Download - CAYOOSH CREEK WATERSHED - British Columbia · Cayoosh Creek Watershed 1 Watershed Risk Assessment 1. INTRODUCTION 1.1. PROJECT OVERVIEW This Watershed Risk Assessment (WRA) is funded

CAYOOSH CREEK WATERSHED

Risk Assessment

Prepared for: Ainsworth Engineered Canada LP

Lillooet Division

Submitted by: Integrated ProAction Corp.

1425 Hugh Allan Drive, Kamloops, BC V1S 1J3 Phone: 250-828-7977 Fax: 250-828-2183

Website: www.intpac.ca

March 30, 2007

EXECUTIVE SUMMARY This Watershed Risk Assessment is a Forest Investment Account (FIA) funded project to identify and complete a risk assessment for the non-status roads in the Cayoosh Creek Watershed. Ainsworth Engineered Canada LP is the lead licensee and responsible for the management of FIA funding in the Lillooet Timber Supply Area (TSA). This project followed the standards outlined in the FIA Activity Standards for Road Deactivation, Landslide and Gully Rehabilitation Projects Document (Version 5 – 2003/2004). The risk assessment was carried out in conjunction with an Access Management Plan for the Cayoosh Creek Watershed. The objective of this project is to complete a risk assessment for each non-status road within the project area. The results from this project will be used in the Access Management Plan to determine which non-status roads should be deactivated and which should receive environmental maintenance. The Cayoosh Creek watershed is located southwest of the district of Lillooet and covers an area of approximately 1165.3 km2. The project area includes: Cayoosh Creek, Enterprise Creek, Downton Creek, Boulder Creek, Gott Creek, Van Horlick Creek, Casper Creek, Blowdown Creek, Texas Creek, and Seton ridge. A partial risk analysis was completed for the non-status roads that were identified within the project area. Partial risk analysis involves determining the likelihood of occurrence of a landslide and that landslide being a hazard to and directly or indirectly reaching or otherwise affecting a specific value at risk. Risk, as it pertains to this project, relates to the likelihood of landslides resulting from forest development (roads) and surface erosion and sediment delivery to streams and was determined to be the product of the risk multiplied by the consequence. Of the 225 non-status roads or road sections identified in the project 13 are classified as very high risk, 29 are classified as high risk and the remaining 183 were classified as either moderate or low risk. This report provides a qualitative evaluation of potential landslide and erosion hazards associated with non-status roads in the project area, an estimate of the downslope/downstream landslide consequences, recommendations, and a prioritized list for future field assessments and remedial work. Field assessments were not possible due to the timing of the project. A field assessment of all the roads is required in snow-free conditions to confirm the risk ratings determined in this report.

Table of Contents

1. INTRODUCTION ...................................................................................................... 1 1.1. PROJECT OVERVIEW ............................................................................................ 1 1.2. TERMS OF REFERENCE ......................................................................................... 1

2. STUDY AREA DESCRIPTION ................................................................................ 1 2.1. CHARACTERISTICS OF THE CAYOOSH CREEK WATERSHED.................................. 1 2.2. NON-STATUS ROADS WITHIN THE CAYOOSH CREEK WATERSHED ...................... 1 2.3. NON-STATUS ROAD LINKAGES TO THE PUBLIC ROAD SYSTEM .......................... 2

3. WATERSHED RISK ASSESSMENT ....................................................................... 2 3.1. OBJECTIVES OF THE WATERSHED RISK ASSESSMENT .......................................... 2 3.2. RISK ASSESSMENT PROCEDURE ........................................................................... 2 3.3. RISK RATING DESCRIPTION ................................................................................. 3

3.3.1. Low Risk Roads........................................................................................... 3 3.3.2. Moderate Risk Roads .................................................................................. 4 3.3.3. High Risk Roads.......................................................................................... 4 3.3.4. Very High Risk Roads ................................................................................. 4

3.4. RISK RATING RESULTS ........................................................................................ 4 4. CONCLUSION........................................................................................................... 5 5. LIMITATIONS........................................................................................................... 7 6. REFERENCES ........................................................................................................... 8

List of Tables

Table 1: Risk Rating Matrix ............................................................................................... 3 Table 2: Number of roads within each risk rating in the Cayoosh Creek Watershed......... 5 Table 3: Road Assessment/Work Priority........................................................................... 5

List of Appendices

Appendix 1: General Location Map Appendix 2: Description of Road Risk Rating Criteria Appendix 3: Description of Road Consequence Rating Appendix 4: Risk Rating Summary Appendix 5: Risk Assessment Map

Cayoosh Creek Watershed 1 Watershed Risk Assessment

1. INTRODUCTION 1.1. PROJECT OVERVIEW

This Watershed Risk Assessment (WRA) is funded by the Forest Investment Account (FIA) Land-base Program, Restoration & Rehabilitation Component, Terrestrial Activity Area. Ainsworth Engineered Canada LP is the lead Licensee and responsible for the management of FIA funding in the Lillooet Timber Supply Area (TSA). The objective of this project is to complete a risk assessment for each non-status road within the Cayoosh Creek watershed in the Lillooet TSA which includes: Cayoosh Creek, Enterprise Creek, Downton Creek, Boulder Creek, Gott Creek, Van Horlick Creek, Casper Creek, Blowdown Creek, Texas Creek, and Seton Ridge (see Appendix 1 for an overview map of the project area). The results of this risk assessment will be used to identify and prioritize the non-status roads that should be deactivated or that should receive environmental maintenance through the FIA program.

1.2. TERMS OF REFERENCE The Watershed Risk Assessment was completed within the time frame and budget submitted to Ainsworth Engineered Canada LP by Integrated ProAction Corp. Furthermore, the WRA was drafted in accordance with both the 2003/2004 FIA standards for road deactivation, landslide and gully rehabilitation projects and the 2003/2004 FIA standards for environmental maintenance projects on non-status forest roads.

2. STUDY AREA DESCRIPTION

2.1. CHARACTERISTICS OF THE CAYOOSH CREEK WATERSHED The Cayoosh Creek Watershed is located east of the Coast Mountains and west of the Thompson-Okanagan Plateau, within the Fraser Plateau, Eastern South Coast Mountains, and Northern Thompson Plateau hydrologic zones. The watershed is located southwest of the district of Lillooet (see Appendix 1) and covers an area of approximately 1165.3 km2, 97.1 % of which is crown land. Private land accounts for 2%, (23.3 km2), and Indian Reserves account for the remaining 0.9% (10.5 km2) of the land within the project area. The elevation within the watershed ranges from approximately 200m at the boundary on the Fraser River to a maximum of approximately 2880m at the mountain peaks around Enterprise, Copper, and Downton Creeks. The regions streamflow is generated from lakes, overland flow (runoff) and snowmelt. The Cayoosh Creek watershed has eight Biogeoclimatic Ecosystem Classification (BEC) zones within its boundary: Coastal Western Hemlock (CWH), Mountain Hemlock (MH), Ponderosa Pine (PP), Interior Douglas Fir (IDF), Montane Spruce (MS), Engelmann Spruce-Subalpine Fir (ESSF), Interior Mountain-heather Alpine (IMA), and Coastal Mountain-heather Alpine (CMA).

2.2. NON-STATUS ROADS WITHIN THE CAYOOSH CREEK WATERSHED Several sources were used to determine the status of roads within the project area including consolidated FDP data, Land and Resource Data Warehouse (LRDW) road data, road data from Ainsworth, and Terrain Resource Inventory Mapping (TRIM). Of the


roads identified in the watershed, approximately 216 are currently not under permit and are classified as non-status roads.

2.3. NON-STATUS ROAD LINKAGES TO THE PUBLIC ROAD SYSTEM All of the roads within the project area directly or indirectly link to Highway 99, also known as the Duffey Lake road.

3. WATERSHED RISK ASSESSMENT

3.1. OBJECTIVES OF THE WATERSHED RISK ASSESSMENT The objective of this project is to complete a risk assessment for each non-status road within the project area. Risk, as it pertains to this project, relates to the likelihood of landslides resulting from forest development (roads) and surface erosion and sediment delivery to streams.

3.2. RISK ASSESSMENT PROCEDURE A partial risk analysis was completed for the non-status roads that were identified within the project area. Partial risk analysis involves determining the likelihood of occurrence of a landslide and that landslide being a hazard to and directly or indirectly reaching or otherwise affecting a specific value at risk. Partial risk analysis is not a measure of the expected degree of damage to a specific value (MoF 2003b).

Alternatively, specific risk analysis or total risk analysis may be more appropriate to conduct if the vulnerability or severity of human injury, or of an adverse effect to health, forest resources, property, or other non-forest resource values, must be determined to properly prioritize candidate projects. This involves partial risk analysis, together with estimates of the degree of harm or loss to a given value or set of values if the landslide does occur. In some cases, to make informed decisions, it may be necessary to also consider the value or cost of values at risk (MoF 2003b).

For the purposes of this project, which is to be used to identify and prioritize the non-status roads that should be deactivated or that should receive environmental maintenance, it was determined that the partial risk analysis was appropriate.

The risk assessment included:

• Collecting existing information (maps, photos, reports) and discussing the history of the area with Licensee and Government representatives.

• Incorporating current info (roads, streams, blocks, terrain, etc) onto an overview base map.

• Applying risk ratings to overview inventory base maps.

It should be noted that due to the timing of the project (January to March) there were no field assessments conducted. The risk ratings are based upon observations made from the detailed terrain stability mapping (DTSM), orthographic photos, topographic maps, local knowledge, and input from road users. A field assessment of the roads by a qualified registered professional is required to confirm the results of this assessment.


3.3. RISK RATING DESCRIPTION The risk rating for this project, summarized in Table 1, was determined to be the product of the risk multiplied by the consequence. The risk rating takes into account the probability of a slope failure on or around a non-status road; and where there is a probability of a slope failure occurrence, the consequence (environmental, social and economic) of the potential failure was considered. The highest priority sites are considered those that have both a high sediment yield and probability of sediment transport and a high probability that the sediment will reach streams or otherwise adversely affect fish habitat and drinking water quality and supply (MoF, 2003a).

Table 1: Risk Rating Matrix

Hazard Consequence

Low Moderate High

Low L L M

Moderate L M H

High M H VH

The road risk ratings for the Watershed Risk Assessment were assigned a hazard rating based on analysis of the detailed terrain stability mapping (DTSM) polygons located on or around the non-status roads. The DTSM data used in the project included a five-class slope stability designation, a five-class soil erosion potential rating, and a five-class risk of sediment delivery to streams rating (refer to Appendix 2). As per the Risk Assessment Procedure (MoF, 1993) the five slope stability classes were assigned hazard ratings. Class IV (potentially unstable) or V (unstable) terrain are considered a high hazard. The soil erosion potential and sediment delivery to streams classes were used to determine the potential sediment input on streams. The consequence ratings were assessed by determining the potential impact of an event on the various downslope/downstream values, in accordance with the Risk Assessment Procedure (MoF, 1993). Refer to Appendix 3 for the values and consequences considered. As the project did not allow for field assessments, it should be noted that if the condition of any road was questionable the road was defaulted to a higher risk rating. To this end, all High and Very High risk roads require field assessments to determine the condition of the road and develop prescriptions for remedial work. Conversely, several areas were classified as either High or Very High risk, based on the risk rating criteria, but are known to be stable or self maintaining and were consequently not recommended for remedial work.

3.3.1. Low Risk Roads Low risk roads were assessed as those that appear stable or self maintaining. These roads typically have adequate drainage or are older sections of road with stable cut and fill


slopes and ample vegetation on the road surface. These roads may be: overgrown, located in valley bottoms, located on stable ground (bedrock or stable, well engineered slopes), located in dry areas (no or minimal overland flow or groundwater input), have fully functioning structures (ie. bridges, culverts, waterbars), and/or located in areas with slight to moderate slope. Low risk roads were considered to be low priority for future FIA funding however, where no access needs were identified, some low risk roads were proposed for deactivation.

3.3.2. Moderate Risk Roads Moderate risk roads were those that exhibited the same characteristics of low risk roads, however the consequence of a potential event was considered to be greater. Moderate risk roads were considered to be low priority for future FIA funding, unless otherwise stated.

3.3.3. High Risk Roads High risk roads were assessed as roads that show signs of problems and pose a moderate threat to the watershed and/or its users. These roads are located on or around potentially unstable or unstable terrain where the risk of a hazardous event is elevated. These roads may be impassable due to a slope failure and/or have structures that are causing environmental degradation or are unsafe to users. These roads require field assessments. These roads were considered to be areas where further FIA funding could be allocated to lower the risk to the public and the environment.

3.3.4. Very High Risk Roads Very high risk roads were assessed as roads that show signs of problems and pose a high threat to the watershed and/or its users. These roads have the same characteristics as the high risk roads but the consequence of a possible event is greater. These roads require field assessments. These roads are considered the highest priority for FIA funded remedial work.

3.4. RISK RATING RESULTS Of the 225 non-status roads or road sections identified, 13 are considered very high risk, 29 are considered high risk and the remaining 183 are considered either moderate or low risk roads. Table 2 highlights the number of roads that fall within each risk rating in the watershed. For a detailed risk rating summary by road, refer to Appendix 4.


Table 2: Number of roads or road section within each risk rating in the Cayoosh Creek Watershed. Risk Rating Number of roads or

road sections per category

Percent of total

Very High 13 5.8% High 29 12.9% Moderate & Low 183 81.3%

4. CONCLUSION The following table shows the ranked priority of the roads that should receive a field assessment. Future work should be carried out with regards to the recommendations from the field assessments. Table 3: Road Assessment/Work Priority

Road # RISK Field

Assessment/Remedial Work Priority

Comments

Van Horlick 10 (Bridge Only) VH 1

Unsafe bridge. Bridge inspection and removal if necessary.

Gott 2-1 VH 2 Known problem area. Field assessment and deactivation prescription required.

Gott 2-2 VH 3

Potentially unsafe bridges, bridge inspections required; if bridges are deemed safe, post load ratings, conduct annual bridge inspections thereafter.

23 Mile 1-2 VH 4 Known problem area. Previous instability noted, field assessment and deactivation prescription required.

Van Horlick 8-1 VH 5 Known problem area, field assessment required and deactivation prescription required.

West Boulder 1 VH 6 Road is located above unstable terrain, potential flat over steep issues. Field assessment required.

West Boulder 2 VH 7 Road is located above unstable terrain, potential flat over steep issues. Field assessment required.

Steep Creek 5-1 VH 8 Road is located on unstable terrain. Field assessment required.

Texas 1 VH 9 Field assessment required to ensure road is in self maintaining state.

Cayoosh 13.2 VH 10 Field assessment required. Cayoosh 3 VH 11 Field assessment required. Cayoosh 5 VH 12 Field assessment required. Cayoosh 5.1 VH 13 Field assessment required.

Hurley Silvermine 1-2 H 14

Road is located on potentially unstable terrain; existing slope failure in this section. Field assessment and deactivation prescription required.

Pamco 3 H 15 Road has existing slope instabilities. Field assessment required.


Road # RISK Field


Comments

23 Mile 1-1 H 16 Road is located on potentially unstable terrain. Field Assessment required.

23 Mile 1-3 H 17 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

23 Mile 2 H 18 Road is located on or adjacent to potentially unstable terrain. Field assessment required.


23 Mile 4 H 20 Road is located on potentially unstable terrain. Field assessment required.


Cayoosh 21 H 22 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Blowdown 7 H 23 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Cayoosh 26.1 H 24 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Texas 7 H 25 Field assessment required.

Downton 3 H 26 Road is on potentially unstable terrain. Field assessment required to confirm self-maintaining state.

Seton 9 H 27 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Steep Creek 3 H 28 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Hurley Silvermine 5 H 29

Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Enterprise 5 H 30 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Enterprise 4 H 31 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Texas 6.1 H 32 No access due to pulled bridge. Gott 3.1 H 33 Currently no access due to pulled bridge on Gott 3.

Van Horlick 10.5 H 34

Road is located on or near potentially unstable terrain; Overgrown; Currently no access due to pulled bridge on Van Horlick 10.2

Van Horlick 14 H 35 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Van Horlick 8.1 H 36 Road is located on or adjacent to potentially unstable terrain. Field assessment required.

Van Horlick 3-2 H 37 Road is located on potentially unstable terrain; overgrown. Field assessment required.

Van Horlick 4 H 38 Road is located on potentially unstable terrain; overgrown. Field assessment required.



Road # RISK Field


Comments


Van Horlick 7-1 H 41 Road is located on potentially unstable terrain; overgrown. Field assessment required.

Texas 6 H 42 Existing Deactivation

5. LIMITATIONS

Conclusions and recommendations presented within this report are based upon observations made from the detailed terrain stability mapping (DTSM), orthographic photos, topographic maps, local knowledge, and input from road users. Due to the nature of this assessment procedure and the lack of field assessments, it is possible that some sites may have been missed that were not identifiable on orthophotos or by road users; actual ground conditions may vary from those inferred.

This report provides a qualitative evaluation of potential landslide and erosion hazards associated with non-status roads in the project area, an estimate of the downslope/downstream landslide consequences, recommendations, and a prioritized list for future field assessments and remedial work. Acceptance of the qualitative consequence values and the subsequent risk analysis is the responsibility of the Licensees or the regulatory authority, as is the determination of acceptable risk and the decision to proceed with any action based on that risk assessment. A field assessment of the roads in snow-free conditions by a qualified registered professional is required to confirm the results of this assessment.


6. REFERENCES Ministry of Forests (MoF). (1993). Risk assessment procedure. Engineering Manual –

Chapter 8. Victoria, BC: Engineering Section, Timber Harvesting Branch (pp.7-20).

Ministry of Forests (MoF), 2004. Forest planning and practices regulation: Part 5 Roads.

Victoria, BC. Accessed March 7, 2007 at http://www.for.gov.bc.ca/tasb/legsregs/frpa/frparegs/forplanprac/fppr.htm

Ministry of Forests (MoF). (2003a). FIA activity standards document version 3

2003/2004: Standards for environmental maintenance projects on non-status forest roads. Victoria, BC. Accessed March 7, 2007 at http://www.for.gov.bc.ca/hth/documents/!publish/Engineer/fia-activity-standards-env-maint-projects-03-04.pdf

Ministry of Forests (MoF). (2003b). FIA activity standards document version 5

2003/2004: Standards for road deactivation, landslide and gully rehabilitation projects. Victoria, BC. Accessed March 7, 2007 at http://www.for.gov.bc.ca/hth/documents/!publish/Engineer/fia-activity-standards-deact-landslide-gully-03-04.pdf

Lillooet TSA Committee. (2005). Lillooet TSA sustainable forest management plan.

Accessed March 5, 2007 at http://www.for.gov.bc.ca/dcs/SustainableForestry/Lillooet/Lillooet%20SFM%20Plan%20(123105).pdf

Ministry of Sustainable Resource Management (MSRM). (2004). Draft Lillooet land

and resource management plan. Victoria, BC. July, 22, 2004. Accessed March, 5, 2007 at http://ilmbwww.gov.bc.ca/ilmb/lup/lrmp/southern/lillooet/plan/index.html

Ministry of Sustainable Resource Management (MSRM). (2007). FISS-fish distributions

query. Ministry of Sustainable Resource Management. Victoria. BC. Accessed March, 1, 2007 at http://srmapps.gov.bc.ca/apps/fidq/fissSpeciesSelect.do

Ryder, J.M. (2002). A users guide to terrain stability mapping in British Columbia.

Terrain Stability Mapping Taskforce of the Division of Engineers and Geoscientists in the Forest Sector. Vancouver, BC. Accessed March 6, 2007 at http://www.degifs.com/pdf/TS%20Mapping%20User%20Guide.pdf


APPENDIX 1

GENERAL LOCATION MAP


APPENDIX 2

DESCRIPTION OF ROAD RISK RATING CRITERIA


Appendix 2: Description of DTSM Mapping.

Definition of Classes used for Detailed Terrain Stability Mapping Terrain Stability Class Definition

I (Stable)

There are no significant problems.

II (Stable)

There is a very low likelihood of landslides following timber harvesting or road construction

III (Stable)

There is a low likelihood of landslides following timber harvesting or road construction, but the polygon may include small areas that are more susceptible to instability, such as seepage zones.

IV (Potentially Unstable)

Expected to contain areas with moderate likelihood of landslide initiation following timber harvesting or road construction; the polygon may include small areas of Class III or Class V terrain.

V (Unstable)

Expect to contain areas with high and very high likelihood of landslide initiation following timber harvesting or road construction; the polygon may include small areas of Class IV terrain.

(Source: Ryder, 2002)

Definition for “Soil Erosion Potential” Classes Class Definition VL Very low potential; no significant erosion

problems expected. L Low potential; minor erosion may occur M Moderate potential; erosion problems

should be anticipated. H High potential; major erosion problems

likely. VH Very high potential; severe erosion

problems. (Source: Ryder, 2002)


Definitions of Classes for “Risk of Sediment Delivery to Steams” Class Definition

vl Very low potential for potential for sediment from this polygon to enter a nearby stream.

l Low potential for sediment from this polygon to enter a nearby stream.

m Moderate potential for sediment from this polygon to enter a nearby stream.

h High potential for sediment from this polygon to enter a nearby stream.

vh Very high potential for sediment from this polygon to enter a nearby stream.

(Source: Ryder, 2002)


APPENDIX 3

DESCRIPTION OF ROAD CONSEQUENCE RATING


Appendix 3: Consequence Rating Consequence Rating Table

Consequence Ratings On site

downslope/downsteam

values. Low Moderate High

Water supply Areas not rated as

moderate or high.

Areas having very high water values, but less sensitive then those with high ratings (e.g., individual licensed domestic

use watershed, licensed irrigation/industrial users.

Areas having very high values which, if damaged, would

have a serious long term effect on water quality (e.g., all

community watersheds; and moderately to heavily licensed

domestic use watersheds.

Fish Habitat Areas having low fishery

values.

Areas having moderate fishery values.

Areas having high to very high fishery values.

Wildlife Habitat and Migration

Areas not rated as

moderate or high.

Areas having high wildlife values, but less sensitive then

those with high ratings.

Areas having critical importance to wildlife.

E

n

v

i

r

o

n

m

e

n

t Forestry Site Productivity

Areas not rated as

moderate or high.

Areas having moderate potential to grow merchantable

timber.

Areas having high potential to grow merchantable timber

which, if damage, would have a serious long-term effect on

regeneration.

Human life, Private property, Roads, and

Railways.

Areas that are uninhabited

and undeveloped

or occasionally

inhabited territory and

cultivated farmland.

N/A

Areas having rural development, domestic dwellings or industrial

development, highways and railways.

Utilities Areas with no utilities N/A

Areas having electric transmission towers, gas and oil lines or fibre optic cable.

Landscape (Visual) features

Areas having non-visible

development or low

landscape sensitivity.

Areas having high value for viewing, but less sensitive then

those with high ratings.

Areas having exceptionally high value for viewing.

S

o

c

i

a

l

a

n

d

E

c

o

n

o

m

i

c

Recreational features

Areas absent of, or having low, physical,

biological, cultural or

historic features.

Areas having high value for recreation, but less sensitive then those with high rating.

Areas having exceptionally high value for recreation.

(Source: MoF, 1993)


APPENDIX 4

RISK RATING SUMMARY


Appendix 4: Risk Rating Summary Road Risk Rating Data

Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration

Forestry Site Productivity

Hum

an L

ife/Private Property/R

oads/R

ailways

Utilities

Landscape (V

isual) Features

Recreational Features

Overall

Consequence

Risk (H

azard x C

onsequence)

23 Mile 1-1 4 H h H M M L L L L L L M H 23 Mile 1-2 5 VH vh H L M L L H H M M H VH 23 Mile 1-3 4 VH m-vh H M M L L L L L L M H 23 Mile 2 4 VH h H M M L L L L L L M H 23 Mile 3 4 VH h H M M L L L L L L M H 23 Mile 4 4 VH h H M M L L L L L L L H 23 Mile 5 4 H m H M M L L L L L L M H Blowdown 10 4 M - H l-m H L L L L L L L L L M Blowdown 11 4 M m H L L L L L L L L M Blowdown 11.1 L L L L L L L L L L L Blowdown 11.2 L L L L L L L L L L L Blowdown 11.3 L L L L L L L L L L L Blowdown 12 4 M - H l-h H L L L L L L L L L M Blowdown 12.1 4 H h H L L L L L L L L L M Blowdown 12.2 4 M m H L L L L L L L L L M Blowdown 12.3 L L L L L L L L L L L Blowdown 2.1 4 M h H L L L L L L L L L M Blowdown 3 4 M m H L L L L L L L L L M Blowdown 5 L L L L L L L L L L L Blowdown 5.1 L L L L L L L L L L L Blowdown 6 L L L L L L L L L L L Blowdown 7 4 H h H M M L L L L L L M H Blowdown 8 L L L L L L L L L L L Blowdown 9 L L L L L L L L L L L Boulder 1 4 H vh H L L L L L L L L L M


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Boulder 2 4 H m H L L L L L L L L L M Boulder 3 4 M m L L L L L L L L L L L Boulder 4 L M L L L L L L L M L Buddy 1 L M M L L L L L L M L Buddy 2 4 M - H m-h H L L L L L L L L L M Casper 1 4 M m H L L L L L L L L L M Casper 2 L L L L L L L L L L L Casper 3 4 M - H l-h H L L L L L L L L L M Casper 3.1 L L L L L L L L L L L Casper 3.2 L L L L L L L L L L L Casper 4 L L L L L L L L L L L Casper 5 L L L L L L L L L L L Casper 6 L L L L L L L L L L L Casper 6.1 L L L L L L L L L L L Casper 7 L L L L L L L L L L L Casper 7.1 L L L L L L L L L L L Casper 8 4 M - H l-m H L L L L L L L L L M Cayoosh 11 L L L L L L L L L L L Cayoosh 12 L L L L L L L L L L L Cayoosh 13 4 M - H m-h H L L L L L L L L L M Cayoosh 13.1 L L L L L L L L L L L Cayoosh 13.2 5 H h H L M L M H L M L H VH Cayoosh 14 L L L L L L L L L L L Cayoosh 16 L L L L L L L L L L L Cayoosh 17 L L L L L L L L L L L Cayoosh 18 L L L L L L L L L L L Cayoosh 19 L L L L L L L L L L L


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Cayoosh 20 L L L L L L L L L L L Cayoosh 21 4 M l H L L L L L L L M M H Cayoosh 21.1 4 M l H L L L L L L L L L M Cayoosh 22 L L L L L L L L L L L Cayoosh 22.1 L L L L L L L L L L L Cayoosh 23 L L L L L L L L L L L Cayoosh 23.1 L L L L L L L L L L L Cayoosh 24 L L L L L L L L L L L Cayoosh 24.1 L L L L L L L L L L L Cayoosh 25 L L L L L L L L L L L Cayoosh 26 L L L L L L L L M M L Cayoosh 26.1 4 M l H L L L L L L L M M H Cayoosh 3 5 H h H M H L L L H L L H VH Cayoosh 4 4 H m H L L L L L L L L L M Cayoosh 4.1 4 H m H L L L L L L L L L M Cayoosh 4.2 4 H m H L L L L L L L L L M Cayoosh 4.3 4 H m H L L L L L L L L L M Cayoosh 4.4 4 H m H L L L L L L L L L M Cayoosh 5 5 H vh H M H L L L L L L H VH Cayoosh 5.1 4 M h H L L L L H H M L H VH Cayoosh 6 L L L L L L L L L L L Cayoosh 7 L L L L L L L L L L L Cayoosh 9 L L M L L L L L L M L Cerise 1 4 H m H L L L L L L L L L M Cerise 10 L L L L L L L L L L L Cerise 11 L L L L L L L L L L L Cerise 11.1 L L L L L L L L L L L


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Cerise 2 L L L L L L L L L L L Cerise 3 L L L L L L L L L L L Cerise 4 L L L L L L L L L L L Cerise 5 L L L L L L L L L L L Cerise 6 4 H m H L L L L L L L L L M Cerise 7 L L L L L L L L L L L Cerise 8 L L L L L L L L L L L Cerise 9 L L L L L L L L L L L Downton 1 L M H L L L L L L H M Downton 1.1 L M H L L L L L L H M Downton 2 L M H L L L L L L H M Downton 3 4 H h H M M L M L L L L M H Downton 4 L L L L L L L L L L L Downton 4.1 L L L L L L L L L L L Enterprise 1 L L L L L L L L L L L Enterprise 2 L L L L L L L L L L L Enterprise 3 L L L L L L L L L L L Enterprise 4 4 H m H M M L L L L L L M H Enterprise 4.1 4 H m H L L L L L L L L L M Enterprise 5 4 H h H M M L L L L L L M H Gott 1 4 H h H L L L L L L L L L M Gott 1.1 4 VH vh H L L L L L L L L L M Gott 1.2 4 M h H L L L L L L L L L M Gott 1.3 4 M m H L L L L L L L L L M Gott 10 L L L L L L L L L L L Gott 10.1 L L L L L L L L L L L Gott 2-1 5 VH vh H L M L L H L L M M VH


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Gott 2-2 4 H L M L L H L L M M VH Gott 3 L L L L L L L L L L L Gott 3.1 5 H vh H L M L L L L L L M H Gott 4 4 M - H l-h H L L L L L L L L L M Gott 5 4 M m H L L L L L L L L L L Gott 5.1 L L L L L L L L L L L Gott 6 L L L L L L L L L L L Gott 7 L L L L L L L L L L L Gott 8 L L L L L L L L L L L Gott 9 L L L L L L L L L L L Hurley Silvermine 1-2 4 H h H M M L L L L L L M H Hurley Silvermine 1-1 L M M L L L L L L M L Hurley Silvermine 2 L M M L L L L L L M L Hurley Silvermine 3 L M M L L L L L L M L Hurley Silvermine 4.1 L L L L L L L L L L L Hurley Silvermine 5 5 H vh H L M L L L L M M M H Hurley Silvermine 6 L L L L L L L L L L L Hurley Silvermine 7 L L L L L L L L L L L Hurley Silvermine 7.1 L L L L L L L L L L L Hurley Silvermine 7.2 L L L L L L L L L L L Hurley Silvermine 8 L L L L L L L L L L L Hurley Silvermine 9 L L L L L L L L L L L Pamco 1 L L L L L L L L L L L Pamco 2 L L L L L L L L L L L Pamco 2.1 L L L L L L L L L L L Pamco 3 H M L L L L L L L M H Pamco 4 L L L L L L L L L L L


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Pamco 5 L L L L L L L L L L L Seton 1 L L L L L L L L L L L Seton 10 L L L L L L L L L L L Seton 11 4 H h H L L L L L L L L L M Seton 12 L L L L L L L L L L L Seton 13 L L L L L L L L L L L Seton 14 L L L L L L L L L L L Seton 15 L L L L L L L L L L L Seton 16 L L L L L L L L L L L Seton 2 L L L L L L L L L L L Seton 3 L L L L L L L L L L L Seton 4 4 M h H L L L L L L L L L M Seton 4.1 4 M h H L L L L L L L L L M Seton 5 L L L L L L L L L L L Seton 6 L L L L L L L L L L L Seton 7 L L L L L L L L L L L Seton 8 L L L L L L L L L L L Seton 8.1 L L L L L L L L L L L Seton 9 4 M - H h H L M M L L L L L M H Steep Creek 1 L L L L L L L L L L L Steep Creek 2 4 H h H L L L L L L L L L M Steep Creek 3 4 H h H M M L L L L L L M H Steep Creek 4 4 H h H M M L L L L L L L M Steep Creek 5.1 L L L L L L L L L L L Steep Creek 5.2 L L L L L L L L L L L Steep Creek 5-1 5 H h H M H L L L L L L H VH Steep Creek 5-2 L L L L L L L L L L L


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Steep Creek 6 L L L L L L L L L L L Steep Creek 5.3 L L L L L L L L L L L Texas 1 5 L h H M H M L L L L M H VH Texas 10 L L L M L L L L L M L Texas 11 4 H h L L L M L L L L L M L Texas 12 4 H h L L L M L L L L L M L Texas 12.1 4 H h L L L M L L L L L M L Texas 13 L L L M L L L L L M L Texas 13.1 L L L M L L L L L M L Texas 13.2 L L L M L L L L L M L Texas 14 L L L M L L L L L M L Texas 14.1 L L L M L L L L L M L Texas 14.2 L L L M L L L L L M L Texas 14.3 L L L M L L L L L M L Texas 14.4 L L L M L L L L L M L Texas 14.5 L L L M L L L L L M L Texas 14.6 L L L M L L L L L M L Texas 14.7 L L L M L L L L L M L Texas 2 L L L M L L L L L M L Texas 3 L L L M L L L L L M L Texas 4 L L L M L L L L L M L Texas 5 L L L M L L L L L M L Texas 6.1 4 H vh H L L M L L L L L M H Texas 6 4 M -H vh H M M M L L L L M M H Texas 7 4 H h H M M M L L L L L M H Texas 7.1 L L L L L L L L L L L Texas 7.2 L L L M L L L L L M L


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Texas 7.3 L L L M L L L L L M L Texas 8 4 H h L L L M L L L L L L L Texas 9 L L L M L L L L L M L Van Horlick 1 L L L L L L L L L L L Van Horlick 10 L L M M L L L L L M L Van Horlick 10 (Bridge only) 5 H vh H L M M L H L L H H VH Van Horlick 10.1 L L L M L L L L L M L Van Horlick 10.2 L L L M L L L L L M L Van Horlick 10.3 L L L M L L L L L M L Van Horlick 10.4 L L L M L L L L L M L Van Horlick 10.5 4 M m-h H L M M L L L L L M H Van Horlick 10.6 L L L M L L L L L M L Van Horlick 11 L L L M L L L L L M L Van Horlick 12 L L L M L L L L L M L Van Horlick 12.1 L L L L L L L L L M L Van Horlick 13 4 M vh H L L L L L L L L L M Van Horlick 14 4 M m H L M M L L L L L M H Van Horlick 14.1 L L L L L L L L L L L Van Horlick 14.2 L L L L L L L L L L L Van Horlick 15 4 M m H L L L L L L L L L M Van Horlick 16 4 M m H L L L L L L L L L M Van Horlick 2 4 H m H L L L L L L L L L M Van Horlick 3-1 L L L L L L L L L L L Van Horlick 3-2 4 H-VH h H L M L L L L L L M H Van Horlick 4 4 H h H M M M L L L L L M H Van Horlick 5 4 H h H M M M L L L L L M H


Road #

Terrain C

lass

Soil Erosion

Potential

Risk of

Sediment

Delivery to Stream

s

Hazard

Water Supply

Fish Habitat

Wildlife H

abitat and M

igration


Hum

an L


oads/R

ailways

Utilities

Landscape (V

isual) Features


Overall

Consequence

Risk (H

azard x C

onsequence)

Van Horlick 6 4 H m-vh H L M M L L L L L M H Van Horlick 7.1 4 H m H L L L L L L L L L M Van Horlick 7.2 L L L M L L L L L L L Van Horlick 7-1 4 H m H L M M L L L L L M H Van Horlick 7-2 L L L M L L L L L M L Van Horlick 8.1 4 M-H m H L L M L L L L L M H Van Horlick 8-1 5 VH vh H L M M L H L L L M VH Van Horlick 8-2 L L M M L L L L L M L Van Horlick 9 L L L M L L L L L M L Van Horlick 9.1 L L L M L L L L L M L West Boulder 1 5 VH vh H M H L L L L M L H VH West Boulder 2 5 VH vh H M H L L L L M L H VH


APPENDIX 5

RISK ASSESSMENT MAP

Download - CAYOOSH CREEK WATERSHED - British Columbia · Cayoosh Creek Watershed 1 Watershed Risk Assessment 1. INTRODUCTION 1.1. PROJECT OVERVIEW This Watershed Risk Assessment (WRA) is funded

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