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Dear Dale

As I had not received any response from the City, following a meeting with you and Cory several weeks

back, I prepared a detailed letter to Cory outlining the apparent lack of consideration given to flood risk

in the recent land use decision made with regards to properties located on the Salmon River delta. The

Citys management of development based on flood hazard using a flood elevation is an outdated

approach and would not likely meet an accepted standard of professional practice, as it does it provide

appropriate safeguards for the public, the environment and other stakeholders. Several areas around

the world, including most of Europe and a significant part on North America, have recognized this and

now manage flood issues based on risk.

APEGBC has a task force in-place that has just completed the first draft of a Guideline for profession

practice relating to flood hazard and risk assessment. This guideline provides guidance to both

professionals and approving authorities. It is expected to be released by March 2011.

As you are aware from my meeting with you and Cory and from the attached letter, it is my professional

opinion that the City has made a land use decision, regarding an obvious flood prone area, without

acknowledging or requesting any information with respect to the flood risk. The public is for the largestpart not aware of the potential flood risks associated with the existing and potentially proposed

development on the subject property. In addition, based on the comments made by council members

during the public hearings, they too are not aware of the flood risks associated with development on the

active flood plain.

In speaking with the developer, Mr. Alan Lee, P.Eng. last week he has flatly refused to release

topographic information for the subject property claiming the property and information are private.

Personally, I have never been refused access to topographic information and professionally I see no

reason to refuse this request as such information would be crucial in the assessment of the flood hazard

and risks.

The presence of the existing fi ll on the subject property may represent a significant flood risk to the

adjacent landowners and infrastructure, including the CP Rail bridge and embankment. However, I am

not aware of any flood risk assessment that has been done on the Salmon River delta. I would like to

know if the City and/or the Developer will acknowledge that there are presently unqualified and un-

quantified flood risks associated with the subject site in its present state?

Also, will the City and/or Developer take action to assess the magnitude of the flood hazard and

associated risks and whether the risks are acceptable to the various stakeholders, including the public?

These issues should have been the focus of technical discussions and public information prior to the

vote on the rezoning application. However, as the issues were not addressed at that time it has become

even more important that these issues are addressed now before additional tax dollars (both City and

Provincial) are spent on the proposed development.

In addition to those noted on the attached letter as having been sent a copy of the letter, I also

forwarded a copy to Neil Peters, P.Eng. the chief inspector of dikes as well as Peter Mitchell, P.Eng. the

Director of Professional Practice at APEGBC as he is involved in the preparation of guidelines. It has also

been sent to two of the technical authors of the APEGBC guideline for flood hazard and risk assessment,

Dr. Michael Church, P.Geo., and Matthias Jakob, P.Geo. The purpose of including these individuals is


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that they have extensive experience in this field and have worked closely with the Province, Cities,

Towns, Municipalities and Regional Districts in dealing with natural hazards and risks.

Please contact me if you have any questions.

Cheers

Calvin VanBuskirk, P.Eng., FEC, P.Geo.

P.O. Box 201, 360 Ross Street N.E., Salmon Arm, B.C. V1E 4N3 Tel (250) 832-3933 Fax (250) 832-1117(BRITISH COLUMBIA) GEOTECHNICAL ENGINEERS & TERRAIN SPECIALISTS

9 November 2010

File: Salmon River Delta

CITY OF SALMON ARM Box 40

500 2 Avenue NE

Salmon Arm, B.C.

V1E 4N2

Attention: Corey Paiement, Director of Development and Planning

Re: Development on the Salmon River Delta

Dear Sir:

I am writing to you and those copied to express my professional concerns regarding what appears

to be insufficient consideration given to the function and dynamics of the Salmon River delta north

of the Trans Canada highway in Salmon Arm, B.C. Development, including the placement of fill, on

active deltas prevents natural channel and delta forming processes like overbank flooding, channel

migration, channel avulsion and the distribution of sediment. Within the professional and technical

community, development on active deltas and wetlands is well recognized as problematic and

typically results in a requirement for channel bank armoring, diking and regular dredging of stream

channels to mitigate flooding and damage to adjacent infrastructure such as bridges, roads and

buildings. These taxpayer costs can be in the order of hundreds of thousands and even millions of

dollars per year. Examples of the problems and costs associated with development on active deltas

can be found throughout BC and around the world. Disasters both small and large-scale associated

with development on deltas and floodplains are regularly reported in the media.

At present the Salmon River delta is actively propagating northward into Shuswap Lake near the

centre of the delta. In commenting on the present delta, Geoterrain Consultants in May 2010

states: The period between 1974 to 1990 witnessed an unprecedented growth of the delta north of

the railroad almost doubling the size of the delta in Shuswap Lake and forming a new beach to the

east and expanding the beach bar to the west.As the delta propagates the rivers ability to

transport sediment and water is reduced resulting in channel infilling (aggradation), more frequent

overbank flooding, accelerated channel bank scour and higher annual floodwater levels. This causes

channel migration and ultimately leads to channel avulsion. In the case of the Salmon River the

avulsion would be towards the lower lying area to the east, resulting in the Salmon River flowing

northeastward under the eastern bridge for CP Rail (at Hobbs Creek). This shift eastward would

provide a tremendous capacity for natural sedimentation to occur and would reduce the floodwater

pressures on both the highway and CP rail bridges as well as existing rural residential development

to the south and west. City of Salmon Arm 2 9 November 2010 Delta Issues File: Salmon River Delta


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As you are well aware, the City of Salmon Arm has recently approved the rezoning of a 20 acre

parcel of land adjoining the Salmon River to the east, from agricultural land to commercial. Some

non-structural fill material has already been placed on this property blocking what appears to be a

major distributary channel that functioned as a flood overflow channel, directing some of the

Salmon River channel flow eastwards into the Hobbs Creek area (see Figure 1). To protect the land

and proposed development a significant amount of structural fill would be required to elevate theland and buildings a safe distance above the estimated 100 year flood elevation. However, fill

placement alone will not likely be sufficient to protect this land or the development from channel

migration or avulsion. Further protection, likely involving dike construction and riprap armoring

would likely be required to prevent erosion of the fill in the event of an avulsion of the Salmon

River. Depending upon the extent of the permitted development this work would likely result in

additional training of the river.

How does the City evaluate the potential impact of fill placement on the function and dynamics of

floodplains and deltas to reduce the potential for damage to adjacent developments and the

environment?

As the City is now responsible for regulating development on floodplains, when do they plan toupdate the presently outdated, provincial floodplain maps to reflect the present state of the

Salmon River floodplain and delta?

Does the Citys regulation of development on floodplains distinguish the difference between

floodplains and deltas?

Given the change in land use designation and the fact that the City does not have a fill placement

by-law, to what extent will the developer be permitted to place fill and riprap armor to protect the

subject property and proposed development?

If the Salmon River is not permitted to change course and flow to the east, what will be the annual

cost of dredging the river to protect the adjacent properties as well as the highway and CP Rail

bridges?

It is understood that wedges of sediment are currently migrating down the Salmon River. How large

are these wedges and what is their present location?

What is the present rate of migration of the sediment wedges?

What is the potential increase in migration rate of the sediment wedges that could be attributed to

hydrological changes predicted due to the Mountain Pine Beetle impact on the forests?

When are the sediment wedges expected to reach the Salmon River delta?

If the river is not permitted to shift to the east, when will dredging likely be required?

Will the dredging and access works required to facilitate the dredging constitute and hazardousalteration, destruction or disruption of fish habitat (HADD)? City of Salmon Arm 3 9 November 2010Delta Issues File: Salmon River Delta


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Apparent junction of floodwater channel and the Salmon River mainstemRough limits of fill placed on the propertyFloodwaters flow towards Hobbs Creek Bridge siteCP Rails Salmon River Bridge

Figure 1 May 14th

1993 BC Government aerial photograph showing typical flooding within the

Salmon River delta and the function of the floodwater distributary channels during a reported

stream discharge of 43.8m3

/second. Based on Environment Canada stream flow information, peak

annual flood discharges of greater than 40m3

/second were recorded 6 more times since 1993

including 1996 and 1997 when the flows were approximately 59m3

/second. City of Salmon Arm 4 9November 2010 Delta Issues File: Salmon River Delta


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If this work constitutes a HADD where would the compensation work be done and what would be

the likely costs?

How much of the dredging, channel bank protection and compensation costs will become the

responsibility of the Salmon Arm taxpayers?

It is my understanding that the City of Vernon recently completed a dredging project on a9

00mlength of the BX Creek that was previously dredged in the late 1990s. It is understood that the cost

of this project, including compensation for the HADD, was over one million dollars. Adjusting this

cost for the larger size and length of the Salmon River, without consideration for other

anthropogenic and geomorphological differences, the annual cost of dredging the Salmon River

between the highway and the railway could be as much as one million dollars. This would not

include environmental costs. This cost is provided purely for discussion and with little detailed, site

specific information as no detailed study results have been made available to the public.

Given the impact that the present fill and proposed development on the Salmon River delta could

have on the adjacent property owners, taxpayers, and the environment it would have been prudent

for the City to have retained the services of a Profession Engineer and/or Professional Geoscientist

recognized as an expert in the field of fluvial geomorphology (hydrogeomorphology) to assess thedelta and the proposed development and estimate the potential financial and environmental

impacts of the existing fill and proposed development.

It is understood that the initial RAR assessment and report underestimated the elevation and extent

of the Salmon River flood impact on the subject property and proposed infilling of a significant

number and length of floodwater channels to the north of the present fill. The BC Ministry of

Environment commissioned Mike Miles and Associates to review the five year flood elevation

proposed by the developer under the requirements of the RAR. However, the scope of services

requested was reported to be every narrow and the results have not been made public. It is also

understood that a request for a hydrological assessment by the Canadian Department of Fisheries

and Oceans (DFO) was not fulfilled. The present RAR has reduced the proposed footprint of thedevelopment but has not addressed the issue of the existing fill materials that have blocked the

southern distributary flood channel(s). The impact of this fill on the function and dynamics of the

delta represents as yet un-quantified financial and environmental risks to the taxpayer and other

stakeholders.

As a Professional Engineer and Professional Geoscientist I am not aware of any sound reasoning for

promoting or supporting development on the active portion of the Salmon River delta without a

clear understanding of the function and dynamics of the delta, and the support of a detailed fluvial

geomorphological study completed on behalf of the City and addressing the financial and

environmental interests of the taxpayers and other stakeholders.

In conclusion, it is recommended that the City of Salmon Arm retain the services of a recognizedfirm or individual experienced in the field of fluvial geomorphology (hydrogeomorphology) such as

Mike Miles and Associates, Northwest Hydraulics, or Kerr Wood Lidal to assess the present and

future environmental and financial risks to the elements within and adjacent to the Salmon River

delta. The results of this assessment could then help guide City of Salmon Arm 5 9 November 2010 DeltaIssues File: Salmon River Delta


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the City and Council in making informed decisions related to the management of lands and activities

within and adjacent to the active portion of the delta.

The parties that have been sent a copy of this letter are those that: may be directly impacted by

development on the delta; would be required to provide approval for works within the Salmon

River channel and riparian area; or may be requested to provide funding to manage the river

channel, particularly in the event of an emergency.

If you have any questions or require clarification of any of the above issues, please call. I look

forward to your response.

Yours truly,

Terratech Consulting Ltd.

Calvin D. VanBuskirk, P.Eng., FEC, P.Geo.

CC Salmon Arm City Mayor Marty Bootsma

Salmon Arm Councilors: Debbie Cannon, Chad Eliason, Kevin Flynn, Alan Harrison, Ivan

Idzan, Ken Jamieson

Niskonlith Indian Band, Attention: Chief Judy Wilson

Switzmalph Cultural Society, Attention: Bonnie ThomasAdams Lake Indian Band, Attention: Chief Nelson Leon

Department of Fisheries and Oceans Canada, Attention: Bruce Runciman

Department of Fisheries and Oceans Canada, Attention: Michael Crowe

Department of Fisheries and Oceans Canada, Attention: Jason Hwang

Ministry of Environment, Attention: Valerie Cameron, Regional Manager, Water

Stewardship

Ministry of Environment, Attention: Phil Belliveau, Ecosystems Manager

Ministry of Transportation, Attention: Laurie Christianson, Manager of Bridges

Ministry of Transportation, Attention: Murray Tekano, Highways District Manager

Ministry of Transportation, Attention: Tom Kneale, Geotechnical Engineer

Ministry of Transportation, Attention: Kevin Baskin, Chief Bridge EngineerColumbia Shuswap Regional District, Attention: Cliff Doherty, Emergency Preparedness

Coordinator

Provincial Emergency Program, Attention: Mike Knauff, Regional Manager

CP Rail, Attention: Chris Bunce, P.Eng.

Salmon River Round Table, Attention: Mike Wallace, RP. Bio.

WA:TER, Attention: Dr. Warren Bell

MLA Shuswap, Honourable George Abbott

Member of Parliament, Colin Mayes

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