July 17, 2006 - Burlington · Concrete Shorewall The primary concrete shorewall has a recurved...

W . F . B a i r d & A s s o c i a t e s C o a s t a l E n g i n e e r s L t d . w w w . b a i r d . c o m

Baird

o c e a n s

e n g i n e e r i n g

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d e s i g n

r i v e r s

s c i e n c e

w a t e r s h e d s

c o n s t r u c t i o n

B a i r d & A s s o c i a t e s

1267 Cornwall Road, Suite 100

Oakville, Ontario Canada L6J 7T5

T . 9 0 5 8 4 5 5 3 8 5

F . 9 0 5 8 4 5 0 6 9 8

December 18, 2015

Mr. Ron Thomson

39 Pennsylvania Ave. Unit 1

Concord, ON L4K 4A5

By email: Ron Thomson

Dear Ron:

Re: Natural Hazard Assessment and Shoreline Engineering, 105 Avondale Court, Burlington

W.F. Baird & Associates Coastal Engineers Ltd. (Baird) was retained by Ron Thomson (Owner) to

review the existing shoreline conditions and assess the shoreline setback for the proposed

redevelopment at 105 Avondale Court, Burlington. The Owner proposes to demolish the existing

dwelling, merge some of the adjacent lots, and construct a multi-unit residential development.

This assessment was prepared by Baird for Ron Thomson. The material in it reflects the judgment of

Baird in light of the information available to them at the time of preparation. Any uses which a Third

Party makes of this report, or any reliance on decisions to be made based on it, are the responsibility of

such Third Parties. Baird accepts no responsibility for damages, if any, suffered by any Third Party as a

result of decisions made or actions based on this report.

1. Site Conditions

Visual reconnaissance investigations of the shoreline were undertaken on August 4, 2015 and

November 25, 2015. Select photographs from these reconnaissance visits have been referenced in this

letter and are provided at the end of the letter. During the first reconnaissance visit a small Unmanned

Aerial Vehicle (UAV) with a wide angle lens camera was flown above the shoreline of the property and

captured photos at altitudes of 10-50 metres. Oblique views of the shoreline are provided in

Photographs 1, 2 and 3, showing the central portion, west flank and east end respectively.

The lake level recorded by the Canadian Hydrographic Services (CHS) gauge in Burlington at the time

of the reconnaissance investigations were 75.17 m IGLD’85 on August 4, 2015, and 74.58 m IGLD’85

on November 25, 2015. There is no shift between IGLD’85 and the Canadian Geodetic Vertical Datum

1928 (CGVD’28) at the Burlington gauge. All elevations in this report are referenced to CGVD’28,

unless otherwise noted.

A topographic survey of the shoreline from June 2011 (Asenhurst Neouwens Limited Plan No. 11112,

June 10, 2011) was used as the base mapping for the plans in Attachment A. Additional topographic

details of the shorewall, obtained in a follow-up survey, were also incorporated into the plans.

A slope stability assessment was prepared by Terraprobe Inc. on November 4, 2015 (Terraprobe, 2015

– File No. 71-15-5064), and provided to Baird by the Owner. Geotechnical information from this

assessment was used to determine the stable slope allowance of the erosion hazard limit.

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December 18, 2015

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It is not know if an arborist has reviewed the site and assessed if parts of the site fall under the

significant woodland designation. This should be reviewed by your planner.

The Lake Ontario shoreline frontage is approximately 120 m and can be considered as three different

sections based on the existing shore protection, orientation (exposure) and backshore conditions. The

shoreline sections are as follows:

A 95 m long concrete shorewall with armour stone along the toe provides the primary

protection for the southerly side of the site fully exposed to Lake Ontario. Oblique aerial and

ground-level views of this wall are provided in Photograph 1, Photograph 4, and Photograph 5.

An 8 m long (alongshore dimension) shingle/cobble beach is located at the east end of the

property. The beach is backed by a low timber retaining wall. Oblique and ground-level views

of the beach and timber wall are provided in Photograph 7 and Photograph 8, respectively.

The 18 m long western flank of the property is protected by a combination of a 7 m long

section of the concrete shorewall (continuation of the primary shorewall) and a low stacked

armour stone wall (see Photograph 2 and in foreground of Photograph 9). Beyond the property

line, along the western flank, the adjacent property is protected by a higher stacked armour

stone shorewall (in background Photograph 9).

The top elevation of the bluff varies from approximately 84 m at the west side of the site to 77.5 m at

the east side of the site. The bluff face is heavily vegetated with several large trees located immediately

behind the concrete shorewall at both the west and east ends.

Exposed bedrock and covering patches of cobbles and shingles are clearly visible in the nearshore all

along the shore in front of the shorewall (example Photograph 10).

A small drainage course is located at the easterly limit. The outlet of the drainage course is adjacent to

the shingle beach (Photograph 11).

Concrete Shorewall

The primary concrete shorewall has a recurved front face and a cap elevation of approximately 76.40 to

76.45 m. The construction date of the concrete shorewall is not known, but it appears to be several

decades old. The backshore area immediately behind the wall is about 0.5 m lower than the crest of the

wall and about 1.5-2 m wide to the toe of the bluff slope. This area has miscellaneous stone material,

debris and vegetation (Photograph 12). There does not appear to be any formal splash pad behind the

wall.

The water depth at the wall on November 25, 2015 varied but was approximately 0.5 m.

Armour stones and mass poured concrete have been placed at the toe of the concrete shorewall along its

entire length (Photograph 5 and Photograph 6). In places there is a double row of armour stone and

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additional mass poured concrete (Photograph 13). Some steel reinforcing bars were observed in the

poured concrete. The height of the double row of armour stone varies, but is about 1.7 m above the

lakebed. It appears that the armour stone and poured concrete was placed sometime after the original

shorewall construction.

The concrete shorewall is in fair condition. It appears to be upright and in good alignment (Photograph

14). Several cracks (e.g., Photograph 15) and areas of moderate spalling (Photograph 16) are present

and evidence of previous concrete repairs was observed (Photograph 17). The armour stones along the

toe appear to be generally in place and functional as protection. The poured concrete at the toe remains

generally intact, but is showing some deterioration and cracking (Photograph 18). The toe concrete will

continue to deteriorate over time.

We estimate that the combined concrete shorewall with armour stone toe protection has a residual

design life of approximately 20 years. Cracks and spalling in the shorewall should be repaired. A

splash pad should be added behind the crest of the wall. The pad would be about 1.5 – 2 m wide and

consist of heavy stone rip rap over a geotextile.

Shingle/Cobble Beach

The shingle/cobble beach was about 8 m wide from the water line (November 25, 2015) to the timber

retaining wall. The timber wall was about 0.7 m high. The west side of the beach is flanked by stacked

armour stone and a large concrete pad (Photograph 7). The size of the shingle/cobble material can be

seen in Photograph 19.

The shingle/cobble beach should be preserved. The timber wall has little residual design life remaining

(less than 5 years) and should be replaced with a stacked armour stone wall at the back of the beach that

ties into the stone and concrete on the west side of the beach.

Western Flank

The stacked armour stone wall along the western flank of the subject property is too low and is readily

overtopped by wave action. Rip rap stone has been placed behind the wall to mitigate the effects of the

overtopping but it is insufficient. Signs of bluff erosion above the wall were observed during the site

reconnaissance (refer to Photograph 20).

The low stacked armour stone shorewall in its present condition is inadequate to provide erosion

protection and would have to be rebuilt to a higher crest elevation.

Adjacent Shorelines

The shoreline of the adjacent property to the west is protected by a stacked armour stone wall (about

15 m long at west flank) and stacked concrete blocks (Photograph 21). To the east, the adjacent

property is protected by a combination of armour stone and concrete blocks (Photograph 22).

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December 18, 2015

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2. Natural Hazard Assessment and Development Setback

This section provides a description of the policies and reports that were considered in assessing the

natural hazards of the subject property, followed by the details of the assessment for each of the natural

hazards.

Conservation Halton

Under Ontario Regulation 162/06 Conservation Halton (CH) regulates development of the shoreline

within the shoreline hazard limit. Permission is required from CH to undertake development within the

shoreline hazard limit. CH may grant permission for development in hazard areas “…if, in its opinion,

the control of flooding, erosion, dynamic beaches, pollution or the conservation of land will not be

affected by the development”. Conservation Halton’s development standards for the shoreline are based

on their interpretation of the Provincial Policy Statement and supporting Technical Guidelines and are

defined in the “Policies, Procedures and Guidelines for the Administration of Ontario Regulation

162/06 and Land Use Planning Policy Document, 2006” prepared by CH.

The shoreline development setback at the site is governed by the erosion hazard. The following

paragraphs outline the erosion hazard requirements as presently established by Conservation Halton.

The flooding and dynamic beach hazards, which do not govern at this site, are summarized in

subsequent paragraphs.

Erosion Hazard

The Lake Ontario erosion hazard limit is determined by the sum of the erosion hazard allowance,

considering the long-term recession of unprotected shoreline, and the stable slope allowance. With

shoreline protection, the Engineered Development Setback (EDS) can be determined in accordance

with CH policies. In summary, the key requirements of CH with respect to the EDS are as follows:

Development planning horizon: 100 years

Average annual shoreline erosion rate: 0.30 m/yr

Maximum design life for shoreline protection with maintenance access: 35 years

Minimum erosion allowance: 20 metres

Stable slope allowance: 3:1 (or determined by geotechnical study)

Minimum width of maintenance access: 5 metres.

The planning horizon for development is established by CH as 100 years. The average annual shoreline

recession rate is defined by CH as 0.3 m/year. As such, using a 100-year planning horizon, the erosion

allowance for unprotected shoreline is 30 m.

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If shore protection exists, then the erosion allowance component of the EDS may be reduced,

depending on the design life of the protection works. Structure design life is the length of time that a

structure, with routine maintenance, is able to safely and adequately perform its function. Structure

design life differs from the planning horizon of the project. Structures requiring replacement or

significant rehabilitation have reached the end of their useful design life. The primary concrete

shorewall shore protection at 105 Avondale is in fair condition. For the purpose of this report we have

estimated the remaining design life of the existing shore protection structure, with some modest repairs,

to be 20 years, resulting in an erosion allowance of 24 m [(100 yrs – 20 yrs) x 0.3 m/yr].

The maximum design life of shoreline protection permitted by CH is 35 years, even for shoreline

protection that is new, well engineered and well constructed. The design life of a structure can be

extended beyond its original design life by rehabilitation or restoration provided sufficient funds and

suitable construction access are available. Despite this, CH only permits a maximum design life of 35

years. Therefore, for new shore protection the minimum erosion allowance permitted by CH is 20 m

[i.e., (100 yrs - 35 yrs) x 0.3 m/yr].

At the shingle/cobble beach at the east end, either the timber wall at the back of the beach can be

replaced with a new stacked armour stone wall to achieve an erosion allowance of 20 m, or it can be left

as is, requiring an erosion allowance of 30 m. It should be noted that the City may require upgrades to

the timber wall, independent of the requirements of Conservation Halton.

Along the western flank, the low stacked wall needs to be upgraded to provide an appropriate level of

protection.

The erosion allowance is measured from the estimated toe of the natural bluff. The toe of the natural

bluff was estimated as elevation of 75.0 m CGVD.

The erosion allowance components of the EDS at the site with existing shore protection (repaired as

required for the concrete shorewall and no residual life for the western flank and eastern beach) and

with all new shore protection are shown in Attachment A.

The stable slope allowance is then added to the erosion allowance to determine the EDS. The stable

slope allowance is defined by consideration of the geotechnical conditions at a site and the appropriate

factors of safety. The stable slope assessment completed by Terraprobe indicates that the subsurface

profile consists of four main layers:

Top layer (1-2 m of loose silty sand fill);

Upper middle layer (4-6 m compact to dense silty sand);

Lower middle layer (1.0-1.5 m of very stiff clayey silt till);

Bottom layer (weathered Queenston shale.

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Terraprobe determined the safe stable slope inclination is 1.8 horizontal: 1 vertical. The position of the

stable slope allowance along the shoreline is provided in Attachment A.

Maintenance Access

CH policy requires a minimum 5 m wide unobstructed maintenance access to shore (from the road) and

along the shoreline. This is to allow heavy machinery access to the shoreline for regular maintenance

purposes and/or to repair the shore protection works should damage or failure occur. The maintenance

access along the shore can be located within the erosion hazard allowance. Maintenance access to the

shoreline would likely be along the east corridor adjacent to drainage course.

Flood Hazard

The flood hazard at the site is below the top of the existing bank and therefore does not govern at the

site. The flood hazard is a result of the level of Lake Ontario and wave uprush onto the shore. Lake

Ontario water levels fluctuate over the long-term, seasonally, and in the short-term. Long-term

variations are mostly the result of climatic conditions (precipitation, evaporation); other factors, such as

regulation also play a role. Over the past 100 years or so, the mean monthly lake level has varied over a

range of approximately 2.0 m (from elevation 73.75 m to 75.75 m). The average seasonal variation is

from about 74.5 m to 75.0 m. The fluctuation over any given year will vary. The water level typically

peaks during June of each year. The lowest levels generally occur during December and January. The

"stormy season" (when severe wave conditions and storm surge are more likely to occur) generally

extends from October to April. From May to August the probability of severe storms occurring is

reduced. Storm surge, also known as wind setup, is a short-term increase in the water level caused by

the wind blowing across the water.

The 100-year flood level is the combined mean lake level plus storm surge with a return period of 100

years (i.e., on average there is 1% chance in any given year that the lake will reach that level). The 100-

year flood level is 76.0 m CGVD. The flood level does not include the additional effects of wave

uprush at the shoreline. The generic allowance for wave uprush is 15 m measured horizontally from the

100-year flood level. On a bluff shoreline, the horizontal wave uprush offset will be less than 15 m.

The elevation of the tablelands (approximately 84.0 m CGVD) is approximately 8 m above the 100-

year flood level. The flood hazard at the site is therefore readily addressed by the height of the tableland

above the 100-year flood level and does not govern the hazard setback. At the lower portion of the site,

behind the cobble beach, the backshore elevation reaches up to about 77.5 m and is subject to the flood

hazard. However, the generic 15 m wave uprush allowance is less than the minimum required 20 m

erosion allowance, therefore the flood hazard does not govern the hazard setback.

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Dynamic Beach Hazard

There is no dynamic beach, as defined by the policies, at the site. Therefore, there is no dynamic beach

hazard.

Drainage Course Hazard

The drainage course hazard was established by Terraprobe and is shown on drawings in Attachment A.

The setback includes:

5 m toe erosion allowance

Stable slope allowance

7.5 m setback from top of stable top of slope.

City of Burlington

It is our understanding that the Owner is proposing to redevelop the property into multiple units. In

cases such as this, the City of Burlington Land Use Policies may require additional setbacks. The City

may require the shoreline protection for the newly acquired park to be new or like new condition, with a

design life meeting the typical standards of Conservation Halton. For this particular redevelopment

proposal, we recommend that you establish the requirements for the City of Burlington park dedication

and rear yard setbacks directly with the City.

Natural Hazard and Development Setback Summary

The following summarizes the natural hazard and development setbacks that apply to 105 Avondale

Court:

The Engineered Development Setback (EDS) is defined by the erosion hazard and the stable

slope allowance.

Erosion Allowance (dependent on the design life of the shore protection):

o 30 m without any shore protection or protection with no residual life

o 24 m with the existing shore protection with repairs (assuming 20 year remaining

design life)

o 20 m with new or like-new engineered shore protection (minimum 35 year design life).

Erosion allowance is measured horizontally from toe of the natural bluff at elevation 75.0 m.

Stable slope allowance presented by Terraprobe is 1.8:1.

Required 5 m wide maintenance access along the shore is located within the erosion hazard

allowance.

5 m wide maintenance access must be provided perpendicular to the shoreline from the road.

Recommend consultation with planner to confirm City parkland and rear setback requirements.

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Cross-sectional and plan drawings which delineate the natural hazards are included in Attachment A.

3. Shore Protection

The changing water levels, severe wave action, ongoing nearshore lakebed erosion, and ice forces result

in hazards to shoreline properties. Protection works can reasonably mitigate these hazards but do not

eliminate the hazards entirely. There is a risk that the lake conditions will exceed the design conditions

of the protection structure and the structure may be damaged, requiring repair. Also, as noted, shoreline

protection structures have a finite design life.

Concrete Shorewall

Two general shoreline protection options were identified for determining the EDS for the concrete

shorewall portion of the site: 1) repair the existing protection as is and achieve 20 year design life; and

2) rebuild existing protection to achieve minimum design life of 35 years recognized by Conservation

Halton.

1) Several repairs to the existing concrete shorewall need to be made in order for the shorewall to

achieve a 20 year design life. These repairs include:

Grouting or filling any cracks in the concrete;

Patching repairs made to any spalling concrete;

Construction of a rip rap splash pad behind the wall. This splash pad would be approximately

2 m wide, and would have geotextile placed underneath.

2) If you wish to forego any repairs and would like to upgrade or replace the existing shorewall in order

to achieve a design life of 35 years, new shore protection could be designed and constructed. The

design life of this new shore protection would likely exceed 35 years; however CH only permits a

design life of 35 years. Should you wish to improve the shore protection at this property such that it is

like new, there are several alternatives to improving or replacing the existing shoreline protection:

Armour Stone Structures

A sloped (2:1 horizontal:vertical) armour stone revetment consists of quarried armour stone blocks

placed over an underlayer of riprap stone. Figure 1 shows an example of an armour stone revetment.

Local experience has shown well designed and constructed sloping armour stone revetments to be

reasonably durable, have a good track record, and perform well under the prevailing lake conditions.

Experienced local shoreline contractors can readily construct this type of structure. Typically, the cost

of an armour stone revetment is about $4,000 per metre of shoreline. Costs for a stacked armour stone

wall would likely be comparable to the costs associated with an armour stone revetment. It is likely that

some of the stone or concrete from the existing walls could be used in the new structure, which may

lower the cost of materials. This amount of material would be estimated during the design phase and

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has not been accounted for in this preliminary cost estimate. The revetment would likely be built in

front of the existing concrete shorewall.

Boulder Berm

A boulder berm consists of multiple layers of rounded stone. It would have a milder slope than the

armour stone revetment (approximately 3:1) and would be constructed in front of the existing

protection (example shown in Figure 2). The cost of a boulder berm is about $3,500 per metre of

shoreline. Due to the gentler slope, the boulder berm would occupy more of the exiting lakebed.

Figure 1 Example of an Armour Stone Revetment (foreground)

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Figure 2 Example of Boulder Berm

The boulder berm approach may be viewed as favourable by CH, as these structures have milder slopes

and are less reflective to wave energy than steeper sloped revetments. In addition, the smaller stone

material provides diversity for aquatic habitat. These types of shorelines are consistent with the

principles of the Halton Waterfront – Shoreline and Aquatic Habitat Restoration Strategy. However,

these berm/beach type shorelines also occupy more lakebed than an armour stone revetment, which

MNR or DFO may not view as favourable. The natural hazard limits and corresponding EDS associated

with the boulder berm are the same as the limits associated with construction of a new armour stone

structure.

Western Flank

Along the western flank, the stacked armour stone wall will have to be rebuilt with new shore

protection, similar to the revetment option presented above.

Beach

The cobble beach should be retained. Based on the condition of the existing shore protection it is our

opinion that the timber wall behind the cobble /shingle beach at the east end of the property should be

replaced with new shore protection, such as an armour stone revetment or boulder berm.

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4. Permitting Requirements

Permits for any work in or near the water, including shore protection, will be required from CH,

Department of Fisheries and Oceans Canada (DFO), and the Ontario Ministry of Natural Resources

(MNR).

Conservation Halton

A permit for shoreline development will be required from CH. CH also acts in a review capacity for

planning applications in the City of Burlington. The City establishes conditions based on the

requirements of CH. It is recommended that discussions be initiated with CH as soon as preliminary

designs are developed. Owners of neighbouring properties must be provided with the opportunity to

comment on the proposed work.

Department of Fisheries and Oceans – Federal Fisheries Act

Authorization may be required from the DFO under the Federal Fisheries Act. It is recommended that

discussions be initiated with DFO as soon as preliminary designs are developed. Once the design

development phase is complete, they will review and advise whether or not an Authorization is

required.

Ontario Ministry of Natural Resources

Work along the shorelands may require a Work Permit from the MNR. Unless there is a water lot, or

some other legal property designation giving title to the shore owner, the lakebed below the water level

is Crown Land administered by MNR. If it is proposed to locate works on Crown Land, it may be

necessary to acquire or lease the land from the province.

5. Summary

The existing primary concrete shorewall with armour stone toe protection has an estimated residual

design life of approximately 20 years, provided some repairs are undertaken. The erosion allowance

along the southern edge of the property is 24 m with the existing concrete shorewall and repairs, or

20 m with new shore protection. The armour stone wall along the western flank is in poor condition,

has no estimated residual design life remaining, and needs to be rebuilt. The shingle/cobble beach at the

east side should be retained, however, the existing timber beach wall at the back of the beach has no

residual design life remaining and as is requires a 30 m erosion allowance. If the beach wall is rebuilt

as a stacked armour stone wall (and the beach is retained), the erosion allowance could be reduced to

20 m. The stable slope allowance is added to the erosion allowance to establish the Engineering

Development Setbacks. The erosion allowance and associated Engineering Development Setbacks with

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existing and new shore protection are delineated in the drawings provided in Attachment A. Any

parkland dedication and rear yard setbacks should be confirmed by your planner.

A summary of the approximate costs for the various shore protection options for the three sections of

the shoreline is provided in Table 1. Note that the costs associated with replacing the concrete shorewall

are only applicable if you wish to have an erosion allowance of 20 m along the southern edge of the

property.

Table 1 Approximate costs for various shore protection options

Western Flank

(18m)

Concrete Shorewall

(95 m)

Wall at East Beach

(17 m)

Shorewall Repairs n/a $60,000

(for 24 m EDS) n/a

Armour Stone

Structure $72,000

$380,000

(for 20 m EDS) $68,000

Boulder Berm $63,000 $333,000

(for 20 m EDS) n/a

We trust this information meets with your approval. If you have any questions please do not hesitate in

contacting our office.

Yours truly,

W.F. Baird & Associates Coastal Engineers Ltd.

Chris Gibbons, P.Eng.

Project Engineer, Associate

Enc: Attachment A – Natural Hazard and Engineered Development Setback Delineation Drawings (4 pages)

Cc: Mark Kolberg

12439.101

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References

Ministry of Natural Resources (MNR). 2001. Natural Hazards Guide for Great Lakes – St. Lawrence

River System and large inland lakes, river and stream systems, and hazardous sites. Report 51499

(5.0kP.R., 30 03 01). Queen’s Printer for Ontario, Ontario.

Ontario Regulation (162/06). Regulation of the Development, Interference with Wetlands, and

Alterations to Shorelines and Watercourses. Published by the Conservation Halton under the

Conservation Authorities Act. May, 2006.

Terraprobe, 2015. Geotechnical Investigation and Engineering Review of Slope Stability – 105

Avondale Court and 143 Bluewater Place, Burlington ON. Report prepared by Terraprobe Inc.

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Photograph 1 Oblique aerial view of shoreline at 105 Avondale Court (Aug. 4, 2015)

Photograph 2 Oblique aerial view of western flank (Aug. 4, 2015)

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Photograph 3 Oblique aerial view of shingle/cobble beach at east end (Aug. 4, 2015)

Photograph 4 Oblique aerial view of concrete shorewall with armour stone toe (Aug. 4, 2015)

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Photograph 5 Concrete shorewall with armour stone toe (Nov. 25, 2015)

Photograph 6 Close up aerial view of concrete shorewall (Aug. 4. 2015)

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Photograph 7 Oblique aerial view of shingle/ cobble beach at east end (Aug. 4, 2015)

Photograph 8 Shingle/cobble beach backed by timber wall at east end (Nov. 25, 2015)

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Photograph 9 Western flank with concrete wall and low stacked stone wall (foreground)

Photograph 10 Shingles and cobbles on bedrock lakebed (Nov. 25, 2015)

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Photograph 11 Drainage course outlet at east side of site (Nov. 25, 2015)

Photograph 12 Area behind primary concrete shorewall and bluff face (Nov. 25, 2015)

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Photograph 13 Example of double row of armour stone and mass concrete (Aug. 4, 2015)

Photograph 14 Concrete shorewall and toe protection in fair condition (Nov. 25, 2015)

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Photograph 15 Example of crack in concrete shorewall (Nov. 25, 2015)

Photograph 16 Example of concrete spalling (Nov. 15, 2015)

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Photograph 17 Evidence of previous concrete repairs (Nov. 25, 2015)

Photograph 18 Crack in wall and toe concrete

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Photograph 19 Shingle/cobble beach (field book is 20 x 14 cm).

Photograph 20 Erosion of bluff behind low armour stone wall along western flank (Nov. 25, 2015)

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Photograph 21 Adjacent west property (right side, stacked armour stone; left side, concrete blocks)

Photograph 22 Adjacent east property

BH 2

BH 1

BH 3

BH 4

BH 5

D

F'

F

EDS Limit

WITH REPAIRS TO

EXISTING SHORE

PROTECTION

EDS Limit

WITH LIKE NEW

SHORE PROTECTION

VALLEY LANDS

LONG TERM STABLE

TOP OF SLOPE

(TERRAPROBE 2015)

VALLEY LANDS

7.5m REGULATORY

SETBACK

(TERRAPROBE 2015)

TIMBER WALL

SHINGLE/COBBLE

BEACH

ARMOUR STONE

REVISIONS

REV

(T.I.)

T.I.

TYPE OF

ISSUE

DESCRIPTION DRN DSN APR DATE

REV T.I. DESCRIPTION DRN DSN APR DATE

REVISION

PREPARED FOR:

(A) PRELIMINARY

(B) FOR REVIEW (D) FOR INFORMATION (F) FOR CONSTRUCTION

(G) AS BUILT

(H) CANCELLED

(E) CONTRACT DOCUMENT(C) FOR APPROVAL

PREPARED BY:

DRAWING NUMBER:

ISSUE

PREPARED WITH:

105 AVONDALE CT. BURLINGTON

NATURAL HAZARD ASSESSMENT

PLANVIEW

12439.101 SKT 01

1 A REVISION TO EDS LIMIT with Repairs to Existing Shore Protection BKC CMG MOK 14/12/15

1. SUPPLEMENTARY SURVEY MEASUREMENTS OF EXISTINGSEAWALL PROVIDED BY MACKAY PETERS LIMITED 2015

2. ELEVATIONS REFERENCED TO CITY OF BURLINGTON BENCHMARKNo 380. BRASS PLAQUE ON THE NORTH FACE AT THE TOPNORTHWEST CORNER OF A CONCRETE RETAINING WALL AT THENORTHEAST CORNER OF THE INTERSECTION OD POPLAR DRIVEAND LAKESHORE ROAD. ELEVATION 82.57m

3. ALL DIMENSIONSAND DISTANCES IN METRES UNLESS OTHERWISENOTED

5. GEOTECHNICAL INFORMATION PROVIDED BY TERRAPROBE(2015) PROJECT NUMBER 71-15-5064

Meters

0

6

12

9876 65646362616059585756555453525150494847464544434251 2 3 4 10 11 201918171615141312 21 22 23 24 25 30292827260 4140393837363534333231

DISTANCE (m)

717069686766

76

77

78

79

80

81

82

86

85

84

83

ELE

VA

TIO

N (m

), geodetic datum

73

74

75

72

71

70

WL 76.0 (100 year)

WL 74.8 (AUG 2015)

LAKE ONTARIO

BH 1

FILL

silty sand, loose, brown

QUEENSTON FORMATION

weathered shale bedrock, reddish brown

SILTY SAND, trace gravel

compact to dense, lt. brown

CLAYEY SILT TILL

very stiff, reddish brown

CONCRETE SEAWALL WITH

ARMOUR STONE TOE

1.3H: 1V

Erosion Allowance with Like New Shore Protection 20.0 m

STABLE SLOPE

PROFILE

1.8H : 1V

Stable Slope Allowance 16.3 m

INFERRED TOE OF SLOPE (ELEV. 75.0)

EDS LIMIT

(20 m Erosion

Allowance)

PHYSICAL TOP OF SLOPE

EXISTING STABLE TOP OF SLOPE

Erosion Allowance with Repairs to Existing Shore Protection 24.0 m

EDS LIMIT

(24.0 m Erosion Allowance)


9876 65646362616059585756555453525150494847464544434251 2 3 4 10 11 201918171615141312 21 22 23 24 25 30292827260 4140393837363534333231

DISTANCE (m)

717069686766

76

77

78

79

80

81

82

86

85

84

83

ELE

VA

TIO

N (m

), geodetic datum

73

74

75

72

71

70

WL 76.0 (100 year)

WL 74.8 (AUG 2015)

LAKE ONTARIO


BH 2

FILL

silty sand

loose, brown

QUEENSTON FORMATION


SILTY SAND,

trace gravel

compact to dense

lt. brown

CLAYEY SILT TILL


Basement

EDS LIMIT

(20 m Erosion

Allowance)



STABLE SLOPE PROFILE

1.8H : 1V

PHYSICAL TOP OF SLOPE


1.4H: 1V


EDS LIMIT



SECTION B-B'

SECTION A-A'

CONCRETE SEAWALL WITH

ARMOUR STONE TOE

REVISIONS

REV

(T.I.)

T.I.

TYPE OF

ISSUE



REVISION

PREPARED FOR:

(A) PRELIMINARY


(G) AS BUILT

(H) CANCELLED


PREPARED BY:

DRAWING NUMBER:

ISSUE

PREPARED WITH:



TYPICAL SECTIONS

12439.101 SKT 02






Meters

0

4

8

9876 65646362616059585756555453525150494847464544434251 2 3 4 10 11 201918171615141312 21 22 23 24 25 30292827260 4140393837363534333231

DISTANCE (m)

777675747372717069686766

76

77

78

79

80

81

82

86

85

84

83

ELE

VA

TIO

N (m

), geodetic datum

73

74

75

72

71

70

WL 76.0 (100 year)

WL 74.8 (AUG 2015)

LAKE ONTARIO

BH 3

BH 4

FILL

CLAYEY SILT TILL



1.8H : 1V

TIMBER WALL

STABLE SLOPE

ALLOWANCE


SHINGLE/COBBLE BEACH

FILL silty clay, stiff, brown

QUEENSTON FORMATION


CLAYEY SILT TILL very stiff, reddish brown


EDS LIMIT


Stable Slope

Allowance 5.3 m


SECTION D-D'

EDS LIMIT

(20 m Erosion

Allowance)


Stable Slope

Allowance 5.2 m

REVISIONS

REV

(T.I.)

T.I.

TYPE OF

ISSUE



REVISION

PREPARED FOR:

(A) PRELIMINARY


(G) AS BUILT

(H) CANCELLED


PREPARED BY:

DRAWING NUMBER:

ISSUE

PREPARED WITH:



TYPICAL SECTIONS

12439.101 SKT 03






Meters

0

4

8

9876 656463626160

595857565554535251

50494847464544434251 2 3 4

1011

201918171615141312 21 22 23 24

25 30292827260 41

40393837363534333231

DISTANCE (m)

767574737271

7069686766

76

77

78

79

80

81

82

86

85

84

83

ELE

VA

TIO

N (m

), geodetic datum

73

74

75

72

71

70

BH 3


QUEENSTON FORMATION



9876 656463626160

595857565554535251

50494847464544434251 2 3 4

1011

201918171615141312 21 22 23 24

25 30292827260 41

40393837363534333231

DISTANCE (m)

7473727170

69686766

76

77

78

79

80

81

82

86

85

84

83

ELE

VA

TIO

N (m

), geodetic datum

73

74

75

72

71

70

76

77

78

79

80

81

82

86

85

84

83

73

74

75

72

71

70

FILL

silty sand, loose, brown

BH 4


QUEENSTON FORMATION



BH 5


QUEENSTON FORMATION


GABION WALL

CREEK

CREEK

5.0 m

EROSION

ALLOWANCE

3.7 m

LONG TERM STABLE TOP OF SLOPE

(TERRAPROBE 2015)

STABLE SLOPE

ALLOWANCE

5.0 m

EROSION

ALLOWANCE

5.6 m

STABLE SLOPE

ALLOWANCE

BH 2

FILL

silty sand

loose, brown

QUEENSTON FORMATION


CLAYEY SILT TILL



1.8H : 1V


2H : 1V

SILTY SAND, trace gravel

compact to dense, lt. brown

SECTION E-E'

SECTION F-F'

REGULATORY SETBACK

(TERRAPROBE 2015)

7.5 m

LONG TERM STABLE TOP OF SLOPE

(TERRAPROBE 2015)

REGULATORY SETBACK

(TERRAPROBE 2015)

7.5 m





Meters

0

4

8

REVISIONS

REV

(T.I.)

T.I.

TYPE OF

ISSUE



REVISION

PREPARED FOR:

(A) PRELIMINARY


(G) AS BUILT

(H) CANCELLED


PREPARED BY:

DRAWING NUMBER:

ISSUE

PREPARED WITH:



TYPICAL SECTIONS

12439.101 SKT 04


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July 17, 2006 - Burlington · Concrete Shorewall The primary concrete shorewall has a recurved...

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