751 .79747 43

logAreaKm 2.3566 .99527 43

logMAP 2.9348 .05119 43

logSI1 .0575 .02563 43

logShapFactr 1.1180 .25951 43

logChSlpDmls -2.5392 .57989 43

a. Region = Boreal Shield

Correlationsa

logQ25 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ25 1.000 .941 .151 -.068 .730 -.818

logAreaKm .941 1.000 -.069 .134 .710 -.941

logMAP .151 -.069 1.000 -.309 .200 .224

logSI1 -.068 .134 -.309 1.000 -.053 -.311

logShapFactr .730 .710 .200 -.053 1.000 -.683

logChSlpDmls -.818 -.941 .224 -.311 -.683 1.000

Sig. (1-tailed) logQ25 . .000 .167 .332 .000 .000

logAreaKm .000 . .330 .195 .000 .000

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logMAP .167 .330 . .022 .100 .074

logSI1 .332 .195 .022 . .369 .021

logShapFactr .000 .000 .100 .369 . .000

logChSlpDmls .000 .000 .074 .021 .000 .

N logQ25 43 43 43 43 43 43

logAreaKm 43 43 43 43 43 43

logMAP 43 43 43 43 43 43

logSI1 43 43 43 43 43 43

logShapFactr 43 43 43 43 43 43

logChSlpDmls 43 43 43 43 43 43

a. Region = Boreal Shield

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Boreal Shield

b. Dependent Variable: logQ25

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .941b .885 .882 .27349

2 .965c .932 .929 .21293

3 .975d .951 .947 .18351 2.257

a. Region = Boreal Shield

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logMAP

d. Predictors: (Constant), logAreaKm, logMAP, logSI1

e. Dependent Variable: logQ25

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 23.643 1 23.643 316.097 .000c

Residual 3.067 41 .075

Total 26.710 42

2 Regression 24.897 2 12.448 274.569 .000d

Residual 1.814 40 .045

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Total 26.710 42

3 Regression 25.397 3 8.466 251.396 .000e

Residual 1.313 39 .034

Total 26.710 42

a. Region = Boreal Shield

b. Dependent Variable: logQ25

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logMAP

e. Predictors: (Constant), logAreaKm, logMAP, logSI1

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) -.101 .108 -.937 .354

logAreaKm .754 .042 .941 17.779 .000 .941 .941 .941 1.000 1.000

2 (Constant) -10.057 1.896 -5.306 .000

logAreaKm .766 .033 .956 23.145 .000 .941 .965 .954 .995 1.005

logMAP 3.383 .643 .217 5.258 .000 .151 .639 .217 .995 1.005

3 (Constant) -7.834 1.733 -4.521 .000

logAreaKm .779 .029 .972 27.124 .000 .941 .975 .963 .981 1.019

logMAP 2.703 .582 .173 4.645 .000 .151 .597 .165 .904 1.107

logSI1 -4.510 1.170 -.145 -3.854 .000 -.068 -.525 -.137 .892 1.121

a. Region = Boreal Shield

b. Dependent Variable: logQ25

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .217c 5.258 .000 .639 .995 1.005 .995

logSI1 -.198c -4.488 .000 -.579 .982 1.018 .982

logShapFactr .123c 1.677 .101 .256 .495 2.019 .495

logChSlpDmls .591c 4.620 .000 .590 .114 8.741 .114

2 logSI1 -.145d -3.854 .000 -.525 .892 1.121 .892

logShapFactr .016d .258 .798 .041 .433 2.310 .433

logChSlpDmls .372d 2.940 .005 .426 .089 11.229 .089

3 logShapFactr -.008e -.149 .882 -.024 .427 2.342 .427

logChSlpDmls .195e 1.448 .156 .229 .068 14.727 .068

a. Region = Boreal Shield

b. Dependent Variable: logQ25

c. Predictors in the Model: (Constant), logAreaKm

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d. Predictors in the Model: (Constant), logAreaKm, logMAP

e. Predictors in the Model: (Constant), logAreaKm, logMAP, logSI1

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logMAP logSI1

1 1 1.923 1.000 .04 .04

2 .077 4.992 .96 .96

2 1 2.897 1.000 .00 .02 .00

2 .103 5.310 .00 .98 .00

3 .000 140.226 1.00 .01 1.00

3 1 3.770 1.000 .00 .01 .00 .01

2 .135 5.275 .00 .42 .00 .64

3 .094 6.334 .00 .57 .00 .25

4 .000 168.762 1.00 .00 1.00 .10

a. Region = Boreal Shield

b. Dependent Variable: logQ25

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value -.2636 2.7478 1.6751 .77761 43

Residual -.45474 .42091 .00000 .17683 43

Std. Predicted Value -2.493 1.379 .000 1.000 43

Std. Residual -2.478 2.294 .000 .964 43

a. Region = Boreal Shield

b. Dependent Variable: logQ25

Charts

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Region = Mixed WoodPlains

Descriptive Statisticsa

Mean Std. Deviation N

logQ25 1.8874 .36920 75

logAreaKm 2.2409 .34956 75

logMAP 2.9826 .04197 75

logSI1 .0390 .03444 75

logShapFactr 1.1352 .20216 75

logChSlpDmls -2.6722 .32149 75

a. Region = Mixed WoodPlains

Correlationsa

logQ25 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ25 1.000 .793 .158 -.553 .196 -.439

logAreaKm .793 1.000 .025 -.268 .340 -.532

logMAP .158 .025 1.000 .041 -.111 -.380

logSI1 -.553 -.268 .041 1.000 -.042 -.008

logShapFactr .196 .340 -.111 -.042 1.000 -.388

logChSlpDmls -.439 -.532 -.380 -.008 -.388 1.000

Sig. (1-tailed) logQ25 . .000 .088 .000 .046 .000

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logAreaKm .000 . .414 .010 .001 .000

logMAP .088 .414 . .363 .172 .000

logSI1 .000 .010 .363 . .360 .472

logShapFactr .046 .001 .172 .360 . .000

logChSlpDmls .000 .000 .000 .472 .000 .

N logQ25 75 75 75 75 75 75

logAreaKm 75 75 75 75 75 75

logMAP 75 75 75 75 75 75

logSI1 75 75 75 75 75 75

logShapFactr 75 75 75 75 75 75

logChSlpDmls 75 75 75 75 75 75

a. Region = Mixed WoodPlains

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ25

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .793b .629 .624 .22635

2 .868c .754 .747 .18563

3 .882d .778 .769 .17747 1.659

a. Region = Mixed WoodPlains

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logSI1

d. Predictors: (Constant), logAreaKm, logSI1, logMAP

e. Dependent Variable: logQ25

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 6.347 1 6.347 123.889 .000c

Residual 3.740 73 .051

Total 10.087 74

2 Regression 7.606 2 3.803 110.362 .000d

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Residual 2.481 72 .034

Total 10.087 74

3 Regression 7.851 3 2.617 83.084 .000e

Residual 2.236 71 .031

Total 10.087 74

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ25

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logSI1

e. Predictors: (Constant), logAreaKm, logSI1, logMAP

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) .010 .171 .058 .954

logAreaKm .838 .075 .793 11.131 .000 .793 .793 .793 1.000 1.000

2 (Constant) .395 .154 2.570 .012

logAreaKm .734 .064 .695 11.458 .000 .793 .804 .670 .928 1.077

logSI1 -3.930 .650 -.367 -6.044 .000 -.553 -.580 -.353 .928 1.077

3 (Constant) -3.680 1.469 -2.505 .015

logAreaKm .728 .061 .689 11.871 .000 .793 .815 .663 .927 1.079

logSI1 -4.017 .622 -.375 -6.453 .000 -.553 -.608 -.361 .926 1.080

logMAP 1.372 .492 .156 2.788 .007 .158 .314 .156 .997 1.003

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ25

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .138c 1.975 .052 .227 .999 1.001 .999

logSI1 -.367c -6.044 .000 -.580 .928 1.077 .928

logShapFactr -.083c -1.094 .278 -.128 .885 1.130 .885

logChSlpDmls -.023c -.275 .784 -.032 .717 1.395 .717

2 logMAP .156d 2.788 .007 .314 .997 1.003 .926

logShapFactr -.063d -1.007 .317 -.119 .882 1.134 .820

logChSlpDmls -.104d -1.492 .140 -.174 .692 1.445 .643

3 logShapFactr -.042e -.694 .490 -.083 .867 1.153 .815

logChSlpDmls -.028e -.379 .706 -.045 .563 1.776 .563

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ25

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125

c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logSI1

e. Predictors in the Model: (Constant), logAreaKm, logSI1, logMAP

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logSI1 logMAP

1 1 1.988 1.000 .01 .01

2 .012 12.985 .99 .99

2 1 2.643 1.000 .00 .00 .04

2 .346 2.762 .01 .01 .83

3 .010 15.984 .99 .99 .13

3 1 3.612 1.000 .00 .00 .02 .00

2 .373 3.110 .00 .01 .87 .00

3 .014 16.053 .00 .99 .11 .00

4 9.755E-5 192.433 1.00 .00 .00 1.00

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ25

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value 1.0931 2.5910 1.8874 .32572 75

Residual -.38583 .38775 .00000 .17384 75

Std. Predicted Value -2.439 2.160 .000 1.000 75

Std. Residual -2.174 2.185 .000 .980 75

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ25

Charts

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Region = Boreal Shield

Descriptive Statisticsa

Mean Std. Deviation N

logQ10 1.5928 .81277 43

logAreaKm 2.3566 .99527 43

logMAP 2.9348 .05119 43

logSI1 .0575 .02563 43

logShapFactr 1.1180 .25951 43

logChSlpDmls -2.5392 .57989 43

a. Region = Boreal Shield

Correlationsa

logQ10 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ10 1.000 .942 .160 -.069 .734 -.819

logAreaKm .942 1.000 -.069 .134 .710 -.941

logMAP .160 -.069 1.000 -.309 .200 .224

logSI1 -.069 .134 -.309 1.000 -.053 -.311

logShapFactr .734 .710 .200 -.053 1.000 -.683

logChSlpDmls -.819 -.941 .224 -.311 -.683 1.000

Sig. (1-tailed) logQ10 . .000 .152 .331 .000 .000

logAreaKm .000 . .330 .195 .000 .000

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127

logMAP .152 .330 . .022 .100 .074

logSI1 .331 .195 .022 . .369 .021

logShapFactr .000 .000 .100 .369 . .000

logChSlpDmls .000 .000 .074 .021 .000 .

N logQ10 43 43 43 43 43 43

logAreaKm 43 43 43 43 43 43

logMAP 43 43 43 43 43 43

logSI1 43 43 43 43 43 43

logShapFactr 43 43 43 43 43 43

logChSlpDmls 43 43 43 43 43 43

a. Region = Boreal Shield

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter <=

.050, Probability-of-F-to-remove >= .100).

2 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter <=

.050, Probability-of-F-to-remove >= .100).

3 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter <=

.050, Probability-of-F-to-remove >= .100).

a. Region = Boreal Shield

b. Dependent Variable: logQ10

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .942b .888 .885 .27563

2 .969c .939 .936 .20594

3 .978d .957 .954 .17493 2.232

a. Region = Boreal Shield

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logMAP

d. Predictors: (Constant), logAreaKm, logMAP, logSI1

e. Dependent Variable: logQ10

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 24.630 1 24.630 324.195 .000c

Residual 3.115 41 .076

Total 27.745 42

2 Regression 26.049 2 13.024 307.105 .000d

Residual 1.696 40 .042

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128

Total 27.745 42

3 Regression 26.552 3 8.851 289.223 .000e

Residual 1.193 39 .031

Total 27.745 42

a. Region = Boreal Shield

b. Dependent Variable: logQ10

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logMAP

e. Predictors: (Constant), logAreaKm, logMAP, logSI1

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) -.221 .109 -2.021 .050

logAreaKm .769 .043 .942 18.005 .000 .942 .942 .942 1.000 1.000

2 (Constant) -10.813 1.833 -5.898 .000

logAreaKm .782 .032 .958 24.442 .000 .942 .968 .956 .995 1.005

logMAP 3.599 .622 .227 5.783 .000 .160 .675 .226 .995 1.005

3 (Constant) -8.583 1.652 -5.197 .000

logAreaKm .795 .027 .974 29.052 .000 .942 .978 .965 .981 1.019

logMAP 2.917 .555 .184 5.259 .000 .160 .644 .175 .904 1.107

logSI1 -4.522 1.115 -.143 -4.054 .000 -.069 -.545 -.135 .892 1.121

a. Region = Boreal Shield

b. Dependent Variable: logQ10

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .227c 5.783 .000 .675 .995 1.005 .995

logSI1 -.199c -4.592 .000 -.588 .982 1.018 .982

logShapFactr .130c 1.794 .080 .273 .495 2.019 .495

logChSlpDmls .593c 4.722 .000 .598 .114 8.741 .114

2 logSI1 -.143d -4.054 .000 -.545 .892 1.121 .892

logShapFactr .018d .305 .762 .049 .433 2.310 .433

logChSlpDmls .357d 2.983 .005 .431 .089 11.229 .089

3 logShapFactr -.006e -.112 .911 -.018 .427 2.342 .427

logChSlpDmls .180e 1.432 .160 .226 .068 14.727 .068

a. Region = Boreal Shield

b. Dependent Variable: logQ10

c. Predictors in the Model: (Constant), logAreaKm

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d. Predictors in the Model: (Constant), logAreaKm, logMAP

e. Predictors in the Model: (Constant), logAreaKm, logMAP, logSI1

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logMAP logSI1

1 1 1.923 1.000 .04 .04

2 .077 4.992 .96 .96

2 1 2.897 1.000 .00 .02 .00

2 .103 5.310 .00 .98 .00

3 .000 140.226 1.00 .01 1.00

3 1 3.770 1.000 .00 .01 .00 .01

2 .135 5.275 .00 .42 .00 .64

3 .094 6.334 .00 .57 .00 .25

4 .000 168.762 1.00 .00 1.00 .10

a. Region = Boreal Shield

b. Dependent Variable: logQ10

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value -.3970 2.6864 1.5928 .79510 43

Residual -.44448 .41232 .00000 .16857 43

Std. Predicted Value -2.503 1.375 .000 1.000 43

Std. Residual -2.541 2.357 .000 .964 43

a. Region = Boreal Shield

b. Dependent Variable: logQ10

Charts

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Region = Mixed WoodPlains

Descriptive Statisticsa

Mean Std. Deviation N

logQ10 1.8054 .36207 75

logAreaKm 2.2409 .34956 75

logMAP 2.9826 .04197 75

logSI1 .0390 .03444 75

logShapFactr 1.1352 .20216 75

logChSlpDmls -2.6722 .32149 75

a. Region = Mixed WoodPlains

Correlationsa

logQ10 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ10 1.000 .809 .176 -.542 .197 -.464

logAreaKm .809 1.000 .025 -.268 .340 -.532

logMAP .176 .025 1.000 .041 -.111 -.380

logSI1 -.542 -.268 .041 1.000 -.042 -.008

logShapFactr .197 .340 -.111 -.042 1.000 -.388

logChSlpDmls -.464 -.532 -.380 -.008 -.388 1.000

Sig. (1-tailed) logQ10 . .000 .065 .000 .045 .000

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logAreaKm .000 . .414 .010 .001 .000

logMAP .065 .414 . .363 .172 .000

logSI1 .000 .010 .363 . .360 .472

logShapFactr .045 .001 .172 .360 . .000

logChSlpDmls .000 .000 .000 .472 .000 .

N logQ10 75 75 75 75 75 75

logAreaKm 75 75 75 75 75 75

logMAP 75 75 75 75 75 75

logSI1 75 75 75 75 75 75

logShapFactr 75 75 75 75 75 75

logChSlpDmls 75 75 75 75 75 75

a. Region = Mixed WoodPlains

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ10

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .809b .655 .650 .21424

2 .877c .769 .762 .17651

3 .894d .799 .790 .16590 1.691

a. Region = Mixed WoodPlains

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logSI1

d. Predictors: (Constant), logAreaKm, logSI1, logMAP

e. Dependent Variable: logQ10

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 6.350 1 6.350 138.357 .000c

Residual 3.351 73 .046

Total 9.701 74

2 Regression 7.458 2 3.729 119.690 .000d

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Residual 2.243 72 .031

Total 9.701 74

3 Regression 7.747 3 2.582 93.819 .000e

Residual 1.954 71 .028

Total 9.701 74

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ10

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logSI1

e. Predictors: (Constant), logAreaKm, logSI1, logMAP

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) -.073 .162 -.449 .655

logAreaKm .838 .071 .809 11.763 .000 .809 .809 .809 1.000 1.000

2 (Constant) .289 .146 1.976 .052

logAreaKm .741 .061 .715 12.160 .000 .809 .820 .689 .928 1.077

logSI1 -3.687 .618 -.351 -5.962 .000 -.542 -.575 -.338 .928 1.077

3 (Constant) -4.139 1.374 -3.013 .004

logAreaKm .734 .057 .708 12.805 .000 .809 .835 .682 .927 1.079

logSI1 -3.780 .582 -.360 -6.496 .000 -.542 -.611 -.346 .926 1.080

logMAP 1.491 .460 .173 3.240 .002 .176 .359 .173 .997 1.003

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ10

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .156c 2.330 .023 .265 .999 1.001 .999

logSI1 -.351c -5.962 .000 -.575 .928 1.077 .928

logShapFactr -.088c -1.205 .232 -.141 .885 1.130 .885

logChSlpDmls -.046c -.569 .571 -.067 .717 1.395 .717

2 logMAP .173d 3.240 .002 .359 .997 1.003 .926

logShapFactr -.069d -1.140 .258 -.134 .882 1.134 .820

logChSlpDmls -.124d -1.859 .067 -.215 .692 1.445 .643

3 logShapFactr -.046e -.794 .430 -.094 .867 1.153 .815

logChSlpDmls -.043e -.602 .549 -.072 .563 1.776 .563

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ10

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c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logSI1

e. Predictors in the Model: (Constant), logAreaKm, logSI1, logMAP

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logSI1 logMAP

1 1 1.988 1.000 .01 .01

2 .012 12.985 .99 .99

2 1 2.643 1.000 .00 .00 .04

2 .346 2.762 .01 .01 .83

3 .010 15.984 .99 .99 .13

3 1 3.612 1.000 .00 .00 .02 .00

2 .373 3.110 .00 .01 .87 .00

3 .014 16.053 .00 .99 .11 .00

4 9.755E-5 192.433 1.00 .00 .00 1.00

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ10

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value 1.0032 2.5038 1.8054 .32355 75

Residual -.37517 .36837 .00000 .16250 75

Std. Predicted Value -2.479 2.159 .000 1.000 75

Std. Residual -2.261 2.220 .000 .980 75

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ10

Charts

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Region = Boreal Shield

Descriptive Statisticsa

Mean Std. Deviation N

logQ2 1.3572 .85698 43

logAreaKm 2.3566 .99527 43

logMAP 2.9348 .05119 43

logSI1 .0575 .02563 43

logShapFactr 1.1180 .25951 43

logChSlpDmls -2.5392 .57989 43

a. Region = Boreal Shield

Correlationsa

logQ2 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ2 1.000 .941 .189 -.074 .745 -.815

logAreaKm .941 1.000 -.069 .134 .710 -.941

logMAP .189 -.069 1.000 -.309 .200 .224

logSI1 -.074 .134 -.309 1.000 -.053 -.311

logShapFactr .745 .710 .200 -.053 1.000 -.683

logChSlpDmls -.815 -.941 .224 -.311 -.683 1.000

Sig. (1-tailed) logQ2 . .000 .112 .319 .000 .000

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logAreaKm .000 . .330 .195 .000 .000

logMAP .112 .330 . .022 .100 .074

logSI1 .319 .195 .022 . .369 .021

logShapFactr .000 .000 .100 .369 . .000

logChSlpDmls .000 .000 .074 .021 .000 .

N logQ2 43 43 43 43 43 43

logAreaKm 43 43 43 43 43 43

logMAP 43 43 43 43 43 43

logSI1 43 43 43 43 43 43

logShapFactr 43 43 43 43 43 43

logChSlpDmls 43 43 43 43 43 43

a. Region = Boreal Shield

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Boreal Shield

b. Dependent Variable: logQ2

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .941b .886 .883 .29347

2 .975c .951 .948 .19513

3 .984d .968 .965 .15973 2.167

a. Region = Boreal Shield

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logMAP

d. Predictors: (Constant), logAreaKm, logMAP, logSI1

e. Dependent Variable: logQ2

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 27.314 1 27.314 317.156 .000c

Residual 3.531 41 .086

Total 30.845 42

2 Regression 29.322 2 14.661 385.063 .000d

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Residual 1.523 40 .038

Total 30.845 42

3 Regression 29.850 3 9.950 390.009 .000e

Residual .995 39 .026

Total 30.845 42

a. Region = Boreal Shield

b. Dependent Variable: logQ2

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logMAP

e. Predictors: (Constant), logAreaKm, logMAP, logSI1

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) -.552 .116 -4.753 .000

logAreaKm .810 .045 .941 17.809 .000 .941 .941 .941 1.000 1.000

2 (Constant) -13.155 1.737 -7.573 .000

logAreaKm .826 .030 .959 27.223 .000 .941 .974 .956 .995 1.005

logMAP 4.282 .590 .256 7.262 .000 .189 .754 .255 .995 1.005

3 (Constant) -10.870 1.508 -7.208 .000

logAreaKm .839 .025 .974 33.561 .000 .941 .983 .965 .981 1.019

logMAP 3.583 .507 .214 7.075 .000 .189 .750 .203 .904 1.107

logSI1 -4.633 1.018 -.139 -4.549 .000 -.074 -.589 -.131 .892 1.121

a. Region = Boreal Shield

b. Dependent Variable: logQ2

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .256c 7.262 .000 .754 .995 1.005 .995

logSI1 -.204c -4.708 .000 -.597 .982 1.018 .982

logShapFactr .153c 2.129 .039 .319 .495 2.019 .495

logChSlpDmls .613c 4.905 .000 .613 .114 8.741 .114

2 logSI1 -.139d -4.549 .000 -.589 .892 1.121 .892

logShapFactr .028d .527 .601 .084 .433 2.310 .433

logChSlpDmls .331d 3.103 .004 .445 .089 11.229 .089

3 logShapFactr .005e .115 .909 .019 .427 2.342 .427

logChSlpDmls .154e 1.416 .165 .224 .068 14.727 .068

a. Region = Boreal Shield

b. Dependent Variable: logQ2

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c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logMAP

e. Predictors in the Model: (Constant), logAreaKm, logMAP, logSI1

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logMAP logSI1

1 1 1.923 1.000 .04 .04

2 .077 4.992 .96 .96

2 1 2.897 1.000 .00 .02 .00

2 .103 5.310 .00 .98 .00

3 .000 140.226 1.00 .01 1.00

3 1 3.770 1.000 .00 .01 .00 .01

2 .135 5.275 .00 .42 .00 .64

3 .094 6.334 .00 .57 .00 .25

4 .000 168.762 1.00 .00 1.00 .10

a. Region = Boreal Shield

b. Dependent Variable: logQ2

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value -.7794 2.5082 1.3572 .84304 43

Residual -.40212 .37227 .00000 .15392 43

Std. Predicted Value -2.534 1.365 .000 1.000 43

Std. Residual -2.518 2.331 .000 .964 43

a. Region = Boreal Shield

b. Dependent Variable: logQ2

Charts

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Region = Mixed WoodPlains

Descriptive Statisticsa

Mean Std. Deviation N

logQ2 1.5694 .35051 75

logAreaKm 2.2409 .34956 75

logMAP 2.9826 .04197 75

logSI1 .0390 .03444 75

logShapFactr 1.1352 .20216 75

logChSlpDmls -2.6722 .32149 75

a. Region = Mixed WoodPlains

Correlationsa

logQ2 logAreaKm logMAP logSI1 logShapFactr logChSlpDmls

Pearson

Correlation

logQ2 1.000 .840 .227 -.494 .196 -.530

logAreaKm .840 1.000 .025 -.268 .340 -.532

logMAP .227 .025 1.000 .041 -.111 -.380

logSI1 -.494 -.268 .041 1.000 -.042 -.008

logShapFactr .196 .340 -.111 -.042 1.000 -.388

logChSlpDmls -.530 -.532 -.380 -.008 -.388 1.000

Sig. (1-tailed) logQ2 . .000 .025 .000 .046 .000

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logAreaKm .000 . .414 .010 .001 .000

logMAP .025 .414 . .363 .172 .000

logSI1 .000 .010 .363 . .360 .472

logShapFactr .046 .001 .172 .360 . .000

logChSlpDmls .000 .000 .000 .472 .000 .

N logQ2 75 75 75 75 75 75

logAreaKm 75 75 75 75 75 75

logMAP 75 75 75 75 75 75

logSI1 75 75 75 75 75 75

logShapFactr 75 75 75 75 75 75

logChSlpDmls 75 75 75 75 75 75

a. Region = Mixed WoodPlains

Variables Entered/Removeda,b

Model

Variables

Entered

Variables

Removed Method

1 logAreaKm .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

2 logSI1 .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

3 logMAP .

Stepwise (Criteria: Probability-of-F-to-enter

<= .050, Probability-of-F-to-remove >= .100).

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ2

Model Summarya,e

Model R R Square

Adjusted R

Square

Std. Error of the

Estimate Durbin-Watson

1 .840b .705 .701 .19163

2 .885c .783 .777 .16555

3 .912d .831 .824 .14704 1.763

a. Region = Mixed WoodPlains

b. Predictors: (Constant), logAreaKm

c. Predictors: (Constant), logAreaKm, logSI1

d. Predictors: (Constant), logAreaKm, logSI1, logMAP

e. Dependent Variable: logQ2

ANOVAa,b

Model Sum of Squares df Mean Square F Sig.

1 Regression 6.411 1 6.411 174.573 .000c

Residual 2.681 73 .037

Total 9.091 74

2 Regression 7.118 2 3.559 129.848 .000d

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Residual 1.973 72 .027

Total 9.091 74

3 Regression 7.556 3 2.519 116.505 .000e

Residual 1.535 71 .022

Total 9.091 74

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ2

c. Predictors: (Constant), logAreaKm

d. Predictors: (Constant), logAreaKm, logSI1

e. Predictors: (Constant), logAreaKm, logSI1, logMAP

Coefficientsa,b

Model

Unstandardized

Coefficients

Standardized

Coefficients

t Sig.

Correlations

Collinearity

Statistics

B

Std.

Error Beta

Zero-

order Partial Part Tolerance VIF

1 (Constant) -.317 .145 -2.196 .031

logAreaKm .842 .064 .840 13.213 .000 .840 .840 .840 1.000 1.000

2 (Constant) -.028 .137 -.207 .836

logAreaKm .764 .057 .762 13.375 .000 .840 .844 .734 .928 1.077

logSI1 -2.946 .580 -.289 -5.080 .000 -.494 -.514 -.279 .928 1.077

3 (Constant) -5.483 1.217 -4.504 .000

logAreaKm .756 .051 .754 14.879 .000 .840 .870 .726 .927 1.079

logSI1 -3.061 .516 -.301 -5.936 .000 -.494 -.576 -.289 .926 1.080

logMAP 1.837 .408 .220 4.503 .000 .227 .471 .220 .997 1.003

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ2

Excluded Variablesa,b

Model Beta In t Sig.

Partial

Correlation

Collinearity Statistics

Tolerance VIF

Minimum

Tolerance

1 logMAP .206c 3.469 .001 .378 .999 1.001 .999

logSI1 -.289c -5.080 .000 -.514 .928 1.077 .928

logShapFactr -.100c -1.499 .138 -.174 .885 1.130 .885

logChSlpDmls -.116c -1.561 .123 -.181 .717 1.395 .717

2 logMAP .220d 4.503 .000 .471 .997 1.003 .926

logShapFactr -.085d -1.460 .149 -.171 .882 1.134 .820

logChSlpDmls -.183d -2.917 .005 -.327 .692 1.445 .643

3 logShapFactr -.055e -1.055 .295 -.125 .867 1.153 .815

logChSlpDmls -.085e -1.316 .193 -.155 .563 1.776 .563

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ2

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141

c. Predictors in the Model: (Constant), logAreaKm

d. Predictors in the Model: (Constant), logAreaKm, logSI1

e. Predictors in the Model: (Constant), logAreaKm, logSI1, logMAP

Collinearity Diagnosticsa,b

Model Dimension Eigenvalue

Condition

Index

Variance Proportions

(Constant) logAreaKm logSI1 logMAP

1 1 1.988 1.000 .01 .01

2 .012 12.985 .99 .99

2 1 2.643 1.000 .00 .00 .04

2 .346 2.762 .01 .01 .83

3 .010 15.984 .99 .99 .13

3 1 3.612 1.000 .00 .00 .02 .00

2 .373 3.110 .00 .01 .87 .00

3 .014 16.053 .00 .99 .11 .00

4 9.755E-5 192.433 1.00 .00 .00 1.00

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ2

Residuals Statisticsa,b

Minimum Maximum Mean Std. Deviation N

Predicted Value .7393 2.2555 1.5694 .31955 75

Residual -.33889 .31825 .00000 .14402 75

Std. Predicted Value -2.598 2.147 .000 1.000 75

Std. Residual -2.305 2.164 .000 .980 75

a. Region = Mixed WoodPlains

b. Dependent Variable: logQ2

Charts

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Appendix G: Stations rejected from Multiple Regression Analysis

S. No. Station ID Reason for rejection

1 02HB021 Urban station

2 04DB001 Rejection due to lack of OFAT data

3 04FB001 Rejection due to non parametric test

4 04FC001 Rejection due to lack of OFAT data

5 05PA012 Rejection due to lack of OFAT data

6 02GG009 Rejection due to lack of OFAT data

7 02EC011 Rejection due to non parametric test

8 02BB002 Rejection during fitting

9 02JC008 Rejection due to non parametric test

10 02HE001 Rejection due to non parametric test

11 02CG003 rejection due to area mismatch

12 02HF004 rejection due to area mismatch

13 02MB010 rejection due to area mismatch

14 02GA036 Rejection due to data<15yrs

15 02GH003 rejection due to area mismatch

16 02KF011 Rejection due to non parametric test

17 04GA002 Rejection due to non parametric test

18 05QE008 Rejection due to non parametric test

19 02DD014 Urban station

20 02ED007 Rejection due to non parametric test

21 02HM005 Rejection due to non parametric test

22 02GA017 Rejection during fitting

23 02DB007 rejection due to area mismatch

24 02DB004 Rejection due to data<15yrs

25 02GE005 Urban station

26 02GA035 Rejection due to data<15yrs

27 04EA001 Rejection due to lack of OFAT data

28 05QA002 rejection due to area mismatch

29 02HC030 Urban station

30 02HC002 Rejection due to non parametric test

31 04CE002 Rejection due to lack of OFAT data

32 02GD010 Rejection due to non parametric test

33 02HD002 Rejection due to non parametric test

34 02KF015 rejection due to area mismatch

35 04KA002 Rejection due to lack of OFAT data

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S. No. Station ID Reason for rejection

36 02HD013 Rejection due to non parametric test

37 02HC013 Rejection due to non parametric test

38 02EC009 Urban station

39 02GA045 Rejection due to data<15yrs

40 02GA046 Rejection due to data<15yrs

41 02HJ001 Rejection due to non parametric test

42 02LA007 Rejection due to non parametric test

43 02CF012 Urban station

44 04KA001 reject-Hudson Plain

45 05PC016 Rejection due to data<15yrs

46 05QD018 Rejection due to non parametric test

47 05QD019 rejection due to area mismatch

48 05QD015 Rejection due to lack of OFAT data

49 05QD008 Rejection due to lack of OFAT data

50 05PD024 Rejection due to data<15yrs

51 05PD015 Rejection due to non parametric test

52 02HC029 Rejection due to non parametric test

53 02HC004 Rejection due to non parametric test

54 02DD020 Rejection due to data<15yrs

55 02GH011 Urban station

56 05QE012 Rejection due to non parametric test

57 02FD002 rejection due to area mismatch

58 02MA001 Rejection due to non parametric test

59 02AB019 Rejection due to non parametric test

60 02HC033 Urban station

61 04LJ001 Rejection due to lack of OFAT data

62 04LM001 Rejection due to lack of OFAT data

63 02BE001 Rejection due to data<15yrs

64 02GA042 Rejection due to data<15yrs

65 02KC015 Rejection due to data<15yrs

66 04GF001 Rejection due to lack of OFAT data

67 05PA006 rejection due to area mismatch

68 02GA018 Rejection due to non parametric test

69 02GA010 Rejection due to non parametric test

70 02BF012 rejection due to area mismatch

71 04MF001 reject-Hudson Plain

72 02EA005 rejection due to area mismatch

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S. No. Station ID Reason for rejection

73 05PD022 Rejection due to lack of OFAT data

74 02ED101 Rejection during fitting

75 02GF001 Rejection due to data<15yrs

76 02GA032 Rejection due to lack of OFAT data

77 04GB004 Rejection due to lack of OFAT data

78 02HD008 Rejection due to non parametric test

79 02HA024 Rejection due to non parametric test

80 04JD005 Rejection during fitting

81 02FF003 rejection due to area mismatch

82 04GA003 Rejection due to data<15yrs

83 02EC018 Rejection during fitting

84 02KA004 Rejection due to lack of OFAT data

85 02KA005 Rejection due to non parametric test

86 02KA006 Rejection due to lack of OFAT data

87 02KA007 Rejection due to lack of OFAT data

88 02KA008 Rejection due to lack of OFAT data

89 02KA003 rejection due to area mismatch

90 02AA001 rejection due to area mismatch

91 05OD032 Rejection due to lack of OFAT data

92 02ED014 Rejection due to non parametric test

93 04FA003 Rejection due to lack of OFAT data

94 05PB015 rejection due to area mismatch

95 04DA001 rejection due to area mismatch

96 04MD004 Rejection during fitting

97 02BC005 Rejection due to data<15yrs

98 05PC018 rejection due to area mismatch

99 02MC027 Rejection due to data<15yrs

100 02MC001 rejection due to area mismatch

101 02HA023 Urban station

102 02HA014 Rejection due to non parametric test

103 02MC028 Rejection due to data<15yrs

104 02FC004 Rejection due to data<15yrs

105 05OD030 Rejection due to lack of OFAT data

106 02GH002 Rejection due to non parametric test

107 04CD002 Rejection due to non parametric test

108 02FC016 Rejection during fitting

109 02GA037 rejection due to area mismatch

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S. No. Station ID Reason for rejection

110 02EC010 rejection due to area mismatch

111 04CC001 reject-Hudson Plain

112 04CA004 Rejection due to lack of OFAT data

113 04CA002 Rejection due to lack of OFAT data

114 04DC002 Rejection due to non parametric test

115 02GA044 Rejection due to data<15yrs

116 02HL004 Rejection due to non parametric test

117 02LB031 Rejection due to data<15yrs

118 02LB007 Rejection due to non parametric test

119 02MC030 Rejection due to data<15yrs

120 05OD031 Rejection due to lack of OFAT data

121 02FA002 rejection due to area mismatch

122 02HA022 rejection due to area mismatch

123 02GH001 Rejection due to non parametric test

124 02DC012 rejection due to area mismatch

125 05PC010 Rejection due to data<15yrs

126 02FB007 Rejection during fitting

127 02GD006 Rejection due to data<15yrs

128 02BF013 rejection due to area mismatch

129 02GD019 rejection due to area mismatch

130 02GD009 Rejection due to non parametric test

131 05QC003 Rejection due to non parametric test

132 02GH004 rejection due to area mismatch

133 05PB014 Rejection due to lack of OFAT data

134 02GC021 rejection due to area mismatch

135 02DD012 rejection due to area mismatch

136 02GD020 Rejection due to non parametric test

137 02HM009 rejection due to area mismatch

138 02HC038 rejection due to area mismatch

139 02BA005 rejection due to area mismatch

140 02CF007 Rejection due to non parametric test

141 02ED010 Rejection due to non parametric test

142 02HM004 Rejection due to non parametric test

143 04DC001 Rejection due to lack of OFAT data

144 02AC001 Rejection during fitting

145 02GD013 Rejection due to non parametric test

146 02KD002 Rejection due to non parametric test

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Copyright Acknowledgement

This project was supported by the Ontario Ministry of Transportation (MTO) under its Highway

Infrastructure Innovation and Funding Program (HIIFP). The author has also produced a project

report for MTO. The contents of the thesis and results would find similarity with the final project

report submitted to MTO in December 2015. A publication based on this thesis is also currently

in progress.