We have highlighted the serious concerns within the document:

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Province of Manitoba Shoreline Erosion Technical Committee

Wisam AbdulRazaq, P.Eng. Chairperson Phone: 204-945-6467 February 24, 2011 Our File No. SETC-2011-01 … Other File No. 31.1.13.7 Mr. Lloyd Talbot, MCIP Selkirk and District Planning Area Board 200 Eaton Avenue Selkirk MB R1A 0W6

Dear Mr. Talbot:

Re: Application for Shoreline Protection Work at Sunset Blvd (Hanson Proposal) – RM of Victoria Beach The Shoreline Erosion Technical Committee (SETC) reviewed a proposal submitted by the Selkirk and District Planning Area Board (SDPB). The proposal was by Mary & Gregg Hanson for shoreline erosion protection at Sunset Blvd. within the RM of Victoria Beach. SETC provides technical advice in the fields of Land Planning, Hydraulics, Geotechnical, Fisheries and Shoreline Processes and hereby offers its comments and suggestions towards the design and construction of the project. RM of Victoria Beach has the legislated mandate for issuing the development permit for projects such as the proposed project; SETC does not have any legal authority to issue development permits.

A. Project Description The SETC understands that the proposed project consists of the following:

The project involves the shoreline protection of 19 shoreline lots including municipal right-of-way on Sunset Blvd. Total length is 1,374 ft or 419 m. Excavating and regrading the shoreline banks for installation of an armour rock structure. Granular fill will be used to slope the existing bank to 1.75H:1V behind the rock armour structure. Placing field stone armour rock of an average size of 0.3 m (1 ft) over the regraded slope. The largest rock size would be 1 m (3 ft). The armour rock slope is 3H:1V. The upper limit of the rock armour erosion protection is at 221.9 m (728 ft) a.s.l., while the lower toe embedment will be at 216.7 m (711 ft) a.s.l. The toe base is 6 ft in width with a slope of 1H:1V on both sides.  Placing drainage filter of pit run graded material over the regraded slopes of 1H:1V and 1.75H:1V on the land side of the armour rock. Placement of a geotextile separator at the base of the embedded armour rock structure.

Installation of a 10 ft wide walkway on top of the armouring rock at 728 ft a.s.l. GENIVAR will be responsible for inspection of the construction, and for undertaking the quality control/quality assurance during construction.

The SETC .s understanding of the proposed erosion protection works is based on the plans and report submitted to the SETC by the SDPD on January 7, 2011 and January 10, 2011.

B. General In broad terms, landowners who are located adjacent to a shoreline that is eroding and receding have three options. The first option is to do nothing and maintain the status quo. This has the advantage of costing nothing, and of maintaining the natural shoreline and natural shoreline processes. However, shoreline erosion and recession will continue and the risk of damage to property and buildings will increase with time. The second option is to relocate the existing development threatened by the shoreline erosion and recession. This maintains the natural shoreline and the natural shoreline processes, and it can be less costly than shoreline protection works. However, it is not always possible for various reasons, and the risk of damage might just be put off until a later date. If there is an opportunity, the SETC recommends that the option of relocating potentially affected structures be considered. The third option is to construct shoreline protection works. The applicants have proposed such works. The balance of this letter will assess and comment on those proposed works.

C. Land Planning and Drainage The applicant must ensure that for all works on municipal or Provincial Crown lands, approval is obtained from the Municipality or the Province for the proposed construction and for access to the site. All works undertaken on privately owned land must also conform to any applicable Municipal, Provincial and Federal legislation. In the design and construction the applicant must be aware that factors such as municipal and private road and lot drainage are highly influential on shoreline stability. These features often block surface drainage and promote shallow groundwater system development, which can lead to shoreline instability and erosion protection failure. Other drainage issues such as septic fields and perforated holding tanks are also significant in the long term performance of erosion protection as they allow water and waste to drain into the lake causing soil loss and slumping of the bank. 3 Natural trees, shrubs, willows and grasses with deep roots provide a stabilizing influence and excellent soil retention capability and resist erosion far more than turf grass alone. The applicant is encouraged to retain as much vegetation as possible during construction of erosion protection works and during ongoing maintenance.

D. Hydraulics and Flood Protection Levels As demonstrated in 2005, 2006, 2009, and again in 2010, Lake Winnipeg wind eliminated levels of 218.4 m (716.6 ft) and higher are possible. With wind and wave events, the water levels in the Victoria Beach area may rise to at least 221.0 m (725 ft). The report indicates that the rock armour erosion protection will be provided to elevation 728 ft. It is typically recommended that erosion protection be provided to at least 221.0 m (725 ft) in the Victoria Beach area to ensure reliable performance over time. However, this minimum design elevation recommendation is based on the erosion protection being sloped at 4H:1V. If the erosion protection is sloped at 3H:1V, the SETC recommends that the rock armour erosion protection be provided to at least 221.6 m (727 ft) to ensure reliable performance over time. The proposal with upper limit of the rock armour erosion protection at 221.9 m (728 ft) is above the minimum elevation of protection recommended by the SETC. The effects of wave action on erosion protection can be severe. A 4H:1V or shallower slope is typically recommended to lessen the effects of wave action on the bank, and to significantly reduce wave run-up and the risk of wave splash which can cause erosion. The report shows that the slope of the proposed erosion protection will be 3H:1V, but the design elevation of the top of the proposed shoreline protection at this slope was increased to account for a slope steeper than what is typically recommended. The SETC finds this to be acceptable, but notes that, typically, constructing erosion protection works with a shallower slope will help increase the longevity of the project. Drainage between the bank soil and the shoreline erosion protection is extremely important and should be carefully designed of adequate size and capacity to allow wave water recession without causing soil erosion, and to allow subsurface seepage and groundwater movement at the bank without causing native soil transport. The report and plans indicate that the gradation for the drain stone will be below 75 mm in diameter, with 40 % to 60% passing the 25 mm sieve. The proposal does not indicate the thickness of the drainage filter. The gradation of the drainage filter should be such that it prevents piping through the filter, provides adequate permeability, and provides uniformity between piping and permeability. Should the drainage filter not be adequate, the build-up of hydrostatic pressures behind the filter can cause a slip plane to form along the filter resulting in massive translational slide failure. The SETC at this point does not have enough technical information to comment on how well the filter will work. 4 The designer indicated in his preliminary report (Wind and Wave Impact) that the stone size required to withstand the hydraulic forces generated by the waves has been computed as 1 cubic metre or weight of 2,000 kg based upon wind of 70 km/hr. The SETC notes that the report and plans indicate the proposed armour rock size is a maximum of 800 mm. This appears to be inadequate to withstand the hydraulic forces identified by the designer. The SETC notes that the wind of the past storm of October 2010 was more than 90 km/hr.

The SETC recommends that the designer should address this issue.

Overtopping of the erosion protection can occur under extreme wind events (more than 90 km/hr). Consequently, allowances for back drainage must be provided to allow large quantities of water to pass through the erosion protection and to return to the lake while avoiding soil erosion that could happen at the shoreline slope and at the top of the bank. The SETC notes that the 10 ft wide walkway could potentially act as a splash pad if the top surface .s material is composed of granular materials of adequate drainage capacity. If sand is used for the surface of the walkway, a geotextile separator is required to prevent sand migration and to insure the function of the free drainage media under extreme wave actions. If asphalt or another impermeable material is used, then the SETC recommends regrading the slope above the walkway and placing light rip rap on the slope above the walkway that will allow wave splash to drain into the layer of filter stone and consequently into the lake. The SETC recommends that the walkway surface should be sloped gently towards the lake. The SETC also recommends planting of deep rooted vegetation above the erosion protection work, on the shoreline slope, and at the top of the bank, such as native willows, sedges and grasses; this will help to stabilize the top of the bank and minimize erosion above the erosion protection zone.

The SETC notes that the report did not indicate the top surface .s material of the walkway. This material should not have a negative impact on the armour rock integrity and should address back drainage issue. To prevent under scour of the soil supporting the erosion protection works, it is typically recommended that a rock toe be embedded to a minimum elevation of 216.7 m (711 ft), which corresponds to 2.5 ft below the average wind eliminated water level of Lake Winnipeg. The drawings indicate that the rock toe will be embedded to elevation 711 ft This meets the minimum toe embedment elevation recommended by the SETC to maximize the long term stability of the erosion protection.

E. Geotechnical and Subsurface Drainage The report indicates the following: (a) the site is primarily composed of fine sand beach overlying silty clay, (b) the shoreline is exposed to prevailing north winds, (c) shoreline recession in this area was 9 m (30 ft) due to high Lake Winnipeg levels throughout 2010 and the extreme storm events, (d) wave height has been computed as 6 ft with 70 km/hr of wind intensity and based upon the fetch distance, (e) the stone size required to withstand these hydraulic forces is 1 m 3 or 2,000 kg, (f) construction 5 will involve filling irregularities in the banks and developing a slope 1.75H:1V as shown in the plan drawings, (g) there is a lack of vegetation at the shoreline, and (h) predominant storms and wave action are from the north winds that produce a high lake setup. The plan drawings show that the top of the bank is 22 ft above the average windeliminated water level. The report indicates that there is a clay strata at elevation 713 ft. However, the SETC notes that the report does not indicate detailed information on the soil stratigraphy, soil engineering properties, groundwater data, subsurface drainage, and till layer data, and does not include a stability analysis. Details on topography, soil stratigraphy, groundwater table, and slope stability analysis are required to check the effectiveness and suitability of this proposed project. The SETC recommends a shoreline stability analysis be undertaken to ensure that the proposed project results in a significant improvement in stability and achieves the minimum required factor of safety. This analysis would provide additional information on any slip surface locations, if they exist. Without the results of this analysis, the SETC cannot come to the conclusion that the proposed shoreline protection works would be effective.

The report did not provide information on groundwater releases, if any. Groundwater flows in the upper banks can cause shoreline upper bank instability, especially after large precipitation events or spring flooding. The SETC recommends that the shoreline upper portion be protected (with rip rap and drainage filter) if there is a possibility of groundwater flow during some time of the year. Based upon the photos provided, it is evident that sloughing is occurring along the bank and the shoreline is very steep. The SETC recommends regrading the upper portion (above the protected area) to a gentler slope to avoid slope failures. It should be noted that a slope of 4H:1V would be ideal to avoid slope failures, but steeper than 4H:1V may also be effective but after conducting an appropriate slope stability analysis. Deep-rooted trees, shrubs, willows and grasses planted on the shoreline upper bank (that is, above the erosion protection works) can provide erosion protection from precipitation and waves in extreme storm events, and increase stability; this can be especially important with steeper slopes.

The report indicates that the project involves shoreline protection of 19 lots. The available information indicates that only 11 landowners have indicated a willingness to be involved in this project. The SETC recommends that this project should only be considered if all owners participate in the project. Undertaking only portions of the project could cause erosion on some of the unprotected properties, with a high potential for liability.

The plan drawings show that the shoreline protection will be transitioned into the adjacent lots. Such transitions are typically recommended by the SETC to avoid causing erosion and eddy currents that could cause damage. However, due to the height and large mass of the proposed project there could be a potential impact on the adjacent lots that are not mitigated by the transitioning of the proposed works into 6 those adjacent lots. Therefore, the SETC recommends this issue should be explicitly addressed.

F. Other Considerations Field inspection during construction is significant. This should ensure that the contractor adheres to all of the technical details of the proposed project and the recommendations. The SETC understands that GENIVAR will undertake the inspection and quality assurance control and all other aspects of quality control. The beach in this area is considered to be a valuable public asset. The proposed project will use some of the beach area for the rock armour structure. It appears that it would be possible, in principle, to move the rock armour structure further inland. However, this might entail additional excavation of the existing banks. Based on the information provided in the proposal, the SETC is not certain that the setback of the erosion protection works has been optimized to maximize beach frontage and minimize infill from the bank excavation. The SETC notes that this proposal has a number of issues that are potentially problematic. Therefore, the SETC suggest that other methods/proposals of shoreline protection be considered.

The report did not comment on the affects of the proposed shoreline erosion protection works on the beach in the vicinity of those works. This issue can be a complex one; the particular details of the proposed works and the natural processes of shoreline aggradation and recession in that vicinity can make it difficult to analyze and make it difficult to predict the impacts on the beach. However, the available information suggests that when the retreat and erosion of a shoreline bluff is stopped by the construction of a shoreline protection works, the downcutting of the shore and beach lakeward of the works will continue. This will lead to the lowering of the shore and beach adjacent to the works, with the potential for the beach to disappear completely.

The SETC recommends that the RM of Victoria Beach should consider hiring a qualified consultant to study these concerns.

G. Fisheries and Habitat Influences . The shoreline is a very important and dynamic habitat area for fish and other wildlife. It is essential to maintain the natural habitat features by minimizing the removal of native vegetation and planting deep-rooted trees and shrubs and grasses. A continuous band of vegetation that starts at the ordinary high water mark and continues up and over the crest of the shoreline will help to stabilize the soils, reduce erosion and provide important shoreline habitat functions. More information on how to do this can be obtained by contacting a qualified riparian plant specialist. The measures in the letter of advice for shoreline protection works on Lake Winnipeg in 2010-2011 from the Department of Fisheries & Oceans Canada should be followed to minimize the potential impacts that any shoreline protection works 7 may have on the fish and fish habitat of Lake Winnipeg. If these measures cannot be implemented then the Department of Fisheries & Oceans Canada should be contacted directly for advice or site specific review (204-983-5163).

SETC .s Recommendations & Conclusions:

1) If there is an opportunity, the SETC recommends the relocation of potentially affected buildings or structures be considered.

2) The SETC notes that the report does not indicate detailed information on the soil stratigraphy, soil engineering properties, groundwater data, subsurface drainage, till layer data, etc along the shoreline. This information is required in order for the SETC to complete its review of the proposed project and provide recommendations.

3) The SETC recommends that a shoreline stability analysis be undertaken to ensure that the proposed results in a significant improvement in stability and achieves the minimum required factor of safety. This information is required in order for the SETC to complete its review of the proposed project and provide recommendations.

4) The SETC notes that the 10 ft wide walkway could act as a splash pad if the top surface .s material is composed of granular materials of adequate drainage capacity, but the report did not indicate the material to be used for the walkway`s top surface The material should not have a negative impact on the rock armour .s integrity, and should address drainage of lake waters back into the lake. If sand is used for the surface of the walkway, a geotextile separator is required to prevent sand migration and to insure the function of the free drainage media under extreme wave actions. If asphalt or another impermeable material is used, the SETC recommends regrading the slope above the walkway and placing light rip rap above the walkway that will allow wave splash to drain into the layer of filter stone and consequently into the lake. The SETC recommends that the walkway surface should be sloped gently towards the lake. The SETC also recommends planting deep rooted vegetation above the erosion protection work, on the shoreline slope, and at the top of the bank, such as native willows, sedges and grasses; this will help to stabilize the top of the bank and minimize erosion above the erosion protection zone.

5) The rock armour erosion protection is to be up to 728 ft, which is above the SETC .s recommended top elevation of 727 ft. The proposed erosion protection will be at a slope of 3H:1V. The SETC concurs with this slope, as the top of the erosion protection works were increased to account of this side slope. It should be noted that, typically, constructing erosion protection works with a shallower slope will help increase the longevity of the project. 8

6) Drainage between the bank soil and the shoreline erosion protection is extremely important . The SETC at this point does not have enough technical information to comment on how well the proposed drainage filter will work.

7) The designer indicated that the stone size required to withstand the hydraulic forces generated by the waves has been computed as 1 cubic metre or weight of 2,000 kg based upon wind of 70 km/hr. The SETC notes that the proposed armour rock size is a maximum of 800 mm. This appears to be inadequate to withstand the hydraulic forces identified by the designer. The SETC notes that the wind of the past storm of October 2010 was more than 90 km/hr. The SETC recommends that the designer should address this issue.

8 ) The rock toe elevation of 711 ft meets the minimum toe embedment elevation recommended by the SETC.

9) Ensure that silt fences, straw blankets, straw mulch and any other appropriate environmental protection are in place during construction to minimize sediment release from exposed soils.

10) The report did not provide information on groundwater release. The SETC recommends that the shoreline upper portion be protected (with rip rap and drainage filter) if there is a possibility of groundwater flow during some time of the year. The SETC also recommends regrading the upper portion (above the protected area) to a gentler slope to avoid slope failures; 4H:1V is ideal, but steeper slopes may also be effective but it is recommended that an appropriate slope stability analysis be conducted.

11) The report indicates that the project involves shoreline protection of 19 lots. The available information indicates that only 11 landowners have indicated a willingness to be involved in this project. Therefore, the SETC recommends that this project should only be considered if all owners participate in the project. Undertaking only portions of the project could cause erosion on some of these properties, with a high potential for liability.

12) The SETC recommends that the impact of the proposed project on the adjacent lots should explicitly be addressed.

13) The SETC notes that the available information suggests that the construction of the shoreline protection works will likely lead to the lowering of the shore and beach adjacent to the works over time, with the potential for the beach to disappear completely. The SETC recommends that the RM of Victoria Beach should consider hiring a qualified consultant to study these concerns.

14) The SETC is not certain that the setback of the erosion protection works has been optimized to maximize beach frontage and minimize infill.

15) Field inspection during construction is significant. The SETC understands that GENIVAR will undertake the inspection and quality assurance control and all other aspects of quality control.

16) Follow the measures provided in the letter of advice for shoreline protection works on Lake Winnipeg in 2010-2011 from the Department of Fisheries and Oceans Canada to minimize the potential impacts that any shoreline protection works may have on the fish and fish habitat of Lake Winnipeg. If these measures cannot be implemented then the Department of Fisheries & Oceans Canada should be contacted directly for advice or site specific review (204- 983-5163). It must be recognized that the suggestions offered above represent the Committee experience on projects of a similar scope and are not intended to be a substitute for professional engineering designs. For these designs, a professional engineering consultant would need to be retained and additional details regarding topography, groundwater table, soil properties, subsurface drainage, etc, would be needed to address the stability and/or shoreline erosion issues.

Yours truly, Wisam AbdulRazaq, Ph.D., P.Eng. Chairperson Shoreline Erosion Technical Committee cc: Shoreline Erosion Technical Committee Members

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