city of revelstoke greeley creek watershed source protection plan 2013

7/27/2019 City of Revelstoke Greeley Creek Watershed Source Protection Plan 2013

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July 8, 2013

DRINKING WATER SOURCE-TO-TAP ASSESSMENT

City of RevelstokeGreeley Creek WatershedSource Protection Plan

R E P O R T

Report Number: 1214930116-001-R-Rev0

Distribution:Distribution:

City of Revelstoke - 2 Copies

Golder Associates Ltd. - 1 Copy

Submitted to:City of Revelstoke

Attn: Penny Page-Brittin - Sustainability Coordinator PO Box 170216 McKenzie AvenueRevelstoke, BC, V0E2S0

AgendaItem#7f. AgendaItem#7f. AgendaItem#7f. AgendaItem#7f.

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GREELEY CREEK WATERSHED SOURCE PROTECTION PLAN

July 8, 2013Report No. 1214930116-001-R-Rev0 i

Acknow ledgements

This project is suppor ted by the Columbia Basin Trusts Communities Adapting to Cl im ate In it iat ive (CACCI) www .cb t.o rg /cl im atechang e

Technical Advi sory Commit tee

Golder wishes to thank the following organizations and their representatives for their membership in theTechnical Advisory Committee and their valuable contributions to this source protection plan.

Communities Adapting to Climate Change InitiativeMs. Katherine Mahoney, Coordinator Ms. Cindy Pearce, Technical SupportMr. Jeff Zukiwsky, Project Liaison

City of RevelstokeMr. Tony Edwards, former Acting Director of Engineering and Public Works

Mr. Robert Girard, Fire Chief Mr. Gordon Hall, Engineering TechnologistMr. Darren Komonoski, Operations Manager Ms. Penny Page-Brittin, Environmental Sustainability Coordinator Mr. Doug Pendergast, Utilities ForemanMr. Mike Thomas, P.Eng., Director of Engineering and Public Works

Downie Timber Ltd.Mr. Dieter Offermann, Planning Forester

Interior Health Author ityMr. Robert Fleming, Drinking Water Officer

Ministry of Forests, Lands and Natural Resource OperationsMr. Kevin Lavelle, Stewardship Officer


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July 8, 2013Report No. 1214930116-001-R-Rev0 ii

Executive Summary

Golder Associates Ltd. has developed a source watershed protection plan for the Greeley Creek drinking water source, which follows Modules 1, 2, 7, and 8 of the BC Comprehensive Drinking Water Source-to-Tap

Assessment (CS2TA) Guideline and is required under the Provincial Drinking Water Protection Act for the CitysPermit to Operate. There are eight Modules under the CS2TA Guideline, but the objective of this plan is toaddress only those that characterize Greeley Creek and consider risks and recommendations for drinking water protection at the watershed level. The Citys water treatment and distribution, operations and maintenance, andfinance and governance, which are the focus of Modules 3 through 6, are not considered or included as part of this Plan.

Development of this Plan followed the general methods outlined in:

(a) the Modules 1, 2, 7 and 8 of the CS2TA Guideline; and,

(b) the requirements of the Request for Proposals issued by the City of Revelstoke, including a review of information regarding projected climate changes in the Columbia River basin to define a climate changescenario for the 2050s.

The climate change scenario forms the basis for an assessment of potential climate change impacts to the water supply from the Greeley Creek Watershed. To supplement previously published regional scale climate changeprojections, Golder extracted more detailed data using the ClimateWNA software tool to consider projectedclimate variables within the watershed assessment area to the year 2050.

Golder conducted a review of available information in order to complete the watershed characterization anddevelopment of a preliminary hazard identification table, summarizing the drinking water hazards identified for the Watershed Assessment Area.

Golder developed the hazard and risk matrix to qualitatively rank the drinking water hazards based on theavailable information reviewed based on qualitative criteria for each likelihood and consequence rating.These relative risk rankings developed by Golder and modified in consultation with the Technical AdvisoryCommittee (TAC) following thier review of the draft report. The risk rankings presented herein have beenupdated to incorporate feedback from the TAC.

Based on the risk characterization, for current conditions, the identified existing intrinsic and land use activitydrinking water hazards, listed by relative risk, were:

High Risk mass movements, stream channel instability, and, climate change

Moderate Risk wildfire, wildlife, and avalanches

Low Risk windthrow, forest insects and disease, forestry, and ski recreation




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July 8, 2013Report No. 1214930116-001-R-Rev0 iii

Hazards related to potential future development were:

High Risk other recreation (snowmobiling, hiking, mountain biking, ATVs, motorcycling and camping)

Moderate Risk placer and mineral mining

Low Risk roads and infrastructure and hydroelectric power generation.

For the projected climate change scenario, the risk characterization for the identified existing intrinsic and landuse drinking water hazards changed such that mass movements increased to very high risk, wildfire, wildlife androads and infrastructure increased to high risk, and forests, insects and disease, forestry, and hydroelectricpower generation increased to moderate risk.

A set of recommended actions to improve drinking water protection (Module 8 of the CS2TA Guideline) weredeveloped, which incorporate feedback from the City, other members of the Technical Advisory Committee andpublic feedback from the Open House. These included:

1) Conduct Assessment of Back-up Water Supply Elements

2) Address Access Issues

3) Assess and Mitigate Wildfire Risks

4) Emergency Response

5) Institute Flow and Climate Monitoring Program within Greeley Creek WAA

6) Water Supply Management

7) Climate Adaptation

8) Long-term Monitoring of Terrain and Channel Stability

9) Development of Watershed Stakeholder Groups or Committees

10) Application for mineral, petroleum and coal no staking reserve




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July 8, 2013Report No. 1214930116-001-R-Rev0 iv

Table of Contents

1.0 INTRODUCTION ............................................................................................................................................................... 1

1.1 Watershed Setting ............................................................................................................................................... 1

1.2 City of Revelstoke Water System ........................................................................................................................ 1

1.2.1 Greeley Creek Source ................................. .................................... ..................................... .......................... 1

1.2.2 Back-up Sources .................................. ................................... ................................... .................................... 2

1.3 Drinking Water Hazards .................................. .................................... ............................................ ..................... 3

1.4 Scope of Work ..................................................................................................................................................... 4

2.0 PROJECT METHODS ...................................................................................................................................................... 5

3.0 MODULE 1 WATERSHED CHARACTERIZATION ....................................... ....................................... ......................... 9

3.1 Greeley Creek Watershed Setting ......................................................... ................................... ........................... 9

3.1.1 Geographic and Geomorphic Overview ................................... ................................... ................................... 9

3.1.2 Bedrock Geology.......................................................................................................................................... 10

3.1.3 Biogeoclimatic Setting .............................. .................................. .................................. ................................ 10

3.1.4 Fish Status ................................................................................................................................................... 11

3.2 Greeley Creek Watershed Characterization ............................................................. ........................................ . 11

3.2.1 Climate ......................................................................................................................................................... 11

3.2.2 Water Use and Streamflow .................................................. ..................................... ................................... 14

3.2.3 Water Quality ............................................................................................................................................... 18

3.3 Greeley Creek Watershed Air Photo Review ............................... ................................... ................................... 19

3.4 Greeley Creek Municipal Water Intake ..................................................... ................................... ...................... 19

3.4.1 Description of Water Intake ................................. .................................... ........................................ ............. 19

3.4.2 Evaluation of Water Intake .................................. .................................. .......................................... ............. 21

3.5 Greeley Creek Watershed Intrinsic Hazards ............................. ................................... ...................................... 21

3.5.1 Wildfire ......................................................................................................................................................... 23

3.5.2 Wildlife ......................................................................................................................................................... 24

3.5.3 Mass Movements .................................. .................................. ................................... .................................. 24

3.5.4 Avalanches ................................ .................................... .................................... ........................................ .. 24

3.5.5 Windthrow .................................................................................................................................................... 24

3.5.6 Stream Channel Stability ................................... ..................................... .................................... .................. 24




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3.5.7 Forest Insects and Disease ............................... ................................... ................................... ..................... 25

3.5.8 Climate Change ........................................................................................................................................... 25

3.6 Greeley Creek Watershed and Projected Climate Change ............................. .................................. ................. 25

4.0 MODULE 2 CONTAMINANT SOURCE INVENTORY ................................................................................................. 30

4.1 Existing Land Use in W atershed Assessment Area ................................ .................................... ....................... 31

4.1.1 Forestry ........................................................................................................................................................ 32

4.1.1.1 Potential Impacts ...................................................................................................................................... 32

4.1.1.2 Regulation of Forestry Activities ..................................................... ..................................... ..................... 33

4.1.1.3 Forestry Activities in WAA ........................................................................................................................ 33

4.1.2 Ski Recreation .................................. ................................... ................................... ...................................... 34

4.2 Potential Hazards Related to Development in the Area .................................. .................................... ............... 35

5.0 MODULE 7 RISK CHARACTERIZATION ................................................................................................................... 35

5.1 Evaluation of Drinking Water Protection Barriers ............................... .................................. .............................. 36

5.2 Risk Assessment ............................................................................................................................................... 37

6.0 MODULE 8 RECOMMENDED ACTIONS TO IMPROVE DRINKING WATER PROTECTION .......................... ......... 41

7.0 LIMITATIONS ................................................................................................................................................................. 46

8.0 REFERENCES ................................................................................................................................................................ 47




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July 8, 2013Report No. 1214930116-001-R-Rev0 vi

TABLES (IN TEXT)

Table 1: Water Licences held for Greeley Creek (complete list of attributes is in Appendix C). ................................................. 2

Table 2: Environment Canada Climate Station for Revelstoke, BC. ................................... .................................... .................. 11

Table 3: Values shown on Figure 2 (bold values are maximum and minimum). ............................. .................................. ....... 12

Table 4: WSC Hydrometric Stations on Greeley Creek. ...................................... ....................................... .............................. 15

Table 5: Summary of Air Photos Reviewed for Greeley Creek Watershed Source Protection Plan. ................................. ....... 20

Table 7: Evaluation of Greeley Creek Water Intake. .................................................................. ...................................... ........ 22

Table 8: Summary of Climate Change Impacts for the Columbia-Shuswap in the 2050's (PCIC 2012). .................................. 26

Table 9: Greeley Creek Watershed Projected Climate Variables to 2050 Using ClimateWNA. ............................. .................. 27

Table 10: Contaminant Inventory. ............................................ ..................................... ....................................... .................... 30

Table 11: Timber Agreements within Watershed Assessment Area. .............. .................................. ...................................... . 33

Table 13: Qualitative Measures of Probability .................................. .................................. ........................................ .............. 37

Table 14: Qualitative Measures of Consequence ................................ ................................... ................................... ............... 38

Table 15b: Abated Risk Analysis Matrix. ............................... .................................. ....................................... .......................... 39

Table 17a: Abated Drinking Water Hazard Risk Assessment for Current Conditions. .............................................. ............... 40

Table 17b: Abated Drinking Water Hazard Risk Assessment for Projected Climate Change Scenario ............ ....................... 40

TABLES (FOLL OWING TEXT)

Table 7: Hazard Identification

Table 12: Drinking Water Barriers Assessment

Table 16a: Risk Characterization for Current Conditions

Table 16b: Risk Characterization for Projected Climate Change Scenario

Table 18: Recommended Risk Management Actions

FIGURES

Figure 1: Outline of Module 1 from the CS2TA (MHLS 2010). ......................................................... ....................................... ... 9

Figure 2: Average monthly temperature recordings at Revelstoke Airport Road (Environment Canada 1971 -2000). ..... ..... .... 12

Figure 3: Average monthly rainfall, snowfall, and precipitation at Revelstoke Airport Road (Environment Canada 1971-2000). ...................................................................................................................................................................... 13

Figure 4: City of Revelstoke monthly water consumption from 2001-2011..................................... ................................... ....... 14

Figure 5: City of Revelstoke annual water consumption from 2001-2011 (Jan. and Feb. missing in 2001). ............................ 15

Figure 6: WSC hydrometric flow data on Greeley Creek from stations 08ND021 and 08ND024. ............................................ 16

Figure 7: Mass curves using WSC data from stations 08ND021 and 08ND024..................................................... .................. 17

Figure 8: City of Revelstoke available streamflow data on Greeley Creek. ................................... .................................... ....... 18

Figure 9: Monthly total precipitation in WAA for historic and projected future time frames .............................. ......................... 28

Figure 10: Monthly precipitation as snow in WAA for historic and projected future time frames ............................................. . 28




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July 8, 2013Report No. 1214930116-001-R-Rev0 viii

LIST OF ABBREVIATIONS AND ACRONYMS

AAC Annual Allowable Cut

BCWMB BC Wildfire Management Branch

CS2TA Comprehensive Drinking Water Source to Tap Assessment Guideline

FL Forest License

FRPA Forest and Range Practices Act

FSP Forest Stewardship Plans

GCDWQ Guidelines for Canadian Drinking Water Quality

IHA Interior Health Authority

masl metres above sea level

MOE British Columbia Ministry of Environment

MOFR British Columbia Ministry of Forest and Range

MFLNRO Ministry of Forests, Lands, and Natural Resource Operations

NPV nuclear polyhedrosis virus

NTU nephelometric turbidity units

ROW Right-Of-Way

RMR Revelstoke Mountain Resort

SFMP Sustainable Forest Management Plan

SFIP Sustainable Forestry Initiative Program

SRES Special Report on Emissions Scenarios

TAC Technical Advisory Committee

TSA Timber Supply Area

TSR Timber Supply Review

TDS Total dissolved solids

UBCM Union of BC Municipalities

WAA Watershed Assessment Area

WSC Water Survey of Canada

WTP Water Treatment Plant




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July 8, 2013Report No. 1214930116-001-R-Rev0 1

1.0 INTRODUCTION As requested by the City of Revelstoke (the City), Golder Associates Ltd. (Golder) has developed a sourcewatershed protection plan for the Greeley Creek drinking water source , hereafter referred to as this Plan This Plan follows Modules 1, 2, 7, and 8 of the BC Comprehensive Drinking Water Source-to-Tap Assessment(CS2TA) Guideline (MHLS 2010) and is required under the Provincial Drinking Water Protection Act for the CitysPermit to Operate. There are eight Modules under the CS2TA Guideline, but the objective of this plan is toaddress only those that characterize Greeley Creek and consider risks and recommendations for drinking water protection at the watershed level. The Citys water treatment and distribution, opera tions and maintenance, andfinance and governance, which are the focus of Modules 3 through 6, are not considered or included as part of this Plan.

The Greeley Creek watershed is located in the Columbia River basin within the Kootenay Hydrologic Region(Zone 22 Lower Columbia Basin [Coulson and Obedkoff 1998; Obedkoff 2003]) and this basin has beenproactive in considering potential impacts of changing climate conditions to biophysical and social componentsof their watersheds (CBT 2012a); therefore, an abundance of regional-scale data is available regarding projectedclimate change impacts in the basin. The City of Revelstoke is also forward-thinking in this manner and thereforewished for the available climate change data to specifically be included in this Plan. As such, Golder hasincluded one climate change scenario in this Plan, and discussed potential impacts of climate change on thewatershed throughout this report.

1.1 Watershed SettingGreeley Creek is situated in the Selkirk Mountains east of Revelstoke. The watershed for Greeley Creek isroughly bound by Revelstoke Mountain Resort to the west, the Illecillewaet River to the north and undevelopedforested land to the east and south (Map 1, Appendix A). The Illecillewaet River flows to the west/southwest,discharging into the Columbia River, which then flows in a southerly direction.

1.2 City of Revelstoke Water SystemGreeley Creek is the Citys primary source of drinking water, with a secondary water source supplied bygroundwater well TW02-3, located at the Revelstoke Golf Club (Map 1, Appendix A). The City has two additional,surface water licenses, located on Bridge Creek and Hamilton Creek (Map 1, Appendix A), both of which aredesignated as Community Watersheds. The Bridge Creek and Hamilton Creek licenses are not currently in useby the City and neither source is connected to the Citys water supply infrastructure. Note the City groundwater well and additional surface water intakes are located outside of the watershed area for Greeley Creek, and arenot included in this Plan.

1.2.1 Greeley Creek Sour ceSurface water from Greeley Creek enters a series of small settling ponds before entering the Greeley CreekWater Treatment Plant (WTP), which is capable of supplying up to 175 L/s of treated water to the City (refer tothe photo plates in Appendix B). The WTP uses a micro-filtration membrane and chlorination system to treat thesurface water source. The treated water is fed down to the City by a buried gravity system that goes under Illecillewaet River and then follows the alignment of the Trans-Canada Highway (Map 1, Appendix A). There are




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currently two reservoirs, Trans-Canada Highway and Arrow Heights (Map 1, Appendix A) with a combined

capacity of 6,820 m 3, two booster stations (Arrow Heights and Revelstoke Mountain Resort [RMR]), andapproximately 98 km of distribution system that are divided into five pressure zones in the City (CoR 2012).This water system serves approximately 7,000 residents through approximately 2,996 residential and 310commercial water connections (CoR 2012).

There are three Provincial Water Licences currently held for Greeley Creek (Map 2, Appendix A). The City hastwo of these Water Licences (C047974 and F011233), and both are intended for potable water supply (municipalwaterworks). The allowable quantity for these two Licences is approximately 0.21 m 3/s (210 L/s) 1.There is a third Water Licence (C100606) for Greeley Creek held by a private owner and the intended use is for residential power, with an allowable quantity for this licence of 0.085 m 3/s (85 L/s). A list of these Water Licenceswith key information is in Table 1, and a complete list with all information is provided for reference in Appendix C.

Table 1: Water Licences held fo r Greeley Creek (complete list of attr ibutes i s in Appendi x C).

Licence No. Licensee Purpose Priori ty Date Quantity (m 3/s)

C047974 City of Revelstoke Waterworks July 13, 1976 0.158C100606 L Birkenbach & F. Nakao Residential Power December 11, 1989 0.085F011233 City of Revelstoke Waterworks November 17, 1930 0.053

As part of the Provincial Drinking Water Protection Act , in order to meet the terms and conditions of the CitysPermit to Operate (issued by the Health Authority), the City is required to complete a Source Water ProtectionPlan for their water source. The purpose of the plan is to identify conditions and activities that could affect thequality and quantity of water from Greeley Creek such that the City can influence planning and measure potentialimpacts on the water system. The City is working together with, and as a member of, the Columbia Basin Trust(CBT) Communities Adapting to Climate Change Initiative (CACCI) on this project.

1.2.2 Back-up Sources

The City has three available back-up water sources: Bridge Creek, Hamilton Creek and the Golf Course Well;however, only the Golf Course is connected to the water supply system and actively in use at this time. BridgeCreek and Hamilton Creek are surface water sources while the Golf Course Well is a groundwater source.

The Golf Course Well is completed in a confined aquifer that is considered to have low vulnerability tocontamination from surface sources as it is protected by a thick silt layer. A Wellhead Protection Plan completedfor the Golf Course Well (Golder, 2007) included a pumping test to assess the well capacity and capture zone of the well for groundwater protection planning purposes. The Golf Course Well is presently limited (by regulation)to providing water at a rate of approximately 6,393 m 3/day (74 L/s). Successful completion of appropriateenvironmental assessments (depending on the funding agencies either a Provincial or a Federal Assessment or if both agencies were involved, a harmonized assessment) would allow the well to operate at 9,072 m 3/day

(105 L/s) with the flow limit being based on a maximum well screen entrance velocity of 0.03 m/s. Based on theresults of the testing, the report inferred that the Golf Course Well is capable of producing all of the

1 The actual Water Licences are listed to have an allowable quantity of 6,637,291.4 m 3/year and the units have been converted in this plan assuming 365 days in a calendar year.




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then-projected 2015 average day demand of 10,464 m 3/day (121 L/s); however, at the time of the report it was

assumed that the majority of that demand would be provided by the existing treatment plant at Greely Creek.

It is understood that the City is currently undertaking a detailed assessment of water demand and the finalresults are not yet available. Based on the monthly water use data available in the City of Revelstoke 2011

Annual Water Report, for 2001-2011, monthly water use ranges from a low of 122,163 m 3 recorded in November 2011 to a high of 329,798 m 3 recorded in July 2003, which correspond to average daily demands of 47 L/s and123 L/s, respectively. Thus, it is apparent that the Golf Course Well has the capacity to meet the highest averagedaily demand reported to date; however, it is unclear whether the maximum daily demand could be met, asthese numbers are not available.

It is noted that the Golf Course Well capacity was assessed using a test pump and that the well was notconnected to the water distribution system at the time of testing, which is standard procedure for conductingpumping tests. To assess the capacity of the water system to operate using only the Golf Course Well, onewould need to consider the performance of the well with the duty pump connected to the distribution system.

1.3 Drinking Water HazardsGreeley Creek is the primary source of water to the City, and although the watershed is largely undeveloped atthe time of writing this Plan, there are potential natural and anthropogenic hazards that could affect drinkingwater quality and quantity in the future. By definition from the CS2TA (MHLS 2010) and for the purpose of thisreport, a hazard is an agent(s) of harm that can adversely af fect a water supply. One of the primary goals of this plan is to identify potential hazards and assign a risk rating to each one, where the risk rating is comprised of two metrics: a likelihood and a consequence.

Drinking water hazards are related to either water quality or water quantity, as these are the characteristicsimportant to the City and its approximately 7,000 customers or 3,300 connections. As the water purveyor to thismany people and local businesses, the safety and security of Greeley Creek is very important to the City.This plan identifies the potential hazards to Greeley Creek, assesses the risk of each hazard, and looks to

provide recommendations on mitigation to some of the key hazards.

Water quality characteristics include the physical, chemical, and biological parameters that are used to describeand measure water. In BC, two particular water quality guidelines are considered when assessing drinking water quality: the Approved Water Quality Guidelines, issued by the BC Ministry of Environment, and the Guidelinesfor Canadian Drinking Water Quality GCDWQ (Health Canada 2012), developed by theFederal-Provincial-Territorial Committee on Drinking Water. These guidelines provide criteria for manyparameters such as turbidity, nutrients, and specific chemical substances. Natural and undeveloped watershedsoften do not have significant water quality issues. However, there are still potential risks.

Water quantity is also an important parameter for the City to consider in their long-term planning for water security. It can be affected by many factors and the changes may be related to:

Temporal fluctuations (i.e., peaks coming earlier or later than normal); or,

Volume fluctuations (i.e., more volume at one time or lower peak over longer period).




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Current City staff members provided anecdotal data that in their experience, there have not been any problems

or shortages in water supply in Greeley Creek, even during lower winter low flows (Penny Page-Brittin, pers.comm. 2012). That being said, water quantity is still an important parameter to evaluate, especially whenconsidering potential future climate change and any uncertainty there may be in water supply. If the water demand from the City exceeds the available flows in Greeley Creek at any time during the year there will be adeficit in water supply to the City from the WTP.

1.4 Scope of Work As described in Golders proposal, the scope of work for this Plan is to:

Complete a watershed source protection plan for Greeley Creek following Modules 1, 2, 7, and 8 of theCS2TA;

Module 1 is to delineate and characterize the drinking water source.

Module 2 is to conduct a contaminant source inventory.

Module 7 is to characterize the risks from source-to-tap.

Module 8 is to recommend actions to improve drinking water protection.

Perform a site visit to the water intake and readily accessible areas of the lower watershed;

Include relevant impacts of future climate projections to the year 2050 for the Columbia Region;

Work with and include input from City staff and the Technical Advisory Committee (TAC); and,

Attend a public open house to present the draft report.

In total there are 8 Modules in the CS2TA, and Modules 3, 4, 5, and 6 are beyond the scope of this Plan.The Modules that are not being assessed in this Plan are:

Water supply elements (Module 3);

Water system management and operations and maintenance (Module 4);

Auditing water quality and availability (Module 5); and,

Financial capacity and governance (Module 6).

Golders scope of work did not include a site visit to the mid to upper watershed. There are no roads to theseareas and although a helicopter flight was considered as additional work, this was not proposed or completedbecause the costs associated outweighed the benefits for the City.




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Reports relevant to the Greeley Creek Watershed available on the Provincial Government Websites,(Ministry of Environment (MOE) and/or Ministry of Forests, Lands and Natural Resources Operations(MFLNRO);

Review of relevant previous studies conducted by Golder in the area (Golder, 2001, 2002 and 2007);

Water Management Reports (City of Revelstoke, 2007, 2010, 2011 and 2012);

Relevant online data and mapping for the Greeley Creek Watershed such as, land use and permits, climatedata, hydrometric data, topographic maps, surficial and bedrock geology maps, contaminated sites registry;

Aerial photographs covering the Greeley Creek Watershed, provided by the Geographic Information Centreat the University of BC Department of Geography, and the Ministry of Forests, Lands, and NaturalResource Operations (MFLNRO); and,

Information collected from interviews conducted with City of Revelstoke representatives.

In addition, Golder reviewed information regarding projected climate changes in the Columbia River basin(Columbia Basin Trust (CBT) 2012 and Pacific Climate Impacts Consortium (PCIC) 2012a) to define a climatechange scenario for the 2050s, which forms the basis for an assessment of potential climate change impacts tothe water supply from the Greeley Creek Watershed. To supplement this published work by the PCIC,Golder extracted more detailed data using the ClimateWNA software tool (Wang et al. 2012) to consider projected climate variables within the watershed assessment area to the year 2050. Golder assessed theidentified risks to the Greeley Creek drinking water supply source for current conditions, and for the definedclimate change scenario, using the Columbia Basin Trust document (CBT 2012a) as a resource.

Details regarding the cl imate change scenario are presented in Section 3.6, while the results of Golderspreliminary risk assessment and recommended actions to improve drinking water protection (Modules 7 and 8 of the CS2TA Guideline) are discussed in Section 5.0 and Section 6.0, respectively. The risk assessment andrecommended actions include input obtained from the TAC following review of the draft report.

Task 4: Watershed Characterization (Module 1)The Greeley Creek watershed was assessed and characterized based on information collected in Task 3,and from Golders observations during the site visit . Golders observatio ns also included a review and evaluationof the Citys water intake. The air photo review was performed using imagery provided by the sources notedabove and included a review of the following:

Watershed geomorphology;

Forest cover vegetation;

Road network and watershed access;

Stream network, order, and density;

Natural resource activity; and,

Existing infrastructure.




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Task 5: GIS MappingThe information collected during the data and literature review and field reconnaissance was used to develop aGeographic Information System (GIS) model of the Study Area. An electronic copy of the GIS project data isprovided on a DVD in Appendix E, in ArcGIS format, and includes the following map layers:

Watershed boundary and watershed assessment area;

Key features of the City of Revelstoke water supply system (reservoirs, intake and well locations);

Stream channel and water treatment plant infrastructure locations;

Important bio-geophysical and topography information;

Terrain, slopes, and soil types;

Land use and tenure;

Wildfire risk mapping;

Locations of potential contaminant sources (sediment sources, land use risks, naturalor human risks, etc.); and,

The relative risk ranking of specific identified drinking water hazards and vulnerabilities.

Task 6: Field Review and Validation (Modules 1 & 2)Following the information review, Golder conducted a field reconnaissance visit on November 20, 2012.Mr. Geoffrey Cahill of Golder was accompanied on the reconnaissance by Ms. Penny Page-Brittin andMr. John Buhler, both with the City of Revelstoke. Due to the limited access to the watershed assessment area,

the field review was limited to the areas of the Citys water intake, Water Treatment Plant, and an area of recentforestry operations to the east of the water intake. The field review included completion of an evaluation of theGreeley Creek intake, as outlined in Table 1-3 of Module 1 in the CS2TA Guideline.

Golder assessed the need and usefulness of conducting a helicopter survey within the watershed at the proposalstage of work and based on the limited use within the watershed, it was Golders opinion that the costsassociated with a helicopter survey outweighed the benefits to the City at this time.




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Task 7: Risk Assessment and Recommendation s (Modules 7 & 8) Areas of concern (Hazards) to water quality and quantity in the Greeley Creek watershed were identified fromthe reviewed data and field investigations through a risk assessment, based on a standard ranking of Likelihoodand Consequence to produce a 5-Class ranking of Risk.

: Golder prepared a risk assessment for currentconditions and one future scenario to explore potential impacts from climate change, as discussed below.Golder used the hazard and risk matrix to qualitatively rank the watershed based on the available informationbased on qualitative criteria for each likelihood and consequence rating from 1 (rare or insignificant) to 5 (certainor catastrophic) for each potential watershed hazard (based on Table 7-3 in the CS2TA Guideline). The matrixwas constructed to reflect the likelihood, consequence, and overall risk relevant to local and regional concernsand conditions based on the reviewed information.

Task 8: ReportingDraft Watershed Assessment Report

As per Golders proposal, a draft report was issued to the City on January 30, 2013. The document wasreviewed by the TAC, and a teleconference call (Meeting 3, see below) was held to obtain input from the TAC inorder to complete the risk assessment and provide recommendations, and for feedback on the overall report.

Final Draft Watershed Assessment ReportGolder incorporated changes based on one set of review comments from the City and TAC, into a second draftreport, issued on April 9, 2013, which was reviewed by the City of Revelstoke and the CACCI members of theTAC.

Final Watershed Ass essment Report

The final report incorporates comments from the Public Open House (Meeting 4, see below), the City, membersof the Technical Advisory Committee, and other stakeholders.

Task 9: Project Meetings As identified previously, Golder allocated time for four project meetings consisting of i) a teleconference projectinitiation meeting, ii) a face-to-face 1-hr meeting with the representatives from the City of Revelstoke held on thesame day as the field reconnaissance, iii) a teleconference meeting to present the results of the draft report tothe Technical Advisory committee, and iv) a face-to-face meeting to present the draft results in an open house.

The public Open House meeting was held at the Revelstoke Community Centre on May 15, 2013 by Ms. Pattie Amison of Golder, Ms. Penny Page-Brittin of the City of Revelstoke and Mr. Jeff Zukiwsky of Communities Adapting to Climate Change. The event was publicized several weeks in advance by placing notices in the localnewspapers and putting up posters at the Community Centre. The entire report, including poster sized colour printouts of the report maps and drinking water hazard tables were made available for examination by the publicand comment sheets were provided for feedback. Two members of the local media were in attendance, inaddition to several members of City Council and approximately 30 members of the general public.




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3.0 MODULE 1 WATERSHED CHARACTERIZATIONThe objectives of Module 1 from the CS2TA are outlined in Figure 1, and the following Sections assess andcharacterize Greeley Creek following this guideline.

Figure 1: Outline of Module 1 from the CS2TA (MHLS 2010).

Golder has delineated the Greeley Creek watershed contributing to the water intake and this is shown in Map 1in Appendix A. The contributing watershed area is approximately 46.2 km 2, which forms one part of

the watershed assessment area (WAA). The second part of the WAA is the intake protection zone (Map 2, Appendix A). Golder has defined the intake protection zone as a 150 m radius around the intake site, which isslightly larger than the recommended minimum of 100 m in the CS2TA. The larger radius for the intakeprotection zone accommodates recent forestry operations near the intake and recognizes the importance of theintake location.

3.1 Greeley Creek Watershed Setting3.1.1 Geographic and Geomorphic Overview

Greeley Creek drains a watershed area of approximately 47.7 km 2 and discharges into Illecillewaet River approximately 8 km upstream of the confluence of the Illecillewaet with the Columbia River. Approximately46.2 km 2 of the watershed contributes to the water supply area. The watershed rises nearly 2,000 m in elevation

from the Illecillewaet valley to Ghost Peak and Mount Mackenzie, which lie at approximately 2,490 m and2,450 m elevation, respectively (Map 1, Appendix A). The watershed primarily has a north-facing aspect anddrains the mountain slopes in a dendritic (branching) pattern. At the confluence with Illecillewaet River, theelevation is approximately 516 m and the Citys water intake is at an elevation of approximately 627 m.

Greeley Creek is situated within the Selkirk Mountains, which lie between the Monashee Mountains to the westand Purcell Mountains to the east. Collectively, these three ranges form part of the Columbia Mountainsand Southern Rockies physiographic region (Valentine et al. 1994). Approximately 9 km to the west is theColumbia River (Arrow Lake) that separates the Selkirk and Monashee Mountains. This is a mountainous regionin the province and is generally characterized by warm, moderately dry summers and cool-cold, moderately wetwinters (Moore et al. 2010).

The existing landscape in and around Greeley Creek has been influenced by the last glaciation and thegeomorphic processes that have occurred over the Holocene. In the alpine and headwater areas there are

remnant glacial landforms such as cirques, artes, and tarns, and this area exhibits rugged and steep terrain.Ghost Peak is a horn situated above three cirques (two of which are in the Greeley Creek watershed and one of which is outside). Below the cirques, the stream channels in the watershed are generally steep and confinedbetween even steeper banks and slopes, which is consistent with a geologically young system. On average, themain channel from above the intake up to the headwaters has a longitudinal gradient of approximately 12% andmany of the reaches and tributary streams are even steeper.

1. Delineate theContributingWatershed

2. Define theAssessment Area

3. Characterizethe Watershed

and Water Body

4. Evaluate theIntegrity and

Location of theIntake




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Because Greeley Creek is steep and confined throughout the mid to upper reaches, it is incising into the parent

material and transporting sediment downstream where an alluvial fan exists at its lowest reaches.Golder observed reaches near the intake and on the fan to characterize the bed form of Greeley Creek.The channel has a step-pool form (MoF 1996a) near the intake and the bedload is a mix of gravels and sandswith large boulders up to approximately 1 m in diameter. Downstream of the intake on the fan, the channel has ashallow riffle form with a finer bedload composition (sands, gravels, and cobbles up to 0.3 m in diameter).The apex of the alluvial fan is located near the base of the mountains near to where the existing water intake issituated (approximately 627 m elevation). The fan has a total length of approximately 1.4 km, and the run-out toeabuts Illecillewaet River. On the alluvial fan, Greeley Creek is crossed by three bridges; two on local roads andthe other on the CP mainline railway and there has been channel training works constructed upstream of therailway.

3.1.2 Bedroc k Geology

The Selkirk Mountains are one of the ranges that comprise the larger Columbia Mountains and SouthernRockies, which are noted to have complex bedrock geology (Valentine et al. 1994). According to theweb-mapping available from the BC Geological Survey (Map 3, Appendix A), the bedrock geology in thewatershed is from the Paleozoic Era, primarily Cambrian to Devonian. The lower watershed (following east-westIllecillewaet valley) consists of Devonian orthogneiss metamorphic rocks. The mid and high elevation portions of the watershed consist primarily of a mix of sedimentary rocks, Cambrian to Devonian, Lardeau Group (Index,Broadview, and Badshot Formations), including:

Mudstone;

Siltstone;

Shale;

Limestone;

Slate;

Argillite; and,

Calcareous Sedimentary Rock.

3.1.3 Biogeocli matic Settin g According to mapping available through GeoBC (Map 4, Appendix A) in the lower elevations of the watershedthe biogeoclimatic zone is classified as Interior Cedar-Hemlock (ICH) and as elevations rise, the zones changeto Engelmann Spruce-Subalpine Fir (ESSF) and Interior Mountain-heather Alpine (IMA). The forested areas of this watershed have wet-cool and wet-cold characteristics. Mapping suggest that stand-initiating naturaldisturbance events (NDT Type I) are rare, meaning that large events such as wildfire or insect infestations areuncommon in these ecosystems. Typical tree species in the watershed include western red cedar (Thuja plicata ), western hemlock ( Tsuga heterophylla ), subalpine fir ( Abies lasiocarpa ), hybrid white spruce(Picea glauca x engelmannii ), and western white pine ( Pinus monticola ). The lower and mid elevation areas of the watershed are forested and the upper watershed has subalpine and alpine areas with sparse or no trees




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present. Most of the forest vegetation is mature and there are younger, second growth stands developing in the

slide tracks. The alpine areas accumulate heavy snow in the winter, and because the watershed has anorth-facing aspect there may be some portions of the watershed that have snowpack all-year. The watershedincludes an intact small glacier, located just to the east of Ghost Peak.

3.1.4 Fish StatusGolder did not perform any fish sampling or investigation work specifically for this Plan, but the lower reaches of Greeley Creek have been previously confirmed as fish-bearing waters (MEC 1998). Fish sampling was notcompleted in the mid and upper reaches of the watershed in this study, but bull trout ( Salvelinus confluentus )were observed and recorded in the lower, readily accessible reaches. The steep longitudinal gradient of the mainchannel (approximately 12% on average) could be a potential barrier to fish migration to upstream reaches athigher elevations. The only lakes in the watershed are high-elevation tarns, which will likely be nutrient-poor

(oligotrophic) and not fish-bearing. Fish presence in Greeley Creek can be a function or indicator of overallwatershed health, but not necessarily linked to drinking water quality or quantity.

3.2 Greeley Creek Watershed Character izationThe Greeley Creek watershed is a 4 th order system with a total area of approximately 47.7 km 2; above the Cityswater intake the watershed area is approximately 46.2 km 2. There are approximately 79 km of total streamlength including the tributaries currently mapped above the intake, so the drainage density of Greeley Creek is1.72 km/km 2:

There are limited climate and streamflow data available for Greeley Creek and the surrounding area. The closestclimate station is near the Revelstoke Airport, approximately 9 km to the west of the watershed. The streamflowdata record for Greeley Creek is discontinuous and incomplete. The following sections characterize the climateand streamflow information that were readily available.

3.2.1 Climate

Climate data are not collected at the water intake site or in the upper watershed of Greeley Creek. The nearestdata source is near the Revelstoke Airport operated by Environment Canada (Map 1, Appendix A). Details onthis station are shown in Table 2. Golder has reviewed the most current available Climate Normals publishedonline from 1971-2000 2 (Environment Canada 2012). The elevation of the water intake is approximately 177 mhigher than this station.

Table 2: Envir onment Canada Climate Station for Revelstoke, BC.

Station Name Climate ID Latitud e Longi tude Elevation

Revelstoke Airport Road 1176751 50 57 12 118 09 59 450 m

2 Environment Canada 1981-2010 Climate Normals are not available at this time




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Figure 2 and Table 3 show the average monthly temperatures for this climate station. The daily average

temperature ranges from -5.3 C in January to 18.2 C in July. The daily average minimum is -8.2 C and the dailyaverage maximum is 25.3 C. The extreme minimum daily temperature is -29.4 C recorded on January 17, 1970and the extreme daily maximum is 37.2 C recorded on June 26, 1992. There are distinct seasons recorded atthis station, where the warmest months are June to August and the coldest months are December to February.Daily average temperatures recorded at this station begin a warming trend in April and May and stay warm untilOctober when they begin to cool again. There is an orographic effect on temperature (Moore et al. 2010;Dingman 2005) and the higher elevations in this watershed will have a lag, with the warming trend occurring later than the recordings at this station.

Figure 2: Average monthly temperature recordings at Revelstoke Airport Road (Environment Canada 1971-2000).

Table 3: Values shown on Figu re 2 (bold values are maximum and mini mum).

Month Daily Minimum ( C) Daily Average ( C) Daily Maximum ( C)

January -8.2 -5.3 -2.2

February -5.9 -2.5 0.9March -2.7 1.8 6.3

April 1.2 7.3 13.4May 5.7 12.6 19.4June 9.5 16.1 22.6July 11.1 18.2 25.3

August 11.0 17.9 24.6September 7.0 12.6 18.3October 2.7 6.7 10.6November -1.6 0.8 3.2December -6.2 -3.8 -1.4

-10

-5

0

5

10

15

20

25

30

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

T e m p e r a t u r e ( C )

Daily Average Daily Maximum Daily Minimum




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Figure 3 shows the rainfall, precipitation, and snowfall depths recorded at the Environment Canada climate

station on Revelstoke Airport Road. The rainfall and precipitation depths (shown on the primary axis) are for average monthly values based on daily recordings. Precipitation values represent water equivalents for bothsnowfall and rainfall. The snowfall depths (shown on the secondary axis) are for average accumulated snowfallat the end of each month. Rainfall and precipitation fall throughout the year. Based on the period of record for this station, on average, snowfall has accumulated and been recorded for six months each year; typicallyNovember through April. Snowfall is the primary form of precipitation in the winter months (December toFebruary) and rainfall is the primary form of precipitation from May through October. In an average year, thisstation has recorded 618 mm of rainfall and 946 mm of precipitation. The average depth of snow isapproximately 4.25 m per year.

Figure 3: Average monthly rainfall, snowfall, and precipitation at Revelstoke Airport Road (Environment Canada 1971-2000).

There is also an intensity-duration-frequency (IDF) curve published for the data collected at this climate station,and this has been included in Appendix F. IDF curves are a plot of rainfall intensity (ordinate) against rainfallduration (abscissa) for different hydrologic return periods. They are constructed using historical data and arefrequently used to design municipal stormwater infrastructure. Environment Canada periodically updates the IDFcurves, and if data is available, when compared over time these curves can be used to identify shifts in rainfallcharacteristics due to changing climate conditions or other local factors.

The Environment Canada climate station is situated along the Columbia River near the Revelstoke Airport(Map 1, Appendix A), lower in elevation, and approximately 9 km west of Greeley Creek. Because there is asignificant elevation gain of approximately 2,000 m and the watershed has a north-facing aspect there will bedifferences to the temperatures and total precipitation values described. It can be inferred that the headwatersand higher elevation areas will generally be colder, have more snowfall, and a longer winter season (Moore et al2010; Eaton and Moore 2010). As elevations decrease in the watershed, more similarity can be inferred to thedata recorded at this station and only the climate trends discussed above can be projected for the watershedarea of Greeley Creek.

0

200

400

600

800

1000

1200

1400

0

20

40

60

80

100

120

140

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

S n o w f a l l D e p t h ( m m )

R a i n a n d P r e c i p i t a t i o n D e p t h ( m m )

Rainfall Precipitation Snowfall




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3.2.2 Water Use and Streamflow

The Citys WTP was constructed in 2000 and the City provided Golder with water use 3 data recorded from2001 through 2011 (Figures 4 and 5 and Appendix G; January and February 2001 data not included in theseFigures). Monthly water use levels are generally consistent from year-to-year over this period and the highestwater demand is from May through September. The peak months for these years has been July or August,where on average approximately 248,500 m 3 of water is supplied to the City from the WTP. From October through March, the average monthly water use is approximately 165,000 m 3. During this period, the averagetotal annual water use in the City is approximately 2,220,000 m 3 .

Figure 4: City of Revelstoke monthly water consumption from 2001-2011.

3 The term water use is used in this report to generally describe the amount of water being supplied to the City from the WTP . It may not be directly consumed by customers as there areother factors, such as water loss in the distribution system, which may account for some of this water volume.

100,000

150,000

200,000

250,000

300,000

350,000

W a t e r C o n s u m p t i o n ( m 3 )

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011




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Figure 5: City of Revelstoke annual water consumption from 2001-2011 (Jan. and Feb. missing in 2001).

Because of its physiographic location and hydrologic characteristics, Greeley Creek is characterized by asnowmelt dominated hydrologic regime. The peak of the annual hydrograph typically occurs at some point in thelate spring or early summer months. From the late summer through to the early spring, typical streamflow inGreeley Creek will be low. Base flow likely occurs in either late summer (September) or mid-winter (January-February) depending on how dry the summers or how cold the winters have been. If the base flowswere to ever drop below the Citys water demand for a period of time, there could be a water deficit if the supplyand storage cannot be sustained.

Streamflow data have been recorded for Greeley Creek by two agencies: the Water Survey of Canada (WSC)

and the City, with monitoring locations shown on Map 2 in Appendix A. In 1984 and 1985, two hydrometricstations were established and data were recorded for one year by the WSC. These stations, listed in Table 4,and shown on Map 2 in Appendix A are now discontinued. Current City employees were not aware of thesestations, where they were established, and why they were only recorded for one year. Daily streamflow data arepresented in Figure 6, which shows that the recorded peaks in Greeley Creek were 7.52 m 3/s on June 27, 1984(#08ND021) and 9.17 m 3/s on May 25, 1985 (#08ND024). The dates of these peaks are consistent with theclimate data assessed and the hydrologic regime. At higher elevations, heavy winter snowfall is kept in storageuntil warming temperatures are sustained long enough to begin melting the snowpack. The rising flow in thespring months from snowmelt is termed freshet, and the peak timing will vary from year -to-year but will likelyoccur between late May and July. After freshet flows recede, the streamflow decreases through the summer months to a base flow level. These data are limited, but the summer base flows recorded by the WSC in1984 and 1985 are approximately 1-1.5 m 3/s. Greeley Creek has high elevations and a northern aspect, alongwith an existing (small) glacier, which will all contribute to late summer and fall base flows.

Table 4: WSC Hydrometri c Stations on Greeley Creek.

StationID Station Name Latitud e Longi tude

Drainage Area (km 2) Record Length

08ND021 Greeley Creek Above Diversion 51 0 35 118 3 37 47.0 Apr. 19 - Oct. 3, 1984

08ND024 Greeley Creek Near The Mouth 51 1 2 118 3 40 47.6 Apr. 30 - Oct. 1, 1985

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

W a t e r C o n s u m p t i o n ( m 3 )




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Figure 7: Mass curves using WSC data from stations 08ND021 and 08ND024.

Since 2007, the City has been collecting flow measurements on Greeley Creek at the bridge crossing onGreeley Road approximately 1.2 km downstream from the intake site at an elevation of approximately 528 m(Map 2, Appendix A). Dayton & Knight Ltd. completed an analysis on the initial two years of data and maderecommendations on water management (D&K 2009); one of which was to complete this water managementplan, now being completed by Golder. The City provided Golder with the monitoring data for 2007, 2008, 2009,and 2012 (Appendix H). Data were not collected in 2010 and 2011.

Figure 8 shows the data from these years, but it is noted that these data are not continuous and there are manydays missing. A technician from the City visits the site periodically to record depth and velocity measurements

from the bridge, and a flow estimate is derived by the velocity-area method. The data presented on Figure 8 areincomplete and no inferences have been made to assume flows between days or missed recordings. In 2007there were 41 site visits, in 2008 there were 33, in 2009 there were 7, and in 2012 there were 13. The recordedpeaks are between 5.1-7.6 m 3/s and occurred between May 30 and July 4 during these years. Due to the datagaps, there is no certainty that the timing of the site visits aligned with the actual peak. Although these data aresparse, the general trend is consistent with the WSC hydrometric station data. Freshet peaks in Greeley Creekcan be expected to occur between late May and July, and outside of the rising and falling limbs of the annualhydrograph the watershed will primarily be conveying base flows.

0

5,000,000

10,000,000

15,000,000

20,000,000

25,000,000

30,000,000

35,000,000

40,000,000

45,000,000

C u m u l a t i v e F l o w V o l u m e ( m 3 )

08ND021 (1984) 08ND024 (1985)




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Figure 8: City of Revelstoke available streamflow data on Greeley Creek.

The City streamflow data show measurements made outside the months recorded by the WSC. There is greatvalue in having measurements completed throughout the year in order to see the full annual hydrograph andhydrologic regime of the system. Depending on the type of device used to measure water velocity there could beerrors and limitations at low water depths; however, from the data collected by the City, base flows wereestimated to be in the range of approximately 0.25-0.40 m 3/s (or 250-400 L/s). These base flows are above thecurrent treatment and supply capacity of the Citys water treat ment plan (175 L/s) by 43-129%.These measurements represent only a small sample in time and the City should strongly consider setting up amore permanent monitoring station.

3.2.3 Water Quality

Raw water quality in Greeley Creek is sampled by the City and tested once per year by an independentlaboratory. The 2012 test results are included for reference in Appendix I.

A review of water quality testing is outside the scope of work for this Plan, as it is covered in Module 5 (AuditWater Quality and Availability) of the CS2TA; however, Golder reviewed the results of the 2012 in order toassess the general quality of the source water. Based on the analytical chemistry results for the sample takenon December 4, 2012, the raw water quality in Greeley Creek is considered good, with none of the parametersanalyzed for, including turbidity, exceeding the GCDWQ. Total coliforms were detected; however, these are notused as indicators of potential health effects from pathogenic microorganisms, but rather they are used as anoperational tool to assess effectiveness of a drinking water treatment system.

0

1

2

3

4

5

6

7

8

29-Nov 18-Jan 9-Mar 28-Apr 17-Jun 6-Aug 25-Sep 14-Nov 3-Jan 22-Feb

F l o w ( m 3 / s )

2007 Data 2008 Data 2009 Data 2012 Data




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3.3 Greeley Creek Watershed Air Photo ReviewGolder requested air photos available from the Geographic Information Centre (GIC) at the University of BCDepartment of Geography and obtained five flights from 1951 through 1984. Refer to Table 5 showing the flightyears and photo numbers. The Ministry of Forests, Lands, and Natural Resource Operations (MFLNRO) office inRevelstoke also provided Golder with a more recent flight from 1996. These flight lines are also shown inTable 5, along with Golders observations and comments for all the photos. Along with this air photo review,Golder has also reviewed the current imagery available in Google Earth.

3.4 Greeley Creek Municipal Water IntakeGolder performed a site visit on November 20, 2012 to the Citys water intake on Greeley Creek with twoCity staff members: Penny Page-Brittin (Environmental Sustainability Coordinator/Project Manager) andJohn Buhler (Utility Person/Relief Foreman). Selected representative photos from this site visit are included in

Appendix B. Golder did not review design or construction record drawings of the intake site and the followingdiscussion is based on Golders site observations.

3.4.1 Descript ion of Water Intake Access to the City water intake (and Water Treatment Plant) is off Greeley Road and the entrance is gated andlocked with signage indicating that access is for Authorized Personnel Only and No Trespassing (refer to photoin Appendix B). The turnoff is located in a rural location and there is minimal developed land nearby. The start of the access road is also at the beginning of an active resource road and requires crossing the CP mainlinerailway. The water intake site is located approximately 1.3 km up the access from the turnoff and this accessroad does not go anywhere else (Map 2, Appendix A).

The water intake is a relatively simple hydraulic structure situated on the left bank of Greeley Creek near theapex of the alluvial fan at an elevation of approximately 627 m. There is a sliding gate intake on the left bank thatcan be controlled by an adjustable in-stream weir structure. The weir is comprised of segmental concrete blocks(Lock -Blocks) that hav e notches cut for large timber ties to be placed across the stream. As streamflowchanges the weir height can be adjusted to back-water the channel and ensure water is supplied through thegate. The timber ties are placed with a one-tonne overhead crane that is mounted at the site. Approximately 5 mdownstream of the weir are constriction walls on both banks, which are constructed of two rows of segmentalconcrete blocks. The walls constrict the channel from approximately 7 m down to 3 m in width. Golder hasassumed that these constriction walls are a hydraulic control on the streamflow, which assists in back-wateringthe channel at different stages. There is a large precast concrete pad (bed) immediately downstream of theseconstriction walls and downstream of this pad is a vertical drop of approximately 1 m down to what is assumed tobe the natural channel bed.




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Table 5: Summary of Ai r Photos Reviewed for Greeley Creek Watershed Source Protection Plan.

FlightYear

Photo Numbers /Flight Lines

Air Ph oto Observat ions and Comment s

1951 A 13246 No. 205-207

- Photos only cover southern (high elevation) portion of watershed- Flight coverage does not include present intake location- Headwaters of Greeley Creek has multiple cirque, arte, and tarn features from

past glaciers and glacial processes- Watershed drainage pattern is dendritic- No roads or resource activity observed in mid or upper watershed- There are steep erosional features (tracks) from avalanches and/or mass

movements in the headwaters- Majority of watershed has mature forest cover; except high elevation alpine

areas in headwaters- There are steep tributaries to main channel along east valley slopes

1952 A 13491 No. 62-64

- Coverage is for full watershed- There is a large disturbance area (possible fire) in the forest vegetation on the

east, lower-mid slope of the watershed- There are no discernible changes since 1951 in upper watershed- Current intake and access road not constructed

1961

BC4002: No. 171-177 - Three flight lines completed at a larger scale- There are two landslide scars in the large disturbance area noted in 1952- There is a bank failure on the left bank of Greeley Creek in the lower reach of

the channel (upstream of current intake location)- Glacier to the east of Ghost Peak is visible and intact- There appears to be very few changes from the 1951/52 photos- Current intake and access road not constructed

BC4003: No. 174-181

BC4004: No. 19-26

1970 BC5378 No. 81-83

- There are possibly two bank failures in the watershed: one on the main GreeleyCreek channel and one on a steep tributary

- Still very few changes from the 1951/52 photos- Current intake and access road not constructed

1984 BC84030 No. 33-35

- There are forest roads and cutblocks on and near the top of the alluvial fan

(primarily in Illecillewaet valley)- Road to current intake location appears to be cut in but ponds or infrastructureare not visible

- Forest disturbance area in lower watershed has greened -up - Another landslide is visible at the top of this large disturbance area, which flows

down into a tributary stream- No discernible changes in the upper watershed

1996

BCB96042 No. 18-21 - Photos do not cover all of headwater/alpine area- Additional logging area added to cutblock visible in 1984 photo, up to current

intake area that is clearly visible- A settling pond has been constructed at intake site- No discernible changes in the upper watershed

BCB96042 No. 59-61

BCB96042 No. 100-103

n/a Google Earth

- Image resolution and coverage is good (photo year is labelled 2011 in mid andlower watershed; 2001 in high elevations)

- No discernible changes in the upper watershed- Intake, settling ponds, and Water Treatment Plant are constructed

- Low elevation forest cutblocks have greened -up - A new resource road has been constructed above the right bank above the

intake; approximately 150 m upslope from intake




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The intake system has two settling ponds upstream of the Water Treatment Plant and water from Greeley Creek

flows through the sliding gate control into the firs t settling pond. There is second sliding gate control between thefirst and second settling ponds. The first settling pond has a surface area of approximately 300 m 2 with a gravel(natural) bed. There are two hydraulic controls on this pond:

1) Level control with overflow channel and direct connection back to Greeley Creek; and,

2) Sliding gate control with connection to second settling pond.

The second settling pond has a surface area of approximately 1,500 m 2 with a concrete floor and gravel sideslopes. The concrete floor is sloped to a low-point near the downstream end of the pond adjacent a manholestructure that contains a screen and intake pipe to the Water Treatment Plant. There is also a level control onthis pond that flows back into Greeley Creek.

The City performs annual maintenance in both settling ponds to clean out sediment accumulation and ensure the

system is functioning properly. Anecdotally, this is typically performed in the fall when flows recede and theponds are readily accessible. During this time the demand for water use from City customers also recedes andthere may potentially be less risk if the system must be shut down for maintenance.

3.4.2 Evaluation of Water Intake

One of the objectives in Module 1 of CS2TA is to evaluate the integrity and location of the intake. Based onGolders observations, Table 6 provides an evaluation of the Greeley Creek water intake.

3.5 Greeley Creek Watershed Intr insic HazardsThere are intrinsic hazards to the Greeley Creek watershed that are described below and included in the

Drinking Water Hazard Identification Table 6 (at end of text) (Hazard No. 1-1 to 1-8).Intrinsic hazards can derive from many factors and are site specific to the watersheds natural characteristics.They are important to identify so that the City is aware of the nature and character of them, so they can monitor and manage their source water supply accordingly. The following section provides a brief account of the intrinsichazards that have been identified for Greeley Creek.




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Table 7: Evaluation of Greeley Creek Water Intake.

Factor Comments and Evaluation

Location and Depth

- The intake is located near the apex of the alluvial fan, which should generally be astable channel location

- The intake is located at an elevation of approximately 627 m, which provides enoughstatic head to feed the City by gravity without the need for power (pumping)

- The depth of the two settling ponds appeared adequate at approximately 1 to 1.5 m,which is shallow enough to easily dredge and deep enough for settling and ice

Design

- Overall intake design is simple and effective- The adjustable in-stream weir provides adaptability to different streamflow stages- The sliding gate valves are readily accessible and provide control (these should be

periodically operated to ensure they dont seize) - There are level and overflow controls on both settling ponds

Accessibility

- The water intake is approximately 8 km east of the City administrative boundary- There is a single site access road off of Greeley Road, which is gated and locked

- The weir, intake, and settling ponds are easily accessible by personnel, vehicles, andequipment for operation and maintenance- The site is generally accessible by others who want to get in- There are no physical barriers to wildlife accessibility and migration

Flow

- Flow conveyance into and through the intake and settling ponds appears adequate- There are level controls and overflows in ponds allowing for circulation- The second settling pond has a sloped concrete floor to allow for maintenance and

improve water circulation

Stability and Erosion

- There are no obvious signs of instability or erosion- The site is situated at the apex of the alluvial fan, so the channel is generally stable- Through construction, the site has been graded and there is riprap armouring and

segmental concrete blocks to reduce and general stability risks

Sedimentation- Both settling ponds are very accessible by Public Works crews and equipment to

remove sediment accumulations- The concrete floor in the second settling pond allows for efficient cleaning

Ice

- Due to the elevation and geographic location, it is expected that ice could form on thesurface layer of these settling ponds (not observed by Golder)

- The level controls on the two ponds allow for water circulation to reduce ice buildup- The water depths in both ponds appear adequate to avert freezing risks- The settling ponds are open to the environment with no physical cover

Protection

- Although this is a rural location and signage exists at the beginning of the road, theintake site is accessible by people that may want to see or access this area

- There is no perimeter fencing or physical barriers- Wildlife can easily access the intake and settling ponds- Ski tracks have reportedly been seen at the intake site




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3.5.1 Wildfire

Wildfires occur in BC every year and although some are caused by human errors many are caused by seasonalweather conditions, when hot and dry spells are followed by lightning storms. Naturally occurring wildfires are notpreventable and this is a hazard that the City needs to be aware because of the associated risks to water qualityand quantity. The City recently completed a Community Wildfire Protection Plan and Golder reviewed a draftversion of this document (MLI et al. 2011). Greeley Creek was not specifically addressed in the CommunityWildfire Protection Plan, as the watershed is outside the administrative boundary of the City, but many of theconclusions and fire risk ratings can be applied because of the similar climate, ecosystem, and physiographiccharacteristics. The forested ecosystems in the watershed (ICH and ESSF) are generally wet and cool, and haverare stand-initiating natural disturbance events. During the air photo review a large disturbance area wasidentified (in 1952 photo) in the watershed that was possibly a wildfire. Possible effects of wildfire onGreeley Creek include (Pike et al. 2010a; Winkler et al. 2010):

The loss of mature forests, riparian vegetation, and understory vegetation;

The exposure of mineral soil layers and loss of forest humus and organics;

The potential for hydrophobic soils that reduce infiltration capabilities and can increase runoff;

The use of chemical retardants and foams in fires suppression operations;

The resulting changes to the hydrologic regime of Greeley Creek; and,

The possibility of stream channel instability and movements.

Wildfire Risk assessments have not been conducted for the entire WAA; however, some areas were included inwildfire risk mapping conducted as part of the most recent Revelstoke and Area Community Wildfire ProtectionPlan (MLI, 2011), and a Fire Smart assessment of the area around water intake was conducted by The City of Revelstoke Utilities, Revelstoke Fire Rescue Services, related Forest agencies and the Community Wildfire

Protection Plan consultant in the fall of 2012. Although areas of moderate to high fire risk were identified by MLI(2011), as shown on Map 10 (Appendix A), results of the Fire Smart assessment indicated that the City of Revelstoke Water Treatment facility is considered a low hazard area for wildfires and fuel hazards in the area didnot merit fuel management due to the amount of soil moisture, the young open deciduous stand of treesadjacent to the water treatment plant and the lack of ladder fuels in the older forests, which is of a self-pruningtype (Girard 2013, pers. comm.).

However, there is the potential for wildfires to impact large areas of watershed, and it is noted that thecommunity wildfire protection plan does not include drinking water risks (MLI 2011). It is understood that wildfireprotection in the WAA is outside of the jurisdiction of the City due to the fact that the BC MoE StewardshipBranch is responsible for wildfire management and BC Wildfire Management Branch is responsible for wildfireprotection; therefore, there is the potential for the communication structure to increase the risk of impact to thedrinking water supply as a result of wildfire. In addition, lack of access and steep slopes increase difficulty incontrolling wildfires within the WAA, and the recently proposed Revelstoke Adventure Park could result inincreased access to the WAA and bordering areas by the public and increased risk for human-initiated wildfires.




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3.5.2 Wildlife

Greeley Creek is a natural and undeveloped watershed that could provide habitat and migration corridors for many animals. Larger animals, like ungulates, can cross streams which may cause minor amounts of erosion or turbidity problems. Animal use and habitat within the intake protection zone is another hazard to consider.Wildlife, including birds, can be carriers or vectors for some serious pathogenic microorganisms such as Giardia ,Cryptosporidium , and cholera that can all cause serious health problems for humans.

3.5.3 Mass Movements

Terrain stability mapping has been previously completed for Greeley Creek and this shows many areas that arepotentially unstable and unstable ( Map 5, Appendix A). Based on the air photo review, there is evidence of landslides in the watershed and some of these reach the stream network, which introduces sediment into thesystem in episodic pulses. A large amount of sediment in the system can be significant concern to water quality

and stream processes. This can also be a concern at the water intake, settling ponds, and Water TreatmentPlant, where th

city of revelstoke greeley creek watershed source protection plan 2013

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