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Assessment of Potential Water Storage Sites and Diversion Scenarios (January 2008)

Pub No: T/854 ISBN 978-0-7785-7354-8 (Printed Edition) ISBN 978-0-7785-7355-5 (On-line Edition) Disclaimer This document is an independent report requested by, and prepared for, Alberta Environment. The authors are solely responsible for the interpretationsof data and statements made within this report. The report does not necessarily reflect endorsement by, or the policies of Alberta Environment. Reproduction and Availability This report and its contents may be reproduced in whole, or in part, provided that this title page is included with such reproduction and/or appropriate acknowledgements are provided to the authors and sponsors of this project. Any comments, questions or suggestions on the content of this document may be directed to: Alberta Environment Communications 10th Floor, Petroleum Plaza South Tower 9915-108 Street Edmonton, AB T5K 2J6 Tel: 780.427.2700 (outside of Edmonton dial 310.0000 for toll-free connection)Fax: 780. 422.4086 E-mail: [email protected] Website: www.gov.ab.ca/env

Additional Copies Additional print copies of this document are available from: Alberta Environment Information Centre Main Floor, Oxbridge Place 9820-106 Street Edmonton, AB T5K 2J6 Tel: 780.427.2700 (outside of Edmonton dial 310.0000 for toll-free connection) Fax: 780. 422.4086 E-mail: [email protected] Website: www.gov.ab.ca/env Copyright of this publication, regardless of format, belongs to Her Majesty the Queen in right of the Province of Alberta. Reproduction of this publication, in whole or in part, regardless of purpose, requires the prior written permission of Alberta Environment. © Her Majesty the Queen in right of the Province of Alberta, 2008

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Alberta Environment Assessment of Potential Water Storage Sites

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EXECUTIVE SUMMARY

As part of the Water for Life initiative to provide “reliable, quality water supplies for a sustainable

economy”, MPE Engineering Ltd. assessed, by major river basin, previously identified potential water

storage sites and diversion scenarios in Alberta. An assessment tool was developed that considers several

technical and subjective criteria, and uses a weighted scoring system to rate and compare sites within the

same basin. The sites are grouped so the user receives a simple visual indication of sites more favourable

for further investigation and evaluation.

In 2005, as part of Water for Life, MPE Engineering Ltd. compiled an inventory database of previously

identified potential water storage sites and diversion scenarios in Alberta. These sites are the subject of

the current assessment. Of the 238 sites identified in the 2005 inventory, 59 sites are diversion (either

inter-basin or intra-basin) segments with no storage component and are not assessed. The remaining 179

sites are classified as either “on-stream” or “off-stream” storage sites and are assessed. Three additional

potential on-stream storage sites were found in available reports from the 2005 inventory study and are

also included in the assessment, for a total of 182 assessed sites.

Of the 182 assessed sites, 92 had incomplete information for the assessment, so their scores are

consequently reduced. The assessment results are presented in Appendix E.

The assessment tool, comprised of ten worksheets, is built with Microsoft Excel©, which provides

relative ease of use and flexibility in how the information is used and presented. The weighting and

grouping intervals can be changed as the perceived importance of each criterion may change. The scores,

weightings and groupings (in Appendix E and on disk in Appendix F) have been scrutinized by several

individuals with significant experience in water resources. As such, any change to their values should be

justifiable and reasonable before the user considers implementing the change.

The assessment tool is not intended to determine if a site should be developed. Rather, the assessment

tool allows the user to compare sites within the same major river basin to help determine if a site

warrants further investigation and evaluation.

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New sites can also be added to the assessment tool to make comparisons with those already identified.

The assessment tool could be enhanced to obtain more meaningful assessments and site comparisons.

Some of the tool’s current limitations include missing or incomplete source information, the variability of

information quality from one site to another, and the various outdated design standards from one site to

another.

The Microsoft Excel© platform limits the type of analysis that can be done. For instance, the sites on one

worksheet cannot be “sorted” because this will produce errors in the other worksheets. However, sites can

be “filtered” to display only those sites which meet the filtering criteria.

As a safeguard, the user is strongly encouraged to make a backup copy before using the assessment tool.

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TABLE OF CONTENTS

EXECUTIVE SUMMARY

ACKNOWLEDGEMENTS

1.0 INTRODUCTION ......................................................................................................................................... 2

2.0 SCOPE OF WORK ....................................................................................................................................... 3

2.1 SPECIFIC STUDY CRITERIA .......................................................................................................................... 4

3.0 DEVELOPMENT OF THE ASSESSMENT TOOL .................................................................................. 6

3.1 ASSESSMENT TOOL WORKSHEETS .............................................................................................................. 6 3.1.1 1 - Guideline ........................................................................................................................................ 7 3.1.2 2 - Summary ........................................................................................................................................ 7 3.1.3 3 – Supply-Demand ............................................................................................................................ 7 3.1.4 4 - Environment .................................................................................................................................. 8 3.1.5 5 - Site Availability ............................................................................................................................. 8 3.1.6 6 - Geotechnical ................................................................................................................................... 8 3.1.7 7 - Storage Efficiency .......................................................................................................................... 8 3.1.8 8 - Dam Safety ..................................................................................................................................... 8 3.1.9 9 - Other Considerations .................................................................................................................... 9 3.1.10 10 - Background .................................................................................................................................. 9

3.2 ASSESSMENT CRITERIA AND PARAMETERS ................................................................................................. 9 3.2.1 Selection of Criteria and Parameters ............................................................................................... 12 3.2.2 Scores ................................................................................................................................................. 16 3.2.3 Weightings ......................................................................................................................................... 16 3.2.4 Groupings........................................................................................................................................... 16

3.3 QUESTIONNAIRES ...................................................................................................................................... 17 3.4 WORKSHOPS .............................................................................................................................................. 17

4.0 ASSESSMENT OF POTENTIAL STORAGE SITES ............................................................................. 19

4.1 DEFINITION OF “ON-STREAM” AND “OFF-STREAM” .................................................................................. 19 4.2 INFORMATION SOURCES AND INFORMATION QUALITY ............................................................................. 19 4.3 ASSESSED SITES ........................................................................................................................................ 20

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5.0 DISCUSSION .............................................................................................................................................. 22

5.1 LIMITATIONS AND DATA GAPS .................................................................................................................. 22 5.1.1 Data .................................................................................................................................................... 22 5.1.2 Methodology ....................................................................................................................................... 23 5.1.3 River Basins ....................................................................................................................................... 23

5.2 NEXT STEPS FOR SITE INVESTIGATIONS AND EVALUATION ....................................................................... 23

6.0 RECOMMENDATIONS ............................................................................................................................ 25

7.0 REFERENCES ............................................................................................................................................ 27

APPENDICES

APPENDIX A GEOTECHNICAL ASSESSMENT

APPENDIX B ENVIRONMENTAL & HISTORICAL RESOURCES ASSESSMENT

APPENDIX C WORKSHEET CONTENTS AND EXPLANATIONS

APPENDIX D USING THE ASSESSMENT TOOL – WITH EXAMPLES

APPENDIX E ASSESSMENT RESULTS – PRINTOUTS PRESENTED BY RIVER BASIN

APPENDIX F INSTALLATION DISK

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ACKNOWLEDGEMENTS

Many Alberta Environment staff provided important assistance in the compilation of information used in

this assessment. We acknowledge their cooperation and assistance.

Kent Berg, Calgary

Garry Bucharski, Edmonton

Chiadih Chang, Spruce Grove

Al Corbett, Spruce Grove

Ed Hoyes, Edmonton

Rick Friedl, Innisfail

Saba Gnanakumar, Calgary

Anil Gupta, Calgary

Patrick Marriott, Edmonton

Bob Sharp, Edmonton

Tom Tang, Calgary

Kevin Wilkinson, Calgary

Janet Yan, Edmonton

We also acknowledge the cooperation and assistance of John Brandon, Heritage Resource Management

Branch, Parks, Recreation & Sport Division, Alberta Tourism, Parks, Recreation and Culture for his

efforts with the Historical Resources assessment.

We also acknowledge the assistance provided by the following Alberta Environment individuals in

reviewing and providing valuable comments during the drafting of this final report: Garry Bucharski,

Saba Gnanakubar, Denis Magowan, Farrah McFadden, Bob Morrison, and Bob Sharp.

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1.0 INTRODUCTION

The purpose of this study was to assess and rank previously identified potential water storage sites and

diversion projects in Alberta, the information for which was compiled previously in Alberta

Environment’s (AENV) “2005 Project Inventory”.

This study was implemented by Alberta Environment (AENV) to address “reliable, quality water supplies

for a sustainable economy” as part of the provincial “Water for Life Strategy”.

The study was awarded to MPE Engineering Ltd. (MPE) in two phases: the first phase was awarded in

November 2006; the second in April 2007. MPE retained the services of Thurber Engineering Ltd. to

conduct the geotechnical assessment (see Appendix A) and Ursus Ecosystem Management Ltd. to

conduct the environmental and historical assessment (see Appendix B).

This report, the assessment tool worksheets, and supporting documents, are the culmination of work for

both phases.

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2.0 SCOPE OF WORK

The scope of work consisted of developing an assessment tool and a ranking system that is

understandable, sensible and defendable, and that can be utilized for all sites compiled in the 2005 AENV

inventory database (from the study entitled, “An Inventory of Potential Water Storage Sites and Diversion

Scenarios”, prepared for AENV by MPE Engineering Ltd., 2005). The assessment of each site was

comprised of two types of evaluation, one consisting of a numerical ranking of technical considerations,

and another consisting of a subjective evaluation. The assessments, as required by the Request for

Proposals (RFP), are on a scale of “major” basin. The “major” basins are ten “major” river basins

commonly used by AENV and are as defined in the inventory study (MPE, 2005):

• Athabasca

• Beaver

• Bow

• Hay

• Milk

• North Saskatchewan

• Oldman

• Peace / Slave

• Red Deer

• South Saskatchewan sub-basin

The reader should note this list of “major” basins differs from that in the Water Act, which considers the

Red Deer, Bow, Oldman and South Saskatchewan sub-basin as one major river basin, namely the South

Saskatchewan basin.

Other noteworthy requirements stated in the RFP:

• In the case of inventoried inter-basin diversion schemes (from one “major” basin to another), the

diversion components are excluded from assessment or ranking. These diversions remain in the

inventory and noted as inter-basin transfers, but are not assessed.

• The original cost estimates of projects are not escalated to current dollars.

• Potential sites that overlap existing reservoirs are not assessed.

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2.1 Specific Study Criteria

The following criteria are considered for assessment and scoring of the previously identified potential

water storage sites:

i) Evaluate undeveloped sites and intra-basin diversions only. ii) Inter-basin sites to be excluded from evaluation and ranking. iii) Suitability of geological site conditions. iv) Suitability of site hydrogeology. v) Flooded area – storage volume ratio. vi) Estimation of water supply and demand in the area served. vii) Aiding and balancing apportionment requirements. viii) Improving current efficiencies and benefits. ix) Improving conditions in basins with moratoriums. x) Current design conforming to present guidelines and legislation. xi) Site availability. xii) Improved water supply to 2050 for multi-use projects. xiii) Presence of protected or other significant land areas. xiv) Dam dimension and storage volume considerations. xv) General environmental impacts. xvi) Reservoir safety.

This assessment study does not provide recommendations in terms of developing sites, but it is

intended to:

• provide an objective as well as subjective evaluation of each inventoried storage site in a

basin-by-basin format,

• enable the user to decide whether a site or sites might warrant further investigation and

evaluation, and proceed to the next phase of addressing the “Water for Life” strategy by

updating existing studies and considering current design standards and criteria, environmental

issues and economic issues.

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The following subjective criteria are not “scored” but are commented on:

i) Historical documented costs. ii) Public opinion. iii) Project timelines. iv) Proximity issues. v) General environmental issues. vi) First Nations’ involvement. vii) Water supply-demand.

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3.0 DEVELOPMENT OF THE ASSESSMENT TOOL

The assessment tool was required to be: a) compatible with the existing inventory in a Microsoft Access©

database, b) flexible, c) updatable, and d) easy to use. Given these requirements, the Microsoft Excel©

spreadsheet software was selected as the platform for the assessment tool. Within this Excel© platform,

the assessment tool contains all previously identified inventoried sites, background data, all criteria and

their associated parameters and values. “Scores” based on the parameter values and score “weightings”

(which can be varied) are also included.

Refer to Appendix D for instructions and examples regarding use of the spreadsheet tool.

3.1 Assessment Tool Worksheets The assessment tool is comprised of 10 worksheets:

• 1 - Guideline

• 2 - Summary

• 3 – Supply-Demand

• 4 - Environment

• 5 - Site Availability

• 6 - Geotechnical

• 7 - Storage Efficiency

• 8 - Dam Safety

• 9 - Other Considerations, and

• 10 - Background.

The study assessment tool is not intended to be used to decide whether a site should be developed.

Rather, the assessment tool is intended to be used to compare sites within the same major basin and, in

conjunction with other factors important to the user, help decide whether a site warrants further

investigation.

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Worksheets 3 through 9 are the detailed assessment worksheets, which each address a group of related

specific criteria listed in Section 2.1. A brief summary of each of the ten worksheets is provided below.

Further details of these worksheets, their contents and explanations are found in Appendix C.

3.1.1 1 - Guideline

The Guideline worksheet contains an explanation of terms, assessment tool and limitations, and a

summary of what is contained in each of the other worksheets. The assessment tool user is encouraged to

read this worksheet before viewing the other worksheets and to use this worksheet as a reference while

using the tool.

3.1.2 2 - Summary

The Summary worksheet is a compilation of scores generated from worksheets 3 – 8, a compilation of

key considerations from worksheets 3 – 9, and comments which may be of general interest. It also

contains the calculated overall weighted score by which a site is compared to other sites within the same

major basin. It also contains an “A-B-C” grouping, where each site is assigned an “A”, “B” or “C” rating

based on the site’s overall weighted score, compared to other sites within the same major basin. The

purpose of this grouping is to provide the user with a simple way of identifying which sites are more

favourable for further investigation and evaluation. This worksheet also contains links to Google Earth©

images of each site to help the user gain a visual perspective of the site’s physical setting. Finally, a link

to the each site’s basin map is also provided, to help the user locate the site within its major basin and

relative to other identified sites in the basin.

3.1.3 3 – Supply-Demand

The Supply-Demand worksheet contains the various types of water supplies and water demands used in

determining the Supply-Demand scores, as well as the data to calculate net reservoir storage volume.

Ratios and associated scores for selected criteria are generated and presented here as well. The overall

Supply-Demand score is presented here as well as key considerations and general comments related to

supply and demand.

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3.1.4 4 - Environment

The Environment worksheet presents the scores of selected criteria, namely: a) “Within an

Environmentally Sensitive Area (ESA)”; b) Species at Risk”; c) “Natural Landscape”; d) “Historically

Significant Area”; and e) “Fish Bearing Stream”; as well as the overall weighted average Environment

score and key considerations specific to environmental issues.

3.1.5 5 - Site Availability

The Site Availability worksheet contains the description of human developments and named areas (such

as Reserves, Parks and Natural Areas) identified using sources such as Abacus Datagraphics

infrastructure information and Google Earth© imagery. A Site Availability score is determined using the

criteria described at the bottom of the worksheet. Key considerations specific to site availability issues

are also presented here.

3.1.6 6 - Geotechnical

The Geotechnical worksheet contains the description and scores of specific geotechnical criteria, namely:

a) borrow availability; b) foundation conditions; c) seepage issues; and d) reservoir stability. The overall

weighted average Geotechnical score and key considerations specific to geotechnical issues are presented

in this worksheet as well.

3.1.7 7 - Storage Efficiency

The Storage Efficiency worksheet contains the data used in determining ratios and associated scores of

the storage efficiency criteria as well as the scores for these criteria. The overall weighted average

Storage Efficiency score and key considerations specific to storage efficiency issues are also presented.

The year of the original study of the site and a general subjective comment on the cost of the project

construction is also provided in this worksheet.

3.1.8 8 - Dam Safety

The Dam Safety worksheet identifies existing human development or named site (such as Reserve, Park,

Natural Area) downstream of the site where human life, infrastructure and other development may be at

risk in case of dam failure. A Dam Safety score is determined from this information using the criteria

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describe at the bottom of this worksheet. Key considerations specific to dam safety issues are also

presented here.

3.1.9 9 - Other Considerations

The Other Considerations worksheet presents subjective comments related to specific issues, namely: a)

“improving current efficiencies and other benefits”; b) “known public opinion”; c) “project timeliness”;

and d) “First Nations involvement”. It should be acknowledged that First Nations are expected to be

consulted and involved with any proposed water storage site in Alberta. As well, key considerations

specific to these issues are highlighted on this worksheet.

3.1.10 10 - Background

The Background worksheet presents a summary of technical information of each site from the 2005

inventory database. This information is provided to help bring some context of the site to the user.

3.2 Assessment Criteria and Parameters

The assessment tool incorporates a weighted scoring system of selected criteria. The organization of the

scoring system is presented in Figure 1. The hierarchy is as follows:

1. Overall weighted score (weighted sum of the detail worksheet weighted average scores)

2. Detail sheet weighted average score (0-5, based on criteria scores on the detail worksheet)

3. Criterion score (based on value of the criterion parameter(s))

4. Criterion parameter(s)

The scoring system is arranged as follows:

• The criteria (identified in Section 2.1) are clustered into general categories, with each general

category assigned to a “detail worksheet”.

• Each criterion to be scored is assigned a parameter or parameters by which a site is measured.

• The parameters are assigned values from which the criterion is “scored”.

• The criteria scores are then assembled into a single “weighted average score” for each detail

worksheet.

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• The weighted average scores from the detail worksheets are then transferred to the summary

worksheet, where an “overall weighted score” is calculated.

The overall weighted score is the basis for an “A-B-C grouping”, which groups the sites into

approximately three equally sized categories, based on overall weighted scores, within a common

major river basin. This is discussed further in Section 3.2.4 Groupings.

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Figure 1: Scoring System Organization

Summary Worksheet

Overall Weighted Score

Detail Worksheet ‘A’

Weighted Score

Detail Worksheet ‘B’

Weighted Score

Detail Worksheet ‘C’

Weighted Score

Criterion ‘1’

Score

Criterion ‘3’

Score

Criterion ‘2’

Score

Parameter ‘a’

Parameter ‘c’

Parameter ‘b’

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3.2.1 Selection of Criteria and Parameters

The criteria requested by AENV are incorporated in the assessment tool as presented in Table 1 (for

scored criteria) and Table 2 (for subjective criteria). One additional scored criterion, “assist site demand”,

was added to provide an indication of the ability of the site to satisfy local (as opposed to basin-wide)

water demands.

The parameters used to describe and measure the scored criteria were selected and developed based on

several guiding principles including:

• Widely and commonly available data for a majority of the sites

• Sensible

• Defendable

• Straight forward, easy to understand

Table 1 presents the parameters used to represent the scored criteria.

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Table 1: Scored Criteria and Their Parameters

Criteria Parameters Parameter Descriptions Found in Worksheet

(i) Evaluate undeveloped sites and intra-basin diversions only

Not a criterion; only the storage component of a diversion scheme was assessed.

Not applicable Not applicable

(ii) Inter-basin sites to be excluded from evaluation and ranking

Not a criterion; only the storage component of a diversion scheme was assessed.

Not applicable Not applicable

(iii) Suitability of geological site conditions

Borrow Availability Foundation Conditions

Availability of Borrow (fill materials) Geologic Condition and Soil Types at the Site

5-Geotech

(iv) Suitability of site hydrogeology

Seepage Issues Reservoir Stability

Hydrogeologic Conditions at the Site Slope Stability and Susceptibility to Erosion

5-Geotech

(v) Flooded area – storage volume ratio

Storage Volume / Surface Area Ratio

Reservoir Storage Volume divided by Reservoir Surface Area 7-Storage Efficiency

(vi) Estimation of water supply and demand in the area served

Site Supply Site Demand

Average annual volume of water at the nearest Water Survey of Canada (WSC) longterm streamflow gauging station Total allocation of water in all WSC tertiary sub-basins downstream of the site and any apportionment or Instream Objectives requirements

3-Supply-Demand

(vii) Aiding and balancing apportionment requirements

Assist Apportionment Ratio

Lesser of Site Supply and Storage Volume, divided by annual apportionment volume

3-Supply-Demand

(viii) Improving current efficiencies and benefits

Supply / Demand Ratio Lesser of Site Supply, Site Demand, and Storage Volume, divided by Basin Demand

3-Supply-Demand

(ix) Improving conditions in basins with moratoriums


3-Supply-Demand

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Criteria Parameters Parameter Descriptions Found in Worksheet

(x) Current design conforming to present guidelines and legislation

Not used; almost all designs do not conform to current standards.

Because design guidelines and legislation continue to evolve, few if any site designs conform to current standards; including this information in the assessment tool would have limited value.

Not applicable

(xi) Site availability Reservoir and Dam Site Availability and Proximity Issues

Types and quantities of existing development within and near the reservoir and dam sites

6-Site Avail

(xii) Improved water supply to 2050 for multi-use projects


3-Supply-Demand

(xiii) Presence of protected or other significant land areas

Within an Environmentally Sensitive Area Native Landscape Historically Significant Area

Type, Level of Importance, and Area of Environmentally Significant Areas (ESA) and Alberta Protected Areas (APA) Type, Level of Importance, and Area of Native Landscapes Occurrence of archaeological, palaeontological, historical, and aboriginal traditional use sites

4-Environ

(xiv) Dam dimension and storage volume

Storage Volume / Dam Size Ratio

Reservoir Storage Volume divided by Volume of Dam Structure 7-Storage Efficiency

(xv) General environmental impacts Species at Risk Fish Bearing Stream

Species, occurrence, and vicinity of SARs Species, occurrence, and vicinity of fish

4-Environ

(xvi) Reservoir safety Storage Volume Dam Height Life Safety Socioeconomic, Financial and Environmental

Reservoir Storage Volume Maximum Dam Height Number and proximity of human presence downstream of site Type and proximity of development downstream of site

8-Dam Safety

(added) Assist site demand Supply / Site Demand Ratio

Lesser of Site Supply and Storage Volume, divided by site demand

3-Supply-Demand

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Table 2: Subjective Criteria and Their Worksheet Location

Criteria Criteria Descriptions Found in Worksheet

Historical documented costs Included only the cost of constructing dam, reservoir and ancillary structures, and the mitigation costs for existing development.

7-Storage Efficiency

Public opinion Where known, either current or at the time of the original report. 9-Other Considerations

Project Timeliness Indicated only in cases where the project would be expected to involve

a relatively lengthy process of consultation, design and approval, or a

relatively simple process.

9-Other Considerations

Proximity issues Identified existing development and named areas such as Reserves,

Parks, and Natural Areas. 6-Site Avail

General environmental issues Noted in addition to the Environment scoring criteria. 4-Environ

First Nations involvement It is acknowledged that for all sites, First Nations will be consulted and

involved. In this assessment, only known Reserves or specific First

Nations issues are identified.

9-Other Considerations

Water supply-demand Noted in addition to the Supply-Demand scoring criteria. 3-Supply-Demand

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3.2.2 Scores

Scores are based on either a “0-to-5” or a “1-to-5” system depending on the best-fit for the methodology

used in each worksheet. In all worksheets, higher scores relate to “more favourable” or “lower impact”

sites.

Supply-Demand and Storage Efficiency Worksheets: Within a major basin, the site with the highest

assigned value for a criterion is always assigned the most favourable score of “5”. All other sites in the

same basin are assigned a score relative to the site with the “5” score in the same major basin, with “1”

being the lowest score.

Environment Worksheet: Scores are assigned a value of “0-to-5” based on statistical analysis of relevant

data. Detailed discussion is provided in Appendix B.

Site Availability, Geotechnical and Dam Safety Worksheets: Scores of “1-to-5” are subjectively

determined based on a set of guideline rules as detailed in the footnotes of each worksheet. Geotechnical

assessment and scoring is discussed in detail in Appendix A.

3.2.3 Weightings

All scores are assigned “weightings” to provide some flexibility in the scoring system. These weightings

are assigned values from 1 to 10, depending on the perceived importance of criteria scores relative to each

other and detail worksheet scores relative to each other. Although the user has the capability of varying

the assigned weightings, the user is encouraged to be able to justify any such change before

implementation, primarily because the presented weightings are based on the opinions of experts.

3.2.4 Groupings

To help the user identify the most favourable sites at a broad scale, the overall weighted scores are

grouped by an A-B-C rating. The sites are assigned values of “A”, “B” or “C”, depending on the overall

weighted score, with “A” being most favourable and “C” being less favourable. These ratings are

currently set at arbitrary intervals of overall weighted scores to provide roughly a third of sites in each

grouping. The user has the capability of varying these intervals but is encouraged to be able to justify any

such change before implementation.

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3.3 Questionnaires

Information for the subjective criteria (found in all but the Guideline and Background worksheets) was

supplemented by AENV staff through a questionnaire developed by MPE Engineering Ltd. This

information was then summarized and made consistent to fit the cell size in the applicable worksheet and

be legible when printed. All information as originally provided by each of the respondents is saved in the

file archives on the enclosed disk.

3.4 Workshops

To validate the assessment tool, several senior MPE Engineering Ltd. personnel participated in three day-

long workshops to scrutinize the assessment tool and the results as well as add relevant personal

knowledge and subjective comments of the sites to the worksheets. The participants and their relevant

expertise were:

• Mike Breunig, P.Eng. (Water Resources and Dam/Reservoir Design, Alberta)

• Bruce Elson, P.Eng. (Water Resources and Dam/Reservoir Design, Southern Alberta)

• Barry Hurndall, P.Eng. (Dam Safety, Alberta)

• Harry Schoorlemmer, P.Eng. (Irrigation and Structures, Southern Alberta)

• Peter Stevens, P.Eng. (Hydrology, Water Allocations, Water Act, Alberta)

The workshops were preceded with each participant reviewing the latest draft version of the assessment

tool along with background information and assessment results of all sites within a few preselected major

basins. The workshops consisted of preliminary discussion of the latest assessment tool followed by an

evaluation and addition of subjective comments on a site-by-site basis. Once all information of all sites

within an entire major basin was considered, the results of the assessment tool were evaluated and the

assessment tool was modified as required.

Because (a) the time required to evaluate each site, in the workshops, was longer than had been

anticipated and (b) few modifications to the assessment tool were required by the third workshop, the

remaining unevaluated sites were completed using the following procedure: the sites not evaluated in the

workshops were evaluated collectively by two of the participants, the results of which were then reviewed

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individually by the other three participants. The conclusion of this procedure resulted in the final results

of the assessment tool.

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4.0 ASSESSMENT OF POTENTIAL STORAGE SITES

The 2005 inventory database included both storage sites and diversion projects. However, this

assessment is limited to storage sites only. If a diversion project included one or more storage sites, only

the storage sites are assessed. As a result, only parameter information for storage sites is compiled.

4.1 Definition of “On-stream” and “Off-stream”

All sites are classified as “on-stream”, “off-stream”, or “diversion”. In the 2005 inventory database,

designated storage sites were classified as on-stream or off-stream and those classifications are retained in

this assessment tool. However, some storage sites were classified as part of diversion projects, in the

2005 inventory database. For these sites, the classification was changed in this assessment tool to either

on-stream or off-stream using the following criterion:

> If the annual natural runoff volume was estimated to be greater than the reservoir volume, the

site is considered to be “on-stream”; otherwise, it is considered to be “off-stream”. This criterion

is adapted from a widely used definition which is more fully explained in the “Atlas of Alberta

Lakes” and other sources.

4.2 Information Sources and Information Quality

The various sources of information used in the assessment tool are found in the original 2005 inventory

database and are listed in Section 7.0 References.

The quality and age of information varies considerably from source to source and from site to site. The

detail of the original reports varied from a few sentences within a general report to several volumes of

detailed description and assessment. The level of design varied from a location sketched on a map to

detailed designs. Also, the familiarity with the sites varied from person to person. This variation in

information quality made consistency of site assessments difficult and limited the results of the study to

an assessment tool for the purposes of identifying obvious issues and project feasibility relative to others

within the same major basin.

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4.3 Assessed Sites

Of the total of 238 sites identified in the original 2005 inventory database, 59 sites are considered to be

diversion projects and the remaining 179 sites are considered on-stream or off-stream storage sites and are

assessed.

During the assessment process, three other on-stream sites were “discovered” in the available reports

from the 2005 inventory study, namely,

• # 239, “Smoky – 11 miles downstream of Wapiti and Simonette Rivers”, Peace River basin;

• # 240, “Lesser Slave Lake – Hydro”, Athabasca basin; and

• # 241, “Baptiste River – Sunchild Storage Area”, North Saskatchewan basin.

Information is limited for these sites; however, they were added to the list of 179 storage sites, for a total

of 182 assessed sites.

Of the 182 assessed sites, the scores of 92 sites are reduced due to insufficient information. The vast

majority of missing information is the reservoir surface area and/or dam height. Although beyond the

scope of this study, this missing information could be estimated using existing digital elevation models

and contour maps, the result of which would significantly improve the consistency of scores among the

sites within each major basin.

The assessment tool is flexible and can produce varying results depending on the importance (weighting)

each criterion is given by the user. As such, only a general summary of the results is presented here.

Detailed assessment results are presented by major river basin in Appendix E.

Within this context, however, the presented scores, weightings and groupings are the result of efforts by

individuals with considerable water management experience. It is recommended that any changes made

to the presented values are defendable and any changes to the information are reliable.

ENGINEERING LTD.


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The enclosed disk (in Appendix F) includes the entire list of sites within the assessment tool, along with

Google Earth© images of each site. The disk also contains the 2005 Inventory Database, the river basin

maps and other pertinent background information.

ENGINEERING LTD.


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5.0 DISCUSSION

This assessment tool should prove to be valuable in improving the management of Alberta’s water

resources, particularly for supply management, as the demand for water grows and climate change

impacts occur in the years ahead.

5.1 Limitations and Data Gaps

While the assessment tool as presented is useful in terms of its flexibility and ability to aid the user in

determining which sites may warrant further investigation, there are also limitations to its usefulness,

some of which are described below.

5.1.1 Data

The assessment of any site is limited by the type, availability, quality, age and accuracy of the data used

to assess the site. The assessment tool is limited by the data which were readily available at the time of

this study. Quality of data varies significantly from site to site and from one type of data to another. This

issue alone imposes significant challenges with comparison of sites as “apples-to-apples”. Time and

resources were also factors in determining which data were eventually used in this assessment tool

considering the level of this study.

Available reports for sites date back to the 1950’s. These earlier reports contain designs which are not

according to current technical standards (such as the 2007 Canadian Dam Safety Guidelines); did not

consider environmental issues or other water users; generally were identified for a specific single purpose

(such as hydroelectric generation or irrigation); and benefit and cost data are significantly out-of-date. As

such, only the most basic data (such as location and maximum reservoir size) from those reports are

pertinent today.

This study assessment tool is not intended to be used to decide whether a site should be developed.

Rather, it is to be used to compare sites within the same major basin relative to each other, and in

conjunction with other factors important to the user, to help decide whether a site warrants further

investigation.

ENGINEERING LTD.


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5.1.2 Methodology

The methodology for this assessment tool was derived by attempting to balance the requirements of being

compatible with the existing inventory in a Microsoft Access© database (completed in 2005), flexible,

updatable, and easy to use; and within the allotted time and resources, while providing useful and

meaningful results from a myriad of data. As such, this assessment tool is limited in its complexity (such

as not considering some criteria) and flexibility (such as no “data sorting”).

5.1.3 River Basins

All meaningful comparisons of sites are very dependent on scale and selected criteria. For instance, how

can a potential on-stream site on the Peace River be meaningfully compared to an off-stream site on a

coulee in southern Alberta? For this reason, sites are segregated by major river basin and all scoring and

ratings are based on data relative to other sites common to the same river basin. As a result, a score of

say, 100 in one basin is not equivalent to a score of 100 in another basin. Therefore:

5.2 Next Steps for Site Investigations and Evaluation

After using the assessment tool, the user may decide that a site or sites warrant further investigation and

evaluation for potential construction. Some of the issues and “next steps” to which the user can expect to

expend effort are as follows.

• Design Requirements and Criteria: compile specific needs and criteria for the project, including water

demands (quantities, timing, locations, distribution systems, restrictions including water conservation

objectives, senior water licence priorities).

• Research and data collection of site conditions: collect physical, historical, palaeontological,

biological and environmental data of site(s) and surrounding areas.

Comparing scores are only meaningful and relevant with sites common to a major river basin.

ENGINEERING LTD.


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• Public and First Nations consultation: begin dialogue with stakeholders early in process to cultivate

working relationships and trust; discuss expectations and concerns from all entities and identify issues

that need resolution.

• Alternatives: identify potential solutions which satisfy identified requirements, and produce feasibility

document(s).

• Design: select preferred alternative(s) and provide progressively detailed designs which comply with

current legal, technical, environmental and social legislation and guidelines.

• Approvals: provide required information to various levels of government to obtain approvals from the

various jurisdictions.

• Public and First Nations consultation: continue with open dialogue with stakeholders throughout the

process to create the most positive outcome possible.

• Mitigation: identify, evaluate and provide mitigation measures where needed.

The time required to complete these “next steps” will vary depending on project size, location and

complexity of issues. However, based on existing water storage projects, project proponents can expect

the time required for the simpler projects to be about two years. The more complex projects can take 10

years or more from start to completion.

ENGINEERING LTD.


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6.0 RECOMMENDATIONS

It is recommended that the user be fully aware of the flexibility as well as the limitations of this

assessment tool. These are described elsewhere in this report and in the Guideline worksheet of the

assessment tool.

The assessment tool is developed such that the criteria and scoring are on the scale of major basin.

Therefore, the score of say 100 for a site in one major basin is not necessarily the same as a score of 100

for a site in another major basin. It is recommended that comparisons of sites be limited only to those

sites within a common major basin.

This assessment tool is intended to be used as an initial overall assessment of sites within a common

major basin. It is recommended that, as a result of using this assessment tool, if a site(s) appears to be

favourable for the intended purpose(s), this site(s) undergoes further investigation and evaluation to verify

the initial findings.

Several aspects of this assessment tool can be improved and are identified as follows:

Infill missing data for scoring purposes:

• would improve completeness of scoring of sites, better able to compare sites,

• vast majority of missing data for scoring purposes is technical in nature, such as reservoir surface

area and dam height; these data are for the most part, relatively easy to obtain from graphs of

existing drawings or estimate from contour maps.

Modify Supply-Demand scoring by accounting for existing storage in a basin (primarily in SSRB):

• would more accurately describe “true” storage requirements,

• may have minor impact on overall score,

• would identify and locate existing storage sites with at least 10,000 dam3 storage, subtract these

volumes from demands by Water Survey of Canada tertiary sub-basin.

ENGINEERING LTD.


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Refine Supply-Demand supply and demand estimates:

• would more accurately describe “true” site supply and site demand values,

• would provide more accurate scoring,

• for supply numbers, need to determine drainage areas of each site, then use ratio of site and

gauging station drainage areas to estimate site supply,

• for demand numbers, need to determine locations of water licences by site drainage areas.

Refine techniques quantifying Environmental criteria:

• incorporate reservoir surface area for criteria using buffer zones to determine scores, would

improve estimate of impact on these scored criteria, particularly of large reservoirs,

• for fish bearing streams, use Alberta Code of Practice Stream Rankings for stream reaches rather

than buffer zones,

• would provide more reliable scoring,

• would need to digitize reservoir areas and develop buffer zones accordingly.

Edit database to more accurately categorize sites as On-stream, Off-stream, or Diversion:

• many sites are currently identified as Diversion sites because they were associated with a

diversion scheme; however these sites are obviously considered Off-stream or On-stream,

• important to correctly identify these sites for the intended (public) users.

ENGINEERING LTD.


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7.0 REFERENCES

• Abacus Datagraphics

• Alberta Environment, January 2007: Compilation of Active Surface Water Allocations

• Alberta Environment, January 2007: Compilation of Instream Objectives

• Atlas of Alberta Lakes

• Environment Canada, Water Survey of Canada streamflow data accessed from website:

http://www.wsc.ec.gc.ca/hydat/H2O/index_e.cfm?cname=main_e.cfm

• Google Earth©

• Government of Alberta NTS series topographical maps of Alberta

• International Joint Commission International Waters Apportionment Agreement

• Mackenzie River Basin Transboundary Waters Master Agreement

• MPE Engineering Ltd., 2005: “An Inventory of Potential Water Storage Sites and Diversion

Scenarios”, prepared for AENV.

• PFRA evaporation map website: http://www.agr.gc.ca/pfra/gis/maps/print/evap_e.pdf

• PFRA precipitation map website: http://www.agr.gc.ca/pfra/gis/maps/print/precip_e.pdf

• PPWB Apportionment Agreement


APPENDIX A

Geotechnical Assessment

Thurber Engineering Ltd.

January 31, 2008 File: 19-2252-10 MPE Engineering Ltd. Suite 260, East Atrium 2635 - 37 Avenue NE Calgary, AB T1Y 5Z6 Attention: Mr. Harry Schoorlemmer, P.Eng.

ASSESSMENT OF POTENTIAL WATER STORAGE SITES

GEOTECHNICAL DESK STUDY - PHASE 2

Dear Sir:

This letter report presents the methodology for a desk study conducted to assess and rank a number of potential dam sites throughout Alberta from a geotechnical suitability standpoint. The work was conducted in two phases, with the initial phase of work completed at the end of February 2007 and reported in a letter dated March 6, and the remaining sites assessed in July and August 2007. The spreadsheet containing ranking information and comments will be transmitted by email.

The Alberta Environment terms of reference for this project were forwarded by email by MPE Engineering on October 11, 2006. The scope of work was outlined in our proposal of October 16, 2006, and modified in the submission from MPE to Alberta Environment. An Agreement for Services was received from MPE on January 25, 2007, with approval to proceed with this second phase of work from MPE on April 20, 2007.

This letter and the associated data are provided subject to the attached Statement of General Conditions. As noted above, the work was conducted for Alberta Environment through MPE, and for the purposes of the Statement of General Conditions, Alberta Environment will also be considered as the Client. Alberta Environment is authorised to provide copies of the report and the associated data to other Government departments and Watershed Planning and Advisory Councils.

1. INTRODUCTION

MPE Engineering Ltd. is helping Alberta Environment refine an inventory of approximately 238 potential reservoir sites and diversions in Alberta by assessing each site for a number of characteristics. Thurber is assisting MPE by providing input on geotechnical issues such as anticipated borrow availability, foundation conditions, seepage issues and reservoir stability.

2. METHODOLOGY

2.1 Information

MPE provided Thurber with the following information:

• PDF copies of reports on a number of the potential dam sites.

• A spreadsheet listing the potential dam sites, including the locations.

• A ranking spreadsheet with columns allocated for ranking borrow, foundation conditions, seepage issues and reservoir stability, and with room for comments.

• A copy of the 2005 database of potential dam sites.

The co-ordinates of the various dam sites were input into a waypoint file and used with a database of public domain geological mapping information and satellite imagery. In a number of cases, the supplied co-ordinates were found to be inaccurate. Where a report was available with maps or descriptions, the dam site locations were adjusted. Where there was insufficient information to identify the

Client: MPE Engineering Ltd. Date: January 31, 2008 File No. 19-2252-10 Page 2 of 10 E file: H:\19\2252\10 - AENV Dam Site Assessments\AENV Dam site assessments phase 2 final.doc

proposed dam site location, and in the absence of any geotechnical information in the report, no ranking was attempted.

The information used to assess the various categories varied from relying only on published geological mapping where there was no report, or a report with no geotechnical information, to concept design studies with geotechnical investigation. All the reports were skimmed briefly to glean useful information, and compared with the information available from the geological maps. In some instances, Thurber has experience with the geotechnical conditions in an area, which we have included in our assessments.

2.2 Ranking

The spreadsheet supplied by MPE contained columns for the four broad geotechnical categories that were identified by Thurber and MPE during development of the proposal. Ranking was done subjectively on a scale of 1 to 5, with 1 being poor conditions, 3 being average and 5 being best conditions. Examples of what the various ranks might indicate are provided in the sections below, though it should be remembered that the ranking is subjective, and there are likely to be a number of factors within each category which, taken together, contribute to the score. Ranking was done on a Province-wide basis, rather than basin-by-basin to make it easier to apply consistent ranking. Review of maps and reports and ranking was conducted by Mr. Simon Cullum-Kenyon, P.Eng. who has over 15 years of experience in geotechnical engineering, with the ranking results and methodology reviewed by Dr. John Sobkowicz, P.Eng., a recognised expert in geotechnical engineering for dams. The categories are outlined in the following sections, together with notes on what source data was used.

2.2.1 Borrow Availability

This category indicates anticipated borrow availability. Unless otherwise indicated in a report, it has been assumed that there is a requirement for both granular and impermeable borrow suitable for construction of an earth dam. In some instances, concept designs included specific mention of a rock fill dam, for example.

The primary data sources for this category were information in supplied reports and available surficial geological maps. Suitability of rip rap sources was assessed


based on anticipated cover and mapped rock types. Where there were discrepancies between the information on the maps and that contained in the reports, we sided with the data which appeared more reliable. In some instances, there were mapped sections available, indicating relative thicknesses of various materials. The suitability of materials as borrow has been interpreted from the reports and maps, and should be regarded as tentative at best. Factors that might impact borrow source suitability that are not readily apparent from geological mapping include thickness and continuity of deposits, whether the deposit is above the water table, or in the case of impervious borrow, the moisture content of the deposit. None of these factors has been assessed at this level of study.

Rock for rip rap typically needs to be durable, hard and with sufficiently widely spaced joints that large enough blocks are produced when the rock is blasted. There are only a few places where such rock is present, predominantly within the Rockies and locally within the Foothills. In most cases away from the Foothills, it has been assumed that there is no suitable local supply of rip rap.

Ranking was done subjectively, with a ranking of between 1 and 5. A rough scale for the various ranks is shown below:

5 - Supplies of impervious and granular borrow and rip rap in the local area.

3 - Average Alberta conditions i.e. impervious borrow available locally, granular borrow might need to be trucked in, no local supply of rip rap.

1 - Most or all borrow materials are not available in the local area.

2.2.2 Foundation Conditions

This category indicates anticipated foundation conditions and identifies problematic materials, such as weak soils or bentonite beds. This is a difficult category to assess without specific information in a report, as poor foundation conditions can be very localised, and hence not portrayed on regional scale geological maps. Where report information was not available, assessment was based on the presence of bentonite beds noted from the bedrock mapping, or the presence of suspected weak soils such as organic soils or silty and clayey alluvial soils.



5 - Competent bedrock at shallow depth, no bentonite seams or weak layers identified or mapped locally. Narrow river valley with little or no fine-grained alluvial deposits.

3 - Average Alberta conditions i.e. rock or till at shallow or moderate depth, no bentonite seams identified or mapped locally. Some fine-grained alluvial deposits in a wider river valley. Possibility of buried valley with weaker soils.

1 - Underlying rock is known to include bentonite seams, instability noted in valley walls, wide floodplain with a low energy, meandering river or a poorly drained area with lakes and bogs, soft soils known in the foundation.

2.2.3 Seepage Issues

This category indicates anticipated seepage issues, primarily at the dam site, either in the foundation or abutments, but includes detrimental seepage occurring elsewhere as well.

Data for ranking this category comes from previous reports and surficial geology mapping. Mapped conditions that were taken to indicate potential seepage problems include the presence of buried or mapped surface melt water channels, as well as surface or near surface granular materials, including talus and landslide deposits. Mention of springs in the valley walls upstream or downstream of the proposed dam site was taken as a sign that seepage in the abutment was likely to be a problem. Assessing the importance of seepage issues is difficult at this level of study, and scoring should be regarded with caution.


5 - Low permeability rock or till in foundation and abutments, requiring only limited treatment.


3 - Average Alberta conditions i.e. some permeable materials at relatively shallow depth requiring a seepage cut off or placement of an impermeable blanket; some seepage control required in abutments.

1 - Significant depth of permeable materials requiring substantial cut off effort, wells, cut off blanket and grouting. Cut off required in abutments and locally around reservoir. Cut off expected to be extensive or even beyond the limit of conventionally available local equipment (i.e., would require specialised equipment be brought in from out of Province, e.g., a Hydromill for use in bouldery soils > 10 m depth).

2.2.4 Reservoir Integrity

This category assesses the risk of slope instability and erosion problems around the reservoir or at the dam site. Included in this category is an assessment of reservoir shoreline erosion problems, i.e., erosion susceptibility due to likely soil types exposed along the reservoir. Lacustrine silts and sands were assumed to be most susceptible to erosion, and attracted lower ratings, though their presence was not considered as significant a factor as the presence of a landslide, for example.

Indicators for lower reservoir integrity ratings included mapped or noted occurrence of landslides around the reservoir, landslides elsewhere in the local area, and the presence of bentonite seams in rock potentially exposed in the abutments. In addition, consideration was given to whether seepage might trigger instability in the abutments or downstream of the dam.

Satellite imagery from Google Earth and other public domain sources for identification of existing landslide occurrence was found to be of little use due to the relatively low resolution of public domain products (at the time the ranking was conducted).


5 - No landslides noted either at the site or in the local area. Landslides considered unlikely because of topography and no known weak materials and/or seepage issues.


3 - Average Alberta conditions i.e. some minor (surficial) slides either active or anticipated, around the reservoir or downstream. Minor shoreline erosion problems due to localised presence of lacustrine silt and sand.

1 - Mapped or noted landslide problems at the dam site or around the reservoir, e.g. evidence of active rockslide.

2.3 Total Geotechnical Score

Each of the category rankings is multiplied by a weighting factor, summed, and then divided by the sum of the weighting factors to come up with an overall score. Weightings for the borrow and reservoir integrity categories have been adjusted downwards so that the overall score better reflects dam feasibility. The weighting used is summarised below:

Category Weighting Borrow Availability 6

Foundation Conditions 10 Seepage Issues 10

Reservoir Integrity 4

Using higher weightings for borrow and reservoir integrity could result in an overall geotechnical score that would better reflect cost rather than feasibility alone. For some sites, higher scores for one or more factors have increased the total score where a poor score in one factor should probably carry more weight. This issue is discussed further in Section 3.

2.4 Notes

Adjacent to each of the ranking columns is a column for notes on that category, which we have used to summarise relevant issues. After the column with the total geotechnical score there is a summary notes column which contains important comments from each of the previous notes columns.

In addition to the notes, a data quality column has been added at the end to provide an indication of the level of information available to assess the various rankings. This information is designed to provide an indication of the reliability of


the rankings. There is further discussion of the issues posed by differing levels of investigation information in the following section. Data quality was ranked subjectively according to the following scale:

1 – Bedrock and surficial mapping only (no previous reports)

3 – Concept design report with summary geological information, comments on borrow availability.

5 – Preliminary design or comprehensive concept design with one or more phases of test hole drilling.

A column has also been added for the minimum category score for each site. This number should be taken together with the overall geotechnical score when considering a site, as it will indicate if there is a low score in one of the geotechnical categories (borrow, foundation, seepage, reservoir) that could impact feasibility.

3. DISCUSSION

There are very significant variations in the quality of data available to conduct the ranking process, varying from bedrock geology and limited or no surficial mapping, to preliminary design reports with extensive geological and geotechnical information. We have tried to capture this variation in the data quality column appended to the ranking spreadsheet. For sites with good data, there is fair confidence that the rankings represent anticipated conditions at the site. There is a risk that investigations at the site have not identified conditions that could limit feasibility. For sites with no previous report geotechnical information, the level of risk that conditions are not accurately identified is significantly higher. The practical implication of this is that poor sites with little data might appear ‘average’ and hence more feasible than other sites with better investigation data that were ranked ‘below average’. The data quality should be regarded as inversely proportional to the spread or ‘standard deviation’ of the total geotechnical score for a particular site.

The different factors assessed can have a variable influence on the feasibility and cost of constructing a dam. For example, borrow availability is less important for smaller earthfill dams and concrete dams, but very important for large earthfill


dams with shallow slopes where total borrow quantities are larger. Foundation conditions are typically more important for larger structures because of heavier loading and higher consequences of failure. Severe seepage issues are likely to be onerous in relation to total project costs for a small dam with limited storage, but could perhaps be dealt with in a larger project with significant storage and larger budgets.

The total geotechnical score can down-play issues that could prevent a project from going ahead, particularly where one factor is poor while others are good. An earthfill dam that has good foundation conditions, no seepage issues and no reservoir or slope stability concerns might not go ahead if there was no impervious borrow, but could get an overall score of 4. It will be important to check comments for “project-killer” issues, particularly where a project is being considered for further work. The minimum geotechnical score column taken in conjunction with the overall score will help indicate sites where one factor is poor while others are good.

The limited time/budget available to conduct the reviews means that some of the more subtle indications in reports or on maps may have been missed. This exercise is designed to be a preliminary ranking, with less than 1 hour of engineering time spent on each site. The results should be treated with caution in accordance with the limited effort applied to each site and the limited information available. Some sites may turn out to have more or less favourable conditions than those indicated in the rankings.


THURBER ENGINEERING LTD.

STATEMENT OF GENERAL CONDITIONS

Nature and Exactness of Soil and Contaminant Description: Classification and identification of soils, rocks, geological units, contaminant materials and quantities have been based on investigations performed in accordance with the standards set out in Paragraph 1. Classification and identification of these factors are judgmental in nature. Comprehensive sampling and testing programs implemented with the appropriate equipment by experienced personnel, may fail to locate some conditions. All investigations utilizing the standards of Paragraph 1 will involve an inherent risk that some conditions will not be detected and all documents or records summarizing such investigations will be based on assumptions of what exists between the actual points sampled. Actual conditions may vary significantly between the points investigated and the Client and all other persons making use of such documents or records with our express written consent should be aware of this risk and this report is delivered on the express condition that such risk is accepted by the Client and such other persons. Some conditions are subject to change over time and those making use of the Report should be aware of this possibility and understand that the Report only presents the conditions at the sampled points at the time of sampling. Where special concerns exist, or the Client has special considerations or requirements, the Client should disclose them so that additional or special investigations may be undertaken which would not otherwise be within the scope of investigations made for the purposes of the Report.

Reliance on Provided Information: The evaluation and conclusions contained in the Report have been prepared on the basis of conditions in evidence at the time of site inspections and on the basis of information provided to us. We have relied in good faith upon representations, information and instructions provided by the Client and others concerning the site. Accordingly, we cannot accept responsibility for any deficiency, misstatement or inaccuracy contained in the Report as a result of misstatements, omissions, misrepresentations, or fraudulent acts of the Client or other persons providing information relied on by us. We are entitled to rely on such representations, information and instructions and are not required to carry out investigations to determine the truth or accuracy of such representations, information and instructions.

a)

b)

1. STANDARD OF CARE

This study and Report have been prepared in accordance with generally accepted engineering or environmental consulting practices in this area. No other warranty, expressed or implied, is made.

2. COMPLETE REPORT

All documents, records, data and files, whether electronic or otherwise, generated as part of this assignment are a part of the Report which is of a summary nature and is not intended to stand alone without reference to the instructions given to us by the Client, communications between us and the Client, and to any other reports, writings, proposals or documents prepared by us for the Client relative to the specific site described herein, all of which constitute the Report.

IN ORDER TO PROPERLY UNDERSTAND THE SUGGESTIONS, RECOMMENDATIONS AND OPINIONS EXPRESSED HEREIN, REFERENCE MUST BE MADE TO THE WHOLE OF THE REPORT. WE CANNOT BE RESPONSIBLE FOR USE BY ANY PARTY OF PORTIONS OF THE REPORT WITHOUT REFERENCE TO THE WHOLE REPORT.

3. BASIS OF REPORT

The Report has been prepared for the specific site, development, design objectives and purposes that were described to us by the Client. The applicability and reliability of any of the findings, recommendations, suggestions, or opinions expressed in the document, subject to the limitations provided herein, are only valid to the extent that this Report expressly addresses proposed development, design objectives and purposes, and then only to the extent there has been no material alteration to or variation from any of the said descriptions provided to us unless we are specifically requested by the Client to review and revise the Report in light of such alteration or variation or to consider such representations, information and instructions.

4. USE OF THE REPORT

The information and opinions expressed in the Report, or any document forming part of the Report, are for the sole benefit of the Client. NO OTHER PARTY MAY USE OR RELY UPON THE REPORT OR ANY PORTION THEREOF WITHOUT OUR WRITTEN CONSENT AND SUCH USE SHALL BE ON SUCH TERMS AND CONDITIONS AS WE MAY EXPRESSLY APPROVE. The contents of the Report remain our copyright property. The Client may not give, lend or, sell the Report, or otherwise make the Report, or any portion thereof, available to any person without our prior written permission. Any use which a third party makes of the Report, are the sole responsibility of such third parties. Unless expressly permitted by us, no person other than the Client is entitled to rely on this Report. We accept no responsibility whatsoever for damages suffered by any third party resulting from use of the Report without our express written permission.

5. INTERPRETATION OF THE REPORT

(see over . . . . )

THURBER ENGINEERING LTD.

Design Services: The Report may form part of the design and construction documents for information purposes even though it may have been issued prior to the final design being completed. We should be retained to review the final design, project plans and documents prior to construction to confirm that they are consistent with the intent of the Report. Any differences that may exist between the report recommendations and the final design detailed in the contract documents should be reported to us immediately so that we can address potential conflicts.

Construction Services: During construction we must be retained to provide field reviews. Field reviews consist of performing sufficient and timely observations of encountered conditions to confirm and document that the site conditions do not materially differ from those interpreted conditions considered in the preparation of the report. Adequate field reviews are necessary for Thurber to provide letters of assurance, in accordance with the requirements of many regulatory authorities.

c)

6. RISK LIMITATION

Geotechnical engineering and environmental consulting projects often have the potential to encounter pollutants or hazardous substances and the potential to cause an accidental release of those substances. In consideration of the provision of the services by us, which are for the Client's benefit, the Client agrees to hold harmless and to indemnify and defend us and our directors, officers, servants, agents, employees, workmen and contractors (hereinafter referred to as the "Company") from and against any and all claims, losses, damages, demands, disputes, liability and legal investigative costs of defence, whether for personal injury including death, or any other loss whatsoever, regardless of any action or omission on the part of the Company, that result from an accidental release of pollutants or hazardous substances occurring as a result of carrying out this Project. This indemnification shall extend to all Claims brought or threatened against the Company under any federal or provincial statute as a result of conducting work on this Project. In addition to the above indemnification, the Client further agrees not to bring any claims against the Company in connection with any of the aforementioned causes.

7. SERVICES OF SUBCONSULTANTS AND CONTRACTORS

The conduct of engineering and environmental studies frequently requires hiring the services of individuals and companies with special expertise and/or services which we do not provide. We may arrange the hiring of these services as a convenience to our Clients. As these services are for the Client’s benefit, the Client agrees to hold the Company harmless and to indemnify and defend us from and against all claims arising through such hirings to the extent that the Client would incur had he hired those services directly. This includes responsibility for payment for services rendered and pursuit of damages for errors, omissions or negligence by those parties in carrying out their work. In particular, these conditions apply to the use of drilling, excavation and laboratory testing services.

8. CONTROL OF WORK AND JOBSITE SAFETY

We are responsible only for the activities of our employees on the jobsite. The presence of our personnel on the site shall not be construed in any way to relieve the Client or any contractors on site from their responsibilities for site safety. The Client acknowledges that he, his representatives, contractors or others retain control of the site and that we never occupy a position of control of the site. The Client undertakes to inform us of all hazardous conditions, or other relevant conditions of which the Client is aware. The Client also recognizes that our activities may uncover previously unknown hazardous conditions or materials and that such a discovery may result in the necessity to undertake emergency procedures to protect our employees as well as the public at large and the environment in general. These procedures may well involve additional costs outside of any budgets previously agreed to. The Client agrees to pay us for any expenses incurred as the result of such discoveries and to compensate us through payment of additional fees and expenses for time spent by us to deal with the consequences of such discoveries. The Client also acknowledges that in some cases the discovery of hazardous conditions and materials will require that certain regulatory bodies be informed and the Client agrees that notification to such bodies by us will not be a cause of action or dispute.

9. INDEPENDENT JUDGEMENTS OF CLIENT

The information, interpretations and conclusions in the Report are based on our interpretation of conditions revealed through limited investigation conducted within a defined scope of services. We cannot accept responsibility for independent conclusions, interpretations, interpolations and/or decisions of the Client, or others who may come into possession of the Report, or any part thereof, which may be based on information contained in the Report. This restriction of liability includes but is not limited to decisions made to develop, purchase or sell land.

INTERPRETATION OF THE REPORT (continued . . . . )

d)

SGC20050425


APPENDIX B

Environmental & Historical Resources Assessment

Ursus Ecosystem Management Ltd.

Ursus Ecosystem Management Ltd. Page 1

Dec. 19, 2007

Alberta Environment Assessment of Potential Water Storage Sites and Diversion Scenarios Environmental and Historical Assessment 1. Objectives

The objectives of this aspect of the Project were to:

• Assess presence and amount of Environmentally Significant Areas (ESA) within project site areas.

• Assess presence of Government of Alberta Protected Areas (APA) within project site areas.

• Classify and quantify “natural landscape” within project site areas. • Determine presence of fish bearing water bodies within project site

areas. • Determine presence of historically significant areas within project site

areas. • Determine presence of a disproportionate number of vertebrate

species-at-risk (SAR) within project site areas. • Determine relative score for each of the five environmental criteria.

2. Methods Spatial, digital datasets were acquired through Alberta Government Resource Data Division, Fish and Wildlife and PFRA for use in a geographic information system (GIS). To help quantify the various environmental factors for the proposed project sites, four circular buffers were created around the project coordinates measuring one, ten, one hundred and one thousand hectares respectively. An overlay process for the ESA’s and APA’s was done to calculate the area of each government designation if within the various buffers. The number of ESA’s or APA’s were not recorded. Table 1 outlines the classification rules for rating the prospective sites relative to one another. The rating was based on the % of each buffer that was occupied by an ESA or APA. The “Significance” columns in the spreadsheet refers to the level of importance i.e. 1=International, 2=National and 3=provincial. Alberta Protected Areas were processed after the ESA’s and considered secondary to the ESA’s in importance. Level 3 rules were used for scoring the APA’s as the protected areas within


affected buffers were of provincial designation. The score changed only if the classification was lower than that of the ESA. Ten project sites were lowered by the APA’s, twenty eight were present within the project site 1000 hectare buffers. The occurrence of natural landscape was quantified using the Generalized Landcover for the Canadian Prairies dataset as classified by the PFRA. This data was derived from Landsat 7 imagery and consists of eight landcover classes. Natural landcover types were differentiated from non-natural. and used to determine area of natural landcover within a 1000 hectare buffer around each site. The area totals within the buffers were compared and scored from 0 to 5 based on relative abundance. (see Table 2).

Historically significant areas were assessed and summarized by John D. Brandon of Land Use Planning Section, Heritage Resource Management Branch, Parks, Recreation & Sport Division, Alberta Tourism, Parks, Recreation and Culture. Mr. Brandon used the “Listing of Significant Sites and Areas”, the main tool used for small scale oil and gas regulation. It contains all the significant historical sites including archaeological, palaeontological, historical and aboriginal traditional use sites, as well as areas with high potential for archaeological and palaeontological resources. The number of sensitive or potentially sensitive areas around each site was counted and scored from 0 to 5 based on relative abundance. (see Table 3).

The presence of Species at Risk (SAR) and the presence of fish-bearing water bodies were assessed using data and GIS analysis provided by Alberta Fish and Wildlife. The government datasets are the most comprehensive in the province and are comprised of observations reported to Fish and Wildlife by individuals and organizations over approximately the past 30 years. The Fish and Wildlife data has limitations. Because it is not stratified and no survey design was employed in it’s acquisition,, it is not comprehensive or uniform across the province. The data tends to be biased by how and where it was reported and the precision of its location varies with the nature of the report. The largest potential error exists where a highly productive area has no observations, such as in a remote part of the province.

SAR were assessed using the number of animals reported and their conservation status. Species were considered at risk if they had a designation of “at risk”, “may be at risk” or “sensitive”. Scoring the project sites for SAR and fish bearing water bodies were done based on the number of observations and the number of individual animals observed as outlined in Table 4 and Table 5 respectively.


3. Criteria Weighting The five environmental criteria used to assess the potential of sites for water storage

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