Trans Mountain Attachment 1 Condition 16 Final.Docx Page Iii BGC ENGINEERING INC

BGC ENGINEERING INC. AN APPLIED EARTH SCIENCES COMPANY

TRANS MOUNTAIN PIPELINE ULC

TRANS MOUNTAIN EXPANSION PROJECT

QUANTITATIVE GEOHAZARD FREQUENCY ASSESSMENT – POST MITIGATION

PROJECT NO.: 0095150-22 DISTRIBUTION: DATE: February 27, 2017 TMP ULC: e-copy BGC: e-copy

Trans Mountain Pipeline ULC, Trans Mountain Expansion Project February 27, 2017 Quantitative Geohazard Frequency Assessment – Post Mitigation Project No.: 0095150-22

EXECUTIVE SUMMARY

Trans Mountain Pipeline ULC (Trans Mountain) has retained BGC Engineering Inc. (BGC) to undertake a Quantitative Geohazard Frequency Assessment for the Trans Mountain Expansion Project (TMEP). In 2014, BGC undertook a quantitative frequency assessment of geohazards along the proposed TMEP route where the new pipeline will be constructed. The report contained herein is an update to the quantitative frequency assessment of geohazards along the proposed TMEP route. It has been updated to incorporate a review of additional data sources that were not available for the original analysis completed in 2014, data collected during site specific field assessments, and the predicted effects of site specific mitigations. The purpose of the assessment is to evaluate each potential geohazard with respect to its ability to impact the Line 2 and result in loss of containment (LoC). Results from this updated analysis were used as part of a broader hazard and risk assessment for the proposed pipeline and associated infrastructure (to be carried out by others), to identify areas for further study or that require additional mitigations, and to fulfil Condition 16 of OC-064. For this assessment, a systematic procedure was used to assign quantitative values to qualitative parameters that describe each potential geohazard site to estimate the frequency of a LoC (FLoC) event for the pipeline due to geohazards. The approach is considered appropriate for the intent described above where historical data associated with the frequency, spatial impact, and vulnerability of the individual geohazards must be supplemented with subjective estimates of probabilities (through engineering judgment). The broader pipeline hazard and risk assessment requires a numerical estimate of the FLoC from geohazards that can be compared with FLoC estimates for other threats to the pipeline that are being prepared by others. Similar approaches for geohazard analyses have been employed by other large-scale oil and gas development projects in Canada, including the Mackenzie Gas Project (submitted to the National Energy Board in 2004) and the Northern Gateway Project (submitted to the National Energy Board in 2010). The geohazard frequency assessment method uses six factors that provide a numerical value for the FLoC in terms of events per year from a geohazard for a specific location along the pipeline.

The factors include Occurrence (I), Frequency (F), Horizontal Spatial (SH), Vertical Spatial (SV), Vulnerability (V), and Mitigation (M) and the basis for each of the factors is described in the body and appendices of this report. The equation used to estimate the FLoC from a geohazard, at a specific location along the pipeline denoted with the subscript (i), is as follows:

FLoC(i) = I(i) x F(i) x SH(i) SV(i) x V(i) x M(I(i),F(i),SH(i), SV(i),V(i)) The updated geohazard assessment was completed on the Route SSEID 005 alignment. The previous version of this report was based on the Route Version 9 corridor that was filed in Technical Update No. 1, August, 2014. This updated report includes recently identified

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geohazards based on site specific fieldwork or a review of complete LiDAR coverage along the alignment. The geohazards assessed in this report include soil, rock, and hydrotechnical hazards. The National Energy Board’s (NEB) Condition 16 of OC-064 requires: Trans Mountain must file with the NEB, at least 6 months prior to commencing construction, an updated Quantitative Geohazard Frequency Assessment for the Line 2 and delivery pipeline segments that contains a re-assessment of the Frequency of Loss of Containment (FLoC) values based on the results of site-specific field assessments and any required mitigation as determined in the detailed engineering and design process. Trans Mountain must provide in the assessment a plan to manage and mitigate geohazards at any location where the FLoC is greater than 10-5 events per year to reduce the level of risk to as low as reasonably practicable (ALARP), including a detailed explanation of how ALARP level has been attained at each location. The NEB has indicated that Trans Mountain must provide a plan to manage and mitigate geohazard locations that have a FLoC value greater than 10-5 events per year to reduce the level of risk to as low as reasonably practicable (ALARP). The FLoC value of 10-5 is hereinafter referred to as the “threshold” value for the purposes of this report. This assessment incorporates the anticipated effects of mitigation designs on FLoC values that have been applied for geohazard sites that have a pre-mitigated FLoC greater than 10-5. The mitigation measures reduce the FLoC value at each site by modifying one or more of the FLoC factors. A range of modification values for each of the factors for the potential mitigation measures are provided in Appendix A. The range in the mitigation values in Appendix A represent the expected reduction in the FLoC factor if the proposed mitigations are applied during construction. Of the 1,569 credible geohazard segments, 220 have pre-mitigated FLoC values greater than 1 x 10- 5 events per year. The application of mitigations reduces the number of segments that will have a FLoC greater than 1 x 10-5 events per year to 40, with the remaining 180 segments having a FLoC value equal to or less than 1 x 10-5 events per year. Of the 40 segments, 27 of the segments are related to rock slope geohazards, one segment is a soil slope geohazard, and the remaining 12 segments are hydrotechnical hazards. Table 5 and Appendix D contains a summary of the 40 segments along with methods for reducing these sites to ALARP.

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TABLE OF CONTENTS

EXECUTIVE SUMMARY ...... iii TABLE OF CONTENTS ...... v LIST OF TABLES ...... vi LIST OF FIGURES ...... vi LIST OF APPENDICES ...... vi LIMITATIONS ...... vii 1.0 INTRODUCTION ...... 1 2.0 GEOHAZARD FREQUENCY ASSESSMENT METHODOLOGY ...... 2 2.1. Risk Assessment Framework ...... 2 2.2. Definitions and Key Concepts ...... 2 2.2.1. Hazard ...... 2 2.2.2. Hazard Identification ...... 2 2.2.3. Risk ...... 4 2.3. Geohazard Frequency Analysis ...... 4 2.3.1. Occurrence Factor (I) ...... 5 2.3.2. Annual Frequency of Geohazard Occurrence (F) ...... 5

2.3.3. Horizontal Spatial Probability of Impact (SH) ...... 6

2.3.4. Vertical Spatial Probability of Impact (SV) ...... 6 2.3.5. Vulnerability (V) ...... 6 2.3.6. Mitigation (M) ...... 6 2.3.7. FLoC Uncertainty ...... 7 3.0 TMEP GEOHAZARD FREQUENCY ASSESSMENT ...... 9 3.1. Geographic Extent of Assessment ...... 9 3.2. Data Sources and Assessments Used in the Updated Geohazard Analysis ...... 9 3.3. Geohazards Assessed ...... 11 3.4. Other Geohazards ...... 12 3.4.1. Karst ...... 12 3.4.2. Acid Rock Drainage and Metal Leaching ...... 12 3.4.3. Tsunami ...... 13 3.5. FLoC Threshold ...... 13 3.6. Geohazard Frequency Assessment ...... 14 3.6.1. Mitigation Assessment ...... 14 4.0 RESULTS ...... 16 5.0 CLOSURE ...... 19 REFERENCES ...... 20

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LIST OF TABLES

Table 1. Summary of assessed geohazards...... 11 Table 2. Summary of the pre- and post-mitigated geohazard results...... 17 Table 3. Detailed summary of post-mitigated geohazard FLoC greater than 10-5 events per year...... 17 Table 4. Summary of post mitigated geohazard FLoC greater than 10-5 events per year by geohazard class and category...... 18 Table 5. Summary of geohazard reduction strategies for geohazard segments with post- mitigated FLoC greater than 10-5...... 23

LIST OF FIGURES

Figure 1. Risk Management Framework (from CSA Z662)...... 3 Figure 2. Mitigation assessment flow chart...... 15 Figure 3. Number of pre- and post-mitigated geohazards along the proposed TMEP alignment with FLoC > 10-5 events per year...... 18

LIST OF APPENDICES

TABLE 5 Summary of geohazard reduction strategies for geohazard segments with post- mitigated FLoC greater than 10-5 Appendix A Geohazard Ranking Sheets Appendix B List of Geohazards by KP Appendix C List of Geohazards by Geohazard Type Appendix D Details of Geohazards with FLoC Values > 1 x 10-5

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LIMITATIONS

BGC Engineering Inc. (BGC) prepared this document for Trans Mountain Pipeline ULC (Trans Mountain). The material in this report reflects the judgment of BGC staff based upon the information made available to BGC at the time of preparation of the report, including that information provided to it by Trans Mountain. Any use which a third party makes of this report or any reliance on decisions to be based on it is the responsibility of such third parties. BGC accepts no responsibility whatsoever for damages, loss, expenses, loss of profit or revenues, if any, suffered by any third party because of decisions made or actions based on this report. As a mutual protection to our client, the public and BGC, the report, and its drawings are submitted to Trans Mountain as confidential information for a specific project. Authorization for any use and/or publication by 3rd parties of the report or any data, statements, conclusions or abstracts from or regarding the report and its drawings, through any form of print or electronic media, including without limitation, posting or reproductions of same on any website, is reserved by BGC, and is subject to BGC's prior written approval. Provided however, if the report is prepared for the purposes of inclusion in an application for a specific permit or other government process, as specifically set forth in the report, then the applicable regulatory, municipal, or other governmental authority may use the report only for the specific and identified purpose of the specific permit application or other government process as identified in the report. If the report or any portion or extracts thereof is/are issued in electronic format, the original copy of the report retained by BGC will be regarded as the only copy to be relied on for any purpose and will take precedence over any electronic copy of the report, or any portion or extracts thereof which may be used or published by others in accordance with the terms of this disclaimer.

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1.0 INTRODUCTION BCG Engineering Inc. (BGC) was retained by Trans Mountain Pipeline ULC (Trans Mountain) to complete a quantitative geohazard frequency assessment for the Trans Mountain Expansion Project, specifically the Line 2 delivery line as required by Condition 16 of OC-064. The physical geography along the TMEP route is varied and the pipeline route crosses multiple mountain ranges, high plateaus, and lowlands on route towards the Pacific Coast. These landscapes have been shaped by periods of tectonism, mountain uplift, glaciation, climate, and infrastructure development. In 2014, BGC undertook a quantitative frequency assessment of pipeline failure (defined as loss of containment) from geohazards along the proposed TMEP corridor where the Line 2 will be constructed (Trans Mountain 2014). The purpose of the assessment was to estimate at each geohazard site the frequency of loss of containment (FLoC) for the proposed pipeline and identify a sub-set of geohazard sites that require detailed investigations to support mitigation design. The results of the assessment were used by other project participants in support of broader hazard and risk assessment for the proposed pipeline. Later in 2015 and 2016, BGC updated the assessment based on the results of a review of additional LiDAR coverage along the alignment, site-specific fieldwork, revised estimates of input factors to estimate the FLoC, and the proposal of mitigations at geohazard locations that have a pre-mitigated FLoC values greater than 10-5. An assessment of the potential for geohazards to damage above ground facilities such as valves, pump stations, or terminals, is not included as part of this assessment. This assessment focuses on the occurrence of primary geohazards. Secondary or follow-up geohazards that could occur after the triggering of a primary geohazard, such as changes in stream courses by channel blockage by debris flows or landslides are not explicitly considered in this assessment. The results of this geohazard assessment are a snapshot in time and therefore can benefit from periodic review because of landscape changes (e.g. changes caused by construction, or development of new landslides or debris flows) and updates based on data collected along the alignment during operational monitoring.

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2.0 GEOHAZARD FREQUENCY ASSESSMENT METHODOLOGY

2.1. Risk Assessment Framework Over the last few decades, formalized risk management and risk assessment programs have become increasingly adopted by industry and regulators. The Canadian Standards Association (CSA) Z662 Standard for Oil and Gas Pipeline Systems, 2015 (CSA Z662) includes Annex B “Guidelines for risk assessment of pipelines” that provides guidance on the development and implementation of such programs. This annex is informative, non-mandatory, and provides a general risk assessment framework (Figure 1) for risk management. Risk assessment, in the framework presented in Figure 1, is divided into the two components; risk analysis and risk evaluation. Risk analysis consists of hazard identification, followed by the independent tasks of frequency analysis and consequence analysis. Risk estimation combines the results of the frequency and consequence analyses. Risk evaluation compares the significance of the estimated risks to societal, industry, and/or project specific risk thresholds.

2.2. Definitions and Key Concepts The definitions and methodology used in this risk assessment have been modified from those proposed in CSA Z662 and adopted on other large pipeline development projects in Canada, including the Mackenzie Gas Project (submitted to the National Energy Board in 2004) and the Northern Gateway Project (submitted to the National Energy Board in 2010).

2.2.1. Hazard As defined in CSA Z662, a hazard is a condition with the potential for causing an undesired consequence. A geohazard is a subset of natural hazards and is an event caused by “geomorphological, geological, or environmental processes, phenomena, and conditions that are potentially dangerous or pose a level of threat to human life, health, and property, or to the environment” (Komac & Zorn 2016). This assessment uses the term geohazard throughout.

2.2.2. Hazard Identification Hazard identification is the identification and characterization of credible geohazards that can reach the proposed pipeline and, as specified for the TMEP project, have the potential to result in a loss of pipeline containment. In this assessment, geohazards include hydrotechnical, geotechnical, and seismic hazards with geohazard category descriptions provided in Section 3.3.

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Figure 1. Risk Management Framework (from CSA Z662).

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2.2.3. Risk Risk is traditionally defined as the annual probability (P) of a hazard occurring multiplied by the consequences (C) of the hazard occurrence. It is commonly written as: Risk = P x C Risk can be expressed qualitatively (in words), semi-quantitatively (as words and numbers), or quantitatively (as a number, ideally as a financial cost). Probability is a number between 0 and 1 and consequences are often expressed in financial terms or as lives lost. Frequency and probability have subtly different meanings. Frequency is an estimate of the number of events per year, while probability is an estimate of the likelihood of one or more events per year. When the expected frequency of an event is low, frequency and probability take on similar numerical values. When the expected frequency of an event is high it can take on a numerical value greater than 1 (e.g., if more than one event per year is expected) while the probability of an event can never exceed 1. Risk can be defined as the annual frequency (or probability) of pipeline failure from a geohazard

(FPF) multiplied by the consequence of a pipeline failure. For this assessment, risk of pipeline failure from a geohazard at a specific location (i) along the pipeline can be represented by:

Risk = Annual Frequency of Pipeline Failure from a Geohazard (FPF) x Consequences of Pipeline Failure (C) or;

R(i) = FPF(i) x C(i) Pipeline “failure” can be defined several ways including loss of cover, coating damage, loss of pipeline service, or loss of containment ranging from pin-hole leaks to full ruptures. For this assessment, the TMEP project defines pipeline failure as a loss of containment (LoC) of any volume ranging from a leak to full rupture. The consequences of a LoC and the risk estimation components are not addressed in this report. This geohazard assessment is a frequency analysis and not a risk assessment.

2.3. Geohazard Frequency Analysis As per Figure 1, frequency analysis is the sub-component of risk analysis where the annual frequency of the pipeline failure is estimated. Estimating the annual frequency of the pipeline failure from a geohazard is facilitated by subdividing frequency into several factors that help differentiate and characterize each geohazard site. The factors include the annual frequency of geohazard occurrence, the frequency of spatial impact (the geohazard horizontally reaching and vertically touching the pipeline), vulnerability of the pipeline to the impacting geohazard, and the presence of mitigations applied to a specific location. The factors are described as the

Occurrence (I), Frequency (F), Horizontal Spatial (SH), Vertical Spatial (SV), Vulnerability (V), and Mitigation (M) factors, and can be expressed as:

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Annual Frequency of Loss of Containment (FLoC) from a Geohazard at a specific location (i) = Geohazard Occurrence (I) x Annual Frequency of Geohazard (F)

x Horizontal Spatial Probability of Geohazard Impacting the Pipeline (SH)

x Vertical Spatial Probability of the Geohazard Impacting the Pipeline (SV) x Vulnerability of the Pipeline to the Geohazard (V) x Mitigation Applied at the Geohazard Location (M) or;

FLoC(i) = I(i) x F(i) x SH(i) x SV(i) x V(i) x M(I(i),F(i),SH(i), SV(i),V(i)) Details for each factor are provided below. The subscript (i) represents a specific location along the proposed pipeline alignment.

2.3.1. Occurrence Factor (I)

The occurrence factor, I, characterizes the potential for a geohazard to occur. The factor is either 0 or 1, where 0 is used when the minimum number of contributing factors for geohazard occurrence are not present (i.e. geohazard occurrence is not credible), and 1 is used when geohazard occurrence is credible. For example, for rockfall, a value of 0 would be set at locations along the pipeline RoW where there are no recorded rockfall events, rock outcrops are shallower than 35° and greater than 100 meters slope distance upslope of the RoW, or rockfall initiation zones consisting of bedrock outcrops are greater than 500 meters slope distance upslope of the RoW.

2.3.2. Annual Frequency of Geohazard Occurrence (F)

The frequency term, F, is the number of observed (or predicted) geohazard events occurring at a specific location over a particular period. Frequency is typically expressed as the number of geohazard events of a defined magnitude per time interval and can exceed a value of 1 (e.g., 2 events per year), whereas probability is the likelihood of one or more geohazard events of a defined magnitude occurring per time interval and cannot exceed a value of 1 (e.g. 10% annual probability of occurrence). As indicated earlier, the word “frequency” is used in this analysis to conform with the precedent projects submitted to the NEB and terminology used in CSA Z662 guidance on risk assessments. Fortunately, for rare events (i.e. less than one event in one year) the annual frequency and annual probability take on similar values (the frequency will have a slightly higher value than the probability) and are interchangeable on a site-by-site basis. The presence or absence of historical geohazards in the area, the current activity of identified geohazards, and the presence or absence of contributing factors driving potential geohazards are all considered when estimating the annual frequency of a geohazard.

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2.3.3. Horizontal Spatial Probability of Impact (SH)

The horizontal probability of impact, SH, is the conditional probability that the geohazard will, after initiation, reach the RoW and cross the centerline of the pipeline at the RoW ground surface. This spatial probability is dependent on the geohazard type (mechanism), magnitude, intensity, and the conditions along the travel path from the initiation zone of the geohazard to the centerline of the pipeline. For example, for many of the landslide hazards, the horizontal spatial probability depends on the distance between where the landslide starts and the pipeline centerline, the mobility of the landslide, its ability to overcome natural barriers along the landslide trajectory such as trees and/or topographic barriers between the initiation zone and the pipeline centerline. For hydrotechnical hazards, the spatial probability depends, in part, on the horizontal distance from the river’s edge to the location of the proposed pipeline centerline.

2.3.4. Vertical Spatial Probability of Impact (SV)

The vertical spatial probability of impact, SV, is the conditional probability that a geohazard will, after reaching the pipeline centerline, breach the proposed pipeline depth of cover and come into contact with the pipeline. This spatial probability is dependent on the geohazard type (mechanism), magnitude, intensity, and the type and condition of the pipeline cover. For example, for debris flows or most hydrotechnical hazards, vertical spatial probability of impact depends on whether the geohazard can scour through the pipeline depth of cover. For deep-seated landslides, it depends on whether the pipeline is buried deeper than the base of the landslide. The vertical spatial probability of impact from rockfall depends to the rockfall magnitude, intensity, and the characteristics and thickness of pipeline cover.

2.3.5. Vulnerability (V)

Vulnerability, V, is a conditional probability that describes the pipeline’s ability to withstand damage from a geohazard, given that the geohazard has occurred, reached the centerline, and has come into contact with the pipe. The vulnerability of a pipeline depends on the mechanism, magnitude, and intensity of the geohazard, the direction of geohazard loads on the pipeline, and the properties of the pipeline and operations including coating type, wall thickness, diameter, steel grade, and operating pressure.

2.3.6. Mitigation (M) Mitigations can be applied to the geohazard and/or to the pipeline to help defend the pipeline from geohazards and reduce the FLoC. Sections of the pipeline that exceed the project’s FLoC threshold are candidates for additional geohazard and/or pipeline mitigation. The proposed mitigation for the geohazard and/or the pipeline reduces the FLoC at each geohazard site by

reducing one or more of the FLoC factors of I(i), F(i), SH(i), SV(i), and V(i). The mitigation factor (M)

for each of I(i), F(i), SH(i), SV(i), and V(i) is a value that ranges between 0 and 1 and represents the proportional reduction in potential for loss of containment. At some geohazard sites where multiple types of mitigation are proposed, a lower limit was set for the cumulative mitigation value

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to prevent unrealistic reductions in the overall FLoC that would be calculated by multiplying several mitigation factor scores together.

2.3.7. FLoC Uncertainty Uncertainty in the FLoC score, or its factors, is not explicitly stated; however, the uncertainty is implicit in the approach to assigning a single value to each factor. For example, the geohazard frequency factor may be assigned using several techniques including: • An order-of-magnitude approach, in which an annual frequency is estimated to be on-the- order of, 1, 0.1, or 0.001 events per year, while the specific frequency is not known. This approach is used where uncertainty is highest, and is recognized in the Canadian Technical Guidelines and Best Practices (Porter & Morgenstern 2013) related to landslides as a necessary approach in some cases. • Convention for some geohazards to make similar, but slightly higher fidelity estimates of frequency that are expressed in terms of a range of return intervals (1/frequency), e.g. 1- 10 years, 10-30 year, 30-100 years, 100-300 years, etc. A single average value is used to represent the range of each return interval. • A direct estimate of the frequency through recognizing the number of past events over a period of which they occurred. The number of event can be estimated by field or terrain observations, convention, or judgement. These estimates of the frequency may have higher precision, but still contain significant uncertainty. • In some cases, a specific frequency that represents a design basis or acceptance threshold, and is set as constant. For example, designs that protect against pipeline exposure from a 200-year return period flooding event. The magnitude of such an event is estimated from field or terrain observations, historical data, extreme value statistical methods, and judgement. The remaining factors in the FLoC equation are defined as a probability, such that the numerical value is between 0 and 1 and represents the proportion of all events that would be expected to reach the buried pipeline or cause a loss of containment. While high-precision analytical estimates for some of these factors may be possible in highly controlled conditions typical geohazard scenarios are highly uncertain and precise analytical solutions are not available. The precision for each of the estimated factors in this assessment reflects the underlying uncertainty in each of the factors, i.e. typical precision may be in steps of 0.1 or in some cases 0.5. In many cases, the uncertainty in the estimated factor may exceed the precision of the values that are assigned. In this case, the most likely value is selected with the recognition that others values are possible. The multiplicative approach to combining these factors into a single FLoC score is robust, but leads to a propagation and multiplication of factor uncertainty into the FLoC score. The result of this multiplicative approach is there is generally an increase in the range of possible outcomes, although typically the FLoC reported for each site represents the most likely estimate. Since each of the FLoC factors are typically not a continuous distribution, neither is the range of possible FLoC scores. As a result, the comparison between the FLoC score and a pre-defined threshold

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should consider that even if the FLoC score is above or below the threshold, one or more of the many possible scores may be at or on the other side of the threshold. More importantly, FLoC scores close to the threshold (i.e. closer than the uncertainty in the least precise factor) are fundamentally indistinguishable from the threshold, and it may be justified to treat them as such.

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3.0 TMEP GEOHAZARD FREQUENCY ASSESSMENT Trans Mountain has adopted a risk-based design process that combines estimates of annual pipeline failure frequency and pipeline failure consequence to estimate the risks of pipeline failure from various hazards along the pipeline. Towards supporting that overall risk assessment, credible geohazards along the pipeline were identified and the FLoC has been estimated at each geohazard site following the framework outline in Section 2.0. As described in Section 2.0, the frequency analysis values can be expressed qualitatively (descriptive terms) or quantitatively (numerical values) (CSA Z662 ). The factors used to estimate the FLoC have been estimated using a combination of empirical analyses, deterministic assessments, and expert judgement, where applicable, for each hazard type at each location.

3.1. Geographic Extent of Assessment This assessment was conducted on the TMEP SSEID 005 Route Corridor. To determine the spatial relationship between individual geohazards and the pipeline, the SSEID 005 pipeline route was used as a proxy for the proposed centerline alignment. It should be recognized that this pipeline route does not represent the final construction centerline as the pipeline alignment may be modified in the period leading to and during construction. Despite the potential for changes to the alignment leading to and during construction, a centerline is necessary to perform the requisite calculations for the geohazard frequency analysis and risk assessment. In addition to geohazards identified within the corridor, the area assessed included all slopes above the pipeline route on both sides of valleys where geohazards could originate, and areas below the corridor where retrogression of a geohazard up the slope could potentially impact the pipeline. This extension of the analysis area beyond the SSEID 005 corridor was dependent upon the geohazard and the potential mobility of the hazard. For slope movement hazards, the analysis area was typically extended to the top of the height of land in valleys. For hydrotechnical hazards, the analysis area was typically confined to the river floodplain for hazards such as avulsion and lateral erosion, while for outburst floods, possible sources up to 10+ kilometers away in alpine valleys were also considered. Known reference points along the existing Trans Mountain pipeline system are commonly referred to as a Kilometer Post or “KP”. KP 0.0 is located at the Edmonton Terminal where the existing Trans Mountain system originates. KPs are approximately 1 km apart and are primarily used to describe features along the pipeline for operations and maintenance purposes. KPs have been used in this assessment to delineate features along the reference line within the proposed TMEP corridor.

3.2. Data Sources and Assessments Used in the Updated Geohazard Analysis The updated geohazard assessment is based on additional data sources and assessments obtained since 2014. Appendix A contains the data sources used to assess each geohazard type and the list below summarizes the data sources and assessments used:

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a. Aerial photographs. The most recent available aerial photographs were selected with a scale of 1:15,000 or 1:20,000 for each section of the alignment. Where multiple sets of aerial photographs were available at the scales indicated above, the most recent aerial photographs were preferentially chosen as they are typically higher quality than historical aerial photographs. Historical aerial photographs were also examined for specific locations, such as watercourse crossings, where they provide useful information on changes in channel planform or other geohazard activity through time. b. Immersive video recording. Immersive video, conducted using a helicopter and live flight recording along the Trans Mountain corridor in 2012, was reviewed. The flight video provided the ability to review the recent imagery from multiple directions. c. Updated terrain mapping. The original terrain stability and geohazard mapping along the pipeline corridor was updated in 2015 and 2016 based on additional surficial geology mapping and subsurface borehole data. d. LiDAR data. Light Detection and Ranging (LiDAR) digital elevation data that completely covered the pipeline corridor in BC and Alberta. e. Google EarthTM satellite imagery. The review of the aerial photographs was supplemented by comparison against Google EarthTM satellite imagery. f. Historical records. Geohazard records were obtained from Kinder Morgan Canada Inc.’s (KMC) Natural Hazard Management Program for the existing Trans Mountain corridor. This program includes site specific hazard and mitigation information from annual field inspections conducted by KMC, BGC, and other groups since 1998 at specific geohazard locations along the existing Trans Mountain corridor. g. Pipeline design and pipe parameters. The location of the watercourse and overland HDD’s and pipe parameters such as the pipe wall thickness and pipe coating were reviewed in 2016 and incorporated in the geohazard frequency assessment. h. Debris flows and debris floods. Debris-flow and debris-flood assessments were completed for the pipeline corridor in 2015 and 2016. A desktop inventory was constructed that identified debris flow channels and fans that cross the pipeline corridor. The identified channels and fans were reviewed in the field to refine estimates of the input parameters for the FLoC analysis. i. Hydrotechnical hazards. Assessments of hydrotechnical hazards at watercourse crossings were completed along the alignment. The detailed assessments consisted of a desktop study including flood frequencies, review of the LiDAR dataset, satellite imagery, survey data, and historical aerial photographs. Field investigations were completed to collect site specific information. j. Rock and soil slope geohazards. Site specific assessments of rock and soil slope geohazards were completed in 2015 and 2016 along the pipeline corridor. The study included desktop review of the LiDAR data and field assessments at select sites to refine estimates of the input parameters for the FLoC analysis for the rock and soil slope geohazards along the proposed pipeline corridor. k. Vulnerability assessments. Several parametric assessments completed by CFER Technologies and Universal Pegasus International (UPI) were used to guide the pipe vulnerability values used in the FLoC analysis.

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3.3. Geohazards Assessed Twelve geohazard types were evaluated for this analysis. They represent credible geohazards that, under certain circumstances, are reasonably capable of causing a loss of pipeline containment. These geohazards fall into four general classes (Rock Slope, Soil Slope, Hydrotechnical, and Seismic), and are listed below in Table 1. Further detailed descriptions, including ranking guidelines for some geohazards, are provided in Appendix A. Seismic hazards were assessed along the corridor and are covered in a separate document and not repeated herein (Trans Mountain 2017).

Table 1. Summary of assessed geohazards. Geohazard Geohazard Description Class Category Fragments of rock that detach from a steep rock outcrop and Rockfall travel downslope independently with a free falling, bouncing, or rolling motion. A large rock mass (~1,000 m3 to 100,000 m3 total volume of Extremely rapid rock mass) releases from a steep rock outcrop along one or Rock Slope rockslides more discontinuities and travels downslope extremely rapidly Geohazards (>3 m/s velocity). A large rock mass (~0.1M m3 to >100M m3 total volume of rock mass) releases from a steep rock outcrop along one or more Extremely rapid discontinuities and travels downslope extremely rapidly with rock avalanches high mobility (flow-like movement) with runout distances that can exceed several kilometers. A shallow layer of weak soil or weathered rock overlying more Debris competent soil or bedrock that detaches and slides rapidly slides/avalanches Soil Slope down a steep slope. Geohazards A slow-moving mass of soil or very weak rock that moves Earth landslides primarily by sliding on a basal shear surface, potentially accompanied by internal deformation. An extremely rapid down slope movement of a saturated Debris flows mixture of soils, rock, organic debris and water within an established channel. A very rapid surging flow of water within an established Debris floods channel that contains a high concentration of suspended and bedload sediment. Hydrotechnical Avulsion is the process when a stream forms a new channel Hazards Avulsion outside of the original channel boundaries that incises into the floodplain, most often during a high flow event. The removal of material from a channel by the erosive action Scour of water resulting in localised channel bed lowering. The removal of soil and rock material from a stream bank by Lateral erosion the erosive action of water resulting in the lateral migration of the bank.

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Geohazard Geohazard Description Class Category A sudden, high volume and flow flood surge caused by the Outburst-type break of a dam and the subsequent release of the impounded floods water. Liquefaction and Permanent ground displacement associated with seismic Seismic Permanent liquefaction is the movement of material on sloping ground or Geohazards Ground close to river bank free face slopes as a result of seismic Displacement liquefaction.

3.4. Other Geohazards Additional geohazards that are not specifically evaluated using the geohazard assessment process include karst, acid rock drainage, and tsunamis. These geohazards are briefly discussed below.

3.4.1. Karst Karst is the downward deformation of ground surface, either as slow deflation or rapid collapse, due to the presence of void space in the underlying bedrock created by dissolution of carbonate minerals or evaporites. Terrain that potentially contains karst was identified along some sections of the corridor based on large scale reconnaissance level mapping by the BC Ministry of Forests (MOFR 1999). Based on the BC Ministry of Forests mapping, the areas where the pipeline alignment runs through regions that potentially contain karst include: • KP 503.2 to 528.6, • KP 739.3 to 746.3, • KP 755.8 to 757.3, • KP 818.1 to 820.8, • KP 1071.6 to 1112.2. LiDAR was reviewed and there was no indication of subsidence in the direct vicinity of the corridor or along the route. In addition, there has been no history of the development of large scale voids or subsidence within the existing Trans Mountain corridor. However, should subsidence or collapse occur through the formation of a sinkhole, the vulnerability of the pipeline to loss of containment is considered low as the pipeline will be capable of remaining unsupported and spanning greater than 10’s of meters in length under its own weight without failure.

3.4.2. Acid Rock Drainage and Metal Leaching Rock and soil that can generate acid as a result of the oxidation of iron-bearing sulphur minerals

such as Pyrite (FeS2), Pyrrhotite (FeS), Chalcopyrite (CuFeS2), etc, and those than can leach harmful naturally occurring metals into the environment upon contact with surface- or groundwater have been initially assessed as part of a preliminary Acid Rock Drainage and Metal Leaching Assessment filed in the Application (Volume 5C). The potential for acid rock drainage to cause a catastrophic loss of containment is considered low due to the protective coatings that will be

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applied to the pipeline. External corrosion is not addressed in this geohazards assessment and is being addressed as part of the overall risk assessment.

3.4.3. Tsunami The potential for seismic tsunami generation has been identified along the West Coast of BC. This hazard has the potential to extend into English Bay and the Westridge Terminal located near Burnaby, BC. The estimated credible tsunami run-up potential in the vicinity of the Westridge Terminal is less than 2 m elevation above sea level (Clague et. al. 2006; Clague & Orwin 2005). The potential for loss of containment from a tsunami for the buried pipeline is considered very low given the burial depth and elevation of the pipeline above sea level. The tsunami run-up potential will be considered in the design of the Westridge Terminal, and is not specifically addressed in this assessment.

3.5. FLoC Threshold A FLoC threshold has been set by Tthe NEB’s conditions for approval of the project (NEB 2016). Condition 16 of OC-064 requires: Trans Mountain must file with the NEB, at least 6 months prior to commencing construction, an updated Quantitative Geohazard Frequency Assessment for the Line 2 and delivery pipeline segments that contains a re-assessment of the Frequency of Loss of Containment (FLoC) values based on the results of site-specific field assessments and any required mitigation as determined in the detailed engineering and design process. Trans Mountain must provide in the assessment a plan to manage and mitigate geohazards at any location where the FLoC is greater than 10-5 events per year to reduce the level of risk to as low as reasonably practicable (ALARP), including a detailed explanation of how ALARP level has been attained at each location. A value of 10-5 events per year means a 1 in 100,000 chance per year of a loss of containment event occurring. The FLoC threshold allows the identification of sites where additional hazard mitigation or risk management actions may be warranted. The NEB has indicated that Trans Mountain must provide a plan to manage and mitigate geohazard locations that have a FLoC value greater than 10-5 events per year to reduce the level of risk to as low as reasonably practicable (ALARP). The FLoC value of 10-5 is hereinafter referred to as the “threshold” value for the purposes of this report. As outlined in Section 2.2.3 and illustrated in Figure 1, this assessment is the hazard frequency analysis component of a risk analysis that estimates the FLoC associated with identified geohazards at specific sites. Consequences and risk associated with the potential loss of containment at these sites are not evaluated in this assessment, but rather are being assessed as part of other components of the project, and are described in NEB Condition 15 and 17. This assessment provides a plan to manage and mitigate geohazards that have a pre-mitigated FLoC value greater than 10-5 through a reduction of the hazard frequency component of risk, and

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explains how As-Low-As-Reasonably-Practicable (ALARP) has been achieved for sites where the mitigated FLoC will exceed 10-5. ALARP, in terms of the frequency of loss of containment as opposed to risk, involves weighing the reduction in the predicted loss of containment frequency against the mitigation implemented to further reduce it. As noted in Section 6.1.3 and 6.1.4 in the Board’s May 2016 report, the ALARP principle dictates that mitigation should be considered until a point of diminishing returns has been reached with respect to the implementation of further resources. Once it has been established that reduction of the predicted FLoC in one area is not sensitive to further implementation of hazard-mitigation measures, resources are more appropriately directed at reducing the frequency in other areas.

3.6. Geohazard Frequency Assessment Pre-mitigated FLoC values were estimated assuming standard pipeline design and construction techniques would be employed. Results from the pre-mitigated analysis were then compared to the FLoC threshold set by the NEB. Atypical mitigations, defined as mitigation designs that would not normally be employed in standard pipeline design, were considered and applied where the pre-mitigated FLoC was greater than 10-5.

3.6.1. Mitigation Assessment Mitigations at specific geohazard sites were selected by considering the pipeline design and construction standard of practice and comparing the relative effort of implementation to the estimated reduction in the FLoC. Depending on the type of geohazard, potential mitigations could consist of increasing the burial depth, installing heavier wall pipe, or re-routing the pipeline alignment to avoid the geohazard. For some sites, multiple mitigation designs were proposed to reduce the FLoC to below the 10-5 threshold. Trans Mountain reviewed and evaluated the proposed mitigations to ensure that they were appropriate in the planning, design, construction, and operation phases of the project. If the proposed mitigation designs were not acceptable, the mitigation selection process was repeated until a suitable mitigation was selected for the specific site. Figure 2 illustrates the iterative mitigation selection process for all geohazard types. After applying the mitigation designs, some sites had estimated FLoC values that were still greater than the 10-5 threshold. Additional mitigation designs to further reduce the FLoC were not applied at these sites because they would either result in a design that greatly exceeds the typical standard of practice, were not considered practical, would result in additional environmental impact, or would only result in a marginal reduction in the FLoC.

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Figure 2. Mitigation assessment flow chart.

Note: Potential mitigations provided in the flow chart are not applicable to all geohazard types and do not represent all types of mitigations. Appendix A contains the potential mitigations for each geohazard type.

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4.0 RESULTS Appendix B and Appendix C contain the results of the geohazard analysis listed by KP and by geohazard type, respectively. The data in each appendix provides the type, location, and length of the geohazard along the pipeline route, and the assigned occurrence, frequency, horizontal and vertical spatial, vulnerability, and the mitigation values. Appendix D provides further details on the factors for individual geohazard sites with pre-mitigated FLoC values greater than 1 x 10-5 events per year. Table 2 summarizes the results for the pre- and post-mitigated geohazard analysis with Table 3 and Table 4 presenting a detailed summary for post-mitigated FLoC values greater than 1 x 10-5. A total of 1,569 credible geohazards segments were identified along the alignment. Of the 1,569 segments, 220 (14.0%) have pre-mitigated FLoC values greater than 1 x 10-5. The application of mitigation designs in the post-mitigated assessment has reduced the number of segments that are greater than 1 x 10-5 to 40 (2.6%). Of the 40 sites that remain greater than 10-5, 24 are only slightly above the threshold with FLoC values between 2 x 10-5 and 1 x 10-5. Given the uncertainty in the analysis, as discussed in Section 2.3.7, such sites could be considered to have equivalent values as those scoring at 10-5. Table 5 contains a summary of geohazard reduction strategies to reduce the geohazard to ALARP for segments that have post-mitigated FLoC scores greater than 10-5. Figure 3 illustrates the pre-mitigated and post-mitigated distribution of geohazard segments along the proposed alignment. Most the geohazards are unevenly distributed along the alignment, but with several geohazard segments concentrating around the central and western sections of the alignment.

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Table 2. Summary of the pre- and post-mitigated geohazard results. Pre-Mitigated Post-Mitigated Frequency of

Loss of Containment Total Length of Total Length of (Events/Year) Number of % of Total Segment Number of % of Total Segment Segments (km) Segments (km) >10-1 0 0 0 0 0 0 10-1 to >10-2 0 0 0 0 0 0 10-2 to >10-3 2 0.1 0.9 0 0 0 10-3 to >10-4 25 1.6 17.1 1 0.1 0.6 10-4 to >10-5 193 12.3 83.6 39 2.5 45.6 10-5 to >10-6 407 25.9 152.3 475 30.3 180.8 10-6 to >10-7 399 25.4 112.5 395 25.2 123.0 <10-7 543 34.6 60.8 659 42.0 77.2 Total 1,569 100 427.2 1,569 100 427.2

Table 3. Detailed summary of post-mitigated geohazard FLoC greater than 10-5 events per year. Pre-Mitigated Post-Mitigated Frequency of

Loss of Containment Total Length of Total Length of (Events/Year) Number of % of Total Segment Number of % of Total Segment Segments (km) Segments (km) 10-2 to >10-3 2 0.9 0.9 0 0 0 10-3 to >10-4 25 11.4 17.1 1 2.5 0.6 10-4 to > 2x10-5 115 52.3 57.9 15 37.5 20.5 2x10-5 to >10-5 78 35.4 25.7 24 60.0 25.1 Total 220 100 101.6 40 100 46.2

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Table 4. Summary of post mitigated geohazard FLoC greater than 10-5 events per year by geohazard class and category. Rock Soil Hydrotechnical Hazards Geohazards Geohazards

Frequency of

Loss of Containment (Events/Year) Landslides Scour Rockfall Flooding Avulsion Rock Slide Debris Flow Debris Debris Slide Debris Flood Debris Encroachment Lateral Erosion Outburst Floods Outburst Earth Rock Avalanches

10-2 to >10-3 0 0 0 0 0 0 0 0 0 0 0 0 0 10-3 to >10-4 0 1 0 0 0 0 0 0 0 0 0 0 0 10-4 to >2x10-5 0 1 9 0 0 1 0 3 0 1 0 0 0 2x10-5 to >10-5 4 4 8 1 0 0 1 2 0 4 0 0 0 Total 4 6 17 1 0 1 1 5 0 5 0 0 0

Pre-mitigated 10⁻¹ to >10⁻² 10⁻² to >10⁻³ 10⁻³ to >10⁻⁴ 10⁻⁴ to >2x10⁻⁵ 2x10⁻⁵ to >10⁻⁵

Post-mitigated 10⁻¹ to >10⁻² 10⁻² to >10⁻³ 10⁻³ to >10⁻⁴ 10⁻⁴ to >2x10⁻⁵ 2x10⁻⁵ to >10⁻⁵ 60 80

70 50 60 40 50

30 40 Count Count 30 20 20 10 10

0 0

KP Figure 3. Number of pre- and post-mitigated geohazards along the proposed TMEP alignment with FLoC > 10-5 events per year.

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5.0 CLOSURE We trust the above satisfies your requirements. Should you have any questions or comments, please do not hesitate to contact us.

Yours sincerely,

BGC ENGINEERING INC. per:

Michael Beaupre, M.Eng., P.Eng., P.Geo. Dr. Dave Gauthier, P.Eng., P.Geo. Geological Engineer Senior Geological Engineer

Dr. Joseph Gartner, EIT Dr. Pascal Szeftel Debris Flow Specialist Water Resources Specialist

Reviewed by:

Dr. Alex Baumgard, P.Eng., P.Geo. Mark Leir, M.A.Sc., P.Eng., P.Geo. Principal Geotechnical Engineer Principal Geological Engineer

MB/AB/ML/mjp/al

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REFERENCES

British Columbia Ministry of Environment, Lands and Parks (BC MOE). 1999. Guidelines for Managements of Flood Protection Works in British Columbia. Public Safety Section, Water Management Branch, March 1999. Alberta Environment and Sustainable Resource Development (AESRD). 2013. Code of Practice for Pipelines and Telecommunication Lines Crossing a Water Body. Alberta Government, June 24, 2013. Canadian Standards Association. 2015. CSA Standards – Oil and Gas Pipeline Systems Z662. Canadian Standards Association, Ontario, Canada. Z662 7th Edition. Published January 1, 2015. Clague, J. & Evans, S. 2000. A review of catastrophic drainage of moraine-dammed lakes in British Columbia. Quaternary Science Reviews. Vol. 19. pp. 1763-1783. Clague, J. & Evans, S. 1994. Bulletin 464: Formation and Failure of Natural Dams in the Canadian Cordillera. Geological Survey of Canada. Natural Resources Canada, Vancouver, pp. 35. Clague, J., Yorath, C.J.J., Franklin, R., & Turner, R.J.W. 2006. Tsunami hazard zones for southwestern British Columbia. At risk. Earthquakes and tsunamis on the west coast, Tricouni Press, Vancouver. Clague, J. & Orwin, J. 2005. Tsunami Hazard to North and West Vancouver, British Columbia. Presented to: North Shore Emergency Planning Office. Corominas, J. 1996. The angle of reach as a mobility index for small and large landslides. Can Geotech. J. Vol. 33, pp. 260 – 271. Dooley, C., Prestie, Z., Ferris, G., Fitch, M., and Zhang, H. 2014. Approaches for evaluating the vulnerability of pipelines at water crossings. Proceedings of the 10th International Pipeline Conference. September 29 – October 3, 2014, Calgary, Alberta, Canada. Evans, S. & Hungr, O. 1993. The assessment of rockfall hazard at the base of talus slope. Can. Geotech. J. Vol. 30, pp. 620 – 636. Komac, B. & Zorn, M. 2016. Encyclopedia of Natural Hazards ed. P. Bobrowsky. Springer Netherlands. pp. 387. Ferris, G., Newton, S., Ho, M., Eichhorn, G., Bear, D. 2015. Flood Monitoring for Buried Pipeline Watercourse Crossings. Technical Paper at the Rio Pipeline Conference & Exposition. September 22-24, 2015, Rio de Janeiro, Brazil. GeoBase. 2010. National Hydro Network. Natural Resources Canada – Earth Sciences Sector. Sherbrooke, Canada. Holm, K. & Jakob, M. 2009. Long rockfall runout, Pascua Lama, Chile. Can. Geotech. J. Vol. 46, pp. 225 – 230.

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McDougall, S., McKinnon, M., & Hungr, O. 2012. Developments in landslide runout prediction. Landslides Types, Mechanisms and Modeling ed. by J. Clague & D. Stead. Cambridge University Press, pp. 187 – 195. McKillop, R. & Clague, J. 2006. A procedure for making objective preliminary assessments of outburst flood hazard from moraine-dammed lakes in southwestern British Columbia. Nat Hazards. Vol. 41, Issue 1, pp. 131 – 157. Ministry of Forests and Range (MOFR). 1999. Karst Potential Maps for B.C. Forest Practices Branch. Mitchell, R. & Markell, A. 1973. Flowsliding in Sensitive Soils. Can. Geotech. J. Vol. 11, pp.11 – 33. National Energy Board (NEB). 2016. National Energy Board Report – Trans Mountain Expansion Project, May 2016. Report # OH-001-2014 (Filing ID A77045). Pichler, B., Hellmich, Ch., and Mang, H.A. 2005. Impact of rocks onto gravel Design and evaluation of experiments. International Journal of Impact Engineering. Vol. 31, pp. 559 – 578. Pierson, L.A., Gullixson, F.C., & Chassie, R.G. 2001. Rockfall Catchment Area Design Guideline Final Report. Research Group Oregon Department of Transportation and Federal Highway Administration. Report No. FHWA-OR-RD-02-04m. December 2001, pp. 91. Porter, M. & Morgenstern, N. 2013. Landslide Risk Evaluation. Canadian Technical Guidelines and Best Practices related to Landslides: a national initiative for loss reduction. Geological Survey of Canada, Open File 7312. pp. 21. Trans Mountain Pipeline ULC. 2013a. Trans Mountain Expansion Project Application to the National Energy Board. Volume 4A – Appendix H: Terrain Mapping and Geohazard Inventory Report. Trans Mountain Pipeline ULC. 2013b. Trans Mountain Expansion Project Application to the National Energy Board. Volume 5C – Acid Rock Drainage and Metal Leaching Assessment. Trans Mountain Pipeline ULC. 2014. Trans Mountain Expansion Project – Quantitative Geohazard Frequency Assessment. Attachment B of “Preliminary Risk Results for TMEP Line 2 and New Delivery Lines”, files as part of NEB Technical Update No.1 and Consultation Update No.2, August 1, 2014. Trans Mountain Pipeline ULC. 2015. Trans Mountain Expansion Project – Seismic Hazard Update – Final. Appendix D – Lower Mainland and Fraser Valley Fault Assessment Report. Filed with NEB as documented filing ID A4K0Z3. Trans Mountain Pipeline ULC. 2017. Trans Mountain Expansion Project – Seismic Liquefaction and Lateral Spreading Assessment Update. (To be submitted in 2017)

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TABLE 5 SUMMARY OF GEOHAZARD REDUCTION STRATEGIES FOR GEOHAZARD SEGMENTS WITH POST-MITIGATED FLOC GREATER THAN 10-5

Trans Mountain Attachment 1 Condition 16 Final.docx BGC ENGINEERING INC. Trans Mountain Pipeline ULC, Trans Mountain Expansion Project February 27, 2017 Quantitative Geohazard Frequency Assessment – Post Mitigation Project No.: 0095150-22

Table 5. Summary of geohazard reduction strategies for geohazard segments with post-mitigated FLoC greater than 10-5. Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC

489.16 Rock Klapperhorn One rock avalanche deposit and several potential sources areas were identified in the 2.6x10-5 Avalanche Mountain region between Valemount to Hargraves. These source areas and rock avalanche deposit – cover an approximately 7 km long section of the alignment. It is unlikely that any practical 491.73 mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

495.78 Rock Mount Terry Fox One rock avalanche deposit and several potential sources areas were identified in the 2.2x10-5 Avalanche West Slope region between Valemount to Hargraves. These source areas and rock avalanche deposit – cover an approximately 7 km long section of the alignment. It is unlikely that any practical 497.92 mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

518.13 Lateral Swift Creek Setback of overbend and sag bends have been designed to accommodate floods up to the 1.2x10-5 Erosion 200-year event without exposure of the pipeline at a distance of 10 m back from the banks, – (Bank and the crossing has been designed with heavy wall (17.2 mm) and the use of concrete 518.17 Erosion) coating on the pipe. Additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

547.99 Lateral Albreda River Setback of overbend and sag bends have been designed to accommodate floods up to the 1.2x10-5 Erosion 200-year event without exposure of the pipeline at setback distance of 25 m on the right – (Bank bank and 30 m on the left bank, and the crossing has been designed with heavy wall (17.2 548.05 Erosion) mm) and the use of concrete coating on the pipe. Additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC

563.66 Lateral Dominion Creek Setback of overbend and sag bends have been designed to accommodate floods up to the 3.9x10-5 Erosion 200-year event without exposure of the pipeline at a setback distance of 10 m on the right – (Bank bank and 30 m on the left bank, and the crossing has been designed with heavy wall (17.2 563.71 Erosion) mm) and the use of concrete coating on the pipe. Additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

563.66 Scour Dominion Creek An additional 0.4 m of increased depth of cover will be added to the depth of cover required 3.0x10-5 to prevent exposure up to the 200-year flood event (to attain a total depth of cover of 2 m), – and the crossing has been designed with heavy wall (17.2 mm) and the use of concrete 563.71 coating on the pipe. Given local site conditions, additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

581.78 Rock Thunder River Three to five rock avalanche deposit and several potential sources areas were identified in 1.3x10-5 Avalanche the region between Valemount to Blue River. These source areas and rock avalanche – 586.5 deposit cover an approximately 44 km long section of the alignment. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

588.81 Debris Miledge Creek The pipeline crosses a debris flood fan with visible boulder deposits that are mossed over. 1.3x10-5 Flood Fan Mitigations including 2 m depth of cover and increasing the pipeline wall thickness to heavy – wall (17.2 mm) results in a reduction in the in the pre-mitigated FLoC. Given the local site 588.98 conditions, additional mitigations to further reduce the FLoC are not feasible and/or results in a marginal reduction in FLoC.

639.08 Rockfall Groundhog A sub vertical bedrock outcrop is located upslope of the alignment with rockfall talus present 1.5x10-5 Mountain at the proposed alignment. The talus is vegetated with second growth deciduous trees and – a number of the boulders are covered with moss. Several approximately 1 m diameter 639.19 rockfall observed across the proposed alignment. The recommended mitigation of increasing the pipeline wall thickness to extra heavy wall (19 mm) and increasing the depth of cover overtop of the pipeline to 2.3 m with replacement of the talus grade if possible

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC results in a significant reduction in the pre-mitigated FLoC. Given the limited space adjacent to the RoW, and the inaccessible rockfall sources, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1008.01 Lateral Boston Bar Setback of overbend and sag bends have been designed to accommodate floods up to the 1.2x10-5 Erosion Creek 200-year event without exposure of the pipeline at a distance of 15 m back from the banks, – (Bank and the crossing has been designed with extra heavy wall (17.2 mm) and the use of 1008.07 Erosion) concrete coating on the pipe. Additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

1012.34 Rock Old Coquihalla In the region between the Coquihalla Summit and Hope, there is evidence of approximately 1.1x10-5 Avalanche Road five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1013.94 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1013.16 Rockfall Old Coquihalla The pipeline traverses through a talus slope with evidence of recent rockfall activity. The 1.5x10-5 Road West talus slope has been partially logged and initial pioneering species partially vegetate the – Slopes slope. Sections of the talus slope that have not been logged are vegetated with mature 1013.94 conifer trees. Some of the talus blocks are covered with moss. The recommended mitigation of increasing the pipeline wall thickness to extra heavy wall (19 mm) and increasing the depth of cover overtop of the pipeline to 1.8 m results in a significant reduction in the pre-mitigated FLoC. Given the limited space adjacent to the RoW, and the inaccessible rockfall sources, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1016.82 Rock Ladner Creek In the region between the Coquihalla Summit and Hope, there is evidence of approximately 2.0x10-5 Avalanche Slopes five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1019.96 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC

1018.87 Scour Coquihalla River An additional 1.0 m of increased depth of cover will be added to the depth of cover required 1.2x10-5 to prevent exposure up to the 200-year flood event (to attain a total depth of cover of 3 m), – and the crossing has been designed with extra heavy wall (19 mm) and the use of concrete 1018.94 coating on the pipe. Subsurface investigation and local experience indicate that this site is not feasible geotechnically for HDD. Given local site conditions, additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

1020.92 Rock Mount Snider In the region between the Coquihalla Summit and Hope, there is evidence of approximately 1.7x10-5 Avalanche North five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1023.63 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1020.92 Earth Mount Snider The pipeline alignment is located along the toe of a very large relic earth flow. The earth 1.2x10-5 Landslide flow appears abandoned, with mature trees along the toe of the slope growing vertically – (indicating no recent movement). The recommended mitigation of increasing the pipeline 1023.63 wall thickness to extra heavy wall (19 mm), using a loose/compliant trench backfill, and site specific stabilization measures results in a significant reduction in the pre-mitigated FLoC. Given local site conditions, additional mitigations to further reduce the FLoC is not practical, and/or results in a marginal reduction in the FLoC.

1022.91 Rockfall Mount Snider The alignment traverses the toe of a steep slope with evidence of rockfall activity. Rock 1.5x10-5 outcrops are located upslope of the pipeline alignment. The slope is vegetated with mature – coniferous trees and contains several exposed rock outcrops. What has been inferred as 1023.04 impact scars were observed on several mature trees located mid slope. Moss covered boulders are located at the toe of the slope. The recommended mitigation of increasing the pipeline wall thickness to extra heavy wall (19 mm) and increasing the depth of cover overtop of the pipeline to 1.8 m results in a significant reduction in the pre-mitigated FLoC. Given the limited space adjacent to the RoW, and the inaccessible rockfall sources, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC

1024.39 Rock Emancipation In the region between the Coquihalla Summit and Hope, there is evidence of approximately 5.9x10-5 Avalanche Mountain five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1026.71 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1025.82 Scour Coquihalla River An additional 0.5 m of increased depth of cover will be added to the depth of cover required 4.0x10-5 to prevent exposure up to the 200-year flood event (to attain a total depth of cover of 3 m), – and the crossing has been designed with extra heavy wall (19 mm) and the use of concrete 1025.9 coating on the pipe. Subsurface investigation and local experience indicate that this site is not feasible geotechnically for HDD. Given local site conditions, additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

1026.66 Rock Slide Mount Jarvis There is a recorded rock slide event along a similar section of the pipeline alignment. Rock 1.8x10-5 outcrops are located upslope of the alignment with mapped rockfall initiations zones, with – the pipeline located in the deposition zone. The recommended mitigation of increasing the 1027.12 pipeline wall thickness to extra heavy wall (19 mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a reduction in the pre-mitigated FLoC. Given the space limitations upslope of the RoW, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1026.71 Rock Mount Jarvis 2 In the region between the Coquihalla Summit and Hope, there is evidence of approximately 3.8x10-5 Avalanche five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1028.17 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1027.12 Rock Slide Mount Jarvis There is a recorded rock slide event along a similar section of the pipeline alignment. Steep, 1.1x10-5 gullied, bedrock outcrops are located upslope of the alignment, with the pipeline located in – the deposition zone. The recommended mitigation of increasing the pipeline wall thickness 1027.41 to extra heavy wall (19 mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a reduction in the pre-mitigated FLoC. Given the space limitations upslope of

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC the RoW, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1027.87 Rock Slide Mount Jarvis There is a recorded rock slide event along a similar section of the pipeline alignment. The 1.1x10-5 recommended mitigation of increasing the pipeline wall thickness to extra heavy wall (19 – mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a reduction 1028.17 in the pre-mitigated FLoC. Given the space limitations upslope of the RoW, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1028.17 Rock Mount Jarvis 3 In the region between the Coquihalla Summit and Hope, there is evidence of approximately 1.6x10-5 Avalanche five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1030.66 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1028.69 Rock Slide Mount Jarvis There is a recorded rock slide event along a similar section of the pipeline alignment. The 2.2x10-5 recommended mitigation of increasing the pipeline wall thickness to extra heavy wall (19 – mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a reduction 1029.25 in the pre-mitigated FLoC. Given the space limitations upslope of the RoW, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1029.25 Rock Slide Mount Jarvis There is a recorded rock slide event along a similar section of the pipeline alignment. The 1.7x10-5 recommended mitigation of increasing the pipeline wall thickness to extra heavy wall (19 – mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a reduction 1029.69 in the pre-mitigated FLoC. Given the space limitations upslope of the RoW, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1029.79 Scour Coquihalla River An additional 0.5 m of increased depth of cover will be added to the depth of cover required 1.2x10-5 to prevent exposure up to the 200-year flood event (to attain a total depth of cover of 3 m), – and the crossing has been designed with extra heavy wall (19 mm) and the use of concrete 1029.92 coating on the pipe. Subsurface investigation and local experience indicate that this site is not feasible geotechnically for HDD. Given local site conditions, additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

1030.66 Rock Mount Jarvis 4 In the region between the Coquihalla Summit and Hope, there is evidence of approximately 1.2x10-5 Avalanche five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1032.5 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1040.13 Scour Coquihalla River An additional 0.5 m of increased depth of cover will be added to the depth of cover required 2.6x10-5 to prevent exposure up to the 200-year flood event (to attain a total depth of cover of 2 m), – and the crossing has been designed with extra heavy wall (19 mm) and the use of concrete 1040.47 coating on the pipe. Subsurface investigation and local experience indicate that this site is not feasible geotechnically for HDD. Given local site conditions, additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

1040.73 Rock Hope Mountain In the region between the Coquihalla Summit and Hope, there is evidence of approximately 1.7x10-5 Avalanche five to seven post-glacial rock avalanche deposits. These deposits are located along a 48 – km long section of the alignment subject to a rock avalanche hazard. It is unlikely that any 1043.11 practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1041.8 Debris Hope (Charles) Historic debris flow occurrences have been recorded. The upstream drainage basin is steep 3.9x10-5 Flow (Ryan) Creek and has multiple debris sources, while the fan contains multiple avulsion channels and – several levees. The mitigations including 3 m depth of cover and rip rap overtop of the 1041.85 pipeline, increasing the pipeline wall thickness to heavy wall (14.7 mm), and installing concrete coating on the pipeline results in a reduction in the in the pre-mitigated FLoC. Given the local site conditions, additional mitigations to further reduce the FLoC are not feasible and/or results in a marginal reduction in FLoC.

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC

1049.74 Rock South Slope – In the region between Hope to Bridal Falls, there is evidence of approximately five post- 2.5x10-5 Avalanche Ruby Creek glacial rock avalanche deposits. These deposits are located along a 40 km long section of – the alignment subject to a rock avalanche hazard. Historic evidence of rock avalanche 1051.45 deposits are visible along the toe of the slope and along the Fraser River floodplain. This section of the alignment has a published rock avalanche event within the last glaciation. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1051.54 Rock Hunter Creek In the region between Hope to Bridal Falls, there is evidence of approximately five post- 1.5x10-5 Avalanche Slopes glacial rock avalanche deposits. These deposits are located along a 40 km long section of – the alignment subject to a rock avalanche hazard. Historic evidence of rock avalanche 102.59 deposits are visible along the toe of the slope and along the Fraser River floodplain. This section of the alignment has a published rock avalanche event within the last glaciation. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1052.59 Rock Ruby Creek In the region between Hope to Bridal Falls, there is evidence of approximately five post- 2.3x10-5 Avalanche Slopes glacial rock avalanche deposits. These deposits are located along a 40 km long section of – the alignment subject to a rock avalanche hazard. Historic evidence of rock avalanche 1054.15 deposits are visible along the toe of the slope and along the Fraser River floodplain. This section of the alignment has a published rock avalanche event within the last glaciation. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1058.64 Lateral Wahleach/Jones Setback of overbend and sag bends have been designed to accommodate floods up to the 1.2x10-5 Erosion Creek 200-year event without exposure of the pipeline at a setback distance of 20 m from the right – (Bank bank and 50 m from the left bank, and the crossing has been designed with heavy wall 1058.79 Erosion) (14.7 mm) and the use of concrete coating on the pipe. Additional mitigation to further reduce the FLoC is not practical, and/or results in a marginal reduction in FLoC. This site will be included as part of the natural hazards (geohazards) and real-time flood monitoring program to monitor for progression of the hazard should it occur and initiate intervention prior to exposure.

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC

1059.15 Rock Unnamed Slope In the region between Hope to Bridal Falls, there is evidence of approximately five post- 4.6x10-5 Avalanche 1 - Laidlaw glacial rock avalanche deposits. These deposits are located along a 40 km long section of – the alignment subject to a rock avalanche hazard. Historic evidence of rock avalanche 1062.3 deposits are visible along the toe of the slope and along the Fraser River floodplain. This section of the alignment has a published rock avalanche event within the last glaciation. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1066.77 Rockfall Mount Ludwig Large boulders located downslope of the alignment are visible in LiDAR, Google Earth, and 2x10-5 South Slope have been confirmed in the field. A talus slope and an exposed bedrock outcrop is located – upslope of the proposed alignment. The talus slope is sparsely vegetated with deciduous 1067.65 trees and the talus is vegetated with moss. The larger boulders are located in a cleared ROW for a transmission powerline. Mature deciduous trees are located between the large boulders and talus slope. The recommended mitigation of increasing the pipeline wall thickness to heavy wall (14.7 mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a significant reduction in the pre-mitigated FLoC. Given the limited space adjacent to the RoW, and the inaccessible rockfall sources, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

1070.7 Rock Cheam Peak In the region between Hope to Bridal Falls, there is evidence of approximately five post- 2.6x10-5 Avalanche North glacial rock avalanche deposits. These deposits are located along a 40 km long section of – the alignment subject to a rock avalanche hazard. Historic evidence of rock avalanche 1072.49 deposits are visible along the toe of the slope and along the Fraser River floodplain. This section of the alignment has a published rock avalanche event within the last glaciation. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1070.7 Rock Cheam Peak In the region between Hope to Bridal Falls, there is evidence of approximately five post- 3.9x10-5 Avalanche South glacial rock avalanche deposits. These deposits are located along a 40 km long section of – the alignment subject to a rock avalanche hazard. Historic evidence of rock avalanche 1072.49 deposits are visible along the toe of the slope and along the Fraser River floodplain. This section of the alignment has a published rock avalanche event within the last glaciation. It is unlikely that any practical mitigation would reduce the rock avalanche geohazard below

Post- KP Geohazard Geohazard Risk reduction strategies utilized to reduce geohazard to ALARP Mitigated Range Type Name FLOC the FLoC threshold. The consequences from the rock avalanche geohazard may be reduced by valve spacing or other consequence reducing techniques.

1076.97 Rock Slide Mount Archibald Evidence of historic rockslide activity upslope and downslope of the alignment. The 2.5x10-4 proposed alignment passes through a talus field that has been interpreted as a rock slide – deposit. The recommended mitigation of increasing the pipeline wall thickness to heavy 1077.61 wall (14.7 mm) and increasing the depth of cover overtop of the pipeline to 2.3 m results in a reduction in the pre-mitigated FLoC. Given the space limitations upslope of the RoW, additional mitigation to further reduce the FLoC is not practical and/or results in a marginal reduction in FLoC.

APPENDIX A GEOHAZARD RANKING SHEETS

Table A – 1 Governing equation to estimate loss of containment from a geohazard.

FLoC(i) = Frequency of a loss of containment due to a geohazard at location i, expressed as an annual frequency, in events per year.

l(i) = Occurrence is a factor of 0 or 1 expressing whether a potential geohazard has credible opportunity to occur at location i.

MI(i) = Mitigation effects expressed as a factor of 0 on I(i). Represents the removal of the geohazard as a result of the lack of a credible opportunity due to a specific mitigation applied at location i.

F(i) = Frequency of occurrence of the geohazard at location i expressed as an annual frequency, in events per year.

MF(i) = Mitigation effects expressed as a reduction factor on F(i) between 0 and 1. Represents the reduction in the geohazard frequency due to a specific mitigation applied at location i.

GOVERNING EQUATION SH(i) = Spatial probability expressed as a conditional RELATING THE FREQUENCY OF probability that the geohazard would horizontally A LOSS OF CONTAINMENT (LoC) reach an imaginary vertical plane that extends from EVENT RELATED TO through the pipeline centerline to the ground surface GEOHAZARD IS DEFINED AS: at location i, given the occurrence of the geohazard. Where; MSH(i) = Mitigation effects expressed as a reduction factor on SH(i) between 0 and 1. Represents the reduction in FLoC(i) = I(i) x F(i) x SH(i) x SV(i) x V(i) x the spatial horizontal probability of a geohazard M (I,F,SH, SV,V(i)) reaching the centerline in plan due to a specific mitigation applied at location i.

SV(i) = Spatial probability expressed as a conditional probability that a geohazard would vertically reach the pipeline through the depth of cover at location i, given the occurrence of the geohazard and the geohazard reaching the pipeline centerline at the ground surface.

MSV(i) = Mitigation effects expressed as a reduction factor on SV(i) between 0 and 1. Represents the reduction in the spatial vertical probability due to a specific mitigation applied at location i.

V(i) = Vulnerability of the pipeline to loss of containment expressed as a conditional probability, between 0 and 1, given that a geohazard has reached and touched or exposed the pipeline at location i.

MV(i) = Mitigation effects expressed as a reduction factor on V(i) between 0 and 1. It represents the reduction in the pipeline’s vulnerability to loss of containment due to a specific mitigation applied at location i.

Table A – 1 ROCK SLOPE GEOHAZARD: ROCKFALL

General Process Description Fragments of rock detach from a steep rock outcrop and travel downslope independently with a free falling, bouncing, or rolling motion (<1,000 m3 total volume of fragmental rockfall boulders; larger events are classified as rock slide). Required Conditions for Geohazard 1. Natural or constructed steep rock slopes (>35°) with discontinuities that form discrete rock blocks that may release from the slope. Geohazard Assessment Data Sources 1. Surficial geology terrain mapping. 2. Historical aerial photograph review. 3. LIDAR topography. 4. Slope angle maps generated from a LIDAR survey. 5. Google EarthTM imagery. 6. Site observations, published information on regional occurrences, corporate history, and/or industry experience. Triggering Mechanisms Rockfall events are typically triggered by intense or prolonged rainfall, freeze-thaw action, snowmelt or channelized surface water runoff, erosion, root jacking, and seismic events. Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. Recorded rockfall events, or rockfall occurrence observed along or near the proposed pipeline right-of-way (RoW). 2. Rock outcrops with slope angles greater than 35° within 100 m slope distance upslope of the RoW (without a natural barrier 1.0 = Credible (meets some or between the outcrop and RoW). all of the screening criteria). I(i) 3. Rockfall initiation zones (R”b) consisting of bedrock outcrops within 500 m slope distance upslope of the RoW (without a 0 = Not credible (does not meet natural barrier between the outcrop and RoW). any of the screening criteria). 4. Field evidence of a credible rockfall hazard based on field observations of rockfall deposits/talus in the near vicinity of the pipeline alignment. Field confirmation of one or more of the screening criteria. Description of Frequency The rockfall frequency is estimated based on visual indicators of the Use F = 1 if there is evidence of presence of rockfall activity, development of a rockfall talus slope, and recent rockfall activity, or the rockfall runout zone vegetation cover (i.e. non-vegetated, moss talus slope and rockfall runout coverage, tree coverage and tree age). zone is not vegetated. Field observations are used to revise or validate the rockfall frequency Use F = 0.1 if a rockfall talus by summing the number of rockfall events divided by a credible slope has developed, there is observation period. The credible observation period is based on field evidence of activity within the F(i) observations of vegetation cover in the deposition zone (i.e. non- past 10 years, and the talus vegetated, moss coverage, tree coverage and tree age) and the slope or rockfall runout zone is geomorphic history of the area (i.e. time since glaciation or estimated vegetated with pioneering age of the rock cut). A frequency greater than 1 may be considered in vegetation. special cases where potentially damaging rocks are expected to fall Use F = 0.01 if a rockfall talus more frequently than 1 per year. slope or runout zone is Site observations, Google EarthTM imagery, LiDAR topography and vegetated with second growth aerial photographs were used to assess the rockfall initiation zones, deciduous trees and young talus slopes and rockfall runout attributes. conifers.

Use F = 0.001 if a rockfall talus slope is vegetated with old growth trees.

Potential for Hazard to Horizontally Reach the Centerline This factor is the spatial probability that a rockfall, given its occurrence, Use SH = 0.1 for locations with lands or crosses on the pipeline centerline. potential for direct rockfall impact, and for pipelines The rockfall runout spatial probability is estimated based on the location located within 45° (from the of the pipeline centerline relative to the rockfall runout shadow angle horizontal) of the base of the measured from the horizontal (Evans & Hungr 1993; Holm & Jakob SH(i) rock slope or apex of the talus 2009; Pierson et al. 2001). slope. Where field observations exist, the spatial probability may be revised or Use SH = 0.05 for 35° to 45°. validated by summing the number of observed rockfall events at or beyond the pipeline alignment and dividing by the total number of Use SH = 0.01 for 27° to 35°. rockfall events, then estimating the proportion of rocks reaching the Use SH = 0.001 for 22° to 27°.

alignment that could directly impact the pipe centerline. Use SH = 0.0001 for <22°. Potential for Hazard to Vertically Reach the Pipeline This factor is the spatial probability that a rockfall penetrates through the depth of cover and impacts the pipe given its occurrence and lands on the pipeline centerline. The rockfall spatial parameters is based on penetration depths predicted by Pichler et al. (2005) for an assumed depth of cover of 0.8 m above the pipeline. A lower rockfall energy and penetration is expected when deposition occurs along talus slopes, rather than as direct impact following free fall. The spatial values for indirect rockfall have been adjusted by one bin to account for the decrease in rockfall energy and penetration for indirect impacts and along talus slopes. Table A-1a – Spatial Values Based on Fall Height and Block Length for Direct Impacts. >30 0.5 1 1 1 1 Table A-1a and Table A-1b summarize the spatial values Fall 20-30 0.1 0.5 1 1 1 Height for the rockfall to penetrate (m) 10-20 0.01 0.1 0.5 1 1 through the depth of cover SV(i) <10 0.001 0.01 0.1 0.5 1 based on the rockfall height and the average block size for Boulder Side <1 1-2 2-3 3-4 >4 direct rockfall impacts and Length (m) indirect impacts on talus 3 Volume (m ) <1 1-8 8-27 27-64 >64 slopes. Block Size

Table A-1b – Spatial Values Based on Fall Height and Block Length for Indirect Impacts and Talus Slopes. >30 0.1 0.5 0.5 0.5 0.5 Fall 20-30 0.01 0.1 0.5 0.5 0.5 Height (m) 10-20 0.001 0.01 0.1 0.5 0.5 <10 0.0001 0.001 0.01 0.1 0.5 Boulder Side <1 1-2 2-3 3-4 >4 Length (m) Volume (m3) <1 1-8 8-27 27-64 >64 Block Size

Description of Effects in Hazard Impact Area The vulnerability of the pipeline to rockfall impact depends on: 1. The impact energy of the boulder transmitted to the pipeline through the soil cover from the falling, bouncing or rolling boulders. 2. The penetration depth of the boulder point of impact as it intercepts the pipeline when falling, bouncing, or rolling. Rockfall energy and penetration depths increase with higher fall heights and larger boulder sizes. Rockfall energy has been assumed as a proxy for pipeline vulnerability in this assessment based on the maximum allowable impact energy. Vulnerability values based on the rockfall fall height and the V(i) Table A-1c – Vulnerability Values Based on Fall Height and Block Length for block size are summarized in Rockfall Impacts Table A-1c. >30 1 1 1 1 1 Fall Height 20-30 0.5 1 1 1 1 (m) 10-20 0.1 1 1 1 1

<10 0.01 0.1 1 1 1 Boulder Side <1 1-2 2-3 3-4 >4 Length (m) Volume (m3) <1 1-8 8-27 27-64 >64 Block Size

Examples of Potential Mitigation Options Options to Reduce Frequency Use MF = 0.1 to 0.9 for installation of rock support. 1. Install rock bolts, rock anchors and other mechanical rock slope support. Re-calculate the FLOC based on revised pipeline location. Options to Reduce the Hazard Horizontally Reaching the Centerline Use MSH = 0.1 to 0.5 for 1. Relocated the pipeline to avoid areas subject to rockfall. rockfall catchment structures.

2. Install a rockfall catchment structure such as nets, trenches, Use MSH = 0.01 to 0.1 for ditches of berms. rockfall barriers.

3. Install a rockfall barrier such as a tunnel or a shed. Use MSV = 0.05 to 0.5 for Options to Reduce the Hazard Vertically Reaching the Pipeline increased depth of cover M(i) 1. Increase depth of soil cover over top of the pipeline. above the pipe. 2. Install physical protection above the pipeline such as concrete Use MSV = 0.1 to 0.9 for covers rubber mats, or steel plates. physical protection above the pipeline. 3. Improve the trench backfill by installing energy absorbing backfill to reduce impact forces. Use MSV = 0.5 to 1 for energy absorbing backfill. Options to Reduce Vulnerability Use MV = 0.8 for 14.7 mm pipe 1. Install heavy wall pipe. and MV = 0.6 for 19 mm pipe. 2. Install concrete coated pipe. Use MV = 0.5 to 0.9 for At locations where multiple types of mitigation are proposed, a lower installing concrete coated pipe. limit was set at 0.01 for the cumulative mitigation value.

Table A – 2 ROCK SLOPE GEOHAZARD: EXTREMELY RAPID ROCKSLIDE

General Process Description A large rock mass releases from a steep rock outcrop along one or more discontinuities (rock mass faults, joints, or shears) and travels downslope extremely rapidly (>3 m/s velocity; size ~1,000 m3 to 100,000 m3 total volume of rock mass). The rockslide mass fails as a coherent mass (translational, stepped-translational, toppling, or wedge release) before breaking up with increased travel distance from the source area. Required Conditions for Geohazard 1. Natural or constructed steep rock slopes (>35°) with discontinuities capable of releasing rock masses of ~1,000 m3 to 100,000 m3 volume; or, shallower slopes (as low as 15°) with unfavorably oriented low- strength rock structure (persistent bedding or foliation). Geohazard Assessment Data Sources 1. Surficial geology terrain mapping. 2. Historical air photograph review. 3. Slope angle maps generated from LIDAR survey. 4. Google EarthTM imagery. 5. Site observations, published information on regional occurrences, corporate history, and/or industry experience. Triggering Mechanisms Rockslide events are typically triggered by intense or prolonged rainfall, freeze-thaw action, snowmelt or channelized surface water runoff, erosion, root jacking, and seismic events. Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. Recorded rockslide events, or rockslide occurrence observed within the pipeline corridor. 2. Rock outcrops (>10 m vertical height) with slope angles greater than 35° within 100 m slope distance upslope of the 1.0 = Credible (meets some pipeline (without a natural barrier between the outcrop and or all the screening criteria). pipeline). I(i) 3. Rockfall initiation zones (R”b) consisting of bedrock outcrops 0 = Not credible (does not within 500 m slope distance upslope of the corridor (without meet any of the screening a natural barrier between the outcrop and corridor). criteria). 4. Field evidence of a credible rockslide hazard based on field observations of rock outcrops and presence of rockslide deposits near the pipeline alignment. Field confirmation of one or more of the screening criteria.

Description of Frequency A regional frequency approach is used to estimate the frequency of rock slide along the alignment. The frequency is estimated based on visual evidence of rock slide activity as inferred from LIDAR topography, Google EarthTM imagery, aerial photographs and field reconnaissance, including ground reconnaissance of deposit areas and helicopter reconnaissance of potential release zones. The number of rock slide deposits or indications of ridge elevation F = Varies depending on instabilities is divided by a credible observation period (assumed as rock slide frequency and F(i) 5,000 years for rock slides based on work by Hungr & Evans (1993)) length of alignment exposed to yield a rock slide frequency. Using this approach, it is assumed to the rock slide hazard. that only half of the rock slide events that occurred over the credible observation period have been detected. As such, the estimated number of rock slide events has been doubled to account for undetected occurrences. A rock slide frequency per km is estimated by dividing the rock slide frequency by the total length of credible hazard along the alignment. The frequency for each rock slide segment is estimated by multiplying the frequency per km by the individual rock slide segment length. Initiation Zone Potential for Hazard to Horizontally Reach the Centerline Use SH = 1 for pipelines located in the initiation zone. This factor is the conditional probability that displaced material from a potential rockslide will reach the pipeline centerline given that the Transport Zone rockslide event occurs. Use SH = 1 for pipelines It has been assumed that the rockslide material will reach the pipeline located in the transport if the pipeline is located in the rockslide initiation or transport zones. zone. Deposition Zone SH(i) In the deposition zone, the rockfall runout spatial probability is estimated based on the location of the pipeline centerline relative to Use SH = 1 if the pipeline is the rockslide runout shadow angle measured from the horizontal located within 35° (from the (Evans & Hungr 1993; Holm & Jakob 2009). horizontal) of the base of the Field observations may be used to validate or revise the spatial rock slope/apex of the talus probability of impact by summing the number of observed rockslide slope. events that reached or passed the pipeline alignment, and dividing by Use SH = 0.1 for 27° to 35°.

the total number of rockslide events in the rockslide area. Use SH = 0.01 for 22° to 27°.

Use SH = 0.001 for <22°. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that displaced material from a Initiation Zone potential rockslide will make it through the depth of cover and impact Use SV = 1.0. the pipeline given that the rockslide event occurs and reaches the pipeline. Transport Zone SV(i) It is assumed that the pipeline will be impacted by rockslide if the Use SV = 1.0. pipeline is in the initiation and transport zone. In the deposition zone, Deposition Zone the spatial probability is decreased based on the assumption that the Use SV = 0.1. energy of the rock slide material decreases with distance from the initiation zone. Description of Effects in Hazard Impact Area The vulnerability of the pipeline to rockslide impact depends on: 1. The impact force and penetration depth of the rockslide mass transmitted to the pipeline through the soil cover V(i) (standard construction method). Use V = 1. 2. The size of the rockslide. It is assumed that a loss of containment would occur if the pipeline is impacted by a rockslide. This assumption is based on professional judgment.

Use M = 0.1 to 0.8 for RoW grading or installation of Examples of Potential Mitigation Options ground and surface water Options to Reduce Frequency controls. 1. For smaller slides, grade the RoW to reduce the driving Re-calculate the FLOC forces or install groundwater or surface water controls. based on revised pipeline location. Options to Reduce the Hazard Horizontally Reaching the Centerline Use MSH = 0.2 to 0.8 for 1. Relocate the pipeline to avoid areas subject to geohazards rock slide catchment or increase the distance between the pipeline and the structures. geohazard. Use MSH = 0.05 to 0.1 for 2. Install a rockslide catchment structures such as trenches, rock slide barriers. berms, ditches, or walls. Use MSV = 0.5 to 0.9 for 3. Install a barrier such as a tunnel or a shed. increased the depth of soil Options to Reduce the Hazard Vertically Reaching the Pipeline cover above the pipe if the M(i) 1. Increase depth of soil cover above the pipe if the pipeline is pipe is in the deposition in the deposition zone. zone. 2. Increase the depth of cover with trenchless methods. Use MSV = 0.001 to 0.1 for increasing the depth of 3. Install physical protection above the pipeline such as cover with trenchless concrete covers, rubber mats, or steel plates. methods. Options to Reduce Vulnerability Use MSV = 0.5 to 0.9 for 1. Install heavy wall pipe. physical protection above 2. Install concrete coated pipe if the pipeline is in the deposition the pipeline. zone. Use MV = 0.9 for 14.7 mm pipe and MV = 0.7 for At locations where multiple types of mitigation are proposed, a lower 19 mm pipe. limit was set at 0.1 for the cumulative mitigation value. Use MV = 0.5 to 0.9 for installing concrete coated pipe.

Table A – 3 ROCK SLOPE GEOHAZARD: EXTREMELY RAPID ROCK AVALANCHE

General Process Description A large rock mass releases from a steep rock outcrop along one or more discontinuities (rock mass faults, joints, or shears). The released material travels downslope extremely rapidly with high mobility (flow-like movement) and runout distances that can exceed several kilometers (size 0.1M m3 to >100M m3 total volume of rock mass). Required Conditions for Geohazard 1. Natural steep rock slopes (>35°) with discontinuities capable of releasing large rock masses (>100,000 m3). Geohazard Assessment Data Sources 1. Surficial geology and terrain stability mapping. 2. Historical aerial photographs review and interpretation. 3. LIDAR topography. 4. Slope angle maps generated from a LIDAR survey. 5. Google EarthTM imagery. 6. Site observations, published information on regional occurrences, corporate history, and/or industry experience. Triggering Mechanisms Rock avalanche events may be triggered by intense or prolonged rainfall, successive above average rainfall seasons, seismic events; or, they may lack a defined triggering mechanism and be caused by progressive failure developing over time along controlling structures and/or within the rock mass. Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. Recorded rock avalanche events, or rock avalanche 1.0 = Credible (meets some occurrence observed adjacent to the corridor. or all the screening criteria).

I(i) 2. Field evidence of a credible rock avalanche hazard based on field observations of unfavorable rock structure (i.e. 0 = Not credible (does not tension cracks, lineaments) along mountain ridge tops meet the screening criteria). and/or presence of rock avalanche deposits near the pipeline alignment.

Description of Frequency A regional frequency approach is used to estimate the frequency of rock avalanche. Five geographical rock avalanche “regions” have been defined based on unique geological and geomorphological characteristics. The frequency of rock avalanche for each region is estimated based on visual evidence of rock avalanche activity as TM inferred from LIDAR topography, Google Earth imagery, aerial F = Varies depending on photographs and field reconnaissance, including ground regional rock avalanche reconnaissance of deposit areas and helicopter reconnaissance of frequency and length of F(i) potential release zones. Within each geographic region, the number alignment exposed to the of rock avalanche deposits or indications of ridge-elevation rock avalanche hazard. instabilities is divided by a credible observation period (generally taken as 10,000 years for rock avalanche) to yield a regional rock avalanche frequency. The regional rock avalanche frequency is divided by the total length of credible hazard within the region, to yield a regional frequency per km. The frequency for each rock avalanche segment is estimated by multiplying the regional frequency per km by the individual rock avalanche segment length.

Initiation Zone

Use SH = 1 for pipelines located in the initiation zone. Potential for Hazard to Horizontally Reach the Centerline Transport Zone This factor is the conditional probability that displaced material from a Use SH = 1 for pipelines potential rock avalanche will reach the pipeline centerline and given locate in the transport zone. that the rock avalanche event occurs. Deposition Zone

It has been assumed that the rock avalanche debris will reach the Use SH = 1 if the pipeline- pipeline centerline in the transport zone (from the initiation zone to the initiation zone H/L ratio is SH (i) base of the slope or shallower slopes of the deposition zone). >0.7.

In the deposition zone, the rock avalanche debris runout spatial Use SH = 0.5 for H/L ratio of parameter has been estimated based on the relative elevation (height 0.4 to 0.7.

- H) and relative horizontal distance (runout length - L) ratio of the rock Use SH = 0.1 for H/L ratio of 3 avalanche initiation zone and the pipeline assuming a 1,000,000 m 0.3 to 0.4. failure mass (McDougall et al. 2012). Use SH = 0.01 for H/L ratio of 0.2 to 0.3.

Use SH = 0.001 for H/L ratio of <0.2. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that displaced material from a potential rock avalanche will impact the pipeline through the depth of cover given that the rock avalanche event occurs and reaches the Initiation Zone pipeline. Use SV = 1.0. The spatial impact parameter depends on: Transport Zone

1. The horizontal distance of the pipeline from the rock Use SV = 1.0. avalanche initiation zone. The impact force of the rock Deposition Zone avalanche debris and ground deformation transmitted to the SV(i) pipeline through the soil cover (standard construction For pipeline trenches in rock method) decreases with increasing horizontal distance from or dense/hard soils, use the initiation zone. SV = 0.1. 2. The type of material the pipeline trench is traversing rock, For soft soils use, SV = 1.0 dense tills, gravels, silts, clays, or peats. for H/L ratio of >0.7; and use It is assumed that the pipeline will be impacted by the rock avalanche SV = 0.5 for a H/L ratio of material if the pipeline is in the initiation or transport zone. In the <0.7. deposition zone, the spatial probability is decreased based on the density of the material surrounding the pipeline and the distance from the initiation zone.

Description of Effects in Hazard Impact Area The vulnerability of the pipeline to a rock avalanche depends on the penetration depth of the rock avalanche debris and the impact force V(i) transmitted to the pipeline. Use V = 1. It is assumed that a loss of containment will occur if the pipeline is impacted by a rock avalanche as defined with a minimum 1,000,000 m3 failure mass.

Examples of Potential Mitigation Options Options to Reduce Frequency Re-calculate the FLOC M(i) 1. Not applicable. based on revised pipeline Options to Reduce the Hazard Horizontally Reaching the Centerline location.

1. Relocate the pipeline to avoid areas subject to the Use MSH = 0.5 to 0.9 for geohazard or increase the distance between the pipeline rock avalanche catchment and the geohazard. structures.

2. Install a rock avalanche catchment structures such as Use MSH = 0.5 to 0.9 for trenches, berms, ditches, or walls. rock avalanche barriers.

3. Install barriers such as a tunnel or a shed. Use MSV = 0.5 to 0.9 for Options to Reduce the Hazard Vertically Reaching the Pipeline increased depth of soil cover above the pipe if the 1. Increase the depth of cover. pipe is in the deposition 2. Increase the depth of cover with trenchless methods. zone.

3. Install physical protection above or around the pipeline such Use MSV = 0.001 to 0.1 for as a concrete cover. increasing the depth of Options to Reduce Vulnerability cover with trenchless methods. 1. Install heavy wall pipe. Use MSV = 0.9 to 1 for

physical protection above At locations where multiple types of mitigation are proposed, a lower the pipeline. limit was set at 0.1 for the cumulative mitigation value. Use MV = 0.95 for 19 mm pipe.

Table A – 4 SOIL SLOPE GEOHAZARD: DEBRIS SLIDE/AVALANCHE

General Process Description A shallow layer of weak soil or weathered rock overlying more competent soil or bedrock that detaches and slides rapidly down a steep slope. Debris slides/avalanches may entrain additional material as they slide down slope, and can evolve into debris flows if they enter a channel with sufficient water. Rates of entrainment and deposition depend on slope morphology (open slope versus channel) and slope angle, as well as grain size and moisture in the moving mass. Required Conditions for Geohazard 1. Steep natural slopes (>30°), usually with a thin veneer of soil or weathered rock over bedrock. Geohazard Assessment Data Sources 1. Surficial geology and terrain stability mapping. 2. Historical air photograph review and interpretation. 3. LIDAR topography. 4. Slope angle map based on a LIDAR survey. 5. Google EarthTM imagery. 6. Published information on regional occurrences, corporate history, and/or industry experience. 7. Site observations of soil conditions, slope geometry, evidence of historical activity, and surface and groundwater conditions. Triggering Mechanisms Debris slides/avalanches are typically triggered by intense or prolonged rainfall, freeze-thaw action, snowmelt or channelized surface water runoff, erosion, and significant seismic events.

Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. Recorded debris slide/avalanche activity as observed in available imagery. 2. Hazard has been specifically identified in the terrain stability mapping. 1.0 = Credible (meets some or all the screening criteria). 3. Hazard has not been specifically identified, but terrain I(i) stability class has been mapped as IV or V and slope angle exceeds 30°. 0 = Not credible (does not 4. Evidence of a credible debris slide hazard based on field meet the screening criteria). observations (i.e. tension cracks, debris slide scars) and presence of debris slide deposits near the pipeline alignment. Field confirmation of one or more of the screening criteria.

Use F = 1 if fresh (i.e. ~ 1 to 5 years old) scars are evident within the landform in recent imagery or from Description of Frequency field observations. The debris slide frequency relies on review of existing mapped Use F = 0.1 if fresh scars are occurrences and their approximate return period. Frequencies of evident in older imagery occurrence in the region have been assigned to similar geological within the landform and do units based on terrain stability class and primary surficial material not appear fresh in recent type. The temporal and spatial frequency of debris slides has been imagery. inferred by examining similar landforms in LIDAR and aerial photographs. Use F = 0.01 if fully F(i) revegetated scars are Field observations are used to validate or revise the frequency of evident within the landform occurrence of debris slides/avalanches over a credible observation in older or recent imagery, or period. The credible observation period is based on the field if fresh scars are present in observations of the vegetation cover of the debris slide deposits (i.e. similar nearby landforms. non-vegetated, tree coverage, and tree age). Use F = 0.001 if no scars are Site observations, Google EarthTM imagery, LiDAR topography, and evident within the landform aerial photographs were used to assess the debris slide initiation but it meets some or all the zones, talus slopes and rockslide runout attributes. occurrence screening criteria, or if old scars are present in similar nearby landforms.

Use SH = 1 if fresh or visible older landslide scars cross the pipeline alignment.

Use SH = 0.1 if scars do not reach the pipeline Potential for Hazard to Horizontally Reach the Centerline alignment, but pipe is in a The spatial probability that the debris slide reaches the pipeline potential initiation or centerline is based on field evidence of run-out/travel distance, as well transport zone, or average as consideration of documented runout of similar events described in slope angle from potential the literature. initiation zones to the The potential for the debris movement to reach the pipeline in the alignment exceeds 27°. deposition zone is based on a review of typical maximum travel Use SH = 0.01 if scars do not SH(i) distances for a range of soil types within several landslide databases reach the pipeline (McDougall et al. 2012; Corominas 1996). These maximum travel alignment, but average distances are correlated to landslide volumes. slope angle from potential Where field observations exist, the spatial probability of impact is initiation zones to the validated or revised by summing the number of observed debris slide alignment is between 22° events that reach or go beyond the pipeline alignment and dividing by and 27°. the total number of debris slide events. Use SH = 0.001 if the hazard has been determined to be credible, but average slope angle from potential initiation zones to the alignment is less than 22°. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that the debris slide would impact the pipeline given the debris slide event occurs and reaches the pipeline centerline. SV(i) Use SV = 1. It is assumed that the debris slide would impart stresses on the pipeline through the depth of cover under typical burial conditions if the debris slide material reaches the pipeline centerline or if the debris slide scarps cross the pipeline.

Description of Effects in Hazard Impact Area The vulnerability of the pipeline to debris slides is based on case histories and professional judgement. The slide length along the pipeline has been used to differentiate the vulnerability to debris slides in this assessment. Vulnerability values are summarized in Table A-4 if the pipeline is in the initiation Table A-4 – Vulnerability Values Based on the Slide Length Along the Pipeline V(i) for Debris Slides. or transport zone. Use V = 0.001 if the pipeline Vulnerability Slide Length (m) is in the debris slide runout Values zone. <150 0.01 150 - 300 0.1 >300 0.5

Set I = 0 if grading the RoW grading removes the Examples of Potential Mitigation Options hazard.

Options to Reduce Frequency Use MF = 0.05 to 0.8 for 1. Grade the right-of-way to reduce the overall slope angle and grading the RoW, or remove the debris slide hazard. installing groundwater and surface water control, or 2. Dewatering/drainage, erosion protection, or groundwater install a toe berm. and surface water management, although for very large areas these measures may not be practical. Re-calculate the FLOC based on revised pipeline Options to Reduce the Hazard Horizontally Reaching the Centerline location. 1. Increase the distance between the pipeline and the Use MSH = 0.1 to 0.5 for geohazard. debris slide barriers or 2. Install barriers such as trenches, berms, ditches, or walls in catchment structures. between the initiation zone and the pipeline. Use MSV = 0.1 to 0.8 for Options to Reduce the Hazard Vertically Reaching the Pipeline increasing the soil depth of 1. If the pipeline is in the deposition zone, increase the depth cover if the pipe is in the of cover to 1.5 meters to reduce loading on the pipe. deposition zone. 2. Install protective plates, mats, or concrete slabs if the Use MSV = 0.1 to 0.8 for pipeline is in the deposition zone. physical protection above M(i) Options to Reduce Vulnerability the pipeline. 1. Install heavy wall pipe. Use MV = 0.8 for 14.7 mm pipe and MV = 0.6 for 2. Install low friction coating to reduce loading on the pipeline 19 mm pipe. due to ground movements if the pipeline is in the initiation or transport zone and ground movements are parallel or Use MV = 0.2 to 0.9 for oblique to the pipeline. installing low friction coating. 3. Install concrete coated pipe to increase the resistance to Use MV = 0.1 to 0.9 for loading if the pipeline is in the deposition zone. installing concrete coated 4. Re-orient the pipeline down the slope or remove the micro- pipe if the pipeline is in the bends on the slope if the pipeline is in the initiation or deposition zone. transport zone. Use MV = 0.1 to 0.8 for re- 5. Install soft/loose/low density backfill to reduce the loading on orientating the pipe parallel the pipeline due to ground movement if the pipeline is in the to the slope movements or initiation or transport zone. removing micro-bends on the slope.

At locations where multiple types of mitigation are proposed, a lower Use MV = 0.5 to 0.9 if the limit was set at 0.01 for the cumulative mitigation value. trench is backfilled with soft/loose/low density backfill.

Table A – 5 SOIL SLOPE GEOHAZARD: EARTH LANDSLIDES

General Process Description A slow-moving mass of soil or very weak, highly weathered rock that moves primarily by sliding on a basal shear surface, potentially accompanied by internal deformation. This geohazard class includes all deep-seated, slowly moving landslides in soil, including: slow earthflows, translational slides, rotational slides (slumps) and spreads. Deep-seated slow movement in very weak rock is also considered in this geohazard class. Rapid earthflows and spreads are also included, but are expected to be very rare, or possibly absent, along the project. These various mechanisms may have distinctly different morphological characteristics but are often indistinguishable from geomorphic evidence, in the absence of subsurface information. The failure surface will typically be greater than 3 m deep (often much deeper), and movement rates will typically range up to several meters per year. This assessment considers large-scale ground movements that occur too quickly to be detected through typical pipeline operations. It has been assumed in this assessment that typical pipeline operations consist of an ongoing natural hazards management program and regular site inspections that will identify and actively manage geohazards. In addition, typical construction and grading practices were assumed such that deviations from ‘typical’ would not invalidate this assessment. While deep seated landslides in soil typically move very slowly, they can, rarely, accelerate and move suddenly several meters or tens of meters. Rapid earthflows or spreads will move tens or hundreds of meters at velocities exceeding 1 m/s. Required Conditions for Geohazard 1. Slopes with cohesive soil such as clay, silt, peat, or very weak and/or highly weathered rock. 2. Unfavorable groundwater conditions (high groundwater elevation or strong gradients and seepage pressures). 3. Presence of sensitive silt/clay is necessary for rapid earthflows and rapid spreads. Geohazard Assessment Data Sources 1. Surficial geology and terrain stability mapping. 2. Historical air photograph review and interpretation. 3. Slope angle map based on a LIDAR survey. 4. Google EarthTM imagery. 5. Published information on regional occurrences, corporate history, and industry experience. 6. Site observations of soil conditions, slope geometry, evidence of historical activity, and surface and groundwater conditions. Triggering Mechanisms Slow earth landslides typically move very slowly, often on an ongoing basis, with regular annual variation in rate of movement associated with cyclical changes in groundwater conditions. Acceleration of movement may be triggered by changes in groundwater pressures along the failure surface, and these may be closely connected with surface hydrologic input, thus acceleration may occur following sustained heavy rainfall or significant snowmelt. Acceleration of movement of slow earth landslides can also be triggered by external loading due to changes in slope geometry, or erosion along a slope toe. Rapid earthflows and spreads are usually triggered by erosion of natural riverbanks but can also be triggered by large earthquakes.

Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. The terrain has been identified as an active earth landslide in the terrain stability mapping. 1.0 = Credible (meets some or 2. Has been identified as an active, dormant, abandoned or relict earth landslide feature through subsequent all the screening criteria). I(i) geomorphic review of the available LiDAR and imagery. 3. Earth landslides have been identified on a corresponding 0 = Not credible (does not meet terrace or similar landform within the same valley. the screening criteria). 4. Field evidence of evidence of a credible landslide hazard based on field observations (i.e. tension cracks, landslide scarps) and presence of landslide deposits near the pipeline

alignment. Field confirmation of one or more of the other screening criteria.

Use F = 1 if an earth landslide is believed to be active, as evidenced by any indication of large scale instability around the body of the landslide. Use F = 0.1 for an evidently dormant earth landslide, or for Description of Frequency an evidently abandoned or relict earth landslide if other earth Frequency of earth landslide movement at existing earth landslide landslides in the same valley features depends on the state of the landslide activity. The analysis involving the same geology are of landslide frequency is based on a review of existing mapped active. Anthropogenic induced occurrences and their approximate return period. Frequencies of movement should be occurrence in the region have been assigned to similar geological considered at this frequency. F(i) units based on the terrain mapping. Use F = 0.01 for an evidently Field observations may be used to revise or validate the landslide abandoned or relict earth frequency by summing the number of landslides over a credible landslide if other earth observation period. The credible observation period is based on the landslides in the same valley field observations of the vegetation cover of the landslide deposits involving the same geology are (i.e. non-vegetated, tree coverage, and tree age) and geomorphic dormant, abandoned or relict, or history of the landslide prone area (i.e. time since last glaciation). if no other earth landslides are present. Use F = 0.001 where no earth landslide currently exists but the initiation of a new earth landslide is credible based on the observed presence of earth landslides on a related terrace in the same valley.

For existing slow earth landslides:

Use SH = 1 if the pipeline alignment crosses the body of the landslide.

Use SH = 0.1 if the pipeline alignment is within 30 m of the headscarp or toe.

Use SH = 0.01 if the pipeline alignment is within 100 m of the headscarp or toe.

Use SH = 0.001 if the pipeline is more than 100 m from the headscarp or toe. Potential for Hazard to Horizontally Reach the Centerline Where no earth landslide The spatial probability of the landslide reaching the pipeline centerline presently exists but the depends on the potential for spatial overlap between the pipeline and hazard of a new slow earth the body of the earth landslide. This probability can be different for landslide is credible: slow earth landslides versus rapid earthflows or spreads. There will be a lower probability of overlap for smaller events. Use the SH values above in relation to the headscarp or For slow earth landslides where field observations exist, the spatial toe elevations of the nearest probability of impact may be revised or validated by summing the 2 or 3 existing earth number of observed existing landslides events that extend from the landslides. toe of the slope or retrogress from the slope crest to the pipeline alignment divided by the total number of landslides in the area. If the landslide is expected SH(i) to be small (based on Rapid earth flows and spreads most commonly retrogress rearward regional evidence), the from the crest of the natural slope (i.e. river bank) and may involve value may be decreased by very flat terrain (i.e. with travel angles on the order of 1 to 2 degrees an order of magnitude. are possible). The length of retrogression may be correlated with height (or depth of incision) of the nearby river bank. Data tabulated Where the hazard of a new by Mitchell and Markell (1974) show the length of retrogression, R, for rapid earthflow or spread is rapid earthflows in sensitive clay typically ranging from R/H ~ 10 credible: (where H is the height of the river bank) to very rare cases where R/H Use SH = 1 if the pipeline ~ 100. This may also apply to regions with terraces or locations with alignment crosses within a nearby valley without a river. 10H from the adjacent river with bank height H. Use SH = 0.5 if the pipeline alignment crosses within 20H from the adjacent river.

Use SH = 0.1 if the pipeline alignment crosses within 60H from the adjacent river.

Use SH = 0.01 if the pipeline alignment crosses within 100H from the adjacent river.

Use SH = 0.001 if the pipeline alignment is more than 100H from the adjacent river.

Potential for Hazard to Vertically Reach the Pipeline

This factor is the conditional probability that landslide would impact the pipeline given that the landslide event occurs and reaches the SV(i) pipeline centerline. Use SV = 1.

It is assumed that the landslide would impact the pipeline, if a landslide event occurs and reaches the pipeline centerline under typical burial conditions. Description of Effects in Hazard Impact Area The vulnerability of the pipeline to landslide displacement is based on a strain analysis, case histories, and professional judgement. The slide length along the pipeline has been used to differentiate the vulnerability to earth landslides in this assessment. Vulnerability values are Table A-5 – Vulnerability Values Based on the Slide Length Along the Pipeline summarized in Table A-5 if for Landslides. the pipeline is in the initiation V(i) or transport zone. Vulnerability Slide Length (m) Values Use V = 0.001 if the pipeline is in the landslide runout <150 0.01 zone. 150 - 300 0.1 >300 0.5

Examples of Potential Mitigation Options Set I = 0 if grading the RoW Options to Reduce Frequency grading removes the 1. Use grading to remove the hazard for small, shallow, hazard. landslides that are located on the RoW. Grading is not Use MF = 0.01 to 0.9 for applicable for larger earth landslides or areas outside the grading the RoW, or RoW. installing groundwater and 2. Dewatering/drainage, erosion protection, or groundwater surface water control, or and surface water management, although for very large install a toe berm. areas these measures may not be practical. Re-calculate the FLOC Options to Reduce the Hazard Horizontally Reaching the Centerline based on revised pipeline location. 1. Relocate the pipeline to increase the distance between the geohazard and the pipeline. Use MSV = 0.2 to 0.8 for increasing the soil depth of Options to Reduce the Hazard Vertically Reaching the Pipeline cover if the pipe is in the 1. Use shallower burial to reduce the stresses associated with deposition zone or reducing soil-structure interaction during landslide movement or the burial depth if the pipe is increase the burial depth if the pipeline is in the deposition in the main body of the M(i) zone. landslide. 2. Increase the depth of cover with trenchless methods to Use MSV = 0.001 to 0.1 if install the pipeline below the failure surface. trenchless methods are Options to Reduce Vulnerability used to install the pipeline below the failure surface. 1. Install heavy wall pipe. Use MV = 0.8 for 14.7 mm 2. Install low friction coating or a geotextile wrap to reduce pipe and MV = 0.6 for loading on the pipeline due to ground movements if the 19 mm pipe. pipeline is in the initiation or transport zone and ground movements are parallel or oblique to the pipeline. Use MV = 0.2 to 0.8 for installing low friction 3. Re-orient the pipeline down the slope or remove the micro- coating. bends on the slope if the pipeline is in the initiation or transport zone. Use MV = 0.05 to 1 for re- orientating the pipe parallel 4. Install soft/loose/low density backfill to reduce the loading on to the slope movements or the pipeline due to ground movement if the pipeline is in the removing micro-bends on initiation or transport zone. the slope. 5. Install expansion loops or place the pipeline above ground. Use MV = 0.1 to 0.9 if the 6. Install high strain capacity pipe. trench is backfilled with

7. Ongoing monitoring and site specific inspections to identify, soft/loose/low density respond, and manage landslides. backfill.

Use MV = 0.01 to 0.1 if At locations where multiple types of mitigation are proposed, a lower expansion loops are limit was set at 0.01 for the cumulative mitigation value except for sites installed or the pipe is where the pipe will be installed with trenchless methods. placed on the ground surface.

Use MV = 0.1 to 0.9 for high strain capacity pipe.

Use MV = 0.1 to 0.5 for ongoing monitoring to identify and manage landslides.

Table A – 6 HYDROTECHNICAL HAZARD: DEBRIS FLOW

General Process Description Debris flows are extremely rapid down slope movements of a saturated mixture of soil, rock, organic debris, and water within a channel. They are highly erosive in the initiation and transport reaches and can impart greater impact forces due to their ability to transport larger boulders at higher velocities than floods or debris floods. The watery tail of a debris flow can expose the pipe leaving it vulnerable to future debris-flow impacts. Required Conditions for Geohazard 1. Stream channels with average channel gradients exceeding approximately 15°. 2. Steep rock or soil slopes along the upstream valley walls or within the drainage basin. 3. Intense rainfall with sufficient antecedent moisture conditions. 4. Potential of side slope failures to impact main channel and transfer momentum. Geohazard Assessment Data Sources 1. Surficial geology terrain mapping. 2. Air photograph interpretation. 3. River Network Tool that contains stream crossing locations and historical as well as real-time hydrometric data. 4. Slope angle map based on a LiDAR survey. 5. Google EarthTM imagery. 6. Site observations, published information on regional occurrences, corporate history, and/or industry experience. Triggering Mechanisms Debris flows are typically triggered by exceedance of a rainfall threshold with sufficient antecedent moisture conditions resulting in a discrete slope instability or mobilization of channel bed sediments. Debris flows can also be triggered by changes in overland surface water flow and the breaching of naturally or artificially dammed streams or lakes. Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria for Channels 1. Evidence of a debris-flow hazard identified in the terrain mapping, desktop study, or the field investigation. 2. Presence of an active or inactive channel identified in the 1.0 = Credible (meets some LiDAR topography that crosses the pipeline with a channel or all the screening criteria). gradient greater than 3 degrees. I(i)

0 = Not credible (does not Occurrence Screening Criteria for Unchanneled Fan Surfaces meet the screening criteria). 1. Evidence of a debris-flow hazard identified on the fan surface from the terrain mapping, desktop study, or the field investigation.

The F(i) for each channel and fan surface was assigned a frequency class that represents a range of the debris flow frequency. Use F = 0.1 – 0.03 for easily visible levee or boulder deposits on fans, unvegetated main channels with multiple feeder channels in the transport zone, and ample debris supply sources in the initiation zone. Description of Frequency Use F = 0.03 – 0.01 for The frequency of occurrence was estimated for existing channels in visible levee or boulder the initiation, transport, and fan zones, and for unchanneled fan deposits on fans, partially surfaces. vegetated main channels Debris-flow frequency is estimated based on visual indicators such as with several feeder channels vegetation cover and age, over bank deposits, and presence of F(i) in the transport zone, and historical debris-flow lobes or levees on alluvial fans or colluvial some debris supply sources cones. in the initiation zone. TM Google Earth imagery, LiDAR topography, air photograph Use F = 0.01 – 0.003 for interpretation and field observations were used to evaluate the poorly identifiable levee or frequency of debris flows within channels and across fans that cross boulder deposits on fans, the pipeline. vegetated main channels in the transport zone, and few debris supply sources in the initiation zone. Use F = 0.003 – 0.001 if it is very difficult to identify any evidence of debris flows on fans, stable channel in the transport zone, and debris supply sources are rare in the initiation zone.

The average F(i) value for each frequency class is used to estimate the FLoC. Potential for Hazard to Horizontally Reach the Centerline This factor is the conditional probability that the debris flow will reach SH(i) the pipeline centerline if the debris-flow event occurs. It is assumed Use SH = 1. that the debris flow will reach the centerline if the channel or fan crosses the pipeline. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability for a debris flow to scour through the depth of cover and expose the pipeline if a debris flow occurs and the channel crosses the pipeline. Debris flows are highly The SV for each channel and erosive in the initiation and transport zones. On fan surfaces, debris fan surface ranges from flows are typically depositional, however, the watery tail of a debris 0.001 to 0.99; except where SV(i) flow, or a debris flood or flood between debris-flow events may expose the pipeline is to be buried in the pipe to future impacts. a bedrock trench, in which Two methods are used to estimate the probability of scour to the case SV = 0. pipeline from a debris flow. The two methods consist of a stochastic analysis of the fan and channel surfaces and a deterministic analysis of channel geometry and erodibility. The method that results in a greater probability of scour is used to estimate the FLoC.

Description of Potential Effects in Hazard Impact Area The vulnerability of the pipeline is the conditional probability that a debris flow causes loss of containment, if a debris flow occurs and exposes the pipeline. The vulnerability of the pipeline to debris flows depends on whether a boulder of sufficient size and velocity or the concentrated loading of the debris-flow material on the exposed pipe is greater than the resistance of the pipe leading to a loss of containment. The vulnerability of the pipeline is estimated based on debris-flow parameters such as; flow velocity, maximum transported boulder size, flow depth, flow density, maximum exposure length of the pipe across the channel, and whether the pipeline is partially or fully exposed. Partial pipe exposures are prone to boulder impacts, whereas a fully exposed pipe is subjected to both boulder impacts and concentrated loading by the debris-flow material. Debris-flow vulnerability values for a partially and V(i) Table A-6 - Vulnerability Values Based on Bankfull Width and Flow Velocity for fully exposed pipe are Debris Flows. summarized in Table A-6. Loading Scenario Partially Fully Exposed Exposed Pipe Pipe Bankfull width > 5 m and flow 0.02 0.1 velocity > 5 m/s Bankfull width < 5 m or flow 0.01 0.05 velocity < 5 m/s Bankfull width < 5 m and flow 0.005 0.025 velocity < 5 m/s If Dmax < 1 for all bankfull widths 0.002 Classified as and flow velocities above.

Example of Potential Mitigation Options Re-calculate the FLOC based on revised pipeline Options to Reduce Frequency location. 1. Not applicable. Use MSH = 0.1 to 0.9 for the Options to Reduce the Hazard Horizontally Reaching the Centerline construction of a debris flow 1. Relocate the pipeline on the margins of the fan or floodplain. retention structure located upstream of the crossing. 2. Build a debris-flow retention structure upstream of the pipeline crossing. Use MSH = 0.05 to 0.5 for channel training to reduce 3. Train the channel to reduce the likelihood of avulsion on the the likelihood of avulsion. fan. Re-calculate the FLOC Options to Reduce the Hazard Vertically Reaching the Pipeline M(i) based on the new SV value 1. Install the sag and over bends below the design scour level calculated from the revised through the existing channel and through the entire the pipeline depth of cover. fan/floodplain. Use MSV = 0.05 to 0.5 for 2. Install rip rap, engineered slope control structure, steel the installation of rip rap, an plates, and/or concrete covers to decrease the scour engineering slope control potential within the channel. structure, or concrete Options to Reduce Vulnerability covers. 1. Install heavy wall pipe. Use MV = 0.8 for 14.7 mm 2. Install concrete coated pipe. pipe and MV = 0.6 for 19 mm pipe for impact loading.

At locations where multiple types of mitigation are proposed, a lower Use Mv = 0.64 for 14.7 mm limit was set at 0.01 for the cumulative mitigation value except for sites pipe and Mv = 0.36 for where the pipe will be installed with trenchless methods. 19 mm pipe for hydrodynamic loading.

Use MV = 0.1 to 0.9 for installing concrete coated pipe.

Table A – 7 HYDROTECHNICAL HAZARD: DEBRIS FLOOD

General Process Description A very rapid surging flow of water and sediment within an established channel. Debris floods are an intermediate channel process between clear water floods and debris flows and can significantly scour channels. Debris floods have a lower sediment concentration than debris flows and do not transport large material as suspended sediment but rather as bedload material. Required Conditions for Geohazard (do not all have to be fulfilled) 1. Steep stream channels typically between 3 and 15 degrees average gradient. 2. Erodible sediment along channel banks and channel bed. 3. Potential sources of instability such as landslide dams, beaver dams, man-made dams, and rockslide scars. Geohazard Assessment Data Sources 1. Surficial geology terrain mapping. 2. Air photograph interpretation. 3. River Network Tool that contains stream crossing locations and historical as well as real-time hydrometric data. 4. Slope angle map based on a LIDAR survey. 5. Google EarthTM imagery. 6. Site observations, published information on regional occurrences, corporate history, and/or industry experience. Triggering Mechanisms Debris floods are often initiated during flooding events where sediment is entrained due to erosion or when landslides deposit in flood waters. Debris floods can be triggered following intense precipitation, glacier-outburst or lake floods, and the mobilization of discrete or multiple landslide sources coincident with flooding. Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria for Channels 1. Evidence of a debris-flood hazard identified in the terrain mapping, desktop study, or the field investigation. 2. Presence of an active or inactive channel identified in the 1.0 = Credible (meets some or LiDAR survey that crosses the pipeline with a channel all the screening criteria). gradient greater than 3 degrees but less than 15 degrees. I(i) Occurrence Screening Criteria for Unchanneled Fan Surfaces 0 = Not credible (does not meet the screening criteria). 1. Evidence of a debris-flood hazard identified on the fan surface from the terrain mapping, desktop study, or the field investigation.

The F(i) for each channel and fan surface was assigned a Description of Frequency frequency class that represents a range of the debris flood The frequency of occurrence was estimated for existing channels in frequency. the initiation, transport, and fan zones, and for channelized fan surfaces. Use F = 0.1 – 0.03 for easily visible levee or boulder deposits Debris-flood frequency is estimated based on visual indicators such on fans, unvegetated main F(i) as vegetation cover and age, over bank deposits, and presence of channels with multiple feeder historical debris-flood deposits on alluvial fans. channels in the transport zone, TM Google Earth imagery, LiDAR topography, air photograph and ample debris supply interpretation and field observations were used to evaluate the sources in the initiation zone. frequency of debris floods within channels and fans that cross the Use F = 0.03 – 0.01 for visible pipeline. levee or boulder deposits on fans, partially vegetated main channels with several feeder

channels in the transport zone, and some debris supply sources in the initiation zone. Use F = 0.01 – 0.003 for poorly identifiable levee or boulder deposits on fans, vegetated main channels in the transport zone, and few debris supply sources in the initiation zone. Use F = 0.003 – 0.001 if it is very difficult to identify any evidence of debris floods on fans, stable channel in the transport zone, and debris supply sources are rare in the initiation zone.

The average F(i) value for each frequency class is used to estimate the FLoC Potential for Hazard to Horizontally Reach the Centerline This factor is the conditional probability that the debris flood will reach SH(i) the pipeline centerline if the debris-flood event occurs. It is assumed Use SH = 1. that the debris flood will reach the centerline if the pipeline crosses the channel or the fan. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability for a debris flood to scour through the depth of cover and expose the pipeline if a debris flood The SV for each channel and fan occurs and the channel crosses the pipeline. Debris floods are highly surface ranges from 0.001 to erosive in the initiation and transport zones as well as on fan surfaces. SV(i) 0.99; except where the pipeline Two methods were used to estimate the probability of scour to the is to be buried in a bedrock pipeline from a debris flood. The two methods consist of a stochastic trench, in which case SV = 0. analysis of the fan and channel surfaces and a deterministic analysis of channel geometry and erodibility. The method that resulted in a greater probability of scour was used to estimate the FLoC. Description of Potential Effects in Hazard Impact Area The vulnerability of the pipeline is the conditional probability that a debris flood causes loss of containment if a debris flood occurs and exposes the pipeline. The vulnerability of the pipeline to debris floods depends on whether a boulder of sufficient size and velocity or the concentrated loading of the debris-flood material on the exposed pipe is greater than the resistance of the pipe leading to a loss of containment. The vulnerability of the pipeline is estimated based on variables describing flow velocity, maximum transported boulder size, flow Debris-flood vulnerability values depth, flow density, maximum exposure length of the pipe across the for a partially and fully exposed V(i) channel, and whether the pipeline is partially or fully exposed. Partial pipe are summarized in pipe exposures are prone to boulder impacts, whereas a fully exposed Table A-7. pipe is subjected to both boulder impacts and concentrated loading by the debris-flood material. Table A-7 - Vulnerability Values Based on Bankfull Width and Flow Velocity for Debris Floods.

Loading Scenario Partially Fully Exposed Exposed Pipe Pipe Bankfull width > 5 m and flow 0.01 0.05 velocity > 5 m/s Bankfull width < 5 m or flow 0.005 0.025 velocity < 5 m/s Bankfull width < 5 m and flow 0.0001 0.0001 velocity < 5 m/s

Re-calculate the FLOC based Example of Potential Mitigation Options on revised pipeline location. Options to Reduce Frequency Use MSH = 0.05 to 0.5 for the 1. Not applicable. construction of a debris flow Options to Reduce the Hazard Horizontally Reaching the Centerline retention structure located upstream of the crossing. 1. Relocate the pipeline on the margins of the fan or floodplain. Use MSH = 0.1 to 0.9 for 2. Build a debris flood retention structure upstream of the channel training to reduce the pipeline crossing. likelihood of avulsion. 3. Train the channel to reduce the likelihood of avulsion on the Re-calculate the FLOC based fan. on the new SV value calculated Options to Reduce the Hazard Vertically Reaching the Pipeline from the revised the pipeline 1. Install the sag and over bends below the design scour level depth of cover. M(i) through the existing channel and through the entire Use MSV = 0.05 to 0.5 for the fan/floodplain. installation of rip rap, an 2. Install rip rap, engineered slope control structure, steel engineering slope control plates, and/or concrete covers to decrease the scour structure, or concrete covers. potential within the channel. Use MV = 0.8 for 14.7 mm pipe Options to Reduce Vulnerability and MV = 0.6 for 19 mm pipe for 1. Install heavy wall pipe. impact loading. 2. Install concrete coated pipe. Use Mv = 0.64 for 14.7 mm pipe and Mv = 0.36 for 19 mm pipe for hydrodynamic loading. At locations where multiple types of mitigation are proposed, a lower Use MV = 0.1 to 0.9 for limit was set at 0.01 for the cumulative mitigation value except for sites installing concrete coated pipe. where the pipe will be installed with trenchless methods.

Table A – 8 HYDROTECHNICAL HAZARD: SCOUR

General Process Description Scour is the vertical erosion of sediment from the bed of an active stream channel during a flood event. There are two types of scour: general scour and local scour. General scour is the natural variation in bed levels that occurs due to the complex interaction between discharge, sediment transport, and channel morphology. Local scour occurs from acceleration of flow due to an obstruction or constriction to flow near piers, abutments, large woody debris, or other structures, like at the confluence of two separate channels. Although less typical, scour can also occur on floodplains during flooding.

Required Conditions for Geohazard 1. All stream channels except channels in bedrock. 2. Stream bed material that can be mobilized by flood flows. 3. Stream channels that are prone to flooding.

Geohazard Assessment Data Sources 1. Surficial geology terrain mapping based on Air Photograph Interpretation. 2. NRCan CANVEC stream crossing locations. 3. Slope angle map based on LIDAR. 4. Google EarthTM imagery. 5. Site observations, published information on regional occurrences, corporate history, and/or industry experience.

Geohazard Triggering Mechanisms Scour is triggered by high discharge in response to high rainfall, snowmelt or a combination thereof. Scour can be exacerbated when the direction of flow is changed at channel bends, confluences, constrictions, and obstructions, the latter of which can be both anthropogenic and naturally occurring. Less frequently, scour can also occur on floodplains inundated by overbank flood waters.

Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. Stream channels that contain erodible bed materials such as clay, silt, sand, gravels, and cobbles, and discharge great 1.0 = Credible (meets some enough to mobilize bed material. or all the screening criteria). I(i) 2. Stream channels that have the potential to scour and expose 0 = Not credible (does not the pipeline. meet the screening criteria). 3. Areas mapped as a fluvial plain identified with a flooding hazard in the terrain mapping. Description of Frequency Failures of buried pipelines at stream crossings are caused by three primary failure modes: vortex induced vibration (VIV), dynamic For impact loading, use F = pressure, and denting by impact loading (Ferris et al. 2015). The 0.005 (200-year return) to frequency of each failure mode depends on the frequency of a flood expose the crown of the pipe scouring and exposing a critical section of pipeline. at the watercourse crossing. For VIV and dynamic F(i) The frequency for exposing a critical section of the pipeline is estimated with a scour assessment based on the discharge pressure, use F = associated with a specific flood return period. For impact loading to 0.005

In agreement with the provincial guidelines, exposure of the crown by a 200-year flood event shall be prevented (AESRD 2013; BC MOE 1999)

Potential for Hazard to Horizontally Reach the Centerline This factor is the conditional probability that scour will reach the Use SH = 1 if the pipeline pipeline centerline if the flooding event occurs. crosses the stream. SH(i) It has been assumed that scour will reach the centerline if the pipeline Use SH = 0.1 if the pipeline crosses the stream channel. If the pipeline is within the floodplain and crosses the floodplain. does not cross the channel, a reduce horizontal spatial has been assumed. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that scour will remove the cover and expose the pipeline given the stream channel reaches the pipeline and the flooding event occurs. SV(i) Use SV = 1. The vertical spatial factor is a function of the return period for exposing the critical section of pipeline during a flooding event. The value is set at 1 as the scouring and exposing the critical section of the pipeline is addressed in the Frequency term. Description of Effects in Hazard Impact Area The vulnerability of an exposed pipeline at a stream crossing depends on whether an unsupported free span occurs resulting in vortex induced vibration (VIV), dynamic pressure, or the energy from a boulder of sufficient size and velocity that impacts the exposed pipe is greater than the resistance of the pipe leading to a loss of containment. A minimum free span length of approximately 25 m is required to initiate VIV and for a dynamic pressure to be a credible hazard (Dooley et al. 2014). VIV, dynamic pressure, and impact loading failure mechanisms are evaluated for creeks greater than 20 m to account for the increase in free span length to bankfull width associated with greater flood return periods (Ferris et al. 2015). For creeks less than 20 m, only the impact loading failure mechanism is assessed. The greater estimated FLoC is presented regardless of the Vulnerability values within failure mechanism. stream channels for VIV, dynamic pressure, and Based on empirical relationships from case histories impact loading are V(i) (Dooley et al. 2014), bankfull width, and the average channel gradient summarized in Table A-8a, have been used as a proxy for the vulnerability of the pipeline for a Table A-8b, and Table A-8c. VIV failure. Use V = 0.001, if the pipe is Table A-8a - Vulnerability Values Based on Bankfull Width and Channel located on the floodplain. Gradient for VIV Failure.

>250 0.06 0.2 0.5 Bankfull 100-250 0.03 0.1 0.2 Width (m) 50-100 0.01 0.05 0.1 20-50 0.006 0.02 0.05 < 2 2 – 10 >10 Bankfull Width ~> 20 m Channel Gradient (%)

Dynamic pressure loading is estimated by the free span length, flow velocity, and fluid density. The vulnerability of the pipe to dynamic pressure has been estimated with a stochastic simulation by relating the force generated by the stream flow to the maximum resistance force of the pipe. The bankfull width and the stream velocity have

been used as a proxy for the vulnerability of the pipeline for dynamic pressure. Table A-8b - Vulnerability Values Based on Bankfull Width and Stream Velocity for Dynamic Pressure. >250 0.1 0.5 0.9 Bankfull 100-250 0.01 0.1 0.5 Width (m) 50-100 0.001 0.01 0.1 20-50 0.0001 0.001 0.01 < 5 5 – 6 >6 Bankfull Width ~> 20 m Stream Velocity (m/s)

Impact loading is estimated by the boulder mass and the boulder velocity. The vulnerability of the pipe to impacts has been estimated with a stochastic simulation by relating the impact energy of a moving boulder in the stream to the maximum allowable impact energy of the pipe. The boulder diameter and the stream velocity have been used as proxy for the vulnerability of the pipeline from impacts.

Table A-8c - Vulnerability Values Based on Boulder Diameter and Stream Velocity for an Impact Failure by Denting. >2.5 0.001 0.005 0.01 Boulder 2.0 – 2.5 0.0005 0.001 0.005 Diameter (m) 1.5 – 2.0 0.0001 0.0005 0.001 <1.5 0.00001 0.00005 0.0001 < 5 5 – 6 >6 All bankfull widths Stream Velocity (m/s)

The vulnerability of the pipeline to scour on the floodplain depends on the ability of the flood to erode the overlying material and expose the pipeline. A value of 0.001 has been used as the vulnerability for flooding based on the assumed erosion potential of the material overlying the pipeline.

Example of Potential Mitigation Options Set I = 0 if the pipe is re- Options to Reduce Frequency located so it does not cross 1. Not applicable. the stream. Options to Reduce the Hazard Horizontally Reaching the Centerline Re-calculate the FLOC 1. Relocated the pipeline so the stream does not cross the based on revised pipeline channel. depth of cover. Options to Reduce the Hazard Vertically Reaching the Pipeline Use MSV = 0.001 to 0.1 if trenchless methods are 1. Install the pipeline sag and over bends below the design used to increase the depth scour level through the channel and through the entire of cover. M(i) fan/floodplain. Re-calculate the FLOC 2. Increase the depth of cover with trenchless methods. based on revised rip rap 3. Install channel lining materials riprap to reduce the likelihood diameter in the channel of scour. bed. 4. Install or concrete covers, steel casing, or grout matts to Use MSV = 0.05 to 0.5 for reduce the likelihood of scour. the installation of concrete covers, steel casings, or 5. Install concrete weirs or slope control structures. grout matts.

Options to Reduce Vulnerability Use MSV = 0.1 to 0.7 for the installation of concrete 1. Use heavier wall pipe.

2. Install concrete coated pipe (applicable to the VIV failure weirs or slope control mode). structures.

Use MV = 0.8 for 14.7 mm At locations where multiple types of mitigation are proposed, a lower pipe and MV = 0.6 for limit was set at 0.01 for the cumulative mitigation value except for sites 19 mm pipe for impact where the pipe will be installed with trenchless methods. loading. Use Mv = 0.64 for 14.7 mm pipe and Mv = 0.36 for 19 mm pipe for hydrodynamic loading. Use Mv = 1 for both 14.7 mm and 19 mm pipe for VIV.

Use MV = 0.5 to 0.9 for installing concrete coated pipe.

Table A – 9 HYDROTECHNICAL HAZARD: AVULSION

General Process Description Avulsion is a process where stream flow from an established channel is transferred to an adjacent, usually lower elevation terrain. Avulsion is predominantly a concern on alluvial fans that carry high bed material loads. However, in this analysis, avulsion also refers to increased flows into an existing side channel or abandoned channel, eventually resulting in the abandonment of the main channel. For the latter scenario, avulsion typically occurs progressively over a period of years rather than suddenly during a large flood event (although the large flood event may be the final tipping point for the avulsion to occur). Avulsion can also occur in low gradient, meandering streams through the development of a chute channel across a tortuous meander bend.

Required Conditions for Geohazard 1. Unstable stream channel within an alluvial fan system with minimal lateral confinement. 2. Stable stream channels that are blocked from an external source. 3. Existing side channels or abandoned channels that are only inundated during peak flow events. 4. Tortuous meander bend. 5. Triggering event such as a flood, which exceeds bankfull conditions.

Geohazard Assessment Data Sources 1. Surficial geology terrain mapping based on air photograph Interpretation. 2. NRCan CANVEC stream crossing locations. 3. Slope angle map based on LIDAR. 4. Google EarthTM imagery. 5. Site observations, published information on regional occurrences, corporate history, and/or industry experience.

Triggering Mechanisms Avulsion is usually triggered by high flood flows that mobilize significant sediment. Avulsion may also be triggered by the damming of streams from debris flows, ice jams, or avalanches. These triggering mechanisms other than high flood flows are accounted for in the assessment of debris flows and debris floods.

Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. Low stability stream channels (multiple channels) situated on an alluvial plain or fan system where the stream channel is not laterally constrained. 1.0 = Credible (meets some 2. Stream channel with high bed load supply. or all the screening criteria). I(i) 3. Streams that cross colluvial cones or fluvial fans. 0 = Not credible (does not 4. Tortuous meander bend in an unconfined river. meet the screening criteria). 5. Potential source of external blockage such as avalanche deposits, woody debris, or debris flows for high stability streams. Description of Frequency The pipeline failure modes presented for scour are applicable to the avulsion hazard. The frequency of each failure mode depends on the frequency of avulsion at a stream channel that exposes a critical section of pipeline. Use F = varies for each stream crossing based on a F(i) The frequency of avulsion depends on the whether the stream site-specific avulsion channel overtops the banks and forms a new channel during a flood assessment. event or because of channel blockage. Potential channel obstructions as large woody debris, stream morphology, and presence of a floodplain, stream flow velocity, bank material, and the number of side channels influence the likelihood of avulsion at a stream crossing. The frequency of avulsion is estimated by calculating the flood return

period that overtops the stream channel banks and modifying the frequency to account for site specific channel characteristics that influence the frequency of avulsion.

Potential for Hazard to Horizontally Reach the Centerline Use SH = 1 if the pipeline is This factor is the conditional probability that avulsion will reach the within the floodplain and SH(i) pipeline centerline if avulsion occurs. perpendicular to the stream It has been assumed that avulsion will reach the centerline if the channel. pipeline crosses perpendicular to the stream channel.

Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that the depth of cover will be removed by avulsion and the pipeline will be exposed given the Use SV = 1 if the crown of the stream channel reaches the pipeline and the avulsion event occurs. pipe across the floodplain is The pipeline has a greater likelihood of becoming exposed to a critical at a higher elevation than the main stream channel. SV(i) length due to incision and scour of the avulsion channel if the pipe is buried at an elevation greater than the elevation of the thalweg of the Use Sv = varies based on main channel. A reduced spatial factor is used when the crown of the the elevation of the pipe pipe is at an elevation equal to the burial elevation at the main stream relative to the elevation of channel. The frequency to scour and expose the pipeline has been the thalweg. used to estimate the vertical spatial factor when the pipeline is buried with the same burial elevation at the main stream channel. Description of Effects in Hazard Impact Area The vulnerability values for the pipeline for the loss of containment from avulsion are based on the similar processes and failure mechanisms for scour and thus, share the same values. The vulnerability of an exposed pipeline at a stream crossing depends on whether an unsupported free span occurs resulting in VIV, dynamic pressure, or the energy from a boulder of sufficient size and velocity impacts the exposed pipe is greater than the resistance of the pipe leading to a loss of containment. A minimum free span length of approximately 25 m is required to initiate VIV and for a dynamic pressure to be a credible hazard (Dooley et al. 2014). VIV, dynamic pressure, and impact loading failure mechanisms are evaluated for creeks greater than Vulnerability values within approximately 20 m to account for the increase in free span length to stream channels for VIV, bankfull width associated with greater flood return periods dynamic pressure, and impact loading are V(i) (Ferris et al. 2015). For creeks less than 20 m, only the impact loading failure mechanism is assessed. The greater estimated FLoC summarized in Table A-9a, is presented regardless of the failure mechanism. Table A-9b, and Table A-9c. Use V = 0.001, if the pipe is Based on empirical relationships from case histories located on the floodplain. (Dooley et al. 2014), bankfull width and the average channel gradient have been used as a proxy for the vulnerability of the pipeline for a VIV failure. Table A-9a - Vulnerability Values Based on Bankfull Width and Channel Gradient for VIV Failure.

>250 0.06 0.2 0.5 Bankfull 100-250 0.03 0.1 0.2 Width (m) 50-100 0.01 0.05 0.1 20-50 0.006 0.02 0.05 < 2 2 – 10 >10 Channel Width ~> 20 m Channel Gradient (%)

Table A-9b - Vulnerability Values Based on Bankfull Width and Stream Velocity for Dynamic Pressure. >250 0.1 0.5 0.9 Bankfull 100-250 0.01 0.1 0.5 Width (m) 50-100 0.001 0.01 0.1 20-50 0.0001 0.001 0.01 < 5 5 – 6 >6 Channel Width ~> 20 m Stream Velocity (m/s)

Table A-9c - Vulnerability Values Based on Boulder Diameter and Stream Velocity for an Impact Failure by Denting. >2.5 0.001 0.005 0.01 Boulder 2.0 – 2.5 0.0005 0.001 0.005 Diameter (m) 1.5 – 2.0 0.0001 0.0005 0.001 <1.5 0.00001 0.00005 0.0001 < 5 5 – 6 >6 All channel widths Stream Velocity (m/s)

Example of Potential Mitigation Options Set I = 0 if the pipe is re- Options to Reduce Frequency located off the floodplain. 1. Not applicable. Re-calculate the FLOC scour potential if the sag Options to Reduce the Hazard Horizontally Reaching the Centerline and over bends are at or 1. Relocated the pipeline so the pipeline is not located within below the design scour the floodplain. level through the existing Options to Reduce the Hazard Vertically Reaching the Pipeline channel. Use MSV = 0.001 to 0.1 if M(i) 1. Install the pipeline sag and over bends below the design scour level through the existing channel and through the trenchless methods are entire fan/floodplain. used to increase the depth of cover. 2. Increase the depth of cover with trenchless methods. Re-calculate the FLOC 3. Install channel lining materials riprap to reduce the likelihood based on revised rip rap of scour. diameter in the avulsion 4. Install or concrete covers, steel casing, or grout matts to channels.

reduce the likelihood of scour. Use MSV = 0.05 to 0.5 for 5. Install concrete weirs or slope control structures. the installation of concrete

Options to Reduce Vulnerability covers, steel casings, or grout matts. 1. Use heavier wall pipe. Use MSV = 0.1 to 0.7 for the 2. Install concrete coated pipe (applicable to the VIV failure installation of concrete mode). weirs or slope control structures.

At locations where multiple types of mitigation are proposed, a lower Use MV = 0.8 for 14.7 mm limit was set at 0.01 for the cumulative mitigation value except for sites pipe and MV = 0.6 for where the pipe will be installed with trenchless methods. 19 mm pipe for impact loading. Use Mv = 0.64 for 14.7 mm pipe and Mv = 0.36 for 19 mm pipe for hydrodynamic loading. Use Mv = 1 for both 14.7 mm and 19 mm pipe for VIV loading.

Use MV = 0.5 to 0.8 for installing concrete coated pipe.

Table A - 10 HYDROTECHNICAL HAZARD: LATERAL EROSION

General Process Description Lateral erosion is the horizontal erosion of sediment along the banks of a stream. Lateral erosion is a normal stream process and can result in exposure of the sag bends and over bends of a pipeline. Lateral erosion most often occurs on the outer bends of meandering rivers and braided rivers. Rates of lateral erosion depend on the magnitude of flooding events, bank material, channel morphology, upstream sediment supply and presence of channel obstacles. Erosion can take place slowly over a period of years or suddenly during a single flood event. Lateral erosion also includes encroachment for stream channels that are located adjacent to the pipeline.

Required Conditions for Geohazard 1. Erodible stream channel bank material. 2. High flood flows that can erode the stream bank material.

Geohazard Assessment Data Sources 1. Surficial geology terrain mapping based on Air Photograph Interpretation. 2. NRCan CANVEC stream crossing locations. 3. Slope angle map based on LIDAR. 4. Google EarthTM imagery. 5. Historical aerial photographs. 6. Site observations, published information on regional occurrences, corporate history, and/or industry experience.

Triggering Mechanisms High flows following rainfall, snowmelt or a combination thereof increase the likelihood of lateral migration. Lateral migration is an ongoing process in natural stream channels and erosion rates can also be influenced by the presence of channel obstacles.

Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. A stream channel that shows evidence of lateral erosion or low stability streams consisting of meandering, braided, or anastomosing channels typically found on an alluvial plain or 1.0 = Credible (meets some fan system within the floodplain. or all the screening criteria). I(i) 2. Stream banks that contain erodible material such as clay, silt, sand, or gravels. 0 = Not credible (does not 3. Potential source of external blockage such as avalanche meet the screening criteria). deposits or debris flows for high stability streams. 4. A stream channel that is parallel to the pipeline alignment.

Description of Frequency The pipeline failure modes presented for scour are applicable to the lateral erosion hazard. The frequency of each failure mode depends on the frequency of lateral erosion at a stream channel that exposes a critical section of pipeline. Use F = varies for each Lateral erosion at river crossings occurs as progressive erosion in low stream crossing based on a F(i) energy environments over long time periods or as sudden erosion in site specific lateral erosion high energy environments over short time periods. The frequency of assessment. progressive erosion is estimated by relating the setback distance of the sag bends to the average lateral erosion rate. The frequency of sudden lateral erosion depends on whether lateral erosion occurs during a flooding event. Site specific characteristics such as channel steepness and the rooting depth of the vegetation

along the channel banks Influence the likelihood of lateral erosion at a stream crossing. A critical stream depth associated with a specific flood return period that mobilizes the material at the base of the channel bank is used to estimate the frequency of sudden lateral erosion. The critical stream depth is then used to estimate the potential widening of the stream channel for the specific flood return period. The frequency of lateral erosion exposing the pipeline is estimated by comparing the frequency necessary to widen the channel to the exposed the pipe at the sag bend for a given setback distance.

Potential for Hazard to Horizontally Reach the Centerline This factor is the conditional probability that lateral erosion will reach the pipeline centerline if lateral erosion occurs. The horizontal spatial factor is a function of the return period for Use SH = 1. SH(i) exposing the critical section of pipeline. The value is set at 1 as lateral erosion and exposing the critical section of the pipeline is addressed in the Frequency term. The lateral erosion hazard is mapped to the length of pipeline that is affected by the lateral erosion hazard. The encroachment hazard is mapped to the length of pipeline exposed to the encroachment hazard.

Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that the depth of cover will be removed by lateral erosion and the centerline will be exposed given the stream channel reaches the centerline and the lateral erosion SV = 1 if the crown of the event occurs. pipe across the floodplain is SV(i) The pipeline has a greater likelihood of becoming exposed to a critical at a higher elevation than length if the pipe is buried at a higher elevation along the river bank the main stream channel. and floodplain when compared to the elevation of the main stream channel. A reduced spatial factor is used when the crown of the pipe is at an elevation equal to the burial elevation at the main stream channel. Description of Effects in Hazard Impact Area The vulnerability values for the pipeline for the loss of containment from lateral erosion are based on the similar processes for scour and thus share the same values. A minimum free span length of approximately 25 m is required to initiate VIV and for a dynamic pressure to be a credible hazard Vulnerability values at (Dooley et al. 2014). VIV, dynamic pressure, and impact loading stream crossings for VIV, failure mechanisms are evaluated for creeks greater than 20 m to dynamic pressure, and account for the increase in free span length to bankfull width impact loading are associated with greater flood return periods (Ferris et al. 2015). For V(i) summarized in Table A-10a, creeks less than 20 m, only the impact loading failure mechanism is Table A-10b, and Table A- assessed. The greater estimated FLoC is presented regardless of the 10c. failure mechanism. Use V = 0.001, if the pipe is Based on empirical relationships from case histories located on the floodplain. (Dooley et al. 2014), bankfull width and the average channel gradient have been used as a proxy for the vulnerability of the pipeline for a VIV failure.

Table A-10a - Vulnerability Values Based on Bankfull Width and Channel Gradient for VIV Failure.

>250 0.06 0.2 0.5 Bankfull 100-250 0.03 0.1 0.2 Width (m) 50-100 0.01 0.05 0.1 20-50 0.006 0.02 0.05 < 2 2 – 10 >10 Channel Width ~> 20 m Channel Gradient (%)

Table A-10b - Vulnerability Values Based on Bankfull Width and Stream Velocity for Dynamic Pressure. >250 0.1 0.5 0.9 Bankfull 100-250 0.01 0.1 0.5 Width (m) 50-100 0.001 0.01 0.1 20-50 0.0001 0.001 0.01 < 5 5 – 6 >6 Channel Width ~> 20 m Stream Velocity (m/s)

Table A-10c - Vulnerability Values Based on Boulder Diameter and Stream Velocity for an Impact Failure by Denting. >2.5 0.001 0.005 0.01 Boulder 2.0 – 2.5 0.0005 0.001 0.005 Diameter (m) 1.5 – 2.0 0.0001 0.0005 0.001 <1.5 0.00001 0.00005 0.0001 < 5 5 – 6 >6 All channel widths

Stream Velocity (m/s) Example of Potential Mitigation Options Options to Reduce Frequency Re-calculate the FLOC 1. Not applicable. based on the new distance Options to Reduce the Hazard Horizontally Reaching the Centerline between the pipeline sag and over bends and the M(i) 1. Install the pipeline sag and over bends below the design channel banks. scour level through the existing channel and through the Re-calculate the FLOC entire fan/floodplain. based on revised rip rap 2. Install rip rap or grout matts along the channel banks. diameter along the channel 3. Install in channel flow control structures such as rock banks. groynes to train the channel away from the banks.

4. Ongoing monitoring and site specific inspections to Use MSH = 0.1 to 0.9 for the identify, respond, and manage lateral erosion. installation of in channel Options to Reduce the Hazard Vertically Reaching the Pipeline flow structures. 1. Install bank the pipeline sag and over bends below the Use MSH = 0.1 to 0.5 for design scour level through the existing channel and ongoing monitoring to through the entire fan/floodplain. identify and manage lateral erosion. 2. Increase the depth of cover with trenchless methods. Re-calculate the FLOC Options to Reduce Vulnerability based with Sv = 0.005 if the sag and over bends are at 1. Use heavier wall pipe. or below the design scour 2. Install concrete coated pipe (applicable to the VIV failure level through the existing mode). channel. Use MSV = 0.001 to 0.1 if trenchless methods are At locations where multiple types of mitigation are proposed, a lower used to increase the depth limit was set at 0.01 for the cumulative mitigation value except for sites of cover. where the pipe will be installed with trenchless methods. Use MV = 0.8 for 14.7 mm pipe and MV = 0.6 for 19 mm pipe for impact loading. Use Mv = 0.64 for 14.7 mm pipe and Mv = 0.36 for 19 mm pipe for hydrodynamic loading. Use Mv = 1 for both 14.7 mm and 19 mm pipe for VIV loading.

Use MV = 0.5 to 0.9 for installing concrete coated pipe.

Table A – 11 HYDROTECHNICAL HAZARD: OUTBURST-TYPE FLOODS

General Process Description A sudden, high volume and flow flood surge caused by the overtopping and/or breaching of a dam and the subsequent release of the impounded water. Outburst type floods are often associated with lakes dammed by glaciers, moraines, or landslide debris. The outburst of the flood can occur as a debris flow and transition to a debris flood. Required Conditions for Occurrence 1. Dammed body of water located upslope from the pipeline. 2. A channel or valley that extends from the dam to near the pipeline. Geohazard Assessment Data Sources 1. Surficial geology terrain mapping based on Air Photograph Interpretation. 2. Slope angle map based on LiDAR and a 1: 50 000 DEM. 3. Google EarthTM imagery. 4. Site observations, published information on regional occurrences, corporate history, and industry experience. Triggering Mechanisms Outburst floods are typically trigged by high precipitation events that overtop the dam causing erosion and potentially leading to internal piping resulting in a dam failure. Waves that are generated by landslides, rockfall, or ice avalanches into the impounded lake can overtop the dam causing erosion and dam failure. Some outburst floods are due to progressive weakening of the dam or failure can be seismically triggered. Guidance for Assigning Factor Considerations for Assigning Value to Each Factor Value to Factor Occurrence Screening Criteria 1. The pipeline is located downslope and downstream of a body of water impounded by a natural dam or that is below a potential landslide feature. 1.0 = Credible (meets some 2. The outlet channel from the body of water crosses or runs or all the screening criteria). parallel near the pipeline. I(i) 3. The body of water is not a sunken lake or dammed by competent bedrock. 0 = Not credible (does not meet the screening criteria). 4. The body of water is larger than 1 hectare in size. 5. The outbreak flood is expected to be noticeable and greater than the 200-year flood flow at the pipeline crossing. Description of Frequency Outburst floods have a low to moderate frequency and typically only occur once within the drainage basin unless a slope instability occurs into the impounded lake and the dam remains intact or the basin is dammed by a slope instability. Along the corridor, no outburst floods have occurred during operation Trans Mountain pipeline or in the existing literature (Clague & Evans 1994; Clague & Evans 2000; F(i) Use F = 0.001. McKillop & Clague 2006). Lakes were identified upslope of the pipeline and a frequency was assumed based on the desktop review by an expert of the: regional geology, site specific visible geological features, and potential for a slope instability entering the body of water. The return period for man- made dams was assumed as 1 in 1,000 years based on typical operation dam requirements.

Potential for Hazard to Horizontally Reach the Centerline This factor is the conditional probability that the outburst flood will reach the pipeline centerline given the outlet channel crosses the pipeline and the outburst event occurs. Use SH = 0.1, if outlet channel Outburst-generated debris flows have estimated travel distances of crosses the pipeline within the 10o from the outlet location (McKillop & Clague 2006). Debris floods maximum travel distance. H(i) S o may continue further downstream to 3 from the dam outlet assuming Use SH = 0.01, If outlet channel a continuous moderately steep channel gradient. For this crosses the pipeline outside the assessment, 3o was used for the maximum travel distance for outburst maximum travel distance. floods. The outburst-type flood hazard is mapped to a specified length of pipeline over which the outburst flood hazard exists. Potential for Hazard to Vertically Reach the Pipeline This factor is the conditional probability that the pipeline will become exposed by the outburst flood given the outlet channel reaches the SV(i) SV = 1. pipeline and the outburst flood event occurs. It is assumed that the pipeline will be exposed if the outburst flood occurs and reaches the pipeline. Description of Effects in Hazard Impact Area Use V = 0.1, if outlet channel or Outburst floods are extremely erosive events that can scour the outlet channel floodplain channel bed or cause significant lateral erosion. The vulnerability of crosses the pipeline. the pipeline to outburst floods is dependent on whether the flood can scour and expose the pipeline and the exposed pipeline is impacted The vulnerability value may be by a boulder of sufficient size to cause rupture, or expose a significant reduced by an order of magnitude if the outlet channel V(i) portion of the pipeline to cause a stress and vibration induced rupture. has many noted shallow On floodplains, the scour potential from outburst floods typically gradient sections and/or if the decreases as the flow from the outburst flood become unconfined. pipeline crossing point is The vulnerability has been reduced by an order of magnitude if the beyond the maximum travel pipeline is located outside the channel but within the floodplain. distance but is credible. The vulnerability values used in this assessment are based on Use V = 0.001 elsewhere. professional judgement.

Re-calculate the FLOC based Example of Potential Mitigation Options with SH = 0.01 if the pipe is Options to Reduce Frequency located beyond the maximum travel distance. 1. Not applicable. Use MSV = 0.1 to 0.5 if the Options to Reduce the Hazard Horizontally Reaching the Centerline pipeline sag and over bends 1. Locate the pipeline beyond the maximum travel distance. are located below the design Options to Reduce the Hazard Vertically Reaching the Pipeline scour level in the existing M(i) channel and through the entire 1. Install the pipeline sag and over bends below the design floodplain. scour level through the existing channel and through the entire fan/floodplain. Use MSV = 0.05 to 0.5 for the installation of engineered bed 2. Install engineered bed and bank protection. and bank protection. Options to Reduce Vulnerability Use MV = 0.8 for 14.7 mm pipe 1. Install heavier wall. and M = 0.6 for 19 mm pipe.

2. Install concrete coating. Use MV = 0.5 to 0.9 for installing concrete coated pipe.

APPENDIX B LIST OF GEOHAZARDS BY KP

Trans Mountain Attachment 1 Condition 16 Final BGC ENGINEERING INC. Geohazard List By KP Start

Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Mill Creek 12.73 12.74 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Mill Creek 12.73 12.74 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Lateral Erosion Blackmud Creek 24.17 24.21 1.0E+00 2.4E-03 1.0E+00 1.0E+00 6.0E-03 1.0E-05 7.0E-01 1.0E-05 (Encroachment)

Lateral Erosion Blackmud Creek 24.19 24.22 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Blackmud Creek 24.19 24.22 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Whitemud Creek 28.16 28.22 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Whitemud Creek 28.16 28.22 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) North Saskatchewan 33.48 33.68 1.0E+00 3.3E-03 1.0E+00 1.0E+00 3.0E-02 9.9E-05 1.0E-03 <1.0E-7 River

Lateral Erosion North Saskatchewan 33.48 33.68 1.0E+00 4.9E-03 1.0E+00 1.0E+00 3.0E-02 1.5E-04 1.0E-03 1.5E-07 (Bank Erosion) River

Scour (Flooding) North Saskatchewan 33.49 33.66 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07 River

Earth Landslide Wedgewood Creek 36.99 37.05 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-02 1.0E-06 East Slope - Edmonton

Scour (Local) Wedgwood Creek 37.1 37.14 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-04 <1.0E-7

Lateral Erosion Wedgwood Creek 37.1 37.14 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-04 <1.0E-7 (Bank Erosion)

Earth Landslide Wedgewood Creek 37.16 37.2 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-02 1.0E-06 West Slope - Edmonton

Scour (Local) Atim Creek 63.03 63.03 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Atim Creek 63.03 63.03 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Trib. to Atim Creek 64.31 64.31 1.0E+00 3.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Trib. to Atim Creek 65.51 65.52 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Kilini Creek 82.61 82.76 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Kilini Creek 82.67 82.72 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Kilini Creek 82.67 82.72 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Trib. to Wabamun Lake 95.55 95.55 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Page 1 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Earth Landslide Wabamum Lake North 107.47 107.61 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 Slope

Scour (Local) Trib. to Wabamun Lake 107.56 107.56 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Trib. to Wabamun Lake 107.91 107.91 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Trib. to Wabamun Lake 112.33 112.33 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Trib. to Wabamun Lake 113.72 113.73 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Magnolia Creek 125.11 125.15 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Local) Magnolia Creek 125.11 125.15 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Sturgeon River 125.81 126.03 1.0E+00 5.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Sturgeon River 125.81 126.03 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Flooding) Sturgeon River 125.82 125.92 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Sturgeon River 125.93 126.05 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Pembina River 133.99 134.06 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Pembina River 134.44 134.61 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-02 3.3E-05 1.0E-03 <1.0E-7

Lateral Erosion Pembina River 134.44 134.61 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-02 4.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Trib. To Lobstick River 135.96 135.96 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Trib. To Lobstick River 135.96 135.96 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Flooding) Zeb-Igler Creek 141.37 141.57 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Zeb-Igler Creek 141.51 141.55 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Zeb-Igler Creek 141.51 141.55 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Trib. To Lobstick River 144.99 144.99 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Local) Trib. To Lobstick River 144.99 144.99 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Trib. to Lobstick River 146.15 146.16 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 146.76 146.76 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Trib.to Chip Lake 151.02 151.05 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Local) Trib.to Chip Lake 151.02 151.05 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Scorpion East Creek 155.42 155.51 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Page 2 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Scorpion East Creek 155.46 155.47 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Trib.to Chip Lake 156.02 156.02 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Trib.to Chip Lake 156.02 156.02 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Trib.to Chip Lake 163.1 163.15 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Trib.to Chip Lake 163.1 163.15 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Trib.to Chip Lake 163.11 163.17 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Trib.to Chip Lake 167.23 167.24 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Trib.to Chip Lake 167.23 167.24 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Little Brule Creek 172.59 172.73 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Avulsion Little Brule Creek 172.63 172.69 1.0E+00 2.3E-01 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Little Brule Creek 172.63 172.69 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Little Brule Creek 172.63 172.69 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 177.88 177.93 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Unnamed Channel 177.88 177.93 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Brule Creek 179.88 180.05 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Avulsion Brule Creek 179.94 180.04 1.0E+00 2.3E-02 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Brule Creek 179.94 180.04 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Brule Creek 179.94 180.04 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Brule Creek 179.94 180.04 1.0E+00 2.4E-03 1.0E+00 1.0E+00 6.0E-03 1.0E-05 7.0E-01 1.0E-05 (Encroachment)

Scour (Flooding) Lobstick River 184.15 184.38 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Lobstick River 184.23 184.26 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Lobstick River 184.23 184.26 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Flooding) Carrot Creek 191.95 192.03 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Carrot Creek 192.01 192.03 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Carrot Creek 192.01 192.03 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 201.51 201.53 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) January Creek 205.95 205.99 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 3 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Lateral Erosion January Creek 205.95 205.99 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Avulsion Wolf Creek 219.14 219.46 1.0E+00 4.5E-03 1.0E+00 1.0E-04 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Wolf Creek 219.14 219.46 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Wolf Creek 219.14 219.46 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 1.0E-03 <1.0E-7

Scour (Flooding) Wolf Creek 219.15 219.82 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion McLeod River 222.57 222.79 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-01 4.9E-04 3.6E-04 1.8E-07 (Bank Erosion)

Scour (Local) McLeod River 222.57 222.79 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-01 3.3E-04 3.6E-04 1.2E-07

Scour (Flooding) McLeod River 222.68 222.79 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Bench Creek 226.35 226.45 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Bench Creek 226.39 226.44 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Bench Creek 226.39 226.44 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Scour (Local) Bench Creek 235.36 235.45 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Bench Creek 235.36 235.45 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Little Sundance 243.62 244.05 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Avulsion Little Sundance 243.94 244.04 1.0E+00 5.3E-02 1.0E+00 2.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Little Sundance 243.94 244.04 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Little Sundance 243.94 244.04 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Avulsion Sundance Creek 246.43 246.77 1.0E+00 1.1E-02 1.0E+00 2.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Sundance Creek 246.43 246.77 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Sundance Creek 246.43 246.77 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Flooding) Sundance Creek 246.46 246.78 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Unnamed Channel 256.4 256.4 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Flooding) Unnamed Channel 258.6 258.82 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Unnamed Channel 258.77 258.8 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Local) Unnamed Channel 258.77 258.8 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Sucker Creek 268.11 268.23 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Sucker Creek 268.18 268.24 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 4 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Lateral Erosion Sucker Creek 268.18 268.24 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Sucker Creek West 268.68 268.7 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Rooster Creek 290.44 290.44 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Ponoka Creek 293.88 293.89 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Ponoka Creek 293.88 293.89 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Earth Landslide Obed Mountain Road 297.07 297.21 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 East Slope - Hinton

Scour (Local) Roundcroft Creek 297.11 297.11 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Roundcroft Creek 297.11 297.11 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Lateral Erosion Sandstone Creek 301.01 301.03 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Sandstone Creek 301.01 301.03 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 303.25 303.27 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Hunt Creek 303.34 303.35 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Slides Trail Creek East 307.18 307.86 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 Slopes - Pedley

Scour (Local) Trail Creek 307.69 307.7 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Trail Creek 307.69 307.7 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Unnamed Channel 309.37 309.38 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 314.23 314.23 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Cache Percotte Creek 315.02 315.05 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Cache Percotte Creek 315.02 315.05 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Earth Landslide Hardisty Creek - Hinton 318.41 318.74 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-01 1.0E-05

Avulsion Hardisty Creek 318.59 318.64 1.0E+00 4.5E-02 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Hardisty Creek 318.59 318.64 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Hardisty Creek 318.59 318.64 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Happy Creek 321.78 321.79 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Maskuta Creek 326.05 326.22 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Maskuta Creek 326.05 326.22 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 5 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Avulsion Maskuta Creek 326.05 326.22 1.0E+00 5.3E-04 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Earth Landslide Unnamed Creek East 337.12 337.22 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 Slope

Rock Slide Klapperhorn 489.16 489.7 1.0E+00 4.2E-04 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 7.2E-01 <1.0E-7 Mountain - Mount Robson

Rock Avalanches Klapperhorn 489.16 491.73 1.0E+00 1.1E-04 5.0E-01 5.0E-01 1.0E+00 2.6E-05 1.0E+00 2.6E-05 Mountain - Mount Robson

Rockfall Klapperhorn 489.16 489.7 1.0E+00 1.0E-03 2.0E-01 5.0E-01 1.0E+00 1.0E-04 8.0E-02 8.0E-06 Mountain - Mt. Robson

Debris Flows Klapperhorn Channel 1 489.25 489.26 1.0E+00 5.5E-03 1.0E+00 2.4E-02 1.0E-02 1.3E-06 5.0E-01 6.7E-07

Debris Flows Klapperhorn Channel 2 489.35 489.37 1.0E+00 5.5E-03 1.0E+00 6.2E-03 5.0E-02 1.7E-06 4.1E-01 6.9E-07

Debris Flows Klapperhorn Fan 489.35 489.35 1.0E+00 1.7E-03 1.0E+00 4.3E-03 5.0E-02 3.8E-07 2.3E-01 <1.0E-7

Debris Flows Klapperhorn Fan 489.37 489.7 1.0E+00 1.7E-03 1.0E+00 4.3E-03 5.0E-02 3.8E-07 2.3E-01 <1.0E-7

Rock Slide Klapperhorn 489.7 490.83 1.0E+00 8.9E-04 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 1.0E+00 <1.0E-7 Mountain - Mount Robson

Debris Flows Klapperhorn Fan 489.7 489.87 1.0E+00 1.7E-03 1.0E+00 4.3E-03 5.0E-02 3.8E-07 5.8E-01 2.2E-07

Debris Flows Klapperhorn Channel 3 489.87 489.88 1.0E+00 1.7E-03 1.0E+00 1.2E-02 1.0E-02 2.0E-07 1.0E+00 2.0E-07

Debris Flows Klapperhorn Fan 489.88 490.08 1.0E+00 1.7E-03 1.0E+00 4.3E-03 5.0E-02 3.8E-07 5.8E-01 2.2E-07

Scour (Local) Baer Creek 490.08 490.09 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Baer Creek 490.08 490.09 1.0E+00 1.7E-02 1.0E+00 1.0E-01 5.0E-03 8.7E-06 6.4E-01 5.6E-06

Debris Flows Klapperhorn Fan 490.09 490.17 1.0E+00 1.7E-03 1.0E+00 4.3E-03 5.0E-02 3.8E-07 5.8E-01 2.2E-07

Debris Flows Marathon Creek Fan 490.72 490.76 1.0E+00 5.5E-03 1.0E+00 5.9E-03 5.0E-02 1.6E-06 5.8E-01 9.3E-07

Debris Flows Marathon Creek 490.76 490.78 1.0E+00 1.7E-02 1.0E+00 1.6E-02 1.0E-02 2.8E-06 1.0E+00 2.8E-06 Channel 1

Debris Flows Marathon Creek Fan 490.78 491.08 1.0E+00 5.5E-03 1.0E+00 5.9E-03 5.0E-02 1.6E-06 5.8E-01 9.3E-07

Debris Flows Marathon Creek 491.08 491.12 1.0E+00 5.5E-02 1.0E+00 1.0E-02 5.0E-02 2.8E-05 3.3E-01 9.0E-06

Lateral Erosion Marathon Creek 491.1 491.12 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Marathon Creek 491.1 491.12 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Marathon Creek Fan 491.12 491.17 1.0E+00 5.5E-03 1.0E+00 5.9E-03 5.0E-02 1.6E-06 5.8E-01 9.3E-07

Debris Flows Marathon Creek Fan 491.18 491.19 1.0E+00 5.5E-03 1.0E+00 5.9E-03 5.0E-02 1.6E-06 5.8E-01 9.3E-07

Page 6 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Unnamed Channel 491.19 491.2 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Marathon Creek 491.19 491.2 1.0E+00 1.7E-02 1.0E+00 2.0E-03 1.0E-02 3.5E-07 5.9E-02 <1.0E-7 Channel 2

Debris Flows Marathon Creek Fan 491.2 491.3 1.0E+00 5.5E-03 1.0E+00 5.9E-03 5.0E-02 1.6E-06 5.8E-01 9.3E-07

Debris Flows Marathon Creek Fan 491.32 491.87 1.0E+00 5.5E-03 1.0E+00 5.9E-03 5.0E-02 1.6E-06 1.0E+00 1.6E-06

Earth Landslide Fraser River East 493.07 493.56 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-01 1.0E-05 Slopes - Mt. Robson

Rock Avalanches Mount Terry Fox East 493.6 495.52 1.0E+00 8.0E-05 5.0E-01 1.0E-01 1.0E+00 4.0E-06 1.0E+00 4.0E-06 Slope - Mount Robson

Debris Flows Mt. Robson Fan 1 494.82 494.84 1.0E+00 1.7E-03 1.0E+00 1.4E-02 5.0E-02 1.2E-06 1.0E+00 1.2E-06

Debris Flows Mt. Robson Channel 1 494.84 494.84 1.0E+00 1.7E-03 1.0E+00 1.1E-02 5.0E-02 9.4E-07 1.0E+00 9.4E-07

Debris Flows Mt. Robson Fan 1 494.84 494.86 1.0E+00 1.7E-03 1.0E+00 1.4E-02 5.0E-02 1.2E-06 1.0E+00 1.2E-06

Debris Floods Terry Fox Creek 494.87 494.87 1.0E+00 1.7E-03 1.0E+00 2.2E-02 5.0E-02 1.9E-06 1.0E+00 1.9E-06

Scour (Local) Terry Fox Creek 495.18 495.45 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 8.0E-01 2.0E-07

Avulsion Terry Fox Creek 495.18 495.45 1.0E+00 4.0E-05 1.0E+00 5.0E-03 5.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Terry Fox Creek 495.18 495.45 1.0E+00 4.9E-03 1.0E+00 1.0E+00 5.0E-05 2.4E-07 8.0E-01 2.0E-07 (Bank Erosion)

Debris Floods Unnamed Channel 495.44 495.45 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-02 1.7E-06 1.0E-02 <1.0E-7

Rock Avalanches Mount Terry Fox 495.49 495.78 1.0E+00 1.0E-05 1.0E-01 5.0E-01 1.0E+00 6.0E-07 1.0E+00 6.0E-07 Middle Slope - Mount Robson

Rock Avalanches Mount Terry Fox West 495.78 497.92 1.0E+00 9.0E-05 5.0E-01 5.0E-01 1.0E+00 2.2E-05 1.0E+00 2.2E-05 Slope - Mount Robson

Debris Flows Mt. Robson Fan 2 495.95 495.96 1.0E+00 5.5E-03 1.0E+00 2.8E-03 1.0E-02 1.5E-07 1.9E-01 <1.0E-7

Debris Flows Mt. Robson Channel 2 495.96 495.96 1.0E+00 5.5E-03 1.0E+00 1.1E-02 5.0E-02 2.9E-06 1.0E+00 2.9E-06

Debris Flows Mt. Robson Fan 2 495.96 496.21 1.0E+00 5.5E-03 1.0E+00 2.8E-03 1.0E-02 1.5E-07 1.9E-01 <1.0E-7

Debris Flows Mt. Robson Fan 3 496.21 496.22 1.0E+00 5.5E-03 1.0E+00 2.7E-02 5.0E-02 7.5E-06 8.8E-01 6.6E-06

Debris Flows Mt. Robson Channel 3 496.22 496.24 1.0E+00 5.5E-03 1.0E+00 1.3E-02 1.0E-02 7.3E-07 1.0E+00 7.3E-07

Debris Flows Mt. Robson Fan 3 496.24 496.43 1.0E+00 5.5E-03 1.0E+00 2.7E-02 5.0E-02 7.5E-06 8.8E-01 6.6E-06

Debris Flows Mt. Terry Fox Fan 496.43 496.54 1.0E+00 5.5E-03 1.0E+00 1.7E-02 5.0E-02 4.7E-06 7.8E-01 3.6E-06

Debris Flows Mt. Terry Fox Fan 496.54 496.56 1.0E+00 5.5E-03 1.0E+00 1.7E-02 5.0E-02 4.7E-06 7.8E-01 3.6E-06

Scour (Local) Unnamed Channel 496.56 496.56 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 1.0E+00 5.0E-07

Debris Flows Mt. Terry Fox Channel 496.56 496.56 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 8.1E-06 8.0E-01 6.4E-06 2

Page 7 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Mt. Terry Fox Fan 496.56 496.72 1.0E+00 5.5E-03 1.0E+00 1.7E-02 5.0E-02 4.7E-06 7.8E-01 3.6E-06

Debris Slides Mt. Terry Fox - Mt. 497.03 498.54 1.0E+00 1.0E+00 1.0E-02 1.0E+00 1.0E-03 1.0E-05 1.0E+00 1.0E-05 Robson

Debris Flows Unnamed Channel 497.23 497.23 1.0E+00 1.7E-02 1.0E+00 1.2E-02 5.0E-02 1.0E-05 8.6E-01 9.0E-06

Scour (Local) Unnamed Channel 497.23 497.23 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Channel 497.63 497.65 1.0E+00 5.5E-03 1.0E+00 3.0E-02 5.0E-02 8.2E-06 1.0E+00 8.2E-06

Debris Flows Unnamed Channel 497.96 498.03 1.0E+00 1.7E-02 1.0E+00 6.5E-03 1.0E-02 1.1E-06 8.0E-01 9.0E-07

Scour (Local) Unnamed Channel 497.97 497.97 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-04 2.0E-07 1.0E+00 2.0E-07

Rock Avalanches Valemount Valley 505.37 505.72 1.0E+00 1.0E-05 1.0E-02 5.0E-01 1.0E+00 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Hogan Creek Fan 509.62 509.82 1.0E+00 5.5E-03 1.0E+00 3.9E-02 5.0E-03 1.1E-06 3.8E-01 4.0E-07

Scour (Local) Hogan Creek 509.82 509.83 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Hogan Creek 509.82 509.83 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 2.3E-02 <1.0E-7

Debris Floods Hogan Creek Fan 509.83 509.94 1.0E+00 5.5E-03 1.0E+00 3.9E-02 5.0E-03 1.1E-06 3.8E-01 4.0E-07

Debris Floods Teepee Creek 3 Fan 510.85 511.01 1.0E+00 5.5E-03 1.0E+00 8.6E-02 5.0E-03 2.3E-06 6.0E-01 1.4E-06

Scour (Local) Teepee Creek 511.01 511.01 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Teepee Creek 3 511.01 511.01 1.0E+00 1.7E-02 1.0E+00 1.0E-01 5.0E-03 8.7E-06 3.3E-01 2.8E-06

Debris Floods Teepee Creek 3 Fan 511.01 511.42 1.0E+00 5.5E-03 1.0E+00 8.6E-02 5.0E-03 2.3E-06 6.0E-01 1.4E-06

Debris Floods Teepee Creek 3 511.42 511.43 1.0E+00 5.5E-03 1.0E+00 6.7E-02 5.0E-03 1.8E-06 1.0E+00 1.8E-06 Channel 1

Debris Floods Teepee Creek 3 Fan 511.43 512.02 1.0E+00 5.5E-03 1.0E+00 8.6E-02 5.0E-03 2.3E-06 6.0E-01 1.4E-06

Avulsion Crooked Creek 513.06 513.44 1.0E+00 4.0E-05 1.0E+00 2.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Crooked Creek 513.06 513.44 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Crooked Creek 513.06 513.44 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Crooked Creek Fan 513.06 513.09 1.0E+00 5.5E-03 1.0E+00 9.1E-02 5.0E-03 2.5E-06 3.6E-01 9.0E-07

Debris Floods Crooked Creek 513.09 513.09 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.2E-01 <1.0E-7 Channel 3

Debris Floods Crooked Creek Fan 513.09 513.19 1.0E+00 5.5E-03 1.0E+00 9.1E-02 5.0E-03 2.5E-06 3.6E-01 9.0E-07

Debris Floods Crooked Creek 513.19 513.21 1.0E+00 5.5E-03 1.0E+00 1.8E-02 5.0E-03 4.8E-07 3.1E-01 1.5E-07 Channel 2

Debris Floods Crooked Creek Fan 513.21 513.25 1.0E+00 5.5E-03 1.0E+00 9.1E-02 5.0E-03 2.5E-06 3.6E-01 9.0E-07

Debris Floods Crooked Creek 513.25 513.28 1.0E+00 5.5E-03 1.0E+00 2.0E-02 5.0E-03 5.5E-07 9.6E-01 5.3E-07 Channel 1

Debris Floods Crooked Creek Fan 513.28 513.4 1.0E+00 5.5E-03 1.0E+00 9.1E-02 5.0E-03 2.5E-06 3.6E-01 9.0E-07

Page 8 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Crooked Creek 513.4 513.42 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-03 8.7E-07 1.0E-02 <1.0E-7

Debris Floods Crooked Creek Fan 513.42 513.43 1.0E+00 5.5E-03 1.0E+00 9.1E-02 5.0E-03 2.5E-06 3.6E-01 9.0E-07

Lateral Erosion Swift Creek 518.13 518.17 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 4.0E-01 1.2E-05 (Bank Erosion)

Scour (Local) Swift Creek 518.13 518.17 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Avulsion Canoe River 526.78 526.89 1.0E+00 1.1E-02 1.0E+00 1.9E-03 6.0E-03 1.3E-07 1.0E+00 1.3E-07

Lateral Erosion Canoe River 526.78 526.89 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 2.4E-01 7.1E-06 (Bank Erosion)

Scour (Local) Canoe River 526.78 526.89 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Lateral Erosion Camp Creek 529.92 530.02 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 2.4E-01 7.1E-06 (Bank Erosion)

Scour (Local) Camp Creek 529.92 530.02 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Rock Avalanches Canoe Mountain 532.39 536.96 1.0E+00 5.0E-05 1.0E-01 5.0E-01 1.0E+00 2.6E-06 1.0E+00 2.6E-06 North Slope - Canoe River

Debris Slides North East Slopes - 533.24 533.85 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 Canoe River

Debris Floods Unnamed Fan 535.69 535.71 1.0E+00 5.5E-03 1.0E+00 4.9E-07 5.0E-03 <1.0E-7 1.0E-02 <1.0E-7

Debris Floods Unnamed Channel 535.71 535.72 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E+00 2.7E-07

Debris Floods Unnamed Fan 535.72 535.97 1.0E+00 5.5E-03 1.0E+00 4.9E-07 5.0E-03 <1.0E-7 1.0E-02 <1.0E-7

Debris Floods Unnamed Fan 536.07 536.1 1.0E+00 5.5E-03 1.0E+00 3.6E-04 5.0E-03 <1.0E-7 1.5E-02 <1.0E-7

Scour (Local) Unnamed Channel 536.1 536.11 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Channel 536.1 536.11 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 2.5E-01 <1.0E-7

Debris Floods Unnamed Fan 536.11 536.11 1.0E+00 5.5E-03 1.0E+00 3.6E-04 5.0E-03 <1.0E-7 1.5E-02 <1.0E-7

Rockfall Canoe Mountain - 536.85 537.05 1.0E+00 1.0E-02 1.0E-02 5.0E-01 1.0E+00 5.0E-05 5.0E-02 2.5E-06 Albreda

Rock Avalanches Canoe Mountain 536.96 538.98 1.0E+00 2.0E-05 1.0E-01 5.0E-01 1.0E+00 1.1E-06 1.0E+00 1.1E-06 South Slope - Canoe River

Scour (Local) Unnamed Channel 537.44 537.44 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 537.44 537.44 1.0E+00 5.5E-03 1.0E+00 3.3E-02 5.0E-03 8.9E-07 2.1E-01 1.9E-07

Debris Floods Canoe Mountain Fan 538.34 538.75 1.0E+00 1.7E-02 1.0E+00 3.8E-02 1.0E-04 <1.0E-7 6.2E-01 <1.0E-7

Outburst Floods Columbia Mountains - 538.55 540.55 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Camp Creek Tributary 8 - Poem Peak West slope

Page 9 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Canoe Mountain 538.75 538.76 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7 Channel

Debris Floods Canoe Mountain Fan 538.76 539 1.0E+00 1.7E-02 1.0E+00 3.8E-02 1.0E-04 <1.0E-7 6.2E-01 <1.0E-7

Rock Avalanches Poem Peak - Albreda 538.98 542.54 1.0E+00 4.0E-05 1.0E-01 5.0E-01 1.0E+00 2.0E-06 1.0E+00 2.0E-06 River

Debris Flows Unnamed Channel Fan 539.18 539.23 1.0E+00 5.5E-03 1.0E+00 5.5E-03 1.0E-02 3.0E-07 3.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1 539.23 539.24 1.0E+00 1.7E-02 1.0E+00 2.0E-02 1.0E-02 3.5E-06 1.0E+00 3.5E-06

Debris Flows Unnamed Channel Fan 539.24 539.34 1.0E+00 5.5E-03 1.0E+00 5.5E-03 1.0E-02 3.0E-07 3.0E-01 <1.0E-7

Debris Flows Unnamed Channel 2 539.34 539.35 1.0E+00 5.5E-03 1.0E+00 1.2E-02 5.0E-02 3.3E-06 1.0E+00 3.3E-06

Debris Flows Unnamed Channel Fan 539.36 539.43 1.0E+00 5.5E-03 1.0E+00 5.5E-03 1.0E-02 3.0E-07 3.0E-01 <1.0E-7

Debris Flows Alberta Fan 539.73 539.75 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 6.2E-01 1.9E-06

Avulsion Unnamed Channel 539.75 540.84 1.0E+00 2.0E-05 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 539.75 540.84 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Unnamed Channel 539.75 540.84 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Debris Flows Alberta Fan 539.75 540.09 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 3.5E-01 1.1E-06

Debris Floods Mount Thompson Fan 540.09 540.09 1.0E+00 1.7E-02 1.0E+00 7.8E-02 1.0E-04 1.3E-07 4.2E-01 <1.0E-7

Debris Flows Alberta Fan 540.09 540.29 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 3.5E-01 1.1E-06

Debris Flows Alberta Fan Channel 540.29 540.3 1.0E+00 5.5E-02 1.0E+00 1.8E-02 2.0E-03 2.0E-06 4.0E-01 7.9E-07

Debris Flows Alberta Fan 540.3 540.32 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 3.5E-01 1.1E-06

Debris Flows Alberta Fan 540.32 540.33 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 3.5E-01 1.1E-06

Debris Flows Alberta Fan 540.33 540.84 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 3.5E-01 1.1E-06

Debris Flows Alberta Fan 540.84 541.25 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.1E-06 1.0E+00 3.1E-06

Scour (Local) Camp Creek 541.36 541.46 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Camp Creek 541.36 541.46 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-05 1.0E-07 8.0E-01 <1.0E-7 (Bank Erosion)

Debris Floods Camp Creek Fan 542.46 542.47 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 2.6E-01 1.6E-07

Scour (Local) Unnamed Channel 542.46 542.46 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Camp Creek Fan 542.47 542.84 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 2.6E-01 1.6E-07

Rock Avalanches Mount Milton North 542.54 547.51 1.0E+00 6.0E-05 1.0E-01 5.0E-01 1.0E+00 2.8E-06 1.0E+00 2.8E-06 Slope - Albreda River

Avulsion Camp Creek 542.84 543.46 1.0E+00 1.5E-02 1.0E+00 2.0E-03 1.0E-04 <1.0E-7 8.0E-01 <1.0E-7

Page 10 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Lateral Erosion Camp Creek 542.84 543.46 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Scour (Local) Camp Creek 542.84 543.46 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-04 2.0E-07 8.0E-01 1.6E-07

Debris Floods Camp Creek Fan 542.84 542.9 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 5.1E-02 <1.0E-7

Debris Floods Camp Creek Channel 1 542.9 542.9 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E-02 <1.0E-7

Debris Floods Camp Creek Fan 542.9 543.07 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 5.1E-02 <1.0E-7

Outburst Floods Columbia Mountains - 543.06 543.26 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Camp Creek and headwaters

Debris Floods Camp Creek Channel 2 543.07 543.07 1.0E+00 5.5E-03 1.0E+00 3.3E-02 5.0E-03 8.9E-07 1.9E-01 1.7E-07

Debris Floods Camp Creek Fan 543.07 543.12 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 5.1E-02 <1.0E-7

Debris Floods Camp Creek 3 543.12 543.14 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-03 8.7E-07 4.2E-02 <1.0E-7

Debris Floods Camp Creek Fan 543.14 543.28 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 5.1E-02 <1.0E-7

Debris Floods Camp Creek Channel 3 543.28 543.28 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E-02 <1.0E-7

Debris Floods Camp Creek Fan 543.28 543.45 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 5.1E-02 <1.0E-7

Debris Floods Camp Creek Channel 4 543.45 543.45 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 9.6E-01 2.6E-07

Debris Floods Camp Creek Fan 543.45 543.46 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 5.1E-02 <1.0E-7

Debris Floods Camp Creek Fan 543.46 543.71 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 2.6E-01 1.6E-07

Debris Floods Camp Creek Channel 5 543.71 543.71 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E+00 2.7E-07

Debris Floods Camp Creek Fan 543.71 543.75 1.0E+00 5.5E-03 1.0E+00 2.2E-02 5.0E-03 6.0E-07 2.6E-01 1.6E-07

Debris Flows Alberta Lake Fan 1 543.99 544.29 1.0E+00 1.7E-03 1.0E+00 4.1E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Alberta Lake Fan 2 544.57 544.98 1.0E+00 1.7E-03 1.0E+00 8.0E-03 5.0E-02 6.9E-07 1.0E+00 6.9E-07

Debris Floods Unnamed Fan 545.76 546.2 1.0E+00 1.7E-02 1.0E+00 3.6E-02 1.0E-04 <1.0E-7 6.1E-01 <1.0E-7

Scour (Local) Unnamed Channel 546.2 546.21 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Fan 546.21 546.22 1.0E+00 1.7E-02 1.0E+00 3.6E-02 1.0E-04 <1.0E-7 6.1E-01 <1.0E-7

Debris Floods Unnamed Fan 546.22 546.25 1.0E+00 1.7E-02 1.0E+00 3.6E-02 1.0E-04 <1.0E-7 6.1E-01 <1.0E-7

Debris Floods Deadfall Creek 546.25 546.25 1.0E+00 1.7E-02 1.0E+00 2.3E-01 1.0E-04 3.9E-07 1.0E+00 3.9E-07 Channel 1

Debris Floods Deadfall Creek Fan 546.25 546.25 1.0E+00 5.5E-02 1.0E+00 2.8E-02 1.0E-04 1.5E-07 5.7E-01 <1.0E-7

Debris Floods Deadfall Creek Fan 546.25 546.61 1.0E+00 5.5E-02 1.0E+00 2.8E-02 1.0E-04 1.5E-07 5.7E-01 <1.0E-7

Page 11 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Deadfall Creek 546.61 546.63 1.0E+00 1.7E-02 1.0E+00 1.4E-01 1.0E-04 2.4E-07 1.0E+00 2.4E-07 Channel 2

Scour (Local) Deadfall Creek 546.63 547.54 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Deadfall Creek Fan 546.63 547.07 1.0E+00 5.5E-02 1.0E+00 2.8E-02 1.0E-04 1.5E-07 3.3E-01 <1.0E-7

Debris Floods Deadfall Creek 547.07 547.08 1.0E+00 5.5E-02 1.0E+00 1.8E-01 1.0E-04 9.8E-07 6.7E-01 6.5E-07

Debris Floods Deadfall Creek Fan 547.08 547.54 1.0E+00 5.5E-02 1.0E+00 2.8E-02 1.0E-04 1.5E-07 3.3E-01 <1.0E-7

Rock Avalanches Mount Milton South 547.51 550.27 1.0E+00 3.0E-05 1.0E-01 5.0E-01 1.0E+00 1.5E-06 1.0E+00 1.5E-06 Slope - Albreda River

Debris Floods Unnamed Fan 547.63 547.82 1.0E+00 1.7E-03 1.0E+00 6.8E-02 5.0E-03 5.9E-07 5.3E-01 3.1E-07

Debris Floods Unnamed Channel 547.82 547.82 1.0E+00 1.7E-03 1.0E+00 1.9E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 547.82 547.96 1.0E+00 1.7E-03 1.0E+00 6.8E-02 5.0E-03 5.9E-07 5.3E-01 3.1E-07

Avulsion Albreda River 547.99 548.05 1.0E+00 2.3E-03 1.0E+00 1.9E-03 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Albreda River 547.99 548.05 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 4.0E-01 1.2E-05 (Bank Erosion)

Scour (Local) Albreda River 547.99 548.05 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Scour (Local) Robina Creek 548.07 548.83 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Robina Creek Fan 548.25 548.56 1.0E+00 5.5E-03 1.0E+00 9.2E-02 5.0E-03 2.5E-06 6.3E-01 1.6E-06

Debris Floods Robina Creek 548.56 548.58 1.0E+00 1.7E-02 1.0E+00 2.3E-01 2.5E-02 1.0E-04 4.3E-02 4.3E-06

Debris Floods Robina Creek Fan 548.58 548.83 1.0E+00 5.5E-03 1.0E+00 9.2E-02 5.0E-03 2.5E-06 3.6E-01 9.2E-07

Debris Flows Unnamed Creek Fan 550.54 550.56 1.0E+00 5.5E-03 1.0E+00 6.9E-03 1.0E-02 3.8E-07 1.0E+00 3.8E-07

Debris Flows Unnamed Creek 550.56 550.56 1.0E+00 5.5E-03 1.0E+00 2.9E-02 2.5E-02 4.0E-06 1.0E+00 4.0E-06 Channel 1

Debris Flows Unnamed Creek Fan 550.56 550.6 1.0E+00 5.5E-03 1.0E+00 6.9E-03 1.0E-02 3.8E-07 1.0E+00 3.8E-07

Debris Flows Unnamed Creek 550.6 550.6 1.0E+00 5.5E-03 1.0E+00 1.3E-02 2.5E-02 1.8E-06 1.0E+00 1.8E-06 Channel 2

Debris Flows Unnamed Creek Fan 550.6 550.68 1.0E+00 5.5E-03 1.0E+00 6.9E-03 1.0E-02 3.8E-07 1.0E+00 3.8E-07

Debris Flows Unnamed Creek 550.68 550.7 1.0E+00 5.5E-03 1.0E+00 9.6E-03 5.0E-02 2.6E-06 1.0E+00 2.6E-06 Channel 3

Debris Flows Unnamed Creek Fan 550.7 550.72 1.0E+00 5.5E-03 1.0E+00 6.9E-03 1.0E-02 3.8E-07 1.0E+00 3.8E-07

Debris Flows Unnamed Creek Fan 551.01 551.17 1.0E+00 5.5E-03 1.0E+00 1.3E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 551.17 551.17 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Creek 551.17 551.17 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 7.3E-02 <1.0E-7 Channel 1

Debris Flows Unnamed Creek Fan 551.17 551.29 1.0E+00 5.5E-03 1.0E+00 1.3E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Page 12 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Unnamed Fan 551.8 551.86 1.0E+00 5.5E-03 1.0E+00 2.9E-02 2.5E-02 4.0E-06 5.7E-01 2.3E-06

Scour (Local) Unnamed Channel 551.86 551.9 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Channel 551.86 551.87 1.0E+00 5.5E-03 1.0E+00 1.5E-01 2.5E-02 2.0E-05 3.5E-01 7.2E-06

Lateral Erosion Unnamed Channel 551.86 551.9 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Debris Floods Unnamed Fan 551.87 551.9 1.0E+00 5.5E-03 1.0E+00 2.9E-02 2.5E-02 4.0E-06 3.3E-01 1.3E-06

Debris Floods Unnamed Fan 552.31 552.34 1.0E+00 1.7E-03 1.0E+00 1.1E-03 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Clemina Fan 554.03 554.93 1.0E+00 5.5E-02 1.0E+00 7.2E-02 5.0E-03 2.0E-05 2.7E-01 5.3E-06

Lateral Erosion Clemina Creek 554.93 554.96 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Scour (Local) Clemina Creek 554.93 554.96 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-04 2.0E-07 8.0E-01 1.6E-07

Debris Floods Clemina Creek 554.93 554.96 1.0E+00 5.5E-02 1.0E+00 1.0E-02 5.0E-03 2.7E-06 1.0E-02 <1.0E-7

Debris Floods Clemina Fan 554.96 554.98 1.0E+00 5.5E-02 1.0E+00 7.2E-02 5.0E-03 2.0E-05 2.7E-01 5.3E-06

Debris Floods Dora Creek Fan 554.98 555.32 1.0E+00 1.7E-02 1.0E+00 5.5E-02 5.0E-03 4.7E-06 4.6E-01 2.2E-06

Lateral Erosion Dora Creek 555.32 555.37 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Dora Creek 555.32 555.37 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Dora Creek 555.32 555.37 1.0E+00 5.5E-02 1.0E+00 9.3E-02 5.0E-03 2.5E-05 1.1E-01 2.9E-06

Debris Floods Dora Creek Fan 555.37 555.6 1.0E+00 1.7E-02 1.0E+00 5.5E-02 5.0E-03 4.7E-06 4.6E-01 2.2E-06

Debris Floods Dora Creek Channel 1 555.6 555.64 1.0E+00 1.7E-02 1.0E+00 6.2E-02 5.0E-03 5.4E-06 1.0E+00 5.4E-06

Debris Floods Dora Creek Fan 555.64 556.11 1.0E+00 1.7E-02 1.0E+00 5.5E-02 5.0E-03 4.7E-06 4.6E-01 2.2E-06

Scour (Flooding) Albreda River 556.11 556.41 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Albreda River 556.65 556.74 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Albreda River 557.46 557.5 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 2.4E-01 7.1E-06 (Bank Erosion)

Scour (Local) Albreda River 557.46 557.5 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Avulsion Albreda River 557.46 557.5 1.0E+00 2.3E-04 1.0E+00 1.9E-03 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Albreda River 557.49 557.59 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Unnamed Fan 558.06 559.29 1.0E+00 5.5E-03 1.0E+00 2.0E-02 2.5E-02 2.8E-06 1.0E+00 2.8E-06

Rock Avalanches Mount Albreda 558.08 563.31 1.0E+00 6.0E-05 1.0E-01 5.0E-01 1.0E+00 2.9E-06 1.0E+00 2.9E-06

Scour (Local) Unnamed Channel 559.56 559.57 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Albreda River 559.66 559.69 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Page 13 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Albreda River 559.66 559.69 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Fan 560.9 561.28 1.0E+00 1.7E-03 1.0E+00 1.7E-04 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 561.41 561.42 1.0E+00 1.7E-03 1.0E+00 1.7E-04 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 561.42 561.44 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 561.44 561.53 1.0E+00 1.7E-03 1.0E+00 1.7E-04 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Unnamed Channel 561.62 562.19 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Unnamed Fan 561.63 561.95 1.0E+00 5.5E-03 1.0E+00 2.5E-03 5.0E-03 <1.0E-7 5.9E-02 <1.0E-7

Scour (Local) Unnamed Channel 561.95 561.95 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Fan 561.95 561.95 1.0E+00 5.5E-03 1.0E+00 2.5E-03 5.0E-03 <1.0E-7 1.0E-02 <1.0E-7

Debris Floods Unnamed Fan 561.95 562.06 1.0E+00 5.5E-03 1.0E+00 2.5E-03 5.0E-03 <1.0E-7 5.9E-02 <1.0E-7

Debris Floods Unnamed Channel 562.06 562.07 1.0E+00 5.5E-03 1.0E+00 8.5E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 562.07 562.19 1.0E+00 5.5E-03 1.0E+00 2.5E-03 5.0E-03 <1.0E-7 5.9E-02 <1.0E-7

Debris Floods Dominion Creek Fan 563.65 563.66 1.0E+00 1.7E-02 1.0E+00 9.1E-02 5.0E-03 7.9E-06 6.2E-01 4.9E-06

Avulsion Dominion Creek 563.66 563.71 1.0E+00 2.3E-03 1.0E+00 1.9E-03 2.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Dominion Creek 563.66 563.71 1.0E+00 4.9E-03 1.0E+00 1.0E+00 2.0E-02 9.8E-05 4.0E-01 3.9E-05 (Bank Erosion)

Scour (Local) Dominion Creek 563.66 563.71 1.0E+00 1.9E-03 1.0E+00 1.0E+00 2.0E-02 3.8E-05 8.0E-01 3.0E-05

Debris Floods Dominion Creek 563.66 563.71 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E-02 <1.0E-7

Debris Floods Dominion Creek Fan 563.71 563.84 1.0E+00 1.7E-02 1.0E+00 9.1E-02 5.0E-03 7.9E-06 6.2E-01 4.9E-06

Earth Landslide Dominion Creek - 563.84 564.28 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 South Slope

Earth Landslide Moonbeam Creek 567.12 567.8 1.0E+00 1.0E-02 1.0E+00 1.0E+00 5.0E-01 5.0E-03 1.0E-03 5.0E-06 North Slope - Lempriere

Rock Avalanches Mount Lempriere 567.8 570.4 1.0E+00 3.0E-05 1.0E-01 5.0E-01 1.0E+00 1.5E-06 1.0E+00 1.5E-06 North Slope - Lempriere

Lateral Erosion Moonbeam Creek 567.96 568 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Moonbeam Creek 567.96 568 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Moonbeam Creek 567.96 568 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 9.0E-01 2.5E-07

Debris Flows Lempira Fan 568.77 568.85 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.1E-06 1.0E+00 5.1E-06

Debris Flows Lempira Channel 1 568.85 568.86 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Lempira Fan 568.92 568.95 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.1E-06 1.0E+00 5.1E-06

Page 14 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Lempira Channel 2 568.95 568.96 1.0E+00 1.7E-02 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Lempira Fan 568.96 569.15 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.1E-06 1.0E+00 5.1E-06

Debris Flows Lempira Fan 569.28 569.32 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.1E-06 1.0E+00 5.1E-06

Debris Flows Lempira 2 Fan 569.41 569.41 1.0E+00 5.5E-03 1.0E+00 5.5E-03 5.0E-02 1.5E-06 1.0E+00 1.5E-06

Debris Flows Lempira 2 Channel 569.41 569.43 1.0E+00 5.5E-03 1.0E+00 4.1E-03 5.0E-02 1.1E-06 1.0E+00 1.1E-06

Debris Flows Lempira 2 Fan 569.43 569.43 1.0E+00 5.5E-03 1.0E+00 5.5E-03 5.0E-02 1.5E-06 1.0E+00 1.5E-06

Debris Flows Lempira 2 Fan 569.52 569.53 1.0E+00 5.5E-03 1.0E+00 5.5E-03 5.0E-02 1.5E-06 5.7E-01 8.5E-07

Scour (Local) Unnamed Channel 569.53 569.53 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Lempira 2 Fan 569.53 569.54 1.0E+00 5.5E-03 1.0E+00 5.5E-03 5.0E-02 1.5E-06 5.7E-01 8.5E-07

Debris Floods Unnamed Channel 569.54 569.55 1.0E+00 5.5E-03 1.0E+00 3.3E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Lempira 2 Fan 569.55 569.85 1.0E+00 5.5E-03 1.0E+00 5.5E-03 5.0E-02 1.5E-06 5.7E-01 8.5E-07

Rock Avalanches Mount Lempriere 570.4 572.27 1.0E+00 2.0E-05 5.0E-01 5.0E-01 1.0E+00 5.3E-06 1.0E+00 5.3E-06 Centre Slope - Lempriere

Debris Slides Mt. Lempriere Slope 570.6 572.27 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-03 1.0E-06 1.0E+00 1.0E-06 Toe

Debris Flows Lempira 3 Channel 570.64 570.65 1.0E+00 1.7E-02 1.0E+00 2.8E-02 5.0E-02 2.4E-05 4.0E-01 9.6E-06

Debris Flows Lempira 4 Channel 570.81 570.82 1.0E+00 5.5E-03 1.0E+00 4.3E-03 5.0E-02 1.2E-06 1.0E+00 1.2E-06

Debris Flows Lempira 5 Channel 571.02 571.02 1.0E+00 5.5E-03 1.0E+00 3.0E-02 5.0E-02 8.1E-06 1.0E+00 8.1E-06

Debris Flows Lempira 6 Channel 571.35 571.35 1.0E+00 5.5E-03 1.0E+00 1.7E-02 5.0E-02 4.7E-06 1.0E+00 4.7E-06

Debris Flows Lempira 7 Channel 571.73 571.73 1.0E+00 1.7E-02 1.0E+00 9.7E-03 5.0E-02 8.4E-06 1.0E+00 8.4E-06

Debris Flows Lempira 8 Channel 571.76 571.76 1.0E+00 1.7E-02 1.0E+00 6.5E-03 1.0E-02 1.1E-06 1.0E+00 1.1E-06

Debris Flows Lempira 9 Channel 571.93 571.93 1.0E+00 5.5E-03 1.0E+00 6.5E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Lempira 10 Channel 572.01 572.01 1.0E+00 5.5E-03 1.0E+00 7.5E-03 5.0E-02 2.0E-06 1.0E+00 2.0E-06

Rock Avalanches Mount Lempriere 572.27 573.95 1.0E+00 2.0E-05 5.0E-01 5.0E-01 1.0E+00 4.8E-06 1.0E+00 4.8E-06 South Slope - Lempriere

Debris Flows Unnamed Fan 572.31 572.34 1.0E+00 5.5E-03 1.0E+00 6.5E-03 1.0E-02 3.6E-07 3.4E-01 1.2E-07

Scour (Local) Unnamed Channel 572.34 572.34 1.0E+00 2.0E-03 1.0E+00 1.0E+00 5.0E-05 1.0E-07 8.0E-01 <1.0E-7

Debris Flows Unnamed Channel 572.34 572.34 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 4.7E-01 <1.0E-7

Debris Flows Unnamed Fan 572.34 572.67 1.0E+00 5.5E-03 1.0E+00 6.5E-03 1.0E-02 3.6E-07 3.4E-01 1.2E-07

Debris Flows Unnamed Channel 573.06 573.07 1.0E+00 1.7E-02 1.0E+00 6.4E-03 5.0E-02 5.6E-06 1.0E+00 5.6E-06

Debris Flows Switch Creek Fan 573.61 573.67 1.0E+00 5.5E-03 1.0E+00 1.3E-02 1.0E-02 7.2E-07 5.2E-01 3.7E-07

Page 15 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Switch Creek 573.67 573.67 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Switch Creek Channel 1 573.67 573.67 1.0E+00 1.7E-02 1.0E+00 4.5E-02 1.0E-02 7.8E-06 6.4E-01 5.0E-06

Debris Flows Switch Creek Fan 573.67 573.76 1.0E+00 5.5E-03 1.0E+00 1.3E-02 1.0E-02 7.2E-07 5.2E-01 3.7E-07

Debris Flows Switch Creek Channel 2 573.76 573.77 1.0E+00 5.5E-03 1.0E+00 7.3E-03 5.0E-02 2.0E-06 1.0E+00 2.0E-06

Debris Flows Switch Creek Fan 573.77 573.85 1.0E+00 5.5E-03 1.0E+00 1.3E-02 1.0E-02 7.2E-07 5.2E-01 3.7E-07

Scour (Local) Unnamed Channel 574.69 574.69 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Earth Landslide Serpentine Creek 574.86 576.25 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 North Slopes

Debris Flows Switch Back Channel 1 575.99 576 1.0E+00 5.5E-03 1.0E+00 2.0E-02 5.0E-02 5.5E-06 1.0E+00 5.5E-06

Debris Flows Switch Back Channel 2 576.02 576.03 1.0E+00 1.7E-03 1.0E+00 4.5E-02 5.0E-02 3.9E-06 1.0E+00 3.9E-06

Debris Floods Serpentine Creek Fan 576.27 576.35 1.0E+00 1.7E-02 1.0E+00 3.1E-02 2.5E-02 1.4E-05 5.9E-01 8.0E-06

Lateral Erosion Serpentine Creek 576.35 576.39 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Serpentine Creek 576.35 576.39 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Serpentine Creek 576.35 576.39 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-03 8.7E-07 1.0E-02 <1.0E-7

Debris Floods Serpentine Creek Fan 576.39 576.66 1.0E+00 1.7E-02 1.0E+00 3.1E-02 2.5E-02 1.4E-05 5.9E-01 8.0E-06

Debris Floods Serpentine Creek Fan 576.66 576.77 1.0E+00 5.5E-03 1.0E+00 3.1E-02 2.5E-02 4.3E-06 5.9E-01 2.5E-06

Lateral Erosion North Thompson River 576.95 577.28 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-02 4.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) North Thompson River 576.95 577.28 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-02 2.0E-05 1.0E-03 <1.0E-7

Avulsion North Thompson River 576.95 577.28 1.0E+00 3.0E-02 1.0E+00 1.0E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) North Thompson River 577.07 577.17 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Chappell Creek Fan 577.28 578.02 1.0E+00 5.5E-03 1.0E+00 1.9E-02 2.5E-02 2.6E-06 6.2E-01 1.6E-06

Lateral Erosion Chappell Creek 578.02 578.04 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Scour (Local) Chappell Creek 578.02 578.04 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 8.0E-01 4.0E-07

Debris Floods Chappell Creek 578.02 578.04 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E-02 <1.0E-7

Debris Floods Chappell Creek Fan 578.04 578.69 1.0E+00 5.5E-03 1.0E+00 1.9E-02 2.5E-02 2.6E-06 1.0E+00 2.6E-06

Debris Floods Unnamed Channel 578.69 578.69 1.0E+00 1.7E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 578.69 578.77 1.0E+00 1.7E-03 1.0E+00 5.2E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Page 16 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Avalanches Mount Cheadle West 578.73 581.78 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 8.6E-06 1.0E+00 8.6E-06 Valley Slope 1 - Thunder River

Debris Flows Unnamed Channel 578.77 578.77 1.0E+00 1.7E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 578.77 578.83 1.0E+00 1.7E-03 1.0E+00 5.2E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Slides Chappell Creek South 578.8 580.3 1.0E+00 1.0E-03 1.0E-03 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 West Slopes

Debris Flows Amy Creek Fan 578.92 578.98 1.0E+00 1.7E-03 1.0E+00 4.6E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Amy Creek Channel 1 578.98 578.98 1.0E+00 1.7E-03 1.0E+00 8.3E-03 2.5E-02 3.6E-07 1.0E+00 3.6E-07

Debris Flows Amy Creek Fan 578.98 579.02 1.0E+00 1.7E-03 1.0E+00 4.6E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Amy Creek Channel 2 579.02 579.04 1.0E+00 1.7E-03 1.0E+00 2.8E-02 2.5E-02 1.2E-06 1.0E+00 1.2E-06

Debris Flows Amy Creek Fan 579.04 579.1 1.0E+00 1.7E-03 1.0E+00 4.6E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Amy Creek Channel 3 579.1 579.1 1.0E+00 1.7E-03 1.0E+00 1.9E-02 5.0E-02 1.6E-06 1.0E+00 1.6E-06

Debris Flows Amy Creek Fan 579.1 579.15 1.0E+00 1.7E-03 1.0E+00 4.6E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Amy Creek Channel 4 579.15 579.15 1.0E+00 1.7E-03 1.0E+00 2.0E-02 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Amy Creek Fan 579.15 579.24 1.0E+00 1.7E-03 1.0E+00 4.6E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Amy Creek Channel 5 579.24 579.24 1.0E+00 1.7E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Amy Creek Fan 579.24 579.3 1.0E+00 1.7E-03 1.0E+00 4.6E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Amy Creek 579.6 579.6 1.0E+00 1.7E-02 1.0E+00 2.0E-03 5.0E-03 1.7E-07 1.0E+00 1.7E-07

Debris Flows Unnamed Channel 579.92 579.92 1.0E+00 1.7E-02 1.0E+00 2.0E-02 5.0E-03 1.7E-06 1.0E+00 1.7E-06

Earth Landslide Mt. Cheadle West 580.32 583.66 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 Slope 1

Debris Flows Unnamed Channel 581.03 581.03 1.0E+00 1.7E-03 1.0E+00 0.0E+00 2.5E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 581.28 581.28 1.0E+00 1.7E-02 1.0E+00 2.0E-02 5.0E-03 1.7E-06 1.0E+00 1.7E-06

Debris Flows Unnamed Channel 581.59 581.59 1.0E+00 5.5E-03 1.0E+00 3.5E-02 2.5E-02 4.8E-06 1.0E+00 4.8E-06

Rock Avalanches Mount Cheadle West 581.78 586.5 1.0E+00 5.0E-05 5.0E-01 5.0E-01 1.0E+00 1.3E-05 1.0E+00 1.3E-05 Valley Slope 2 - Thunder River

Debris Flows Unnamed Channel 581.94 581.95 1.0E+00 5.5E-03 1.0E+00 1.6E-02 5.0E-02 4.3E-06 1.0E+00 4.3E-06

Debris Flows Unnamed Fan 581.95 582.02 1.0E+00 5.5E-03 1.0E+00 1.8E-02 5.0E-02 4.8E-06 1.0E+00 4.8E-06

Debris Flows Unnamed Channel 582.02 582.03 1.0E+00 5.5E-03 1.0E+00 2.4E-02 5.0E-02 6.7E-06 1.0E+00 6.7E-06

Debris Flows Unnamed Fan 582.03 582.05 1.0E+00 5.5E-03 1.0E+00 1.8E-02 5.0E-02 4.8E-06 1.0E+00 4.8E-06

Debris Flows Unnamed Channel 582.29 582.31 1.0E+00 1.7E-02 1.0E+00 1.3E-02 5.0E-02 1.2E-05 7.0E-01 8.1E-06

Page 17 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Fan 582.64 582.65 1.0E+00 5.5E-03 1.0E+00 9.7E-03 5.0E-02 2.6E-06 6.7E-01 1.8E-06

Debris Flows Unnamed Channel 582.65 582.66 1.0E+00 5.5E-03 1.0E+00 4.8E-02 2.5E-02 6.6E-06 1.0E+00 6.6E-06

Debris Flows Unnamed Fan 582.66 582.97 1.0E+00 5.5E-03 1.0E+00 9.7E-03 5.0E-02 2.6E-06 6.7E-01 1.8E-06

Debris Flows Unnamed Channel 582.97 582.97 1.0E+00 5.5E-03 1.0E+00 3.2E-02 5.0E-02 8.7E-06 1.0E+00 8.7E-06

Debris Flows Unnamed Fan 582.97 583.22 1.0E+00 5.5E-03 1.0E+00 9.7E-03 5.0E-02 2.6E-06 6.7E-01 1.8E-06

Debris Flows Unnamed Fan 583.67 584.31 1.0E+00 1.7E-02 1.0E+00 1.4E-02 5.0E-02 1.2E-05 5.3E-01 6.4E-06

Debris Flows Unnamed Channel 584.31 584.32 1.0E+00 1.7E-02 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 584.32 584.34 1.0E+00 1.7E-02 1.0E+00 1.4E-02 5.0E-02 1.2E-05 5.3E-01 6.4E-06

Debris Flows Unnamed Fan 584.34 584.41 1.0E+00 1.7E-02 1.0E+00 8.6E-03 1.0E-02 1.5E-06 4.0E-01 6.0E-07

Debris Flows Unnamed Channel 584.41 584.42 1.0E+00 1.7E-02 1.0E+00 2.3E-02 2.5E-02 1.0E-05 7.0E-01 7.2E-06

Debris Flows Unnamed Fan 584.42 584.5 1.0E+00 1.7E-02 1.0E+00 8.6E-03 1.0E-02 1.5E-06 4.0E-01 6.0E-07

Debris Flows Unnamed Channel 584.65 584.66 1.0E+00 1.7E-02 1.0E+00 5.8E-03 2.5E-02 2.5E-06 1.0E+00 2.5E-06

Debris Flows Unnamed Fan 585.25 585.37 1.0E+00 5.5E-03 1.0E+00 1.4E-04 1.0E-02 <1.0E-7 2.5E-02 <1.0E-7

Debris Flows Unnamed Channel 585.37 585.38 1.0E+00 1.7E-02 1.0E+00 2.0E-02 1.0E-02 3.5E-06 1.0E+00 3.5E-06

Debris Flows Unnamed Fan 585.38 585.45 1.0E+00 5.5E-03 1.0E+00 1.4E-04 1.0E-02 <1.0E-7 2.5E-02 <1.0E-7

Earth Landslide Mt. Cheadle West 585.46 585.92 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-03 1.0E-05 1.0E+00 1.0E-05 Slope 2

Debris Flows Unnamed Channel 585.49 585.49 1.0E+00 5.5E-03 1.0E+00 6.7E-03 5.0E-02 1.8E-06 1.0E+00 1.8E-06

Debris Slides North Thompson West 585.53 585.92 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-03 1.0E-07 1.0E+00 1.0E-07 Slope

Debris Flows Cermania Creek Fan 585.96 586.07 1.0E+00 1.7E-03 1.0E+00 1.5E-02 2.5E-02 6.3E-07 7.5E-01 4.8E-07

Debris Flows Cermania Creek 586.07 586.08 1.0E+00 1.7E-02 1.0E+00 3.5E-02 2.5E-02 1.5E-05 3.0E-01 4.5E-06

Debris Flows Cermania Creek Fan 586.08 586.12 1.0E+00 1.7E-03 1.0E+00 1.5E-02 2.5E-02 6.3E-07 7.5E-01 4.8E-07

Debris Flows Cermania Creek 586.12 586.13 1.0E+00 1.7E-02 1.0E+00 2.0E-02 5.0E-03 1.7E-06 1.0E+00 1.7E-06 Channel 1

Debris Flows Cermania Creek Fan 586.13 586.21 1.0E+00 1.7E-03 1.0E+00 1.5E-02 2.5E-02 6.3E-07 7.5E-01 4.8E-07

Debris Flows Cermania Creek 586.21 586.23 1.0E+00 1.7E-03 1.0E+00 1.2E-02 5.0E-03 1.1E-07 1.0E+00 1.1E-07 Channel 2

Debris Flows Cermania Creek Fan 586.23 586.3 1.0E+00 1.7E-03 1.0E+00 1.5E-02 2.5E-02 6.3E-07 7.5E-01 4.8E-07

Debris Flows Cermania Creek 586.3 586.31 1.0E+00 1.7E-02 1.0E+00 3.6E-02 2.5E-02 1.5E-05 5.4E-01 8.4E-06 Channel 3

Debris Flows Cermania Creek Fan 586.31 586.41 1.0E+00 1.7E-03 1.0E+00 1.5E-02 2.5E-02 6.3E-07 7.5E-01 4.8E-07

Page 18 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Avalanches Mount Cheadle West 586.49 589.46 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 8.4E-06 1.0E+00 8.4E-06 Valley Slope 3 - Thunder River

Debris Flows Unnamed Fan 586.55 586.61 1.0E+00 5.5E-03 1.0E+00 1.1E-02 1.0E-02 6.3E-07 1.0E+00 6.3E-07

Debris Flows Unnamed Fan 586.61 586.74 1.0E+00 5.5E-03 1.0E+00 1.1E-02 1.0E-02 6.3E-07 1.0E+00 6.3E-07

Debris Flows Unnamed Channel 586.61 586.61 1.0E+00 5.5E-03 1.0E+00 2.0E-02 5.0E-03 5.5E-07 1.0E+00 5.5E-07

Debris Flows Unnamed Channel 586.74 586.75 1.0E+00 5.5E-03 1.0E+00 6.5E-03 5.0E-03 1.8E-07 1.0E+00 1.8E-07

Debris Flows Unnamed Fan 586.75 586.82 1.0E+00 5.5E-03 1.0E+00 1.1E-02 1.0E-02 6.3E-07 1.0E+00 6.3E-07

Debris Flows Unnamed Channel 587.02 587.03 1.0E+00 1.7E-02 1.0E+00 3.4E-02 2.5E-02 1.5E-05 4.2E-01 6.2E-06

Debris Flows Unnamed Fan 587.13 587.23 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.3E-06 1.0E+00 5.3E-06

Debris Flows Unnamed Channel 587.23 587.25 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.8E-07 1.0E+00 2.8E-07

Debris Flows Unnamed Fan 587.25 587.58 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.3E-06 1.0E+00 5.3E-06

Scour (Flooding) Miledge Creek 588.2 589.14 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Outburst Floods Columbia Mountains - 588.54 589.44 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Miledge Creek and headwaters

Debris Floods Miledge Creek Fan 588.81 588.98 1.0E+00 1.7E-02 1.0E+00 1.0E-01 2.5E-02 4.5E-05 2.9E-01 1.3E-05

Avulsion Miledge Creek 588.98 589.02 1.0E+00 1.2E+00 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Miledge Creek 588.98 589.02 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Miledge Creek 588.98 589.02 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Slides Saint Anne Slope Toe - 589.47 590.82 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-03 1.0E-06 1.0E+00 1.0E-06 Thunder River

Rock Avalanches Saint Anne SE4 North 591.52 593.73 1.0E+00 2.0E-05 5.0E-01 5.0E-01 1.0E+00 6.2E-06 1.0E+00 6.2E-06 Slope - Thunder River

Scour (Local) Unnamed Channel 592.25 592.26 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 592.33 592.34 1.0E+00 5.5E-03 1.0E+00 4.8E-03 2.5E-02 6.5E-07 1.0E+00 6.5E-07

Scour (Local) Unnamed Channel 592.44 592.44 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Miguel Creek 592.44 592.44 1.0E+00 1.7E-02 1.0E+00 6.5E-03 2.0E-03 2.3E-07 3.4E-01 <1.0E-7

Debris Flows Unnamed Channel 592.56 592.56 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 1.0E+00 1.1E-07

Debris Floods Carlos Creek 592.63 592.64 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E+00 2.7E-07

Debris Floods Fernando Creek 592.84 592.84 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 593.2 593.21 1.0E+00 1.7E-02 1.0E+00 7.5E-02 2.5E-02 3.2E-05 2.3E-01 7.3E-06

Rock Avalanches Saint Anne SE4 South 593.73 595.92 1.0E+00 2.0E-05 1.0E-02 5.0E-01 1.0E+00 1.2E-07 1.0E+00 1.2E-07 Slope - Thunder River

Page 19 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Channel 594.26 594.27 1.0E+00 1.7E-02 1.0E+00 4.5E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Mount Saint Anne Fan 594.55 594.59 1.0E+00 5.5E-03 1.0E+00 2.9E-04 1.0E-02 <1.0E-7 4.0E-02 <1.0E-7

Debris Flows Mount Saint Anne 594.59 594.6 1.0E+00 5.5E-03 1.0E+00 2.0E-02 2.0E-03 2.2E-07 1.0E+00 2.2E-07 Channel 2

Debris Flows Mount Saint Anne 594.59 594.59 1.0E+00 5.5E-03 1.0E+00 2.3E-03 5.0E-02 6.3E-07 1.0E+00 6.3E-07 Channel 1

Debris Flows Mount Saint Anne Fan 594.59 594.59 1.0E+00 5.5E-03 1.0E+00 2.9E-04 1.0E-02 <1.0E-7 4.0E-02 <1.0E-7

Debris Flows Mount Saint Anne Fan 594.6 594.64 1.0E+00 5.5E-03 1.0E+00 2.9E-04 1.0E-02 <1.0E-7 4.0E-02 <1.0E-7

Earth Landslide Thunder Slide - 594.84 595.25 1.0E+00 1.0E-03 1.0E+00 1.0E+00 5.0E-01 5.0E-04 1.9E-02 9.6E-06 Thunder River

Outburst Floods Columbia Mountains - 596.04 596.54 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-02 1.0E-07 1.0E+00 1.0E-07 Thunder River and headwaters

Lateral Erosion Thunder River 596.29 596.33 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Thunder River 596.29 596.33 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Slides Mt. Cook 1 - Thunder 599.06 600.06 1.0E+00 1.0E+00 1.0E-03 1.0E+00 1.0E-03 1.0E-06 1.0E+00 1.0E-06 River

Debris Flows Unnamed Fan 599.1 599.31 1.0E+00 1.7E-02 1.0E+00 5.6E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 599.35 599.38 1.0E+00 1.7E-02 1.0E+00 2.1E-05 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 599.38 599.39 1.0E+00 1.7E-02 1.0E+00 1.6E-02 5.0E-02 1.4E-05 6.3E-01 8.7E-06

Debris Flows Unnamed Fan 599.39 599.44 1.0E+00 1.7E-02 1.0E+00 2.1E-05 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Earth Landslide Mt. Cook Toe Slopes 599.4 602.65 1.0E+00 1.0E-03 1.0E+00 1.0E+00 5.0E-01 5.0E-04 1.7E-02 8.4E-06 (578 Wrinkle) - Thunder River

Debris Flows Unnamed Channel 599.94 599.95 1.0E+00 5.5E-03 1.0E+00 3.7E-02 5.0E-02 1.0E-05 5.6E-01 5.7E-06

Debris Slides Mt. Cook 2 - Thunder 600.53 601.19 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 River

Rock Slide Mount Cook - Thunder 600.61 600.81 1.0E+00 1.6E-04 1.0E-02 1.0E-01 1.0E+00 1.6E-07 1.0E+00 1.6E-07 River

Debris Flows Whitewater Creek Fan 601.15 601.24 1.0E+00 1.7E-02 1.0E+00 2.0E-02 5.0E-02 1.7E-05 2.8E-01 4.9E-06

Outburst Floods Columbia Mountains - 601.19 601.39 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Whitewater Creek and headwaters

Avulsion Whitewater Creek 601.19 601.32 1.0E+00 1.5E-03 1.0E+00 2.0E-03 1.0E-04 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Whitewater Creek 601.19 601.32 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Debris Slides Whitewater Creek 601.19 601.38 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 North Slopes

Page 20 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Whitewater Creek 601.19 601.32 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 8.0E-01 1.5E-07

Debris Flows Whitewater Creek 601.24 601.26 1.0E+00 1.7E-02 1.0E+00 3.4E-02 5.0E-02 3.0E-05 1.5E-01 4.3E-06

Debris Flows Whitewater Creek Fan 601.26 601.39 1.0E+00 1.7E-02 1.0E+00 2.0E-02 5.0E-02 1.7E-05 2.8E-01 4.9E-06

Debris Slides Whitewater Creek 601.38 602.04 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 South Slopes

Scour (Local) Unnamed Channel 601.96 601.96 1.0E+00 2.0E-03 1.0E+00 1.0E+00 5.0E-05 1.0E-07 1.0E+00 1.0E-07

Scour (Local) Kalter creek 602.69 602.69 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Kalter Creek 602.69 602.7 1.0E+00 5.5E-03 1.0E+00 5.9E-02 5.0E-02 1.6E-05 5.9E-01 9.6E-06

Debris Slides Mt. Cook 3 - Thunder 602.74 603.48 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 River

Debris Floods Topp Creek Fan 603.53 603.63 1.0E+00 5.5E-03 1.0E+00 7.2E-02 5.0E-03 2.0E-06 5.4E-01 1.1E-06

Debris Floods Topp Creek 603.63 603.63 1.0E+00 5.5E-03 1.0E+00 3.3E-02 1.0E-04 <1.0E-7 3.0E-01 <1.0E-7

Debris Floods Topp Creek Fan 603.63 603.75 1.0E+00 5.5E-03 1.0E+00 7.2E-02 5.0E-03 2.0E-06 5.4E-01 1.1E-06

Scour (Local) Unnamed Channel 603.63 603.63 1.0E+00 2.0E-03 1.0E+00 1.0E+00 5.0E-05 1.0E-07 1.0E+00 1.0E-07

Scour (Flooding) North Thompson River 604.57 605.18 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Outburst Floods Columbia Mountains - 605.08 605.48 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Cook Creek and headwaters

Scour (Local) Cook Creek 605.47 605.5 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Cook Creek 605.47 605.5 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 9.0E-01 2.5E-07

Lateral Erosion Cook Creek 605.47 605.5 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) North Thompson River 605.48 609.79 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Cedar Creek 607.74 607.75 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Blue River 609.87 609.97 1.0E+00 2.0E-03 1.0E+00 1.0E+00 6.0E-03 1.2E-05 1.0E-03 <1.0E-7

Lateral Erosion Blue River 609.87 609.97 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Flooding) North Thompson River 615.92 616.11 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) North Thompson River 615.94 616.71 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-02 2.0E-05 1.0E-03 <1.0E-7

Avulsion North Thompson River 615.94 616.71 1.0E+00 4.5E-03 1.0E+00 1.0E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion North Thompson River 615.94 616.71 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-02 4.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Page 21 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Fan 618.1 618.28 1.0E+00 5.5E-03 1.0E+00 9.0E-03 5.0E-02 2.5E-06 1.0E+00 2.5E-06

Debris Flows Unnamed Channel 618.28 618.29 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 618.29 618.29 1.0E+00 5.5E-03 1.0E+00 9.0E-03 5.0E-02 2.5E-06 1.0E+00 2.5E-06

Debris Flows Unnamed Fan 619.97 620.06 1.0E+00 5.5E-03 1.0E+00 4.9E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Slides Ptarmigan Mountain 620.03 620.75 1.0E+00 1.0E+00 1.0E-03 1.0E+00 1.0E-03 1.0E-06 1.0E+00 1.0E-06 1 - Blue River

Debris Flows Unnamed Channel 620.06 620.06 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 620.06 620.16 1.0E+00 5.5E-03 1.0E+00 4.9E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Slides Ptarmigan Mountain 620.76 621.64 1.0E+00 1.0E-03 1.0E-03 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 2 - Blue River

Debris Floods Unnamed Channel 621.01 621.01 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Outburst Floods Shushwap - Froth 622.4 622.95 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 Creek and headwaters

Lateral Erosion Froth Creek 622.66 622.69 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Froth Creek 622.66 622.69 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Froth Creek 622.66 622.69 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.1E-01 <1.0E-7

Scour (Flooding) North Thompson River 624.02 624.62 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) North Thompson River 624.63 625.07 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Flows Unnamed Channel 624.68 624.69 1.0E+00 1.7E-02 1.0E+00 2.2E-03 5.0E-02 1.9E-06 1.0E+00 1.9E-06

Debris Flows Unnamed Fan 625.58 625.84 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 4.0E-06 1.0E+00 4.0E-06

Debris Flows Unnamed Channel 625.84 625.84 1.0E+00 5.5E-03 1.0E+00 2.3E-02 2.5E-02 3.1E-06 1.0E+00 3.1E-06

Debris Flows Unnamed Fan 625.84 625.94 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 4.0E-06 1.0E+00 4.0E-06

Debris Flows Unnamed Channel 626.1 626.1 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.5E-02 2.7E-07 1.0E+00 2.7E-07

Debris Flows Unnamed Fan 626.1 626.25 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 4.0E-06 1.0E+00 4.0E-06

Debris Flows Unnamed Fan 626.1 626.1 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 4.0E-06 1.0E+00 4.0E-06

Earth Landslide North Thompson East 626.5 626.84 1.0E+00 1.0E-01 1.0E-01 1.0E+00 1.0E-02 1.0E-04 1.6E-02 1.6E-06 Bank - Blue River

Rockfall Froth to Finn Creek 627.63 628.13 1.0E+00 1.0E+00 1.0E-04 1.0E-01 5.0E-01 5.0E-06 1.0E+00 5.0E-06 Cut Slope

Rock Slide Enfers Peak - Blue River 627.63 628.13 1.0E+00 3.9E-04 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 628.14 628.14 1.0E+00 1.7E-02 1.0E+00 2.5E-03 5.0E-02 2.1E-06 1.0E+00 2.1E-06

Debris Flows Unnamed Channel 628.32 628.32 1.0E+00 1.7E-03 1.0E+00 2.0E-03 5.0E-02 1.7E-07 1.0E+00 1.7E-07

Page 22 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Channel 628.63 628.64 1.0E+00 1.7E-03 1.0E+00 1.6E-02 2.5E-02 7.1E-07 1.0E+00 7.1E-07

Debris Floods Gamble Creek Fan 628.95 629.24 1.0E+00 1.7E-02 1.0E+00 6.5E-02 5.0E-03 5.6E-06 1.0E+00 5.6E-06

Scour (Local) Foam Creek/Gamble 629.24 629.27 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-04 2.5E-06 8.0E-01 2.0E-06 Creek

Lateral Erosion Foam Creek/Gamble 629.24 629.27 1.0E+00 4.9E-03 1.0E+00 1.0E+00 5.0E-04 2.4E-06 8.0E-01 2.0E-06 (Bank Erosion) Creek

Debris Floods Gamble Creek 629.24 629.27 1.0E+00 1.7E-02 1.0E+00 1.9E-01 1.0E-04 3.3E-07 8.3E-01 2.7E-07

Debris Floods Gamble Creek Fan 629.27 629.29 1.0E+00 1.7E-02 1.0E+00 6.5E-02 5.0E-03 5.6E-06 8.0E-01 4.5E-06

Earth Landslide Gamble Creek - Blue 629.29 629.34 1.0E+00 1.0E+00 1.0E-02 1.0E+00 1.0E-02 1.0E-04 8.0E-02 8.0E-06 River

Debris Floods Gamble Creek Fan 629.29 629.57 1.0E+00 1.7E-02 1.0E+00 6.5E-02 5.0E-03 5.6E-06 1.0E+00 5.6E-06

Debris Flows Unnamed Channel 632.09 632.09 1.0E+00 1.7E-03 1.0E+00 2.1E-02 5.0E-03 1.8E-07 1.0E+00 1.8E-07

Lateral Erosion Finn Creek 633.89 633.95 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 2.4E-01 7.1E-06 (Bank Erosion)

Scour (Local) Finn Creek 633.89 633.95 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Debris Flows Whiterock Creek Fan 637.02 637.37 1.0E+00 1.7E-02 1.0E+00 9.0E-03 5.0E-02 7.8E-06 1.0E+00 7.8E-06

Debris Flows Whiterock Creek 637.37 637.37 1.0E+00 1.7E-02 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Whiterock Creek Fan 637.37 637.44 1.0E+00 1.7E-02 1.0E+00 9.0E-03 5.0E-02 7.8E-06 1.0E+00 7.8E-06

Scour (Local) Unnamed Channel 637.37 637.37 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Greyrock Creek 637.44 637.47 1.0E+00 1.7E-02 1.0E+00 6.5E-03 5.0E-03 5.6E-07 1.0E+00 5.6E-07

Debris Flows Greyrock Creek Fan 637.47 637.65 1.0E+00 1.7E-02 1.0E+00 9.0E-03 5.0E-02 7.8E-06 1.0E+00 7.8E-06

Debris Flows Blackrock Creek 637.65 637.65 1.0E+00 1.7E-02 1.0E+00 5.8E-03 2.5E-02 2.5E-06 1.0E+00 2.5E-06

Debris Flows Blackrock Creek Fan 637.65 637.68 1.0E+00 1.7E-02 1.0E+00 9.0E-03 5.0E-02 7.8E-06 1.0E+00 7.8E-06

Debris Flows Blackrock Creek Fan 637.68 637.85 1.0E+00 1.7E-03 1.0E+00 1.2E-02 1.0E-02 2.0E-07 1.0E+00 2.0E-07

Debris Slides Groundhog Mountain 637.71 638.61 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 1 - Avola

Scour (Flooding) North Thompson River 637.85 639.08 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Slides Groundhog Mountain 638.61 639.19 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 2 - Avola

Rockfall Groundhog Mountain 639.08 639.19 1.0E+00 1.0E-01 1.0E-02 5.0E-01 1.0E+00 5.0E-04 3.0E-02 1.5E-05

Debris Slides Groundhog Mountain 639.34 640.24 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 3 - Avola

Debris Flows Unnamed Fan 639.39 639.4 1.0E+00 5.5E-03 1.0E+00 2.8E-02 5.0E-02 7.7E-06 1.0E+00 7.7E-06

Debris Flows Unnamed Channel 639.4 639.4 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 1.0E+00 1.1E-07

Page 23 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Fan 639.4 640.07 1.0E+00 5.5E-03 1.0E+00 2.8E-02 5.0E-02 7.7E-06 1.0E+00 7.7E-06

Debris Flows Unnamed Fan 640.07 640.09 1.0E+00 5.5E-03 1.0E+00 4.5E-03 5.0E-02 1.2E-06 1.0E+00 1.2E-06

Debris Flows Unnamed Fan 640.09 640.3 1.0E+00 5.5E-03 1.0E+00 4.5E-03 5.0E-02 1.2E-06 1.0E+00 1.2E-06

Debris Flows Unnamed Channel 640.09 640.09 1.0E+00 5.5E-03 1.0E+00 7.0E-04 5.0E-02 1.9E-07 1.0E+00 1.9E-07

Debris Flows Unnamed Fan 640.3 640.5 1.0E+00 1.7E-02 1.0E+00 6.6E-03 5.0E-02 5.7E-06 1.0E+00 5.7E-06

Scour (Local) Unnamed Channel 640.5 640.5 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 8.0E-01 2.0E-07

Debris Flows Unnamed Channel 640.5 640.5 1.0E+00 1.7E-02 1.0E+00 2.0E-03 1.0E-02 3.5E-07 5.0E-01 1.7E-07

Debris Flows Unnamed Fan 640.5 640.61 1.0E+00 1.7E-02 1.0E+00 6.6E-03 5.0E-02 5.7E-06 1.0E+00 5.7E-06

Debris Floods Unnamed Fan 640.72 640.89 1.0E+00 1.7E-02 1.0E+00 8.0E-02 5.0E-03 7.0E-06 5.8E-01 4.0E-06

Debris Floods Unnamed Channel 640.89 640.9 1.0E+00 1.7E-02 1.0E+00 3.3E-01 1.0E-04 5.8E-07 1.0E+00 5.8E-07

Debris Floods Unnamed Fan 640.9 641.07 1.0E+00 1.7E-02 1.0E+00 8.0E-02 5.0E-03 7.0E-06 5.8E-01 4.0E-06

Debris Flows Unnamed Fan 641.07 641.39 1.0E+00 5.5E-03 1.0E+00 4.8E-03 1.0E-02 2.6E-07 1.0E+00 2.6E-07

Debris Flows Unnamed Fan 641.39 641.59 1.0E+00 5.5E-03 1.0E+00 1.6E-02 1.0E-02 8.6E-07 1.0E+00 8.6E-07

Debris Flows Unnamed Channel 641.59 641.59 1.0E+00 5.5E-03 1.0E+00 2.0E-02 2.5E-02 2.7E-06 1.0E+00 2.7E-06

Debris Flows Unnamed Fan 641.59 641.64 1.0E+00 5.5E-03 1.0E+00 1.6E-02 1.0E-02 8.6E-07 1.0E+00 8.6E-07

Debris Flows Unnamed Fan 641.64 641.95 1.0E+00 1.7E-03 1.0E+00 9.8E-03 5.0E-02 8.5E-07 1.0E+00 8.5E-07

Debris Flows Unnamed Fan 641.95 642.09 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 8.0E-06 1.0E+00 8.0E-06

Debris Flows Unnamed Channel 642.09 642.1 1.0E+00 5.5E-03 1.0E+00 2.6E-02 2.5E-02 3.5E-06 1.0E+00 3.5E-06

Debris Flows Unnamed Fan 642.1 642.17 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 8.0E-06 1.0E+00 8.0E-06

Debris Flows Unnamed Channel 642.17 642.18 1.0E+00 5.5E-03 1.0E+00 2.0E-03 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 642.18 642.28 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 8.0E-06 1.0E+00 8.0E-06

Debris Flows Unnamed Fan 642.35 642.38 1.0E+00 1.7E-02 1.0E+00 7.7E-03 1.0E-02 1.3E-06 1.0E+00 1.3E-06

Debris Flows Unnamed Channel 642.38 642.38 1.0E+00 1.7E-02 1.0E+00 1.7E-02 5.0E-03 1.5E-06 1.0E+00 1.5E-06

Debris Flows Unnamed Fan 642.38 642.59 1.0E+00 1.7E-02 1.0E+00 7.7E-03 1.0E-02 1.3E-06 1.0E+00 1.3E-06

Lateral Erosion Sundt Creek 643.26 643.27 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Scour (Local) Sundt Creek 643.26 643.27 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 8.0E-01 4.0E-07

Debris Floods Sundt Creek 643.26 643.27 1.0E+00 1.7E-02 1.0E+00 3.3E-02 5.0E-03 2.8E-06 2.4E-01 6.8E-07

Debris Flows Unnamed Fan 643.8 643.83 1.0E+00 5.5E-03 1.0E+00 1.3E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) North Thompson River 643.83 644.08 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Page 24 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Fan 643.95 643.96 1.0E+00 5.5E-03 1.0E+00 1.3E-03 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Tum Tum Fan 644.08 644.09 1.0E+00 5.5E-03 1.0E+00 2.4E-03 5.0E-03 <1.0E-7 5.8E-02 <1.0E-7

Debris Floods Tum Tum Creek 644.09 644.09 1.0E+00 5.5E-03 1.0E+00 2.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7 Avulsion Channel

Debris Floods Tum Tum Fan 644.09 644.16 1.0E+00 5.5E-03 1.0E+00 2.4E-03 5.0E-03 <1.0E-7 5.8E-02 <1.0E-7

Debris Floods Tum Tum Creek 644.16 644.17 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Tum Tum Fan 644.17 644.3 1.0E+00 5.5E-03 1.0E+00 2.4E-03 5.0E-03 <1.0E-7 5.8E-02 <1.0E-7

Debris Floods Tum Tum Creek 644.3 644.32 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E+00 2.7E-07 Channel 1

Debris Floods Tum Tum Fan 644.32 644.45 1.0E+00 5.5E-03 1.0E+00 2.4E-03 5.0E-03 <1.0E-7 5.8E-02 <1.0E-7

Debris Flows Unnamed Fan 644.45 644.5 1.0E+00 5.5E-03 1.0E+00 7.5E-03 1.0E-02 4.1E-07 3.7E-01 1.5E-07

Debris Flows Unnamed Channel 644.5 644.5 1.0E+00 5.5E-03 1.0E+00 2.0E-02 2.5E-02 2.7E-06 1.0E+00 2.7E-06

Debris Flows Unnamed Fan 644.5 644.66 1.0E+00 5.5E-03 1.0E+00 7.5E-03 1.0E-02 4.1E-07 1.0E+00 4.1E-07

Scour (Flooding) North Thompson River 644.66 644.66 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Flows Unnamed Fan 644.66 644.94 1.0E+00 5.5E-03 1.0E+00 1.8E-02 1.0E-02 9.8E-07 1.0E+00 9.8E-07

Debris Flows Unnamed Channel 644.94 644.94 1.0E+00 5.5E-03 1.0E+00 2.0E-02 5.0E-03 5.5E-07 1.0E+00 5.5E-07

Debris Flows Unnamed Fan 644.94 645.19 1.0E+00 5.5E-03 1.0E+00 1.8E-02 1.0E-02 9.8E-07 1.0E+00 9.8E-07

Debris Flows Unnamed Channel 645.19 645.2 1.0E+00 5.5E-03 1.0E+00 3.0E-02 2.5E-02 4.1E-06 1.0E+00 4.1E-06

Debris Flows Unnamed Fan 645.2 645.39 1.0E+00 5.5E-03 1.0E+00 1.8E-02 1.0E-02 9.8E-07 1.0E+00 9.8E-07

Rock Slide Groundhog Mountain - 645.44 646.2 1.0E+00 6.0E-04 1.0E-02 1.0E-01 1.0E+00 6.0E-07 1.0E+00 6.0E-07 Avola

Scour (Flooding) North Thompson River 646.2 647.66 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion North Thompson River 646.25 647.69 1.0E+00 4.9E-03 1.0E+00 1.0E+00 3.0E-02 1.5E-04 1.0E-03 1.5E-07 (Bank Erosion)

Scour (Local) North Thompson River 646.25 647.69 1.0E+00 1.9E-03 1.0E+00 1.0E+00 3.0E-02 5.7E-05 1.0E-03 <1.0E-7

Avulsion North Thompson River 646.25 647.69 1.0E+00 1.1E-02 1.0E+00 1.0E-04 3.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Rodney Creek 647.94 647.95 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 3.4E-02 <1.0E-7

Scour (Local) Unnamed Channel 647.94 647.95 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Channel 648.11 648.11 1.0E+00 1.7E-03 1.0E+00 3.8E-02 5.0E-03 3.3E-07 1.0E+00 3.3E-07

Debris Floods Unnamed Channel 648.27 648.28 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 648.58 648.58 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 8.0E-01 2.0E-07

Page 25 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Denger Creek 648.58 648.58 1.0E+00 1.7E-03 1.0E+00 2.8E-01 5.0E-03 2.4E-06 6.7E-01 1.6E-06

Debris Floods Unnamed Channel 649.08 649.09 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 649.14 649.15 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Field Creek 649.17 649.18 1.0E+00 5.5E-03 1.0E+00 1.2E-02 5.0E-03 3.4E-07 1.0E+00 3.4E-07

Debris Flows Unnamed Channel 649.63 649.63 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 649.9 649.9 1.0E+00 5.5E-03 1.0E+00 2.0E-03 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Avola Creek 651.34 651.34 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Avola Creek 651.34 651.34 1.0E+00 1.7E-03 1.0E+00 3.6E-02 1.0E-04 <1.0E-7 7.5E-01 <1.0E-7

Scour (Flooding) North Thompson River 651.36 652.25 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) North Thompson River 652.76 655.04 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Unnamed Channel 654.18 654.5 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Rainbow Creek Fan 654.18 654.46 1.0E+00 1.7E-02 1.0E+00 7.8E-02 5.0E-03 6.7E-06 2.9E-01 2.0E-06

Debris Floods Rainbow Creek 654.46 654.47 1.0E+00 1.7E-02 1.0E+00 4.7E-02 2.5E-02 2.0E-05 1.7E-01 3.5E-06

Debris Floods Rainbow Creek Fan 654.47 654.5 1.0E+00 1.7E-02 1.0E+00 7.8E-02 5.0E-03 6.7E-06 2.9E-01 2.0E-06

Debris Floods Unnamed Fan 656.31 656.36 1.0E+00 1.7E-02 1.0E+00 8.1E-02 1.0E-04 1.4E-07 7.7E-01 1.1E-07

Debris Floods Unnamed Channel 656.36 656.36 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 656.36 656.48 1.0E+00 1.7E-02 1.0E+00 8.1E-02 1.0E-04 1.4E-07 7.7E-01 1.1E-07

Scour (Flooding) North Thompson River 656.48 657.1 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Flows Unnamed Fan 657.1 657.54 1.0E+00 1.7E-03 1.0E+00 1.6E-02 5.0E-02 1.4E-06 7.7E-01 1.1E-06

Scour (Flooding) North Thompson River 657.53 657.82 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Unnamed Channel 658.57 658.61 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 8.0E-01 1.5E-07

Lateral Erosion Unnamed Channel 658.57 658.61 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Debris Floods Ehlers Creek 658.57 658.61 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-03 8.7E-07 1.0E-02 <1.0E-7

Debris Floods Unnamed Channel 659.7 659.7 1.0E+00 1.7E-02 1.0E+00 2.3E-01 1.0E-04 4.0E-07 1.0E+00 4.0E-07

Scour (Local) Unnamed Channel 659.71 659.72 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Sager Creek 659.8 659.8 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 8.0E-01 1.5E-07

Debris Floods Sager Creek 659.8 659.82 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-03 8.7E-07 2.9E-01 2.5E-07

Debris Floods Unnamed Channel 659.86 659.87 1.0E+00 5.5E-03 1.0E+00 3.3E-02 5.0E-03 8.9E-07 1.0E+00 8.9E-07

Page 26 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Unnamed Channel 660.2 660.23 1.0E+00 5.5E-03 1.0E+00 6.3E-03 5.0E-03 1.7E-07 1.0E+00 1.7E-07

Scour (Local) Bearpark Creek 661.86 661.87 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Bearpaw Creek 661.86 661.87 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 9.0E-01 <1.0E-7

Earth Landslide KP 664 North - 663.34 665.36 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 McMurphy

Rockfall RK 664 Cut Slope - 664.24 664.44 1.0E+00 1.0E-01 1.0E-02 1.0E-03 1.0E-01 1.0E-07 1.0E+00 1.0E-07 McMurphy

Earth Landslide KP 664 Slide - 664.45 664.65 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 McMurphy

Earth Landslide KP 664 South - 664.65 665.37 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 McMurphy

Scour (Flooding) North Thompson River 665.02 665.18 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) North Thompson River 665.3 666.62 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Ivy Creek 667.49 667.5 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Ivy Creek 667.49 667.5 1.0E+00 5.5E-03 1.0E+00 3.3E-02 1.0E-04 <1.0E-7 3.2E-01 <1.0E-7

Debris Floods Unnamed Channel 667.65 667.66 1.0E+00 5.5E-03 1.0E+00 1.0E-01 5.0E-03 2.7E-06 1.0E+00 2.7E-06

Scour (Local) Unnamed Channel 670.2 670.2 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Hornet Creek 670.54 670.54 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 670.54 670.54 1.0E+00 1.7E-03 1.0E+00 7.2E-02 2.5E-02 3.1E-06 5.6E-01 1.7E-06

Scour (Local) Cormet Creek 671.47 671.48 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Jake Creek 673.82 673.82 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Local) Jake Creek 673.82 673.82 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 673.82 673.82 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 6.8E-02 <1.0E-7

Debris Flows Unnamed Fan 676.16 676.45 1.0E+00 5.5E-03 1.0E+00 8.9E-03 1.0E-02 4.9E-07 1.0E+00 4.9E-07

Debris Flows Unnamed Fan 676.8 677.1 1.0E+00 5.5E-03 1.0E+00 1.1E-02 5.0E-02 3.0E-06 1.0E+00 3.0E-06

Debris Flows Unnamed Fan 678.05 678.46 1.0E+00 5.5E-03 1.0E+00 1.4E-02 1.0E-02 7.6E-07 1.0E+00 7.6E-07

Lateral Erosion Mad River 678.81 678.83 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Mad River 678.81 678.83 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Mad River 678.81 678.83 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-03 8.7E-07 1.0E-02 <1.0E-7

Scour (Flooding) Blackberg Creek 678.81 678.91 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Unnamed Channel 680.62 680.62 1.0E+00 1.7E-03 1.0E+00 1.3E-01 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Page 27 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Unnamed Channel 680.72 680.72 1.0E+00 5.5E-03 1.0E+00 2.8E-01 1.0E-04 1.5E-07 9.0E-01 1.4E-07

Scour (Local) Unnamed Channel 680.72 680.72 1.0E+00 2.5E-03 1.0E+00 1.0E+00 5.0E-05 1.3E-07 8.0E-01 1.0E-07

Debris Floods Unnamed Channel 681.23 681.23 1.0E+00 5.5E-03 1.0E+00 2.2E-01 1.0E-04 1.2E-07 8.5E-01 1.0E-07

Scour (Local) Swale 681.23 681.23 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Cove Creek 681.93 681.94 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Cove Creek 681.93 681.94 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Cove Creek 681.93 681.94 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.9E-01 <1.0E-7

Scour (Local) Divide Creek 682.53 682.53 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Bill Creek 683.76 683.8 1.0E+00 5.5E-03 1.0E+00 3.2E-03 2.5E-02 4.4E-07 1.0E+00 4.4E-07

Scour (Local) Blackberg Creek 684.32 684.33 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Blackberg Creek 684.34 684.38 1.0E+00 5.5E-03 1.0E+00 1.9E-02 2.5E-02 2.6E-06 1.0E+00 2.6E-06

Debris Flows Unnamed Channel 686.58 686.59 1.0E+00 1.7E-03 1.0E+00 3.4E-03 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Montanna Creek 687.32 687.32 1.0E+00 2.5E-03 1.0E+00 1.0E+00 5.0E-05 1.3E-07 1.0E+00 1.3E-07

Debris Floods Montanna Creek 687.33 687.34 1.0E+00 1.7E-02 1.0E+00 2.3E-01 1.0E-04 4.0E-07 1.0E+00 4.0E-07

Debris Floods Unnamed Channel 687.53 687.53 1.0E+00 1.7E-03 1.0E+00 1.3E-01 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Earth Landslide Hoirup Road Slopes - 688.38 688.58 1.0E+00 1.0E+00 1.0E-04 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 Vavenby

Earth Landslide Peavine Creek Slopes 697.52 697.68 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05

Debris Floods Peavine Creek 697.6 697.61 1.0E+00 1.7E-02 1.0E+00 3.2E-01 1.0E-04 5.6E-07 7.1E-01 4.0E-07

Scour (Local) Peavine Creek 697.67 697.67 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Slate Creek 699.93 699.95 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 703.53 703.55 1.0E+00 5.5E-03 1.0E+00 4.5E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Crossing Creek 703.58 703.59 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 1.0E+00 2.5E-07

Debris Floods Crossing Creek 703.58 703.59 1.0E+00 1.7E-02 1.0E+00 2.7E-02 1.0E-04 <1.0E-7 2.9E-01 <1.0E-7

Scour (Local) Noblequartz Creek 706.54 706.55 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Noblequartz Creek 706.54 706.55 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 2.5E-01 <1.0E-7

Debris Floods Unnamed Channel 706.69 706.7 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E+00 2.7E-07

Lateral Erosion Raft River 713.29 713.38 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Raft River 713.29 713.38 1.0E+00 2.0E-03 1.0E+00 1.0E+00 6.0E-03 1.2E-05 1.0E-03 <1.0E-7

Scour (Flooding) Raft River 713.32 713.42 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Page 28 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) School Creek 715.5 715.55 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 715.5 715.55 1.0E+00 1.7E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E-02 <1.0E-7

Lateral Erosion School Creek 715.5 715.55 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Local) Clearwater River 721.29 721.41 1.0E+00 1.9E-03 1.0E+00 1.0E+00 3.0E-02 5.7E-05 1.0E-03 <1.0E-7

Lateral Erosion Clearwater River 721.29 721.41 1.0E+00 4.9E-03 1.0E+00 1.0E+00 3.0E-02 1.5E-04 1.0E-03 1.5E-07 (Bank Erosion)

Scour (Flooding) Clearwater River 721.3 721.4 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) North Thompson River 727.13 732.6 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Mann Creek 730.47 730.56 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Avulsion Mann Creek 730.47 730.56 1.0E+00 2.3E-03 1.0E+00 1.0E-04 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Mann Creek 730.47 730.56 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 1.0E-03 <1.0E-7

Debris Flows Blackpool Hill Creek 732.6 732.73 1.0E+00 5.5E-03 1.0E+00 2.7E-03 1.0E-02 1.5E-07 8.8E-02 <1.0E-7 Fan

Debris Flows Blackpool Hill Creek 1 732.73 732.73 1.0E+00 5.5E-03 1.0E+00 8.7E-03 2.5E-02 1.2E-06 1.0E+00 1.2E-06

Debris Flows Blackpool Hill Creek 732.73 732.76 1.0E+00 5.5E-03 1.0E+00 2.7E-03 1.0E-02 1.5E-07 8.8E-02 <1.0E-7 Fan

Debris Flows Blackpool Hill Creek 732.86 732.88 1.0E+00 5.5E-03 1.0E+00 8.8E-04 1.0E-02 <1.0E-7 8.8E-02 <1.0E-7 Fan

Debris Flows Blackpool Hill Creek 732.88 732.88 1.0E+00 1.7E-02 1.0E+00 1.1E-02 2.5E-02 4.6E-06 1.0E+00 4.6E-06

Debris Flows Blackpool Hill Creek 732.88 732.92 1.0E+00 5.5E-03 1.0E+00 8.8E-04 1.0E-02 <1.0E-7 8.8E-02 <1.0E-7 Fan

Debris Slides Blackpool West Slope 732.97 733.47 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06

Debris Floods Unnamed Fan 734.45 734.71 1.0E+00 5.5E-03 1.0E+00 7.0E-03 5.0E-03 1.9E-07 1.0E+00 1.9E-07

Earth Landslide Skwilatin - Relict 738.02 738.52 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E-01 1.0E-06 landslide

Debris Slides Skwilatin S5 Toe 738.55 738.58 1.0E+00 1.0E-01 1.0E-02 1.0E+00 1.0E-02 1.0E-05 1.5E-01 1.5E-06 Slopes - Blackpool

Rockfall Mount Loveway - 742.94 743.29 1.0E+00 1.0E-02 1.0E-04 5.0E-01 1.0E+00 5.0E-07 1.0E+00 5.0E-07 Little Fort

Debris Flows Mt. Loveway Fan 1 743.16 743.74 1.0E+00 5.5E-03 1.0E+00 4.1E-03 5.0E-02 1.1E-06 1.0E+00 1.1E-06

Rock Slide Mount Loveway - 743.19 743.29 1.0E+00 8.0E-05 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 1.0E+00 <1.0E-7 Little Fort

Debris Flows Mt. Loveway Fan 2 744.02 744.26 1.0E+00 5.5E-03 1.0E+00 6.8E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Mt. Loveway Fan 3 744.26 744.5 1.0E+00 5.5E-03 1.0E+00 4.7E-03 5.0E-02 1.3E-06 1.0E+00 1.3E-06

Scour (Flooding) Lemieux Creek 744.5 744.83 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Page 29 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Lateral Erosion Lemieux Creek 744.71 744.83 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 2.4E-01 7.1E-06 (Bank Erosion)

Scour (Local) Lemieux Creek 744.71 744.83 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Debris Floods Lemieux Creek 744.71 744.83 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Unnamed Channel 744.83 744.95 1.0E+00 5.5E-03 1.0E+00 1.0E-01 5.0E-03 2.7E-06 1.0E+00 2.7E-06

Scour (Flooding) Lemieux Creek 745.91 746.12 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Nehalliston Creek 746.42 746.46 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Avulsion Nehalliston Creek 746.42 746.46 1.0E+00 4.4E-01 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Nehalliston Creek 746.42 746.46 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Nehalliston Creek 746.42 746.46 1.0E+00 5.5E-02 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.9E-02 <1.0E-7

Scour (Flooding) Lemieux Creek 747.22 747.33 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Lemieux Creek 747.79 748.08 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Eakin Creek 747.83 747.85 1.0E+00 4.9E-03 1.0E+00 1.0E+00 5.0E-04 2.4E-06 8.0E-01 2.0E-06 (Bank Erosion)

Scour (Local) Eakin Creek 747.83 747.85 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-04 2.5E-06 8.0E-01 2.0E-06

Debris Floods Eakin Creek 747.83 747.85 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 8.0E-01 <1.0E-7

Scour (Flooding) Lemieux Creek 748.57 749.27 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Rockfall Caverhill - Little Fort 752.54 752.91 1.0E+00 1.0E-02 1.0E-02 5.0E-01 1.0E+00 5.0E-05 3.0E-02 1.5E-06

Lateral Erosion Montigny Creek 753.33 753.43 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Montigny Creek 753.33 753.43 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Montigny Creek 753.33 753.43 1.0E+00 1.7E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 9.8E-02 <1.0E-7

Scour (Flooding) North Thompson River 753.68 755.54 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Flows Unnamed Channel 755.73 755.73 1.0E+00 5.5E-03 1.0E+00 9.0E-03 2.5E-02 1.2E-06 1.0E+00 1.2E-06

Scour (Flooding) Thuya Creek 756.42 756.58 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Thuya Creek 756.64 756.66 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 8.0E-01 4.0E-07

Debris Floods Unnamed Channel 756.64 756.66 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 3.5E-01 <1.0E-7

Lateral Erosion Thuya Creek 756.64 756.66 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Debris Floods Unnamed Channel 758.24 758.24 1.0E+00 1.7E-03 1.0E+00 8.1E-02 2.5E-02 3.5E-06 1.0E+00 3.5E-06

Debris Floods Unnamed Fan 763.14 763.19 1.0E+00 1.7E-02 1.0E+00 1.5E-02 5.0E-03 1.3E-06 2.0E-01 2.6E-07

Debris Floods Unnamed Channel 763.19 763.2 1.0E+00 1.7E-02 1.0E+00 2.3E-01 1.0E-04 3.9E-07 1.0E+00 3.9E-07

Page 30 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Unnamed Fan 763.2 763.23 1.0E+00 1.7E-02 1.0E+00 1.5E-02 5.0E-03 1.3E-06 2.0E-01 2.6E-07

Debris Floods Darlington Creek Fan 763.6 763.71 1.0E+00 5.5E-03 1.0E+00 6.1E-02 5.0E-03 1.7E-06 4.9E-01 8.3E-07

Lateral Erosion Darlington Creek 763.71 763.83 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Avulsion Darlington Creek 763.71 763.83 1.0E+00 1.8E-01 1.0E+00 5.0E-03 1.0E-04 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Darlington Creek 763.71 763.83 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 8.0E-01 4.0E-07

Debris Floods Darlington Creek Fan 763.71 763.77 1.0E+00 5.5E-03 1.0E+00 6.1E-02 5.0E-03 1.7E-06 2.1E-01 3.6E-07

Debris Floods Darlington Creek 763.77 763.78 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 9.0E-01 <1.0E-7

Debris Floods Darlington Creek Fan 763.78 763.83 1.0E+00 5.5E-03 1.0E+00 6.1E-02 5.0E-03 1.7E-06 2.1E-01 3.6E-07

Debris Floods Darlington Creek Fan 763.83 763.9 1.0E+00 5.5E-03 1.0E+00 6.1E-02 5.0E-03 1.7E-06 4.9E-01 8.3E-07

Scour (Flooding) North Thompson River 764.05 764.56 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Powder Creek Fan 764.05 764.07 1.0E+00 1.7E-03 1.0E+00 1.7E-02 5.0E-03 1.5E-07 2.2E-01 <1.0E-7

Lateral Erosion Lindquist Creek 764.07 764.09 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Lindquist Creek 764.07 764.09 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Powder Creek 764.07 764.09 1.0E+00 1.7E-03 1.0E+00 6.7E-02 5.0E-03 5.8E-07 5.1E-01 3.0E-07

Debris Floods Powder Creek Fan 764.09 764.12 1.0E+00 1.7E-03 1.0E+00 1.7E-02 5.0E-03 1.5E-07 2.2E-01 <1.0E-7

Debris Flows Unnamed Fan 806.68 807.19 1.0E+00 1.7E-03 1.0E+00 3.6E-02 5.0E-02 3.1E-06 1.0E+00 3.1E-06

Debris Flows Unnamed Fan 807.19 807.89 1.0E+00 1.7E-03 1.0E+00 1.4E-02 1.0E-02 2.4E-07 1.0E+00 2.4E-07

Scour (Flooding) Jamieson Creek 816.04 816.4 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Jamieson Creek Fan 816.04 816.25 1.0E+00 5.5E-03 1.0E+00 4.4E-02 2.5E-02 6.1E-06 1.0E+00 6.1E-06

Lateral Erosion Jamieson Creek 816.25 816.31 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-05 1.0E-07 8.0E-01 <1.0E-7 (Bank Erosion)

Avulsion Jamieson Creek 816.25 816.31 1.0E+00 6.0E-01 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Jamieson Creek 816.25 816.31 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Jamieson Creek Fan 816.25 816.31 1.0E+00 5.5E-03 1.0E+00 4.4E-02 2.5E-02 6.1E-06 4.1E-01 2.5E-06

Debris Floods Jamieson Creek Fan 816.31 816.4 1.0E+00 5.5E-03 1.0E+00 4.4E-02 2.5E-02 6.1E-06 1.0E+00 6.1E-06

Earth Landslide Lanes Creek North 821.38 821.58 1.0E+00 1.0E-01 1.0E-01 1.0E+00 1.0E-02 1.0E-04 8.0E-02 8.0E-06 East Slope - Kamloops

Scour (Local) Lanes Creek 821.54 821.54 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Lanes Creek 821.54 821.54 1.0E+00 1.7E-03 1.0E+00 5.8E-02 5.0E-03 5.1E-07 4.9E-01 2.5E-07

Page 31 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rockfall Dairy Creek Slopes - 824.12 824.42 1.0E+00 1.0E-01 1.0E-04 1.0E-02 1.0E+00 1.0E-07 1.0E+00 1.0E-07 Kamloops

Scour (Local) Dairy Creek 824.37 824.38 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Dairy Creek 824.37 824.38 1.0E+00 1.7E-03 1.0E+00 1.0E-02 1.0E-05 <1.0E-7 3.4E-02 <1.0E-7

Scour (Local) McQueen Creek 825.08 825.08 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods McQueen Creek 825.08 825.08 1.0E+00 1.7E-03 1.0E+00 3.3E-02 1.0E-05 <1.0E-7 2.3E-01 <1.0E-7

Debris Floods Unnamed Channel 831.97 831.98 1.0E+00 1.7E-03 1.0E+00 3.7E-02 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 832.82 832.84 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Old Pipe Creek Gully 833.14 833.17 1.0E+00 1.7E-03 1.0E+00 4.4E-01 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 833.73 833.74 1.0E+00 1.7E-03 1.0E+00 3.3E-02 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 833.85 833.86 1.0E+00 5.5E-03 1.0E+00 1.4E-01 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Lac Du Bois Gully 1 834.65 834.66 1.0E+00 5.5E-03 1.0E+00 1.5E-01 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Lac Du Bois Gully 2 834.82 834.83 1.0E+00 5.5E-03 1.0E+00 4.2E-01 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Thompson River 840.85 843.57 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-02 2.9E-04 1.0E-03 2.9E-07 (Bank Erosion)

Scour (Local) Thompson River 840.85 843.57 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-02 1.1E-04 1.0E-03 1.1E-07

Scour (Flooding) Thompson River 842.64 843.58 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Peterson Creek 854.72 854.72 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Anderson Creek 861.46 861.5 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Anderson Creek 861.46 861.5 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Droppingwater Creek 870.63 870.64 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Droppingwater Creek 870.63 870.64 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Flooding) Stump Lake Tributary 4 883.3 883.48 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Slides Moore Creek East 889.28 889.36 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-03 1.0E-07 1.0E+00 1.0E-07 Slope

Scour (Flooding) Moore Creek 889.32 889.4 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Moore Creek 889.34 889.4 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Debris Floods Moore Creek 889.34 889.4 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 9.0E-01 <1.0E-7

Scour (Local) Moore Creek 889.34 889.4 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Avulsion Moore Creek 889.34 889.4 1.0E+00 2.3E-01 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 32 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Slides Moore Creek West 889.42 889.48 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-03 1.0E-07 1.0E+00 1.0E-07 Slope

Debris Floods Unnamed Channel 889.89 889.91 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Cultus Creek 890.02 890.05 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 893.33 893.34 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Rockfall Nicola Lake Bluffs - 893.55 894.74 1.0E+00 1.0E-03 1.0E-03 1.0E-01 1.0E+00 1.0E-07 1.0E+00 1.0E-07 Quilchena

Debris Floods Unnamed Fan 894.91 894.96 1.0E+00 1.7E-03 1.0E+00 4.6E-10 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 894.96 894.96 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 894.96 894.97 1.0E+00 1.7E-03 1.0E+00 4.6E-10 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Rocky Gulch 896.85 896.85 1.0E+00 1.7E-03 1.0E+00 1.5E-02 2.5E-02 6.6E-07 5.6E-01 3.7E-07

Scour (Local) Rocky Gulch 896.85 896.85 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Klup Creek 899.82 899.82 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Klup Creek 899.82 899.82 1.0E+00 1.7E-03 1.0E+00 1.7E-01 2.5E-02 7.5E-06 5.8E-01 4.4E-06

Earth Landslide Quilchena North Slopes 904.87 905.57 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-03 1.0E-07 1.0E+00 1.0E-07

Scour (Flooding) Clapperton Creek 912.57 912.68 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Clapperton Creek 912.61 912.64 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-03 5.0E-06 1.0E+00 5.0E-06

Lateral Erosion Clapperton Creek 912.61 912.64 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-03 4.9E-06 1.0E+00 4.9E-06 (Bank Erosion)

Debris Floods Shuta Creek 915 915.01 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 8.8E-02 <1.0E-7

Scour (Local) Shuta Creek 915 915.01 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Avulsion Nicola River 924.44 924.74 1.0E+00 2.3E-02 1.0E+00 1.0E-04 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Nicola River 924.44 924.74 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Nicola River 924.44 924.74 1.0E+00 2.0E-03 1.0E+00 1.0E+00 6.0E-03 1.2E-05 1.0E-03 <1.0E-7

Scour (Flooding) Nicola River 924.46 924.74 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Hamilton Creek 925.4 925.52 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Kwinshatin Creek 938.03 938.03 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Floods Kwinshatin Creek 938.03 938.03 1.0E+00 1.7E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 7.9E-02 <1.0E-7

Debris Floods Unnamed Channel 938.12 938.12 1.0E+00 1.7E-03 1.0E+00 1.0E-01 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 938.28 938.28 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 8.0E-01 2.0E-07

Debris Floods Unnamed Channel 938.28 938.28 1.0E+00 1.7E-03 1.0E+00 1.7E-01 1.0E-04 <1.0E-7 6.1E-01 <1.0E-7

Page 33 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Salem Creek 945.85 945.85 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 9.6E-01 <1.0E-7

Scour (Local) Salem Creek 945.85 945.85 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Coldwater River 953.58 954.53 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Coldwater River 953.58 954.53 1.0E+00 2.5E-03 1.0E+00 1.0E+00 6.0E-03 1.5E-05 1.0E-03 <1.0E-7

Avulsion Coldwater River 953.58 954.53 1.0E+00 1.1E-03 1.0E+00 1.0E-04 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Coldwater River 953.59 954.64 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Gillis Creek Fan 954.64 954.65 1.0E+00 5.5E-03 1.0E+00 1.3E-02 5.0E-03 3.5E-07 1.8E-01 <1.0E-7

Lateral Erosion Gillis Creek 954.65 954.69 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 (Bank Erosion)

Debris Floods Gillis Creek 954.65 954.69 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Gillis Creek 954.65 954.69 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7

Avulsion Gillis Creek 954.65 954.69 1.0E+00 2.3E-01 1.0E+00 1.0E-04 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Debris Floods Gillis Creek Fan 954.69 954.74 1.0E+00 5.5E-03 1.0E+00 1.3E-02 5.0E-03 3.5E-07 1.8E-01 <1.0E-7

Earth Landslide Gillis Creek South 954.98 955.8 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-01 1.0E-04 4.3E-02 4.3E-06 Slope - Kingsvale

Earth Landslide Kingsvale Creek Slopes 957 957.24 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06

Debris Floods Kingsvale Creek 957.14 957.14 1.0E+00 5.5E-03 1.0E+00 3.3E-02 1.0E-04 <1.0E-7 3.3E-01 <1.0E-7

Scour (Local) Kingsvale Creek 957.14 957.14 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Earth Landslide Fig Lake Slope - 958.41 958.66 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-01 1.0E-05 Kingsvale

Scour (Local) Unnamed Channel 958.55 958.56 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 1.0E+00 5.0E-07

Debris Floods Fig Peak Creek 958.55 958.56 1.0E+00 1.7E-03 1.0E+00 3.3E-02 5.0E-03 2.8E-07 1.2E-01 <1.0E-7

Lateral Erosion Unnamed Channel 958.55 958.56 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 1.0E+00 4.9E-07 (Bank Erosion)

Scour (Local) Unnamed Channel 961.98 962 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 961.98 962 1.0E+00 1.7E-03 1.0E+00 1.7E-02 1.0E-04 <1.0E-7 3.7E-01 <1.0E-7

Scour (Local) Unnamed Channel 966.24 966.24 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Coldwater River 966.48 966.96 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Coldwater River 966.83 966.97 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Coldwater River 966.83 966.97 1.0E+00 2.0E-03 1.0E+00 1.0E+00 6.0E-03 1.2E-05 1.0E-03 <1.0E-7

Avulsion Coldwater River 966.83 966.97 1.0E+00 6.0E-03 1.0E+00 1.0E-04 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Page 34 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Unnamed Fan 967.21 967.24 1.0E+00 5.5E-03 1.0E+00 1.4E-01 2.5E-02 2.0E-05 4.1E-01 8.0E-06

Debris Floods Unnamed Channel 967.24 967.24 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 1.0E-03 <1.0E-7

Debris Floods Unnamed Fan 967.24 967.26 1.0E+00 5.5E-03 1.0E+00 1.4E-01 2.5E-02 2.0E-05 4.1E-01 8.0E-06

Scour (Local) Unnamed Channel 967.24 967.24 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7

Debris Floods Unnamed Channel 970.29 970.29 1.0E+00 5.5E-03 1.0E+00 5.4E-02 2.5E-02 7.4E-06 5.6E-01 4.2E-06

Scour (Local) Unnamed Channel 970.29 970.29 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Flooding) Coldwater River 970.86 970.94 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Coldwater River 971.18 972.39 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Flows Unnamed Channel 972.91 972.91 1.0E+00 5.5E-03 1.0E+00 1.8E-03 5.0E-02 4.9E-07 1.0E+00 4.9E-07

Debris Flows Unnamed Fan 973.18 973.35 1.0E+00 5.5E-03 1.0E+00 3.2E-02 5.0E-02 8.8E-06 1.0E+00 8.8E-06

Debris Flows Unnamed Channel 973.35 973.36 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-02 2.8E-06 1.0E+00 2.8E-06

Debris Flows Unnamed Fan 973.36 973.43 1.0E+00 5.5E-03 1.0E+00 3.2E-02 5.0E-02 8.8E-06 1.0E+00 8.8E-06

Scour (Flooding) Coldwater River 975.16 975.29 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Unnamed Channel 975.27 975.27 1.0E+00 5.5E-03 1.0E+00 3.3E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Avulsion Coldwater River 976.16 976.78 1.0E+00 3.0E-02 1.0E+00 1.0E-04 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Coldwater River 976.16 976.78 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Local) Coldwater River 976.16 976.78 1.0E+00 3.3E-03 1.0E+00 1.0E+00 6.0E-03 2.0E-05 1.0E-03 <1.0E-7

Scour (Flooding) Coldwater River 976.28 976.85 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Coldwater River 977.6 978.06 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Juliet Creek 977.64 977.67 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-05 1.0E-07 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Juliet Creek 977.64 977.67 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Avulsion Juliet Creek 977.64 977.67 1.0E+00 1.5E-04 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 982.11 982.12 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Earth Landslide Jim Kelly Gully Slopes - 982.59 982.79 1.0E+00 1.0E-01 1.0E-01 1.0E+00 1.0E-02 1.0E-04 1.0E-01 1.0E-05 Coquihalla Summit

Scour (Local) Unnamed Channel 982.66 982.67 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Avulsion Mine Creek 983.71 984.09 1.0E+00 1.5E-03 1.0E+00 2.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Mine Creek 983.71 984.09 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Mine Creek 983.71 984.09 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 35 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Mine Creek Fan 983.71 983.94 1.0E+00 5.5E-03 1.0E+00 8.9E-02 2.5E-02 1.2E-05 6.2E-01 7.5E-06

Debris Floods Mine Creek 983.94 983.96 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 9.0E-01 <1.0E-7

Debris Floods Mine Creek Fan 983.96 984.09 1.0E+00 5.5E-03 1.0E+00 8.9E-02 2.5E-02 1.2E-05 6.2E-01 7.5E-06

Debris Floods Mine Creek Fan 984.09 984.17 1.0E+00 5.5E-03 1.0E+00 8.9E-02 2.5E-02 1.2E-05 7.9E-01 9.7E-06

Debris Floods Unnamed Fan 986.15 986.34 1.0E+00 5.5E-03 1.0E+00 5.7E-02 2.5E-02 7.8E-06 1.0E+00 7.8E-06

Debris Floods Unnamed Channel 986.34 986.34 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Fan 986.34 986.37 1.0E+00 5.5E-03 1.0E+00 5.7E-02 2.5E-02 7.8E-06 1.0E+00 7.8E-06

Lateral Erosion Coldwater River 986.88 986.96 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 (Bank Erosion)

Scour (Local) Coldwater River 986.88 986.96 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7

Avulsion Coldwater River 986.88 986.96 1.0E+00 2.8E-04 1.0E+00 1.0E-04 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Scour (Flooding) Coldwater River 986.89 986.95 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Unnamed Channel 989.72 989.73 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 992.13 992.13 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 1.0E+00 2.5E-07

Rockfall Dry Gulch East Slope - 992.78 992.89 1.0E+00 1.0E+00 1.0E-01 1.0E-02 5.0E-01 5.0E-04 1.5E-02 7.5E-06 Coquihalla Summit

Rockfall Dry Gulch - Coquihalla 992.89 992.96 1.0E+00 1.0E+00 1.0E-01 1.0E-02 5.0E-01 5.0E-04 1.5E-02 7.5E-06 Summit

Rockfall Dry Gulch West Slope - 992.96 993.07 1.0E+00 1.0E+00 1.0E-01 1.0E-02 5.0E-01 5.0E-04 1.5E-02 7.5E-06 Coquihalla Summit

Outburst Floods Cascade Mountains - 994.11 994.4 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Falls Creek and lake

Debris Floods Unnamed Channel 994.21 994.24 1.0E+00 5.5E-03 1.0E+00 0.0E+00 2.5E-02 <1.0E-7 9.0E-01 <1.0E-7

Scour (Local) Fallslake Creek 994.21 994.24 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-03 5.0E-06 8.0E-01 4.0E-06

Avulsion Fallslake Creek 994.21 994.24 1.0E+00 9.4E-04 1.0E+00 5.0E-03 1.0E-03 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Fallslake Creek 994.21 994.24 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-03 4.9E-06 8.0E-01 3.9E-06 (Bank Erosion)

Debris Slides Coquihalla Summit 994.87 1000 1.0E+00 1.0E-03 1.0E-03 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 Slopes

Rock Slide Thar Peak North - 995.24 995.71 1.0E+00 3.6E-04 1.0E-02 1.0E-01 1.0E+00 3.6E-07 1.0E+00 3.6E-07 Coquihalla Summit

Rock Avalanches Nak Peak - Coquihalla 995.49 996.84 1.0E+00 4.0E-05 5.0E-01 1.0E-01 1.0E+00 1.8E-06 1.0E+00 1.8E-06 Summit

Rock Slide Thar Peak South - 995.71 995.86 1.0E+00 1.3E-04 1.0E-02 1.0E-01 1.0E+00 1.3E-07 1.0E+00 1.3E-07 Coquihalla Summit

Page 36 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Slide Nak Peak North - 995.86 996.05 1.0E+00 1.5E-04 1.0E-02 1.0E-01 1.0E+00 1.5E-07 1.0E+00 1.5E-07 Coquihalla Summit

Debris Flows Nak Peak Channel 995.92 995.92 1.0E+00 1.7E-03 1.0E+00 6.5E-03 2.0E-03 <1.0E-7 2.1E-01 <1.0E-7

Scour (Local) Unnamed Channel 995.92 995.92 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 1.0E+00 2.5E-07

Rock Slide Nak Peak South - 996.05 996.85 1.0E+00 6.3E-04 1.0E-02 1.0E-01 1.0E+00 6.3E-07 1.0E+00 6.3E-07 Coquihalla Summit

Rock Avalanches Markhor Peak North 997.42 998.93 1.0E+00 4.0E-05 5.0E-01 1.0E-01 1.0E+00 2.1E-06 1.0E+00 2.1E-06 Slope - Coquihalla Summit

Scour (Local) Unnamed Channel 998.07 998.07 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Markhor Peak Channel 998.07 998.07 1.0E+00 1.7E-03 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 8.1E-02 <1.0E-7 1

Rock Avalanches Markhor Peak South 998.93 999.64 1.0E+00 2.0E-05 5.0E-01 5.0E-01 1.0E+00 4.8E-06 1.0E+00 4.8E-06 Slope - Coquihalla Summit

Scour (Local) Unnamed Channel 999.37 999.38 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Markhor Peak Channel 999.37 999.38 1.0E+00 5.5E-03 1.0E+00 2.9E-03 5.0E-03 <1.0E-7 4.7E-01 <1.0E-7 2

Debris Flows Markhor Peak Channel 999.47 999.48 1.0E+00 1.7E-03 1.0E+00 6.4E-03 5.0E-03 <1.0E-7 1.0E+00 <1.0E-7 3

Debris Floods Unnamed Channel 1000.04 1000.05 1.0E+00 5.5E-03 1.0E+00 0.0E+00 2.5E-02 <1.0E-7 9.0E-01 <1.0E-7

Scour (Local) Boston Bar Creek 1000.04 1000.05 1.0E+00 2.0E-03 1.0E+00 1.0E+00 5.0E-04 1.0E-06 1.0E+00 1.0E-06

Rockfall Bear Shed Opposite 1001.58 1002.95 1.0E+00 1.0E-03 1.0E-02 5.0E-01 1.0E+00 5.0E-06 1.0E+00 5.0E-06 Slope - Coquihalla Valley

Debris Floods Unnamed Channel 1001.59 1001.6 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-03 2.7E-07 2.4E-01 <1.0E-7

Scour (Local) Unnamed Channel 1001.59 1001.6 1.0E+00 2.0E-03 1.0E+00 1.0E+00 5.0E-04 1.0E-06 1.0E+00 1.0E-06

Lateral Erosion Unnamed Channel 1001.59 1001.6 1.0E+00 4.9E-03 1.0E+00 1.0E+00 5.0E-04 2.4E-06 1.0E+00 2.4E-06 (Bank Erosion)

Avulsion Unnamed Channel 1001.59 1001.6 1.0E+00 1.9E-04 1.0E+00 2.0E-03 5.0E-04 <1.0E-7 1.0E+00 <1.0E-7

Rock Slide Flatiron - Coquihalla 1001.61 1002.87 1.0E+00 1.0E-03 1.0E-02 1.0E-01 1.0E+00 1.0E-06 1.0E+00 1.0E-06 Valley

Debris Slides Flatiron - Coquihalla 1001.62 1007.76 1.0E+00 1.0E+00 1.0E-01 1.0E+00 1.0E-03 1.0E-04 1.0E-01 1.0E-05 Valley

Rock Avalanches Flatiron 1 - Coquihalla 1001.87 1002.87 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 6.9E-06 1.0E+00 6.9E-06 Valley

Debris Flows Unnamed Channel 1002.32 1002.33 1.0E+00 5.5E-03 1.0E+00 3.0E-03 1.0E-02 1.6E-07 1.1E-01 <1.0E-7

Rock Avalanches Flatiron 2 - Coquihalla 1002.87 1005.46 1.0E+00 7.0E-05 5.0E-01 1.0E-01 1.0E+00 3.6E-06 1.0E+00 3.6E-06 Valley

Page 37 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Slide Flatiron - Coquihalla 1002.87 1003.77 1.0E+00 7.1E-04 1.0E-02 1.0E-01 1.0E+00 7.1E-07 1.0E+00 7.1E-07 Valley

Debris Flows Unnamed Fan 1003.65 1003.75 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 3.7E-06 2.8E-01 1.1E-06

Debris Flows Unnamed Channel 1003.75 1003.77 1.0E+00 5.5E-03 1.0E+00 1.0E-03 2.5E-02 1.4E-07 1.4E-01 <1.0E-7

Rock Slide Flatiron - Coquihalla 1003.77 1004.58 1.0E+00 6.4E-04 1.0E-01 1.0E-01 1.0E+00 6.4E-06 1.0E+00 6.4E-06 Valley

Debris Flows Unnamed Fan 1003.77 1003.79 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 3.7E-06 2.8E-01 1.1E-06

Debris Flows Unnamed Channel 1003.79 1003.79 1.0E+00 5.5E-03 1.0E+00 2.0E-03 2.5E-02 2.7E-07 6.1E-02 <1.0E-7

Debris Flows Unnamed Fan 1003.79 1004.01 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 3.7E-06 2.8E-01 1.1E-06

Debris Flows Unnamed Channel 1004.01 1004.02 1.0E+00 5.5E-03 1.0E+00 3.6E-02 1.0E-02 2.0E-06 4.9E-01 9.8E-07

Debris Flows Unnamed Fan 1004.02 1004.11 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 3.7E-06 2.8E-01 1.1E-06

Debris Flows Unnamed Channel 1004.11 1004.11 1.0E+00 5.5E-03 1.0E+00 4.1E-03 1.0E-02 2.2E-07 2.4E-01 <1.0E-7

Debris Flows Unnamed Fan 1004.11 1004.18 1.0E+00 5.5E-03 1.0E+00 1.4E-02 5.0E-02 3.7E-06 2.8E-01 1.1E-06

Rockfall North Flatiron 1004.11 1004.47 1.0E+00 1.0E-03 1.0E-02 5.0E-01 1.0E+00 5.0E-06 1.0E+00 5.0E-06 Mountain - Coquihalla Valley

Debris Floods Jamieson Creek 1004.38 1004.39 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1004.38 1004.39 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 1.0E-02 <1.0E-7

Rock Slide Flatiron - Coquihalla 1004.58 1005.58 1.0E+00 8.0E-04 1.0E-02 1.0E-01 1.0E+00 8.0E-07 1.0E+00 8.0E-07 Valley

Scour (Local) Unnamed Channel 1004.63 1004.64 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1004.63 1004.65 1.0E+00 1.7E-02 1.0E+00 6.5E-03 5.0E-02 5.6E-06 5.1E-01 2.9E-06

Debris Flows Unnamed Channel 1004.66 1004.66 1.0E+00 5.5E-03 1.0E+00 6.1E-03 5.0E-02 1.7E-06 4.1E-01 6.9E-07

Rockfall Flatiron Mountain - 1004.81 1007.92 1.0E+00 1.0E-03 1.0E-03 5.0E-01 1.0E+00 5.0E-07 1.0E+00 5.0E-07 Coquihalla Valley

Debris Flows Unnamed Channel 1005.4 1005.43 1.0E+00 5.5E-03 1.0E+00 2.9E-03 5.0E-02 7.9E-07 3.4E-01 2.7E-07

Debris Flows Unnamed Fan 1005.43 1005.64 1.0E+00 5.5E-03 1.0E+00 1.5E-02 1.0E-02 8.1E-07 6.8E-02 <1.0E-7

Rock Avalanches Flatiron 3 - Coquihalla 1005.46 1006.86 1.0E+00 4.0E-05 5.0E-01 5.0E-01 1.0E+00 9.5E-06 1.0E+00 9.5E-06 Valley

Rock Slide Flatiron - Coquihalla 1005.58 1006.39 1.0E+00 6.4E-04 1.0E-02 1.0E-01 1.0E+00 6.4E-07 1.0E+00 6.4E-07 Valley

Debris Flows Unnamed Channel 1006.23 1006.25 1.0E+00 5.5E-03 1.0E+00 4.1E-03 1.0E-02 2.2E-07 8.8E-01 2.0E-07

Lateral Erosion Unnamed Channel 1006.26 1006.29 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Unnamed Channel 1006.26 1006.29 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Page 38 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Channel 1006.27 1006.28 1.0E+00 1.7E-02 1.0E+00 1.6E-02 5.0E-02 1.4E-05 6.6E-01 9.3E-06

Rock Slide Flatiron - Coquihalla 1006.39 1007.09 1.0E+00 5.6E-04 1.0E-02 1.0E-01 1.0E+00 5.6E-07 1.0E+00 5.6E-07 Valley

Earth Landslide Portia Peak - 1006.49 1006.68 1.0E+00 1.0E-02 1.0E-03 1.0E+00 1.0E-02 1.0E-07 1.0E+00 1.0E-07 Coquihalla Valley

Rock Avalanches Flatiron 4 - Coquihalla 1006.86 1008.16 1.0E+00 4.0E-05 5.0E-01 5.0E-01 1.0E+00 8.8E-06 1.0E+00 8.8E-06 Valley

Rock Slide Flatiron - Coquihalla 1007.09 1007.54 1.0E+00 3.5E-04 1.0E-02 1.0E-01 1.0E+00 3.5E-07 1.0E+00 3.5E-07 Valley

Rock Slide Flatiron - Coquihalla 1007.54 1008.06 1.0E+00 4.0E-04 1.0E-01 1.0E-01 1.0E+00 4.0E-06 1.0E+00 4.0E-06 Valley

Scour (Local) Boston Bar Creek 1008.01 1008.07 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Lateral Erosion Boston Bar Creek 1008.01 1008.07 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 4.0E-01 1.2E-05 (Bank Erosion)

Avulsion Boston Bar Creek 1008.01 1008.07 1.0E+00 9.4E-04 1.0E+00 1.9E-03 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Rock Slide Bombtram Mountain - 1008.06 1008.67 1.0E+00 4.8E-04 1.0E-02 1.0E-01 1.0E+00 4.8E-07 1.0E+00 4.8E-07 Coquihalla Valley

Rockfall Bombtram Mountain - 1008.06 1009.81 1.0E+00 1.0E-03 1.0E-02 5.0E-01 1.0E+00 5.0E-06 1.0E+00 5.0E-06 Coquihalla Valley

Debris Slides Bombtram Mountain - 1008.12 1012.26 1.0E+00 1.0E+00 1.0E-01 1.0E+00 1.0E-03 1.0E-04 1.0E-01 1.0E-05 Coquihalla Valley

Rock Avalanches Bombtram Mountain 1008.16 1009.32 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 7.9E-06 1.0E+00 7.9E-06 1 - Coquihalla Valley

Debris Flows Unnamed Fan 1008.18 1008.2 1.0E+00 1.7E-02 1.0E+00 7.0E-03 5.0E-02 6.1E-06 1.4E-01 8.8E-07

Debris Flows Unnamed Channel 1008.2 1008.22 1.0E+00 5.5E-02 1.0E+00 8.7E-03 1.0E-02 4.8E-06 4.8E-02 2.3E-07

Scour (Local) Unnamed Channel 1008.21 1008.21 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 1008.22 1008.3 1.0E+00 1.7E-02 1.0E+00 7.0E-03 5.0E-02 6.1E-06 1.4E-01 8.8E-07

Debris Flows Unnamed Channel 1008.3 1008.3 1.0E+00 1.7E-02 1.0E+00 4.2E-02 2.5E-02 1.8E-05 5.1E-01 9.3E-06

Debris Flows Unnamed Fan 1008.3 1008.52 1.0E+00 1.7E-02 1.0E+00 7.0E-03 5.0E-02 6.1E-06 1.4E-01 8.8E-07

Debris Flows Unnamed Channel 1008.62 1008.62 1.0E+00 5.5E-03 1.0E+00 4.5E-02 5.0E-02 1.2E-05 8.0E-01 9.8E-06

Debris Flows Unnamed Channel 1008.65 1008.65 1.0E+00 5.5E-03 1.0E+00 3.1E-02 5.0E-02 8.4E-06 7.1E-01 5.9E-06

Rock Slide Bombtram Mountain - 1008.67 1008.98 1.0E+00 2.5E-04 1.0E-02 1.0E-01 1.0E+00 2.5E-07 1.0E+00 2.5E-07 Coquihalla Valley

Rock Slide Bombtram Mountain - 1008.98 1009.81 1.0E+00 6.5E-04 1.0E-02 1.0E-01 1.0E+00 6.5E-07 1.0E+00 6.5E-07 Coquihalla Valley

Page 39 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Unnamed Channel 1008.99 1009 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1009 1009.01 1.0E+00 1.7E-02 1.0E+00 3.0E-02 2.5E-02 1.3E-05 7.2E-01 9.2E-06

Debris Flows Unnamed Fan 1009.01 1009.31 1.0E+00 1.7E-02 1.0E+00 2.6E-03 1.0E-02 4.5E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1009.31 1009.35 1.0E+00 1.7E-02 1.0E+00 1.5E-02 2.5E-02 6.4E-06 3.1E-01 2.0E-06

Rock Avalanches Bombtram Mountain 1009.32 1010.33 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 6.9E-06 1.0E+00 6.9E-06 2 - Coquihalla Valley

Scour (Local) Unnamed Channel 1009.35 1009.37 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1009.35 1009.37 1.0E+00 1.7E-02 1.0E+00 3.6E-02 2.5E-02 1.6E-05 5.9E-01 9.3E-06

Debris Flows Unnamed Fan 1009.37 1009.58 1.0E+00 1.7E-02 1.0E+00 1.5E-02 2.5E-02 6.4E-06 3.1E-01 2.0E-06

Rock Slide Bombtram Mountain - 1009.81 1010.09 1.0E+00 2.2E-04 1.0E-02 1.0E-01 1.0E+00 2.2E-07 1.0E+00 2.2E-07 Coquihalla Valley

Rockfall Coquihalla Valley West 1009.81 1013.17 1.0E+00 1.0E-03 1.0E-03 5.0E-01 1.0E+00 5.0E-07 1.0E+00 5.0E-07 Slopes

Debris Flows Unnamed Fan 1009.83 1009.9 1.0E+00 1.7E-02 1.0E+00 1.5E-03 1.0E-02 2.5E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1009.9 1009.9 1.0E+00 1.7E-02 1.0E+00 1.0E-02 5.0E-02 9.0E-06 4.2E-01 3.8E-06

Debris Flows Unnamed Fan 1009.9 1009.93 1.0E+00 1.7E-02 1.0E+00 1.5E-03 1.0E-02 2.5E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1010.04 1010.08 1.0E+00 5.5E-03 1.0E+00 8.8E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1010.08 1010.09 1.0E+00 1.7E-02 1.0E+00 1.8E-02 1.0E-02 3.0E-06 1.8E-01 5.6E-07

Rock Slide Bombtram Mountain - 1010.09 1010.72 1.0E+00 5.0E-04 1.0E-02 1.0E-01 1.0E+00 5.0E-07 1.0E+00 5.0E-07 Coquihalla Valley

Debris Flows Unnamed Fan 1010.09 1010.11 1.0E+00 5.5E-03 1.0E+00 8.8E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1010.17 1010.18 1.0E+00 5.5E-03 1.0E+00 2.6E-05 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1010.18 1010.19 1.0E+00 5.5E-03 1.0E+00 1.7E-03 5.0E-02 4.7E-07 1.3E-01 <1.0E-7

Debris Flows Unnamed Fan 1010.19 1010.24 1.0E+00 5.5E-03 1.0E+00 2.6E-05 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1010.25 1010.26 1.0E+00 5.5E-03 1.0E+00 7.2E-15 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1010.26 1010.27 1.0E+00 5.5E-03 1.0E+00 1.9E-02 5.0E-02 5.1E-06 5.0E-01 2.6E-06

Debris Flows Unnamed Fan 1010.27 1010.31 1.0E+00 5.5E-03 1.0E+00 7.2E-15 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Rock Avalanches Bombtram Mountain 1010.33 1011.33 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 6.8E-06 1.0E+00 6.8E-06 3 - Coquihalla Valley

Debris Flows Unnamed Channel 1010.37 1010.38 1.0E+00 5.5E-03 1.0E+00 2.0E-02 1.0E-02 1.1E-06 2.0E-01 2.1E-07

Earth Landslide Bombtram Mountain 1010.46 1010.49 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 Slope Toe

Debris Flows Unnamed Fan 1010.68 1010.75 1.0E+00 1.7E-02 1.0E+00 7.1E-03 1.0E-02 1.2E-06 1.0E-02 <1.0E-7

Page 40 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Slide Bombtram Mountain - 1010.72 1011.26 1.0E+00 4.2E-04 1.0E-02 1.0E-01 1.0E+00 4.2E-07 1.0E+00 4.2E-07 Coquihalla Valley

Debris Flows Unnamed Channel 1010.75 1010.75 1.0E+00 1.7E-02 1.0E+00 6.5E-04 1.0E-02 1.1E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1010.75 1010.78 1.0E+00 1.7E-02 1.0E+00 7.1E-03 1.0E-02 1.2E-06 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1010.8 1010.81 1.0E+00 1.7E-02 1.0E+00 2.1E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1010.83 1010.84 1.0E+00 1.7E-02 1.0E+00 4.5E-02 5.0E-02 3.9E-05 8.3E-02 3.2E-06

Scour (Local) Unnamed Channel 1010.83 1010.84 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 1010.84 1010.86 1.0E+00 1.7E-02 1.0E+00 2.1E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1010.95 1010.95 1.0E+00 1.7E-02 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 1010.95 1010.96 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Unnamed Channel 1011.04 1011.05 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1011.04 1011.05 1.0E+00 1.7E-02 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1011.14 1011.15 1.0E+00 1.7E-02 1.0E+00 8.0E-02 5.0E-02 6.9E-05 8.2E-02 5.7E-06

Scour (Local) Unnamed Channel 1011.18 1011.18 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1011.18 1011.19 1.0E+00 1.7E-02 1.0E+00 5.7E-04 1.0E-02 <1.0E-7 3.7E-02 <1.0E-7

Rock Slide Coquihalla Valley 1011.26 1011.72 1.0E+00 3.6E-04 1.0E-02 1.0E-01 1.0E+00 3.6E-07 1.0E+00 3.6E-07 South - Coquihalla Valley

Scour (Local) Unnamed Channel 1011.28 1011.29 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-04 9.5E-07 8.0E-01 7.6E-07

Debris Flows Unnamed Channel 1011.28 1011.29 1.0E+00 5.5E-02 1.0E+00 6.5E-04 5.0E-02 1.8E-06 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1011.29 1011.3 1.0E+00 1.7E-02 1.0E+00 2.1E-04 1.0E-02 <1.0E-7 9.0E-01 <1.0E-7

Rock Avalanches Bombtram Mountain 1011.33 1012.35 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 7.0E-06 1.0E+00 7.0E-06 4 - Coquihalla Valley

Scour (Local) Unnamed Channel 1011.48 1011.49 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Fan 1011.48 1011.48 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1011.48 1011.49 1.0E+00 5.5E-03 1.0E+00 6.5E-04 1.0E-02 <1.0E-7 2.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1011.49 1011.49 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1011.56 1011.58 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Scour (Local) Unnamed Channel 1011.58 1011.58 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1011.58 1011.58 1.0E+00 5.5E-03 1.0E+00 3.8E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1011.58 1011.59 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1011.67 1011.69 1.0E+00 5.5E-03 1.0E+00 4.7E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Page 41 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Unnamed Channel 1011.69 1011.71 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1011.69 1011.71 1.0E+00 1.7E-02 1.0E+00 8.0E-02 5.0E-02 6.9E-05 8.8E-02 6.1E-06

Debris Flows Unnamed Fan 1011.71 1011.71 1.0E+00 5.5E-03 1.0E+00 4.7E-04 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Rock Slide Coquihalla Valley 1011.72 1012.25 1.0E+00 4.3E-04 1.0E-02 1.0E-01 1.0E+00 4.3E-07 1.0E+00 4.3E-07 South - Coquihalla Valley

Debris Flows Unnamed Channel 1011.79 1011.79 1.0E+00 5.5E-03 1.0E+00 4.8E-04 1.0E-02 <1.0E-7 5.8E-02 <1.0E-7

Debris Flows Unnamed Channel 1011.95 1011.98 1.0E+00 1.7E-02 1.0E+00 4.3E-04 1.0E-02 <1.0E-7 1.5E-02 <1.0E-7

Scour (Local) Unnamed Channel 1011.96 1011.97 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-04 2.0E-07 1.0E+00 2.0E-07

Debris Flows Unnamed Fan 1011.98 1012.04 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1012.04 1012.05 1.0E+00 5.5E-03 1.0E+00 2.0E-02 5.0E-02 5.5E-06 4.9E-01 2.7E-06

Scour (Local) Unnamed Channel 1012.15 1012.16 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1012.15 1012.16 1.0E+00 1.7E-02 1.0E+00 6.5E-03 5.0E-02 5.6E-06 2.2E-01 1.3E-06

Debris Flows Unnamed Fan 1012.16 1012.17 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1012.21 1012.26 1.0E+00 5.5E-03 1.0E+00 1.3E-02 5.0E-02 3.5E-06 1.0E-02 <1.0E-7

Rock Slide Coquihalla Valley 1012.25 1012.61 1.0E+00 2.8E-04 1.0E-02 1.0E-01 1.0E+00 2.8E-07 1.0E+00 2.8E-07 South - Coquihalla Valley

Debris Flows Unnamed Fan 1012.26 1012.41 1.0E+00 5.5E-03 1.0E+00 1.3E-02 5.0E-02 3.5E-06 1.0E-02 <1.0E-7

Rock Avalanches Old Coquihalla Road - 1012.34 1013.94 1.0E+00 4.0E-05 5.0E-01 5.0E-01 1.0E+00 1.1E-05 1.0E+00 1.1E-05 Coquihalla Valley

Scour (Local) Unnamed Channel 1012.41 1012.43 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1012.41 1012.43 1.0E+00 1.7E-02 1.0E+00 2.4E-03 5.0E-02 2.0E-06 7.7E-01 1.6E-06

Debris Flows Unnamed Fan 1012.43 1012.44 1.0E+00 5.5E-03 1.0E+00 1.3E-02 5.0E-02 3.5E-06 1.0E-02 <1.0E-7

Debris Slides Old Coquihalla Road - 1012.46 1015.48 1.0E+00 1.0E+00 1.0E-01 1.0E+00 1.0E-03 1.0E-04 6.0E-02 6.0E-06 Coquihalla Valley

Debris Flows Unnamed Fan 1012.57 1012.61 1.0E+00 1.7E-03 1.0E+00 2.0E-02 5.0E-02 1.7E-06 1.0E-02 <1.0E-7

Rock Slide Coquihalla Valley 1012.61 1013.16 1.0E+00 4.2E-04 1.0E-01 1.0E-01 1.0E+00 4.2E-06 1.0E+00 4.2E-06 South - Coquihalla Valley

Debris Flows Unnamed Channel 1012.61 1012.62 1.0E+00 1.7E-02 1.0E+00 7.7E-03 5.0E-02 6.7E-06 1.7E-01 1.1E-06

Debris Flows Unnamed Fan 1012.62 1012.76 1.0E+00 1.7E-03 1.0E+00 2.0E-02 5.0E-02 1.7E-06 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1012.76 1012.77 1.0E+00 1.7E-02 1.0E+00 4.5E-02 1.0E-02 7.8E-06 2.0E-01 1.6E-06

Scour (Local) Unnamed Channel 1012.77 1012.77 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 6.0E-01 1.1E-07

Debris Flows Unnamed Fan 1012.77 1012.82 1.0E+00 1.7E-03 1.0E+00 2.0E-02 5.0E-02 1.7E-06 1.0E-02 <1.0E-7

Page 42 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Unnamed Channel 1013 1013.01 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 6.0E-01 1.1E-07

Debris Flows Unnamed Channel 1013 1013.01 1.0E+00 5.5E-03 1.0E+00 1.2E-02 5.0E-02 3.2E-06 1.9E-01 6.3E-07

Debris Flows Unnamed Channel 1013.15 1013.17 1.0E+00 1.7E-03 1.0E+00 4.5E-02 5.0E-02 3.9E-06 2.3E-01 8.9E-07

Rock Slide Old Coquihalla Road - 1013.16 1013.6 1.0E+00 3.6E-04 1.0E-02 1.0E-01 1.0E+00 3.6E-07 7.0E-01 2.5E-07 Coquihalla Road

Rockfall Old Coquihalla Road 1013.16 1013.94 1.0E+00 1.0E-02 5.0E-02 5.0E-01 1.0E+00 2.5E-04 6.0E-02 1.5E-05 West Slopes - Coquihalla Valley

Debris Flows Unnamed Channel 1013.21 1013.23 1.0E+00 5.5E-03 1.0E+00 4.5E-02 5.0E-02 1.2E-05 2.0E-01 2.4E-06

Rock Slide Old Coquihalla Road - 1013.6 1013.94 1.0E+00 2.7E-04 1.0E-02 1.0E-01 1.0E+00 2.7E-07 7.0E-01 1.9E-07 Coquihalla Road

Earth Landslide Old Coquihalla Road 1013.9 1015.02 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-02 1.0E-06 6.0E-01 6.0E-07 West Slope

Debris Slides Ladner Creek North 1015.75 1017.44 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-03 1.0E-07 6.0E-01 <1.0E-7 Slopes

Lateral Erosion Shylock Creek 1015.98 1016 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-03 4.9E-06 6.0E-01 2.9E-06 (Bank Erosion)

Debris Flows Shylock Creek 1 1015.98 1016 1.0E+00 5.5E-03 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 5.4E-01 <1.0E-7

Scour (Local) Shylock Creek 1015.98 1016 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-03 2.5E-06 6.0E-01 1.5E-06

Debris Flows Shylock Creek 2 1016.23 1016.23 1.0E+00 5.5E-03 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 5.4E-01 <1.0E-7

Scour (Local) Unnamed Channel 1016.23 1016.23 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 6.0E-01 1.5E-07

Debris Flows Shylock Creek 3 1016.58 1016.59 1.0E+00 1.7E-02 1.0E+00 9.8E-03 2.5E-02 4.2E-06 3.6E-01 1.5E-06

Debris Flows Shylock Creek 1016.81 1016.83 1.0E+00 5.5E-03 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 6.0E-01 <1.0E-7

Rock Avalanches Ladner Creek Slopes - 1016.82 1019.96 1.0E+00 9.0E-05 5.0E-01 5.0E-01 1.0E+00 2.1E-05 9.5E-01 2.0E-05 Coquihalla Valley

Lateral Erosion Coquihalla River 1016.84 1016.89 1.0E+00 5.0E-03 1.0E+00 1.0E+00 6.0E-03 2.1E-05 7.0E-02 2.1E-06 (Encroachment)

Outburst Floods Cascade Mountains - 1017.33 1017.63 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Ladner Creek and headwaters

Debris Floods Ladner Creek 1017.41 1017.43 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 4.8E-01 <1.0E-7

Scour (Local) Ladner Creek 1017.41 1017.43 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-03 5.0E-06 4.8E-01 2.4E-06

Lateral Erosion Ladner Creek 1017.41 1017.43 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-03 1.0E-05 4.8E-01 4.8E-06 (Bank Erosion)

Scour (Local) Carolin Creek 1018.25 1018.25 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1018.25 1018.26 1.0E+00 5.5E-03 1.0E+00 5.7E-02 5.0E-02 1.6E-05 1.9E-01 3.0E-06

Lateral Erosion Coquihalla River 1018.54 1018.59 1.0E+00 5.0E-03 1.0E+00 1.0E+00 6.0E-03 2.1E-05 7.0E-02 2.1E-06 (Encroachment)

Page 43 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Coquihalla River 1018.87 1018.94 1.0E+00 2.5E-03 1.0E+00 1.0E+00 6.0E-03 1.5E-05 8.0E-01 1.2E-05

Lateral Erosion Coquihalla River 1018.87 1018.94 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 8.0E-02 2.4E-06 (Bank Erosion)

Avulsion Coquihalla River 1018.87 1018.94 1.0E+00 1.5E-03 1.0E+00 2.5E-03 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Scour (Flooding) Dewdney Creek 1019.96 1020.06 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Floods Dewdney Creek Fan 1019.96 1020.01 1.0E+00 5.5E-03 1.0E+00 3.6E-02 5.0E-03 9.9E-07 3.6E-01 3.6E-07

Debris Floods Dewdney Creek 1020.01 1020.05 1.0E+00 5.5E-03 1.0E+00 1.0E-02 1.0E-04 <1.0E-7 9.0E-01 <1.0E-7

Scour (Local) Dewdney Creek 1020.01 1020.05 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-04 2.5E-06 4.8E-01 1.2E-06

Lateral Erosion Dewdney Creek 1020.01 1020.05 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-04 2.5E-06 4.8E-01 1.2E-06 (Bank Erosion)

Avulsion Dewdney Creek 1020.01 1020.05 1.0E+00 5.6E-04 1.0E+00 5.0E-03 5.0E-04 <1.0E-7 6.0E-01 <1.0E-7

Debris Floods Dewdney Creek Fan 1020.05 1020.05 1.0E+00 5.5E-03 1.0E+00 3.6E-02 5.0E-03 9.9E-07 3.6E-01 3.6E-07

Rock Avalanches Mount Snider North - 1020.92 1023.63 1.0E+00 7.0E-05 5.0E-01 5.0E-01 1.0E+00 1.8E-05 9.5E-01 1.7E-05 Coquihalla Valley

Earth Landslide Mount Snider - 1021.48 1022.59 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-01 1.0E-04 1.2E-01 1.2E-05 Coquihalla Valley

Scour (Local) Karen Creek 1021.61 1021.61 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-05 2.5E-07 6.0E-01 1.5E-07

Debris Floods Unnamed Channel 1022.38 1022.4 1.0E+00 1.7E-03 1.0E+00 2.3E-01 2.5E-02 9.7E-06 6.0E-01 5.8E-06

Earth Landslide Coquihalla River East 1022.43 1022.48 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-02 1.0E-06 6.0E-01 6.0E-07 Slope

Debris Floods Unnamed Channel 1022.49 1022.5 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 6.0E-01 <1.0E-7

Debris Floods Mount Snider Fan 1022.5 1022.59 1.0E+00 1.7E-03 1.0E+00 7.3E-03 5.0E-03 <1.0E-7 7.5E-02 <1.0E-7

Debris Floods Mount Snider Creek 1022.59 1022.59 1.0E+00 1.7E-03 1.0E+00 2.0E-02 5.0E-03 1.7E-07 2.5E-01 <1.0E-7

Debris Floods Mount Snider Fan 1022.59 1022.88 1.0E+00 1.7E-03 1.0E+00 7.3E-03 5.0E-03 <1.0E-7 7.5E-02 <1.0E-7

Scour (Local) Unnamed Channel 1022.59 1022.59 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Rock Slide Mount Snider - 1022.83 1023.04 1.0E+00 1.7E-04 1.0E-01 1.0E-01 1.0E+00 1.7E-06 7.0E-01 1.2E-06 Coquihalla Valley

Scour (Flooding) Coquihalla River 1022.89 1022.91 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Rockfall Mount Snider - 1022.91 1023.04 1.0E+00 1.0E-02 5.0E-02 5.0E-01 1.0E+00 2.5E-04 6.0E-02 1.5E-05 Coquihalla Valley

Rock Slide Mount Snider - 1023.04 1023.18 1.0E+00 1.1E-04 1.0E-01 1.0E-01 1.0E+00 1.1E-06 7.0E-01 7.8E-07 Coquihalla Valley

Rockfall Mount Snider - 1023.04 1023.22 1.0E+00 1.0E-03 5.0E-02 1.0E-01 1.0E+00 5.0E-06 6.0E-01 3.0E-06 Coquihalla Valley

Rock Slide Mount Snider - 1023.18 1023.53 1.0E+00 2.8E-04 1.0E-02 1.0E-01 1.0E+00 2.8E-07 7.0E-01 1.9E-07 Coquihalla Valley

Page 44 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rockfall Mount Snider - 1023.35 1023.48 1.0E+00 1.0E-03 5.0E-02 5.0E-01 1.0E+00 2.5E-05 3.0E-02 7.5E-07 Coquihalla Valley

Scour (Flooding) Coquihalla River 1023.4 1024.11 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Coquihalla River 1023.62 1023.69 1.0E+00 2.0E-03 1.0E+00 1.0E+00 6.0E-03 1.2E-05 8.0E-01 9.6E-06

Lateral Erosion Coquihalla River 1023.62 1023.69 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 8.0E-02 2.4E-06 (Bank Erosion)

Avulsion Coquihalla River 1023.62 1023.69 1.0E+00 2.3E-01 1.0E+00 2.0E-03 6.0E-03 2.7E-06 1.0E+00 2.7E-06

Rock Avalanches Mount Snider South - 1023.63 1024.39 1.0E+00 2.0E-05 5.0E-01 5.0E-01 1.0E+00 5.3E-06 1.0E+00 5.3E-06 Coquihalla Valley

Debris Slides Coquihalla River West 1024 1024.39 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 6.0E-01 <1.0E-7 Slopes 1

Rock Slide Emacipation 1024.13 1024.65 1.0E+00 4.2E-04 1.0E-01 1.0E-01 1.0E+00 4.2E-06 7.0E-01 2.9E-06 Mountain - Coquihalla Valley

Scour (Flooding) Coquihalla River 1024.32 1024.39 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Rock Avalanches Emancipation 1024.39 1026.71 1.0E+00 6.0E-05 1.0E+00 1.0E+00 1.0E+00 6.2E-05 9.5E-01 5.9E-05 Mountain - Coquihalla Valley

Rockfall Emancipation 1024.39 1025.47 1.0E+00 1.0E-03 1.0E-02 5.0E-01 1.0E+00 5.0E-06 6.0E-01 3.0E-06 Mountain - Coquihalla Valley

Debris Slides Coquihalla River West 1024.39 1025.47 1.0E+00 1.0E-01 1.0E-03 1.0E+00 1.0E-03 1.0E-07 6.0E-01 <1.0E-7 Slopes 2

Debris Flows Unnamed Fan 1024.45 1024.53 1.0E+00 1.7E-02 1.0E+00 6.7E-03 5.0E-02 5.8E-06 2.2E-01 1.2E-06

Debris Flows Unnamed Channel 1024.53 1024.53 1.0E+00 1.7E-02 1.0E+00 2.0E-02 5.0E-02 1.7E-05 2.7E-01 4.7E-06

Debris Flows Unnamed Fan 1024.53 1024.76 1.0E+00 1.7E-02 1.0E+00 6.7E-03 5.0E-02 5.8E-06 2.2E-01 1.2E-06

Rock Slide Emacipation 1024.65 1025.28 1.0E+00 4.8E-04 1.0E-01 1.0E-01 1.0E+00 4.8E-06 7.0E-01 3.3E-06 Mountain - Coquihalla Valley

Scour (Flooding) Coquihalla River 1025.51 1026.03 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Coquihalla River 1025.82 1025.9 1.0E+00 2.5E-03 1.0E+00 1.0E+00 2.0E-02 5.0E-05 8.0E-01 4.0E-05

Lateral Erosion Coquihalla River 1025.82 1025.9 1.0E+00 4.9E-03 1.0E+00 1.0E+00 2.0E-02 9.8E-05 8.0E-02 7.8E-06 (Bank Erosion)

Debris Floods Unnamed Fan 1026.03 1026.18 1.0E+00 5.5E-03 1.0E+00 2.7E-02 5.0E-03 7.5E-07 1.8E-01 1.3E-07

Scour (Local) Unnamed Channel 1026.18 1026.18 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Debris Floods Unnamed Channel 1026.18 1026.18 1.0E+00 5.5E-03 1.0E+00 9.1E-02 1.0E-04 <1.0E-7 2.9E-01 <1.0E-7

Debris Floods Unnamed Fan 1026.18 1026.24 1.0E+00 5.5E-03 1.0E+00 2.7E-02 5.0E-03 7.5E-07 1.8E-01 1.3E-07

Rock Slide East Tunnel Entrance 1026.49 1026.55 1.0E+00 5.0E-05 1.0E-01 1.0E-01 1.0E+00 4.7E-07 7.0E-01 3.3E-07 Mount Jarvis - Coquihalla Valley Page 45 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rockfall East Tunnel Entrance - 1026.49 1026.55 1.0E+00 1.0E-02 1.0E-02 5.0E-01 1.0E+00 5.0E-05 3.0E-02 1.5E-06 Mount Jarvis

Rock Slide Mount Jarvis - 1026.66 1027.12 1.0E+00 3.6E-04 1.0E+00 1.0E-01 1.0E+00 3.6E-05 4.9E-01 1.8E-05 Coquihalla Valley

Rockfall Mount Jarvis Talus 1026.66 1027.32 1.0E+00 1.0E-02 1.0E-02 5.0E-01 1.0E+00 5.0E-05 3.0E-02 1.5E-06 Slopes

Rock Avalanches Mount Jarvis 2 - 1026.71 1028.17 1.0E+00 4.0E-05 1.0E+00 1.0E+00 1.0E+00 4.0E-05 9.5E-01 3.8E-05 Coquihalla Valley

Rock Slide Mount Jarvis - 1027.12 1027.41 1.0E+00 2.3E-04 1.0E+00 1.0E-01 1.0E+00 2.3E-05 4.9E-01 1.1E-05 Coquihalla Valley

Rock Slide Mount Jarvis - 1027.41 1027.56 1.0E+00 1.2E-04 1.0E-02 1.0E-01 1.0E+00 1.2E-07 7.0E-01 <1.0E-7 Coquihalla Valley

Debris Flows Unnamed Fan 1027.54 1027.64 1.0E+00 5.5E-03 1.0E+00 1.2E-02 5.0E-02 3.3E-06 2.6E-01 8.4E-07

Debris Flows Unnamed Channel 1027.64 1027.66 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 6.0E-01 <1.0E-7

Debris Flows Unnamed Fan 1027.66 1027.68 1.0E+00 5.5E-03 1.0E+00 1.2E-02 5.0E-02 3.3E-06 2.6E-01 8.4E-07

Debris Flows Unnamed Channel 1027.68 1027.68 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 6.0E-01 <1.0E-7

Debris Flows Unnamed Fan 1027.68 1027.87 1.0E+00 5.5E-03 1.0E+00 1.2E-02 5.0E-02 3.3E-06 2.6E-01 8.4E-07

Rock Slide Mount Jarvis - 1027.87 1028.17 1.0E+00 2.3E-04 1.0E+00 1.0E-01 1.0E+00 2.3E-05 4.9E-01 1.1E-05 Coquihalla Valley

Debris Flows Unnamed Fan 1027.87 1027.94 1.0E+00 1.7E-02 1.0E+00 1.6E-02 1.0E-02 2.8E-06 5.2E-02 1.4E-07

Debris Flows Unnamed Channel 1027.94 1027.94 1.0E+00 1.7E-02 1.0E+00 2.0E-03 2.0E-03 <1.0E-7 4.8E-01 <1.0E-7

Debris Flows Unnamed Fan 1027.94 1028.03 1.0E+00 1.7E-02 1.0E+00 1.6E-02 1.0E-02 2.8E-06 5.2E-02 1.4E-07

Debris Flows Unnamed Fan 1028.04 1028.1 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1028.1 1028.11 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 1.0E-02 <1.0E-7

Debris Flows Unnamed Fan 1028.11 1028.13 1.0E+00 5.5E-03 1.0E+00 4.4E-03 1.0E-02 2.4E-07 1.0E-02 <1.0E-7

Rock Avalanches Mount Jarvis 3 - 1028.17 1030.66 1.0E+00 7.0E-05 5.0E-01 5.0E-01 1.0E+00 1.7E-05 9.5E-01 1.6E-05 Coquihalla Valley

Rock Slide Mount Jarvis - 1028.17 1028.38 1.0E+00 1.7E-04 1.0E+00 1.0E-01 1.0E+00 1.7E-05 4.9E-01 8.2E-06 Coquihalla Valley

Rock Slide Mount Jarvis - 1028.38 1028.68 1.0E+00 2.4E-04 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 7.0E-01 <1.0E-7 Coquihalla Valley

Debris Flows Unnamed Fan 1028.61 1028.64 1.0E+00 5.5E-03 1.0E+00 7.0E-04 1.0E-02 <1.0E-7 4.5E-02 <1.0E-7

Scour (Local) Unnamed Channel 1028.64 1028.65 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1028.64 1028.65 1.0E+00 5.5E-03 1.0E+00 2.0E-03 5.0E-02 5.5E-07 3.6E-01 2.0E-07

Debris Flows Unnamed Fan 1028.65 1028.73 1.0E+00 5.5E-03 1.0E+00 7.0E-04 1.0E-02 <1.0E-7 4.5E-02 <1.0E-7

Page 46 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Slide Mount Jarvis - 1028.69 1029.25 1.0E+00 4.5E-04 1.0E+00 1.0E-01 1.0E+00 4.5E-05 4.9E-01 2.2E-05 Coquihalla Valley

Rock Slide Mount Jarvis - 1029.25 1029.69 1.0E+00 3.5E-04 1.0E+00 1.0E-01 1.0E+00 3.5E-05 4.9E-01 1.7E-05 Coquihalla Valley

Rock Slide Mount Jarvis - 1029.69 1029.82 1.0E+00 1.0E-04 1.0E-02 1.0E-01 1.0E+00 1.0E-07 7.0E-01 <1.0E-7 Coquihalla Valley

Scour (Local) Coquihalla River 1029.79 1029.92 1.0E+00 5.0E-03 1.0E+00 1.0E+00 5.0E-03 2.5E-05 4.8E-01 1.2E-05

Lateral Erosion Coquihalla River 1029.79 1029.92 1.0E+00 1.0E-02 1.0E+00 1.0E+00 5.0E-03 5.0E-05 4.8E-02 2.4E-06 (Bank Erosion)

Avulsion Coquihalla River 1029.79 1029.92 1.0E+00 2.3E-02 1.0E+00 5.0E-03 5.0E-03 5.6E-07 6.0E-01 3.4E-07

Scour (Flooding) Coquihalla River 1029.84 1030 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Debris Flows Unnamed Fan 1030.35 1030.45 1.0E+00 1.7E-02 1.0E+00 2.8E-05 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1030.45 1030.47 1.0E+00 1.7E-02 1.0E+00 4.4E-02 2.5E-02 1.9E-05 3.6E-01 6.8E-06

Scour (Local) Railway Creek 1030.46 1030.47 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Debris Flows Unnamed Fan 1030.47 1030.56 1.0E+00 1.7E-02 1.0E+00 2.8E-05 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Rock Avalanches Mount Jarvis 4 - 1030.66 1032.5 1.0E+00 5.0E-05 5.0E-01 5.0E-01 1.0E+00 1.3E-05 9.5E-01 1.2E-05 Coquihalla Valley

Debris Flows Unnamed Fan 1031.43 1031.51 1.0E+00 5.5E-03 1.0E+00 1.8E-02 1.0E-02 1.0E-06 6.0E-01 6.1E-07

Debris Flows Unnamed Fan 1031.59 1031.87 1.0E+00 5.5E-03 1.0E+00 1.3E-02 1.0E-02 7.2E-07 6.0E-01 4.3E-07

Debris Slides Othello Road West 1032.39 1032.59 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-02 1.0E-06 6.0E-01 6.0E-07 Slope

Debris Slides Othello Road North 1033.1 1035.46 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 6.0E-01 <1.0E-7 Slope

Rockfall Ogilvie Peak - Othello 1033.98 1034.78 1.0E+00 1.0E-02 1.0E-02 5.0E-01 1.0E+00 5.0E-05 6.0E-02 3.0E-06

Rock Slide Ogilvie Peak - Othello 1034.05 1034.6 1.0E+00 4.4E-04 1.0E-02 1.0E-01 1.0E+00 4.4E-07 7.0E-01 3.1E-07

Rock Avalanches Ogilvie Peak - Othello 1035.46 1036.82 1.0E+00 4.0E-05 5.0E-01 5.0E-01 1.0E+00 9.2E-06 1.0E+00 9.2E-06

Rock Avalanches Hope Mountain - Hope 1039.3 1040.73 1.0E+00 4.0E-05 1.0E-01 5.0E-01 1.0E+00 1.9E-06 1.0E+00 1.9E-06

Scour (Flooding) Coquihalla River 1040.12 1040.54 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Coquihalla River 1040.13 1040.47 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-02 3.3E-05 8.0E-01 2.6E-05

Avulsion Coquihalla River 1040.13 1040.47 1.0E+00 2.0E-02 1.0E+00 1.0E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Coquihalla River 1040.13 1040.47 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-02 4.9E-05 8.0E-02 3.9E-06 (Bank Erosion)

Rock Avalanches Hope Mountain - Hope 1040.73 1043.11 1.0E+00 7.0E-05 5.0E-01 5.0E-01 1.0E+00 1.7E-05 1.0E+00 1.7E-05

Debris Flows Hope Mountain Fan 1041.46 1041.64 1.0E+00 5.5E-03 1.0E+00 3.6E-02 5.0E-02 1.0E-05 9.4E-01 9.4E-06

Page 47 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Hope Mountain 1041.64 1041.64 1.0E+00 5.5E-03 1.0E+00 2.5E-02 1.0E-02 1.4E-06 1.0E+00 1.4E-06 Channel 1

Debris Flows Hope Mountain Fan 1041.64 1041.65 1.0E+00 5.5E-03 1.0E+00 3.6E-02 5.0E-02 1.0E-05 9.4E-01 9.4E-06

Debris Flows Hope Mountain 1041.65 1041.68 1.0E+00 5.5E-02 1.0E+00 3.9E-02 2.0E-02 4.2E-05 1.8E-01 7.8E-06 Channel 2

Debris Flows Hope Mountain Fan 1041.68 1041.8 1.0E+00 5.5E-03 1.0E+00 3.6E-02 5.0E-02 1.0E-05 9.4E-01 9.4E-06

Debris Flows Hope (Charles) (Ryan) 1041.8 1041.85 1.0E+00 5.5E-02 1.0E+00 9.5E-02 1.0E-01 5.2E-04 7.5E-02 3.9E-05 Creek

Debris Flows Hope Mountain Fan 1041.85 1042.04 1.0E+00 5.5E-03 1.0E+00 3.6E-02 5.0E-02 1.0E-05 9.4E-01 9.4E-06

Rock Avalanches Hope Mountain - Hope 1043.11 1044.21 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 7.6E-06 1.0E+00 7.6E-06

Outburst Floods Cascade Mountains - 1044.12 1045.12 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Silver Creek and lake and headwaters

Scour (Local) Silverhope Creek 1044.33 1044.4 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Lateral Erosion Silverhope Creek 1044.33 1044.4 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 2.4E-01 7.1E-06 (Bank Erosion)

Avulsion Silverhope Creek 1044.33 1044.4 1.0E+00 8.4E-03 1.0E+00 1.9E-03 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Rock Avalanches South Slope 1 - Floods 1045.62 1048.46 1.0E+00 4.0E-05 5.0E-01 5.0E-01 1.0E+00 1.0E-05 1.0E+00 1.0E-05

Rock Avalanches South Slope 2 - Floods 1048.46 1048.53 1.0E+00 0.0E+00 1.0E+00 1.0E+00 1.0E+00 1.0E-06 1.0E+00 1.0E-06

Debris Slides Chawuthen Creek 1048.46 1048.53 1.0E+00 1.0E-03 1.0E-03 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 Slopes

Scour (Local) Chawuthen Creek 1048.58 1048.62 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Avulsion Chawuthen Creek 1048.58 1048.62 1.0E+00 6.0E-05 1.0E+00 2.0E-03 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Lateral Erosion Chawuthen Creek 1048.58 1048.62 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7 (Bank Erosion)

Debris Floods Chawuthen Creek 1048.58 1048.62 1.0E+00 1.7E-03 1.0E+00 0.0E+00 5.0E-03 <1.0E-7 9.0E-01 <1.0E-7

Debris Flows Unnamed Channel 1049.67 1049.68 1.0E+00 5.5E-03 1.0E+00 6.5E-03 5.0E-02 1.8E-06 1.0E+00 1.8E-06

Rock Avalanches South Slope - Ruby 1049.74 1051.45 1.0E+00 3.0E-05 1.0E+00 1.0E+00 1.0E+00 2.5E-05 1.0E+00 2.5E-05 Creek

Debris Slides Two Fan Slopes 1049.76 1051.41 1.0E+00 1.0E-03 1.0E-03 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Two Fan Creek 1 Fan 1049.79 1050.03 1.0E+00 5.5E-03 1.0E+00 7.8E-03 5.0E-02 2.1E-06 6.3E-01 1.3E-06

Rock Slide East Slope - Floods 1049.84 1050.45 1.0E+00 4.8E-04 1.0E-02 1.0E-01 1.0E+00 4.8E-07 1.0E+00 4.8E-07

Debris Flows Two Fan Creek Channel 1050.03 1050.05 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 1.0E+00 1.1E-07

Debris Flows Two Fan Creek 1 Fan 1050.05 1050.13 1.0E+00 5.5E-03 1.0E+00 7.8E-03 5.0E-02 2.1E-06 6.3E-01 1.3E-06

Debris Flows Two Fan Creek 1 1050.13 1050.14 1.0E+00 5.5E-02 1.0E+00 4.2E-02 5.0E-02 1.2E-04 8.0E-02 9.3E-06

Page 48 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Local) Unnamed Channel 1050.13 1050.15 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Two Fan Creek 2 Fan 1050.14 1050.26 1.0E+00 5.5E-02 1.0E+00 8.9E-03 5.0E-02 2.4E-05 4.1E-01 9.9E-06

Debris Flows Two Fan Creek 2 1050.26 1050.29 1.0E+00 5.5E-02 1.0E+00 2.0E-02 5.0E-02 5.5E-05 5.9E-02 3.3E-06

Scour (Local) Unnamed Channel 1050.26 1050.29 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Two Fan Creek 2 Fan 1050.29 1050.47 1.0E+00 5.5E-02 1.0E+00 8.9E-03 5.0E-02 2.4E-05 4.1E-01 9.9E-06

Debris Flows Unnamed Fan 1050.47 1050.49 1.0E+00 1.7E-02 1.0E+00 1.2E-02 1.0E-02 2.1E-06 2.8E-01 5.9E-07

Debris Flows Unnamed Channel 1050.49 1050.49 1.0E+00 1.7E-02 1.0E+00 5.6E-03 1.0E-02 9.7E-07 1.0E+00 9.7E-07

Debris Flows Unnamed Fan 1050.49 1050.57 1.0E+00 1.7E-03 1.0E+00 1.2E-02 1.0E-02 2.1E-07 1.0E+00 2.1E-07

Debris Flows Unnamed Channel 1050.57 1050.58 1.0E+00 1.7E-03 1.0E+00 5.3E-02 5.0E-02 4.6E-06 1.0E+00 4.6E-06

Debris Flows Unnamed Fan 1050.58 1050.68 1.0E+00 1.7E-03 1.0E+00 1.2E-02 1.0E-02 2.1E-07 1.0E+00 2.1E-07

Debris Flows Unnamed Fan 1050.82 1050.9 1.0E+00 1.7E-02 1.0E+00 4.9E-03 1.0E-02 8.4E-07 1.0E+00 8.4E-07

Debris Flows Unnamed Fan 1050.9 1051.05 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Debris Flows Unnamed Channel 1051.05 1051.05 1.0E+00 5.5E-03 1.0E+00 1.2E-02 1.0E-02 6.7E-07 1.0E+00 6.7E-07

Debris Flows Unnamed Fan 1051.05 1051.18 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Scour (Local) Unnamed Channel 1051.18 1051.18 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1051.29 1051.29 1.0E+00 5.5E-03 1.0E+00 2.0E-02 2.5E-02 2.7E-06 1.0E+00 2.7E-06

Debris Flows Unnamed Fan 1051.29 1051.36 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Rock Avalanches Hunter Creek Slopes - 1051.54 1052.59 1.0E+00 1.0E-05 1.0E+00 1.0E+00 1.0E+00 1.5E-05 1.0E+00 1.5E-05 Ruby Creek

Debris Slides Hunter Creek Road 1051.98 1052.59 1.0E+00 1.0E-03 1.0E-03 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7 Slopes

Debris Flows Unnamed Channel 1052.23 1052.24 1.0E+00 1.7E-03 1.0E+00 2.0E-03 5.0E-02 1.7E-07 1.0E+00 1.7E-07

Rock Avalanches Ruby Creek Slopes - 1052.59 1054.15 1.0E+00 2.0E-05 1.0E+00 1.0E+00 1.0E+00 2.3E-05 1.0E+00 2.3E-05 Ruby Creek

Scour (Local) Hunter Creek 1052.62 1052.66 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-04 5.0E-07 6.4E-01 3.2E-07

Lateral Erosion Hunter Creek 1052.62 1052.66 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 6.4E-01 3.1E-07 (Bank Erosion)

Rockfall Mount Devoy - Ruby 1053.35 1055.51 1.0E+00 1.0E-02 1.0E-04 5.0E-01 1.0E+00 5.0E-07 1.0E+00 5.0E-07 Creek

Debris Slides Mt. Devoy Slopes 1053.35 1053.65 1.0E+00 1.0E-03 1.0E-02 1.0E+00 1.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Rock Slide Mount Devoy - Ruby 1053.35 1053.65 1.0E+00 2.4E-04 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 1.0E+00 <1.0E-7 Creek

Rock Avalanches Mount Devoy North 1054.15 1056.16 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 7.3E-06 1.0E+00 7.3E-06 Slope - Laidlaw

Page 49 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Avalanches Mount Devoy South 1056.16 1059.15 1.0E+00 4.0E-05 1.0E-01 5.0E-01 1.0E+00 2.2E-06 1.0E+00 2.2E-06 Slope - Laidlaw

Outburst Floods Cascade Mountains - 1057.51 1059.51 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.0E+00 1.0E-05 Wahleach Creek and lake and dam

Debris Floods Lorenzetta Creek Fan 1058.06 1058.07 1.0E+00 1.7E-03 1.0E+00 3.8E-02 2.5E-02 1.6E-06 1.0E+00 1.6E-06

Debris Floods Lorenzetta Creek 1058.07 1058.12 1.0E+00 1.7E-03 1.0E+00 1.0E-02 5.0E-03 <1.0E-7 9.0E-01 <1.0E-7

Scour (Local) Lorenzetta Creek 1058.07 1058.12 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Lorenzetta Creek 1058.07 1058.12 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Debris Floods Lorenzetta Creek Fan 1058.12 1058.64 1.0E+00 1.7E-03 1.0E+00 3.8E-02 2.5E-02 1.6E-06 1.0E+00 1.6E-06

Scour (Local) Wahleach/Jones Creek 1058.64 1058.79 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 8.0E-01 9.1E-06

Avulsion Wahleach/Jones Creek 1058.64 1058.79 1.0E+00 1.5E-03 1.0E+00 1.9E-03 6.0E-03 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Wahleach/Jones Creek 1058.64 1058.79 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 4.0E-01 1.2E-05 (Bank Erosion)

Debris Floods Lorenzetta Creek Fan 1058.64 1058.71 1.0E+00 1.7E-03 1.0E+00 3.8E-02 2.5E-02 1.6E-06 1.5E-01 2.4E-07

Debris Floods Lorenzetta Creek 1058.71 1058.74 1.0E+00 5.5E-03 1.0E+00 3.3E-02 5.0E-03 8.9E-07 1.0E-02 <1.0E-7 Channel 1

Debris Floods Lorenzetta Creek Fan 1058.74 1058.79 1.0E+00 1.7E-03 1.0E+00 3.8E-02 2.5E-02 1.6E-06 1.5E-01 2.4E-07

Debris Floods Lorenzetta Creek Fan 1058.79 1058.84 1.0E+00 1.7E-03 1.0E+00 3.8E-02 2.5E-02 1.6E-06 1.0E+00 1.6E-06

Rock Avalanches Unnamed Slope 1 - 1059.15 1062.3 1.0E+00 5.0E-05 1.0E+00 1.0E+00 1.0E+00 4.6E-05 1.0E+00 4.6E-05 Laidlaw

Debris Slides Fraser Valley East 1059.41 1078.01 1.0E+00 1.0E+00 1.0E-02 1.0E+00 1.0E-03 1.0E-05 1.0E+00 1.0E-05 Slopes

Debris Flows Unnamed Channel 1059.76 1059.77 1.0E+00 1.7E-02 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Channel 1059.84 1059.84 1.0E+00 1.7E-02 1.0E+00 0.0E+00 0.0E+00 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 1060.45 1060.5 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-02 1.8E-06 4.5E-01 8.0E-07

Rock Slide East Slope 1 - Laidlaw 1060.49 1061.6 1.0E+00 8.8E-04 1.0E-01 1.0E-01 1.0E+00 8.8E-06 1.0E+00 8.8E-06

Debris Flows Unnamed Channel 1060.5 1060.51 1.0E+00 1.7E-02 1.0E+00 4.5E-03 5.0E-02 3.9E-06 1.0E+00 3.9E-06

Debris Flows Unnamed Fan 1060.51 1060.55 1.0E+00 1.7E-02 1.0E+00 1.0E-02 1.0E-02 1.8E-06 4.5E-01 8.0E-07

Debris Flows Unnamed Fan 1060.57 1060.81 1.0E+00 5.5E-03 1.0E+00 1.4E-02 1.0E-02 7.8E-07 5.4E-01 4.2E-07

Debris Flows Unnamed Fan 1060.81 1060.82 1.0E+00 5.5E-03 1.0E+00 1.4E-02 1.0E-02 7.8E-07 5.4E-01 4.2E-07

Debris Flows Unnamed Channel 1060.82 1060.82 1.0E+00 5.5E-03 1.0E+00 2.0E-02 1.0E-02 1.1E-06 1.0E+00 1.1E-06

Debris Flows Unnamed Fan 1060.82 1061 1.0E+00 5.5E-03 1.0E+00 1.4E-02 1.0E-02 7.8E-07 5.4E-01 4.2E-07

Page 50 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Fan 1061 1061.13 1.0E+00 1.7E-02 1.0E+00 1.1E-02 5.0E-02 9.8E-06 7.0E-01 6.8E-06

Debris Flows Unnamed Channel 1061.13 1061.15 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.7E-01 8.5E-06

Debris Flows Unnamed Fan 1061.15 1061.23 1.0E+00 1.7E-02 1.0E+00 1.1E-02 5.0E-02 9.8E-06 7.0E-01 6.8E-06

Debris Flows Unnamed Channel 1061.23 1061.23 1.0E+00 1.7E-02 1.0E+00 2.1E-02 1.0E-02 3.7E-06 1.0E+00 3.7E-06

Debris Flows Unnamed Fan 1061.23 1061.37 1.0E+00 1.7E-02 1.0E+00 1.1E-02 5.0E-02 9.8E-06 7.0E-01 6.8E-06

Debris Flows Unnamed Fan 1061.37 1061.59 1.0E+00 5.5E-03 1.0E+00 5.1E-04 1.0E-02 <1.0E-7 6.0E-02 <1.0E-7

Rock Slide East Slope 2 - Laidlaw 1061.6 1061.94 1.0E+00 2.7E-04 1.0E-01 1.0E-01 1.0E+00 2.7E-06 1.0E+00 2.7E-06

Debris Flows Unnamed Fan 1062.09 1062.09 1.0E+00 1.7E-02 1.0E+00 1.5E-09 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Unnamed Channel 1062.09 1062.11 1.0E+00 1.7E-02 1.0E+00 5.6E-02 5.0E-02 4.8E-05 8.2E-02 4.0E-06

Debris Flows Unnamed Fan 1062.11 1062.13 1.0E+00 1.7E-02 1.0E+00 1.5E-09 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Rock Slide East Slope 3 - Laidlaw 1062.25 1062.45 1.0E+00 1.6E-04 1.0E-03 1.0E-01 1.0E+00 <1.0E-7 1.0E+00 <1.0E-7

Rock Avalanches Unnamed Slope 2 - 1062.3 1064.12 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 6.6E-06 1.0E+00 6.6E-06 Laidlaw

Debris Flows Unnamed Fan 1062.37 1062.38 1.0E+00 5.5E-03 1.0E+00 8.0E-03 5.0E-02 2.2E-06 6.3E-01 1.4E-06

Debris Flows Unnamed Channel 1062.38 1062.38 1.0E+00 5.5E-03 1.0E+00 2.0E-03 1.0E-02 1.1E-07 1.0E+00 1.1E-07

Debris Flows Philips Creek Fan 1062.38 1062.56 1.0E+00 5.5E-03 1.0E+00 8.0E-03 5.0E-02 2.2E-06 6.3E-01 1.4E-06

Debris Flows Philips Creek Channel 1062.56 1062.58 1.0E+00 5.5E-03 1.0E+00 6.9E-02 5.0E-02 1.9E-05 1.4E-01 2.5E-06

Debris Flows Philips Creek Fan 1062.58 1063.21 1.0E+00 5.5E-03 1.0E+00 8.0E-03 5.0E-02 2.2E-06 6.3E-01 1.4E-06

Debris Flows Philips Creek 3 1063.21 1063.22 1.0E+00 1.7E-02 1.0E+00 2.0E-03 1.0E-02 3.5E-07 1.0E+00 3.5E-07

Debris Flows Philips Creek Fan 1063.22 1063.31 1.0E+00 5.5E-03 1.0E+00 8.0E-03 5.0E-02 2.2E-06 6.3E-01 1.4E-06

Debris Flows Philips Creek Fan 1063.31 1063.4 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-02 2.9E-06 6.8E-01 2.0E-06

Debris Flows Philips Creek 1 1063.4 1063.4 1.0E+00 5.5E-02 1.0E+00 3.4E-04 5.0E-02 9.3E-07 3.7E-01 3.5E-07

Debris Flows Philips Creek Fan 1063.4 1063.54 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-02 2.9E-06 6.8E-01 2.0E-06

Scour (Local) Phillips Creek 1063.4 1063.4 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Philips Creek 2 1063.54 1063.55 1.0E+00 5.5E-02 1.0E+00 3.0E-03 5.0E-02 8.3E-06 6.2E-01 5.1E-06

Scour (Local) Unnamed Channel 1063.54 1063.55 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Philips Creek Fan 1063.55 1063.57 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-02 2.9E-06 6.8E-01 2.0E-06

Debris Flows Philips Creek Fan 1063.57 1063.74 1.0E+00 5.5E-03 1.0E+00 1.0E-02 5.0E-02 2.9E-06 6.8E-01 2.0E-06

Debris Flows Philips Creek Fan 1063.74 1063.8 1.0E+00 5.5E-03 1.0E+00 6.6E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Debris Flows Philips Creek 4 1063.8 1063.81 1.0E+00 5.5E-03 1.0E+00 3.6E-03 5.0E-02 1.0E-06 1.0E+00 1.0E-06

Page 51 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Philips Creek Fan 1063.81 1063.92 1.0E+00 5.5E-03 1.0E+00 6.6E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Debris Flows Philips Creek 5 1063.92 1063.94 1.0E+00 1.7E-02 1.0E+00 2.1E-03 5.0E-02 1.8E-06 1.0E+00 1.8E-06

Debris Flows Philips Creek Fan 1063.94 1064.09 1.0E+00 5.5E-03 1.0E+00 6.6E-03 5.0E-02 1.8E-06 1.0E+00 1.8E-06

Debris Flows Philips Creek 6 1064.09 1064.09 1.0E+00 5.5E-03 1.0E+00 1.5E-03 5.0E-02 4.0E-07 1.0E+00 4.0E-07

Debris Flows Philips Creek Fan 1064.09 1064.14 1.0E+00 5.5E-03 1.0E+00 6.6E-03 5.0E-02 1.8E-06 1.0E+00 1.8E-06

Rockfall Mount Ludwig North 1065.9 1066.23 1.0E+00 1.0E-02 5.0E-02 5.0E-01 1.0E+00 2.5E-04 4.0E-02 1.0E-05 Slope - Cheam View

Rock Avalanches Mount Ludwig North - 1065.92 1066.69 1.0E+00 1.0E-05 5.0E-01 5.0E-01 1.0E+00 2.8E-06 1.0E+00 2.8E-06 Cheam View

Lateral Erosion Unnamed Channel 1065.96 1066.19 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 8.0E-01 3.9E-07 (Bank Erosion)

Scour (Local) Unnamed Channel 1065.96 1066.19 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 8.0E-01 1.5E-07

Avulsion Unnamed Channel 1065.96 1066.19 1.0E+00 4.5E-04 1.0E+00 1.9E-03 1.0E-04 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Mount Ludwig Fan 1065.98 1066.04 1.0E+00 5.5E-03 1.0E+00 1.6E-02 1.0E-02 9.0E-07 7.2E-02 <1.0E-7

Debris Flows Mount Ludwig 1066.04 1066.06 1.0E+00 5.5E-03 1.0E+00 7.0E-03 5.0E-02 1.9E-06 2.8E-01 5.3E-07 Channel

Debris Flows Mount Ludwig Fan 1066.06 1066.17 1.0E+00 5.5E-03 1.0E+00 1.6E-02 1.0E-02 9.0E-07 7.2E-02 <1.0E-7

Debris Flows John Creek 1066.17 1066.19 1.0E+00 1.7E-02 1.0E+00 1.5E-02 5.0E-02 1.3E-05 1.1E-01 1.4E-06

Debris Flows John Creek Fan 1066.17 1066.17 1.0E+00 1.7E-02 1.0E+00 1.3E-02 5.0E-02 1.1E-05 1.7E-01 2.0E-06

Debris Flows Herrling Creek Fan 1066.19 1066.23 1.0E+00 1.7E-02 1.0E+00 1.3E-02 5.0E-02 1.1E-05 1.7E-01 2.0E-06

Debris Flows Herrling Creek Fan 1066.23 1066.52 1.0E+00 1.7E-02 1.0E+00 1.3E-02 5.0E-02 1.1E-05 7.3E-01 8.3E-06

Debris Flows Herrling Creek 1066.52 1066.55 1.0E+00 5.5E-02 1.0E+00 4.5E-02 1.0E-02 2.5E-05 3.3E-01 8.2E-06

Scour (Local) Herrling Creek 1066.54 1066.54 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-04 9.5E-07 1.0E+00 9.5E-07

Debris Flows Herrling Creek Fan 1066.55 1066.74 1.0E+00 1.7E-02 1.0E+00 1.3E-02 5.0E-02 1.1E-05 7.3E-01 8.3E-06

Rock Avalanches Mount Ludwig South - 1066.69 1068.34 1.0E+00 2.0E-05 5.0E-01 5.0E-01 1.0E+00 6.0E-06 1.0E+00 6.0E-06 Cheam View

Rockfall Mount Ludwig South 1066.77 1067.65 1.0E+00 1.0E-01 1.0E-02 5.0E-01 1.0E+00 5.0E-04 4.0E-02 2.0E-05 Slope - Cheam View

Debris Flows Unnamed Fan 1067.71 1067.84 1.0E+00 5.5E-02 1.0E+00 1.0E-02 5.0E-02 2.8E-05 2.0E-01 5.8E-06

Debris Floods Unnamed Channel 1067.84 1067.87 1.0E+00 5.5E-02 1.0E+00 1.0E-01 5.0E-03 2.7E-05 2.5E-01 6.8E-06

Debris Flows Unnamed Fan 1067.87 1067.95 1.0E+00 5.5E-02 1.0E+00 1.0E-02 5.0E-02 2.8E-05 2.0E-01 5.8E-06

Debris Flows Unnamed Channel 1067.95 1067.97 1.0E+00 5.5E-02 1.0E+00 1.1E-02 5.0E-02 3.0E-05 1.1E-01 3.3E-06

Scour (Local) Unnamed Channel 1067.96 1067.96 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Unnamed Fan 1067.97 1068.09 1.0E+00 5.5E-02 1.0E+00 1.0E-02 5.0E-02 2.8E-05 2.0E-01 5.8E-06

Page 52 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Unnamed Fan 1068.09 1068.25 1.0E+00 1.7E-02 1.0E+00 7.4E-03 1.0E-02 1.3E-06 3.6E-01 4.7E-07

Debris Flows Ted Creek Fan 1068.25 1068.32 1.0E+00 1.7E-02 1.0E+00 9.3E-03 5.0E-02 8.1E-06 6.6E-01 5.3E-06

Debris Flows Ted Creek 1068.32 1068.36 1.0E+00 5.5E-02 1.0E+00 1.5E-02 5.0E-02 4.1E-05 2.2E-01 9.0E-06

Scour (Local) Unnamed Channel 1068.32 1068.36 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-04 1.9E-07 1.0E+00 1.9E-07

Lateral Erosion Unnamed Channel 1068.32 1068.36 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-04 4.9E-07 1.0E+00 4.9E-07 (Bank Erosion)

Rock Avalanches Wahleach Slope - 1068.34 1070.7 1.0E+00 3.0E-05 5.0E-01 5.0E-01 1.0E+00 8.6E-06 1.0E+00 8.6E-06 Cheam View

Debris Flows Ted Creek Fan 1068.36 1068.83 1.0E+00 1.7E-02 1.0E+00 9.3E-03 5.0E-02 8.1E-06 6.6E-01 5.3E-06

Debris Flows Concrete Flume Fan 1068.83 1069.19 1.0E+00 1.7E-02 1.0E+00 8.1E-03 5.0E-02 7.0E-06 6.3E-01 4.5E-06

Debris Flows Concrete Flume 1069.19 1069.2 1.0E+00 1.7E-02 1.0E+00 3.5E-02 1.0E-02 6.0E-06 1.0E+00 6.0E-06 Channel 1

Debris Flows Concrete Flume Fan 1069.2 1069.28 1.0E+00 1.7E-02 1.0E+00 8.1E-03 5.0E-02 7.0E-06 6.3E-01 4.5E-06

Scour (Local) Unnamed Channel 1069.27 1069.3 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-03 1.9E-06 8.0E-01 1.5E-06

Lateral Erosion Unnamed Channel 1069.27 1069.3 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-03 4.9E-06 8.0E-01 3.9E-06 (Bank Erosion)

Debris Flows Concrete Flume Creek 1069.28 1069.3 1.0E+00 5.5E-02 1.0E+00 4.7E-02 5.0E-02 1.3E-04 7.3E-02 9.4E-06

Debris Flows Concrete Flume Fan 1069.3 1069.46 1.0E+00 1.7E-02 1.0E+00 8.1E-03 5.0E-02 7.0E-06 6.3E-01 4.5E-06

Debris Flows Concrete Flume 1069.46 1069.49 1.0E+00 1.7E-03 1.0E+00 4.2E-02 5.0E-02 3.7E-06 1.0E+00 3.7E-06 Channel 2

Debris Flows Concrete Flume Fan 1069.49 1069.52 1.0E+00 1.7E-02 1.0E+00 8.1E-03 5.0E-02 7.0E-06 6.3E-01 4.5E-06

Debris Flows Patterson Creek Fan 1069.52 1069.54 1.0E+00 5.5E-02 1.0E+00 1.5E-02 1.0E-02 8.3E-06 5.6E-01 4.6E-06

Debris Flows Triple Gate Creek 1069.54 1069.55 1.0E+00 5.5E-02 1.0E+00 6.5E-03 1.0E-02 3.6E-06 1.0E-02 <1.0E-7

Scour (Local) Unnamed Channel 1069.54 1069.55 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Patterson Creek Fan 1069.55 1069.69 1.0E+00 5.5E-02 1.0E+00 1.5E-02 1.0E-02 8.3E-06 5.6E-01 4.6E-06

Debris Flows Patterson Creek 1069.69 1069.7 1.0E+00 5.5E-02 1.0E+00 6.5E-03 1.0E-02 3.6E-06 1.0E+00 3.6E-06 Channel 1

Debris Flows Patterson Creek Fan 1069.7 1069.79 1.0E+00 5.5E-02 1.0E+00 1.5E-02 1.0E-02 8.3E-06 5.6E-01 4.6E-06

Scour (Local) Unnamed Channel 1069.77 1069.83 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-04 9.5E-07 8.0E-01 7.6E-07

Debris Flows Patterson Creek 1069.79 1069.81 1.0E+00 5.5E-02 1.0E+00 2.0E-02 5.0E-02 5.4E-05 1.1E-01 5.7E-06

Debris Flows Patterson Creek Fan 1069.81 1069.84 1.0E+00 5.5E-02 1.0E+00 1.5E-02 1.0E-02 8.3E-06 5.6E-01 4.6E-06

Debris Flows Transformer Creek Fan 1069.86 1070.07 1.0E+00 1.7E-02 1.0E+00 1.4E-02 5.0E-02 1.2E-05 7.4E-01 8.7E-06

Debris Flows Transformer Creek 1070.07 1070.07 1.0E+00 1.7E-02 1.0E+00 1.2E-02 5.0E-02 1.1E-05 7.8E-01 8.2E-06

Page 53 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Transformer Creek Fan 1070.07 1070.19 1.0E+00 1.7E-02 1.0E+00 1.4E-02 5.0E-02 1.2E-05 7.4E-01 8.7E-06

Debris Flows Transformer Creek 1070.19 1070.2 1.0E+00 5.5E-02 1.0E+00 2.0E-02 1.0E-02 1.1E-05 4.7E-01 5.1E-06 Channel 1

Debris Flows Transformer Creek Fan 1070.2 1070.27 1.0E+00 1.7E-02 1.0E+00 1.4E-02 5.0E-02 1.2E-05 7.4E-01 8.7E-06

Debris Flows Transformer Creek 1070.27 1070.28 1.0E+00 1.7E-02 1.0E+00 7.7E-03 5.0E-02 6.6E-06 1.0E+00 6.6E-06 Channel 2

Debris Flows Transformer Creek Fan 1070.28 1070.28 1.0E+00 1.7E-02 1.0E+00 1.4E-02 5.0E-02 1.2E-05 7.4E-01 8.7E-06

Debris Flows Concrete Wall Fan 1070.28 1070.38 1.0E+00 5.5E-03 1.0E+00 6.7E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Debris Flows Concrete Wall Channel 1070.38 1070.39 1.0E+00 5.5E-03 1.0E+00 2.0E-02 1.0E-02 1.1E-06 1.0E+00 1.1E-06 1

Debris Flows Concrete Wall Fan 1070.39 1070.51 1.0E+00 5.5E-03 1.0E+00 6.7E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Debris Flows Concrete Wall Channel 1070.51 1070.52 1.0E+00 1.7E-02 1.0E+00 6.5E-03 1.0E-02 1.1E-06 1.0E+00 1.1E-06 2

Debris Flows Concrete Wall Fan 1070.52 1070.57 1.0E+00 5.5E-03 1.0E+00 6.7E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Rock Slide Cheam Peak - Cheam 1070.56 1071.34 1.0E+00 6.2E-04 1.0E-02 1.0E-01 1.0E+00 6.2E-07 1.0E+00 6.2E-07 View

Debris Flows Concrete Wall Creek 1070.57 1070.58 1.0E+00 1.7E-02 1.0E+00 2.4E-02 1.0E-02 4.1E-06 1.0E+00 4.1E-06

Debris Flows Concrete Wall Fan 1070.58 1070.68 1.0E+00 5.5E-03 1.0E+00 6.7E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Debris Flows Concrete Wall Channel 1070.68 1070.7 1.0E+00 5.5E-02 1.0E+00 5.8E-03 5.0E-02 1.6E-05 5.7E-01 9.0E-06 3

Rock Avalanches Cheam Peak North - 1070.7 1072.49 1.0E+00 3.0E-05 1.0E+00 1.0E+00 1.0E+00 2.6E-05 1.0E+00 2.6E-05 Bridal Falls

Debris Flows Concrete Wall Fan 1070.7 1070.7 1.0E+00 5.5E-03 1.0E+00 6.7E-03 5.0E-02 1.8E-06 6.0E-01 1.1E-06

Lateral Erosion Unnamed Channel 1071.18 1071.23 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Unnamed Channel 1071.18 1071.23 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Cheam Creek Fan 1071.18 1071.22 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek Channel 1071.22 1071.23 1.0E+00 5.5E-02 1.0E+00 5.3E-03 5.0E-02 1.5E-05 1.8E-01 2.7E-06 1

Debris Flows Cheam Creek Fan 1071.23 1071.43 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek Channel 1071.43 1071.43 1.0E+00 1.7E-03 1.0E+00 4.2E-03 5.0E-02 3.6E-07 1.5E-01 <1.0E-7 2

Debris Flows Cheam Creek Fan 1071.43 1071.53 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek Channel 1071.53 1071.54 1.0E+00 1.7E-03 1.0E+00 1.9E-02 1.0E-02 3.3E-07 2.0E-01 <1.0E-7 3

Debris Flows Cheam Creek Fan 1071.54 1071.62 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Page 54 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Flows Cheam Creek Channel 1071.62 1071.63 1.0E+00 5.5E-03 1.0E+00 1.4E-03 5.0E-02 3.7E-07 1.5E-01 <1.0E-7 4

Debris Flows Cheam Creek Fan 1071.63 1071.74 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek 1 1071.74 1071.76 1.0E+00 5.5E-02 1.0E+00 2.0E-02 1.0E-02 1.1E-05 1.4E-01 1.5E-06

Scour (Local) Unnamed Channel 1071.75 1071.75 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Debris Flows Cheam Creek Fan 1071.76 1071.83 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek Channel 1071.83 1071.83 1.0E+00 5.5E-03 1.0E+00 6.5E-03 1.0E-02 3.6E-07 1.6E-02 <1.0E-7 5

Debris Flows Cheam Creek Fan 1071.83 1072.01 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek Channel 1072.01 1072.02 1.0E+00 1.7E-02 1.0E+00 1.5E-02 5.0E-02 1.3E-05 1.6E-01 2.1E-06 6

Debris Flows Cheam Creek Fan 1072.02 1072.15 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Debris Flows Cheam Creek Channel 1072.15 1072.16 1.0E+00 5.5E-03 1.0E+00 3.5E-02 5.0E-02 9.6E-06 2.7E-01 2.6E-06 7

Debris Flows Cheam Creek Fan 1072.16 1073 1.0E+00 1.7E-02 1.0E+00 2.7E-02 5.0E-02 2.3E-05 3.8E-01 9.0E-06

Rock Avalanches Cheam Peak South - 1072.49 1075.13 1.0E+00 4.0E-05 1.0E+00 1.0E+00 1.0E+00 3.9E-05 1.0E+00 3.9E-05 Bridal Falls

Scour (Local) Unnamed Channel 1072.99 1072.99 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Floods Unnamed Channel 1073 1073.02 1.0E+00 5.5E-02 1.0E+00 1.0E-02 2.5E-02 1.4E-05 7.0E-01 9.5E-06

Debris Flows Unnamed Fan 1073.05 1073.15 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Debris Flows Unnamed Channel 1 1073.15 1073.15 1.0E+00 5.5E-03 1.0E+00 1.1E-03 5.0E-02 3.1E-07 1.0E+00 3.1E-07

Debris Flows Unnamed Fan 1073.15 1073.45 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Debris Flows Unnamed Channel 2 1073.45 1073.46 1.0E+00 5.5E-03 1.0E+00 2.0E-02 1.0E-02 1.1E-06 1.0E+00 1.1E-06

Debris Flows Unnamed Fan 1073.46 1073.69 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Debris Flows Unnamed Fan 1073.69 1073.7 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Scour (Local) Popkum Creek 1073.7 1073.7 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Unnamed Fan 1073.7 1074.07 1.0E+00 5.5E-03 1.0E+00 2.9E-02 5.0E-02 7.9E-06 8.9E-01 7.1E-06

Debris Floods Unnamed Channel 1074.75 1074.76 1.0E+00 1.7E-02 1.0E+00 1.8E-02 2.5E-02 8.0E-06 1.0E+00 8.0E-06

Debris Floods Anderson Creek Fan 1074.87 1075.23 1.0E+00 1.7E-03 1.0E+00 8.1E-02 2.5E-02 3.5E-06 7.7E-01 2.7E-06

Rock Avalanches Mount Archibald 1075.13 1077.45 1.0E+00 3.0E-05 5.0E-01 1.0E-01 1.0E+00 1.6E-06 1.0E+00 1.6E-06 Centre Slope - Bridal Falls

Debris Floods Anderson Creek 1075.23 1075.23 1.0E+00 5.5E-02 1.0E+00 1.0E-02 5.0E-03 2.7E-06 1.0E+00 2.7E-06

Scour (Local) Anderson Creek 1075.23 1075.23 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 55 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Debris Floods Anderson Creek Fan 1075.23 1075.53 1.0E+00 1.7E-03 1.0E+00 8.1E-02 2.5E-02 3.5E-06 7.7E-01 2.7E-06

Debris Flows Bridal Falls Channel 1075.53 1075.54 1.0E+00 1.7E-02 1.0E+00 6.5E-03 1.0E-02 1.1E-06 1.0E+00 1.1E-06

Debris Flows Bridal Falls Fan 1075.54 1075.8 1.0E+00 1.7E-02 1.0E+00 7.4E-04 1.0E-02 1.3E-07 7.8E-02 <1.0E-7

Debris Flows Bridal Creek Fan 1076.1 1076.33 1.0E+00 1.7E-03 1.0E+00 9.2E-03 5.0E-02 7.9E-07 6.6E-01 5.2E-07

Debris Flows Bridal Creek 0 1076.5 1076.51 1.0E+00 1.7E-02 1.0E+00 7.3E-03 5.0E-03 6.3E-07 6.2E-02 <1.0E-7

Scour (Local) Bridal Creek 1076.5 1076.51 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Bridal Creek Fan 1076.51 1076.75 1.0E+00 1.7E-03 1.0E+00 9.2E-03 5.0E-02 7.9E-07 6.6E-01 5.2E-07

Debris Flows Bridal Creek 1 1076.75 1076.76 1.0E+00 5.5E-02 1.0E+00 1.5E-02 2.0E-02 1.7E-05 7.9E-02 1.3E-06

Scour (Local) Bridal Creek 1076.76 1076.76 1.0E+00 1.9E-03 1.0E+00 1.0E+00 5.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Debris Flows Bridal Creek Fan 1076.76 1076.97 1.0E+00 1.7E-03 1.0E+00 9.2E-03 5.0E-02 7.9E-07 6.6E-01 5.2E-07

Rockfall Bridal Falls - Popkum 1076.97 1077.53 1.0E+00 1.0E-02 1.0E-02 5.0E-01 1.0E+00 5.0E-05 2.0E-02 1.0E-06

Rock Slide Mount Archibald - 1076.97 1077.61 1.0E+00 5.1E-04 1.0E+00 1.0E+00 1.0E+00 5.1E-04 5.0E-01 2.5E-04 Bridal Falls

Debris Flows Bridal Creek Fan 1076.97 1077 1.0E+00 1.7E-03 1.0E+00 9.2E-03 5.0E-02 7.9E-07 1.7E-01 1.4E-07

Debris Flows Bridal Creek 2 1077.02 1077.03 1.0E+00 1.7E-03 1.0E+00 6.2E-03 2.5E-02 2.7E-07 3.2E-01 <1.0E-7

Debris Flows Unnamed Channel 1077.25 1077.25 1.0E+00 5.5E-02 1.0E+00 1.1E-03 2.5E-02 1.5E-06 4.8E-01 7.2E-07

Rock Avalanches Mount Archibald 1077.45 1083.27 1.0E+00 8.0E-05 1.0E-02 5.0E-01 1.0E+00 4.2E-07 1.0E+00 4.2E-07 South Slope - Bridal Falls

Debris Flows Golf Course Fan 1077.45 1077.53 1.0E+00 5.5E-03 1.0E+00 1.1E-03 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Golf Course Fan 1077.53 1077.55 1.0E+00 5.5E-03 1.0E+00 1.1E-03 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Debris Flows Golf Course Channel 1 1077.55 1077.55 1.0E+00 5.5E-02 1.0E+00 2.0E-03 2.5E-02 2.7E-06 6.3E-01 1.7E-06

Debris Flows Golf Course Fan 1077.55 1077.61 1.0E+00 5.5E-03 1.0E+00 1.1E-03 1.0E-02 <1.0E-7 1.0E-02 <1.0E-7

Scour (Local) Nevin Creek 1080.63 1080.64 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Elk Creek 1084.89 1084.95 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Elk Creek 1084.89 1084.95 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Semmihault Creek 1090.23 1090.26 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Semmihault Creek 1090.23 1090.26 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Chilliwack Creek 1091.48 1091.51 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Lateral Erosion Chilliwack Creek 1091.48 1091.51 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7 (Bank Erosion)

Page 56 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Scour (Flooding) Vedder Crossing 1094.69 1094.86 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Lateral Erosion Chilliwack/Vedder 1100.14 1100.84 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-02 4.9E-05 1.0E-03 <1.0E-7 (Bank Erosion) River

Scour (Local) Chilliwack/Vedder 1100.14 1100.84 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-02 2.5E-05 1.0E-03 <1.0E-7 River

Avulsion Chilliwack/Vedder 1100.14 1100.84 1.0E+00 8.0E-05 1.0E+00 1.0E-04 1.0E-02 <1.0E-7 1.0E+00 <1.0E-7 River

Scour (Local) Peach Creek 1100.17 1100.18 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7

Avulsion Peach Creek 1100.17 1100.18 1.0E+00 2.0E-05 1.0E+00 1.0E-04 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Lateral Erosion Peach Creek 1100.17 1100.18 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 (Bank Erosion)

Scour (Flooding) Vedder River 1100.41 1101.34 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Chilliwack/Vedder 1100.49 1100.5 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 River Side Channel

Avulsion Chilliwack/Vedder 1100.49 1100.5 1.0E+00 2.0E-05 1.0E+00 1.0E-04 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7 River Side Channel

Lateral Erosion Chilliwack/Vedder 1100.49 1100.5 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 (Bank Erosion) River Side Channel

Scour (Local) Unnamed Channel 1100.74 1100.75 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-04 <1.0E-7

Lateral Erosion Unnamed Channel 1100.74 1100.75 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-04 <1.0E-7 (Bank Erosion)

Scour (Local) Street Creek 1101.26 1101.28 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Street Creek 1101.26 1101.28 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Stewart Slough 1104.1 1104.16 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Stewart Slough 1104.12 1104.14 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Stewart Slough 1104.12 1104.14 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Stewart Slough 1104.44 1105.45 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Sumas Lake Canal 1108.8 1108.85 1.0E+00 2.5E-03 1.0E+00 1.0E+00 6.0E-03 1.5E-05 1.0E-03 <1.0E-7

Lateral Erosion Sumas Lake Canal 1108.8 1108.85 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Scour (Flooding) Sumas River 1112.76 1112.86 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Sumas River 1112.76 1112.8 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-03 1.1E-05 1.0E-03 <1.0E-7

Lateral Erosion Sumas River 1112.76 1112.8 1.0E+00 4.9E-03 1.0E+00 1.0E+00 6.0E-03 2.9E-05 1.0E-03 <1.0E-7 (Bank Erosion)

Debris Slides Sumas Mountain 1115.2 1116.36 1.0E+00 1.0E+00 1.0E-02 1.0E+00 1.0E-03 1.0E-05 1.0E+00 1.0E-05 Slopes

Page 57 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Rock Slide South Slope - Kilgard 1115.22 1116.36 1.0E+00 7.0E-04 1.0E-02 1.0E-01 1.0E+00 7.0E-07 1.0E+00 7.0E-07

Debris Slides Ledgeview Creek 1116.96 1117.37 1.0E+00 1.0E+00 1.0E-03 1.0E+00 1.0E-03 1.0E-06 1.0E+00 1.0E-06 Slopes

Scour (Local) Trib. To Clayburn 1117.27 1117.28 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 Creek/ Ledgeview Creek

Earth Landslide Clayburn Heights 1118.32 1119.48 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 Slopes

Scour (Local) Unnamed Channel 1118.64 1118.66 1.0E+00 2.5E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Clayburn Creek 1120.9 1120.92 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Clayburn Creek 1120.9 1120.92 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Flooding) Clayburn Creek 1121.91 1121.95 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Clayburn Creek 1121.91 1121.93 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Lateral Erosion Clayburn Creek 1121.91 1121.93 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7 (Bank Erosion)

Scour (Flooding) McLennan Creek 1126.3 1126.34 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Mclennan Creek 1126.31 1126.32 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Mclennan Creek 1126.31 1126.32 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Earth Landslide Colingy Creek Slopes 1128.4 1128.5 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 8.0E-01 8.0E-06

Scour (Local) Coligny Creek 1128.43 1128.45 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Earth Landslide Starr Road Gullies - 1132.5 1132.93 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-02 1.0E-05 1.6E-01 1.6E-06 Abbotsford

Scour (Local) Unnamed Channel 1134.06 1134.06 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 1.0E+00 <1.0E-7

Scour (Local) Unnamed Channel 1134.99 1135 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Earth Landslide Nathan Creek 1135.8 1135.93 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 Tributary Slopes

Earth Landslide Nathan Creek 1135.93 1136.42 1.0E+00 1.0E-02 1.0E-02 1.0E+00 1.0E-02 1.0E-06 1.0E+00 1.0E-06 Approach Slopes - Langley

Earth Landslide Nathan Creek East 1136.42 1136.56 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-01 1.0E-05 Slope - Langley

Scour (Flooding) Nathan Creek 1136.56 1136.7 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Earth Landslide Nathan Creek 1136.56 1136.7 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-03 1.0E-06 1.0E+00 1.0E-06

Scour (Local) Nathan Creek 1136.61 1136.67 1.0E+00 2.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Avulsion Nathan Creek 1136.61 1136.67 1.0E+00 1.1E-04 1.0E+00 2.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Page 58 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Lateral Erosion Nathan Creek 1136.61 1136.67 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Earth Landslide Nathan Creek West 1136.7 1136.84 1.0E+00 1.0E-02 1.0E+00 1.0E+00 1.0E-02 1.0E-04 1.0E-01 1.0E-05 Slope - Langley

Earth Landslide 264 St Gully Slopes 1138.05 1138.65 1.0E+00 1.0E-02 1.0E-03 1.0E+00 1.0E-02 1.0E-07 1.0E+00 1.0E-07

Earth Landslide West Creek East 1141.27 1141.63 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 1.0E+00 1.0E-05 Approach

Scour (Flooding) West Creek 1141.62 1141.67 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Earth Landslide West Creek East 1141.63 1141.67 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.6E-01 1.6E-06 Slope - Langley

Scour (Local) West Creek 1141.64 1141.67 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Avulsion West Creek 1141.64 1141.67 1.0E+00 4.2E-03 1.0E+00 5.0E-03 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion West Creek 1141.64 1141.67 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Earth Landslide West Creek West 1141.67 1141.78 1.0E+00 1.0E-03 1.0E-01 1.0E+00 1.0E-01 1.0E-05 1.6E-01 1.6E-06 Slope - Langley

Earth Landslide Railway Slopes - Forest 1143.73 1144.56 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-02 1.0E-05 1.6E-01 1.6E-06 Knolls

Scour (Local) Davidson Creek 1144.31 1144.33 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Davidson Creek 1144.31 1144.33 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Earth Landslide Salmon River Tributary 1145.57 1145.74 1.0E+00 1.0E-03 1.0E+00 1.0E+00 1.0E-01 1.0E-04 8.0E-02 8.0E-06 Slopes - Forest Knolls

Scour (Local) Salmon River 1145.98 1146.07 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7

Lateral Erosion Salmon River 1145.98 1146.07 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 (Bank Erosion)

Scour (Flooding) Salmon River 1146 1146.07 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Earth Landslide Golf Slope - Fort 1149.06 1149.36 1.0E+00 1.0E-02 1.0E-01 1.0E+00 1.0E-02 1.0E-05 5.0E-01 5.0E-06 Langley

Scour (Flooding) Unnamed Channel 1151.59 1152.19 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Unnamed Channel 1152.35 1152.48 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Unnamed Channel 1152.58 1152.61 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Flooding) Fraser River Tributary 1153.5 1153.85 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07 31

Scour (Local) Unnamed Drainage 1157.98 1158.03 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-01 <1.0E-7

Scour (Flooding) Fraser River 1159.26 1162.36 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Earth Landslide SFPR - Fraser Heights 1163.67 1164.09 1.0E+00 1.0E-01 1.0E+00 1.0E+00 1.0E-02 1.0E-03 1.0E-03 1.0E-06

Page 59 of 60 Geohazard Pre-mitigated Post-mitigated

Category Location Name KP Start KP End I F S H S V V FLOC M FLOC

Earth Landslide SFPR - Fraser Heights 1164.09 1164.34 1.0E+00 1.0E-01 1.0E+00 1.0E+00 1.0E-01 1.0E-02 1.0E-03 1.0E-05

Earth Landslide SFPR - Fraser Heights 1164.34 1165.25 1.0E+00 1.0E-01 1.0E+00 1.0E+00 1.0E-02 1.0E-03 1.0E-03 1.0E-06

Scour (Local) Fraser River 1166.67 1167.86 1.0E+00 1.9E-03 1.0E+00 1.0E+00 6.0E-02 1.1E-04 1.0E-03 1.1E-07

Scour (Flooding) Fraser River 1166.68 1167.68 1.0E+00 5.0E-03 1.0E-01 1.0E+00 1.0E-03 5.0E-07 1.0E+00 5.0E-07

Scour (Local) Colony Farm 1167.82 1167.82 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 Watercourse B

Scour (Local) Colony Farm 1168.05 1168.07 1.0E+00 1.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 6.0E-04 <1.0E-7 Watercourse B

Scour (Local) Dawes Hill Creek 1169.31 1169.32 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Dawes Hill Creek 1169.31 1169.32 1.0E+00 4.9E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Como Creek 1171.18 1171.19 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Scour (Local) Nelson Creek 1172.21 1172.22 1.0E+00 3.3E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Nelson Creek 1172.21 1172.22 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion)

Scour (Local) Stoney Creek 1176.65 1176.65 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7

Lateral Erosion Stoney Creek 1176.65 1176.65 1.0E+00 5.0E-03 1.0E+00 1.0E+00 1.0E-05 <1.0E-7 8.0E-01 <1.0E-7 (Bank Erosion) 1569 Records

Page 60 of 60 Trans Mountain Pipeline ULC, Trans Mountain Expansion Project February 27, 2017 Quantitative Geohazard Frequency Assessment – Post Mitigation Project No.: 0095150-22

APPENDIX C LIST OF GEOHAZARDS BY GEOHAZARD TYPE

Trans Mountain Attachment 1 Condition 16 Final BGC ENGINEERING INC. Geohazard List By Hazard