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o c e a n s
e n g i n e e r i n g
l a k e s
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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R. Thomson
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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R. Thomson
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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R. Thomson
December 18, 2015
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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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R. Thomson
December 18, 2015
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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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December 18, 2015
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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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R. Thomson
December 18, 2015
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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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Page 14 of 24
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
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)
-
R. Thomson
December 18, 2015
Page 15 of 24
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
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)
-
R. Thomson
December 18, 2015
Page 16 of 24
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
Photograph 5 Concrete shorewall with armour stone toe (Nov. 25,
2015)
Photograph 6 Close up aerial view of concrete shorewall (Aug. 4.
2015)
-
R. Thomson
December 18, 2015
Page 17 of 24
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
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)
-
R. Thomson
December 18, 2015
Page 18 of 24
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
Photograph 9 Western flank with concrete wall and low stacked
stone wall (foreground)
Photograph 10 Shingles and cobbles on bedrock lakebed (Nov. 25,
2015)
-
R. Thomson
December 18, 2015
Page 19 of 24
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
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)
-
R. Thomson
December 18, 2015
Page 20 of 24
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
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)
-
R. Thomson
December 18, 2015
Page 21 of 24
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
Photograph 15 Example of crack in concrete shorewall (Nov. 25,
2015)
Photograph 16 Example of concrete spalling (Nov. 15, 2015)
-
R. Thomson
December 18, 2015
Page 22 of 24
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
Photograph 17 Evidence of previous concrete repairs (Nov. 25,
2015)
Photograph 18 Crack in wall and toe concrete
-
R. Thomson
December 18, 2015
Page 23 of 24
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
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)
-
R. Thomson
December 18, 2015
Page 24 of 24
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
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)
Stable Slope Allowance 16.2 m
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
INFERRED TOE OF SLOPE (ELEV. 75.0)
BH 2
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
Basement
EDS LIMIT
(20 m Erosion
Allowance)
Erosion Allowance with Like New Shore Protection 20.0 m
Stable Slope Allowance 17.0 m
STABLE SLOPE PROFILE
1.8H : 1V
PHYSICAL TOP OF SLOPE
EXISTING STABLE TOP OF SLOPE
1.4H: 1V
Erosion Allowance with Repairs to Existing Shore Protection 24.0
m
EDS LIMIT
(24.0 m Erosion Allowance)
Stable Slope Allowance 17.3 m
SECTION B-B'
SECTION A-A'
CONCRETE SEAWALL WITH
ARMOUR STONE TOE
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
TYPICAL SECTIONS
12439.101 SKT 02
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
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
very stiff, reddish brown
STABLE SLOPE PROFILE
1.8H : 1V
TIMBER WALL
STABLE SLOPE
ALLOWANCE
INFERRED TOE OF SLOPE (ELEV. 75.0)
SHINGLE/COBBLE BEACH
FILL silty clay, stiff, brown
QUEENSTON FORMATION
weathered shale bedrock, reddish brown
CLAYEY SILT TILL very stiff, reddish brown
Erosion Allowance with Repairs to Existing Shore Protection 30.0
m
EDS LIMIT
(30.0 m Erosion Allowance)
Stable Slope
Allowance 5.3 m
EXISTING STABLE TOP OF SLOPE
SECTION D-D'
EDS LIMIT
(20 m Erosion
Allowance)
Erosion Allowance with Like New Shore Protection 20.0 m
Stable Slope
Allowance 5.2 m
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
TYPICAL SECTIONS
12439.101 SKT 03
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
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
FILL silty clay, stiff, brown
QUEENSTON FORMATION
weathered shale bedrock, reddish brown
CLAYEY SILT TILL very stiff, reddish brown
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
FILL silty clay, stiff, brown
QUEENSTON FORMATION
weathered shale bedrock, reddish brown
CLAYEY SILT TILL very stiff, reddish brown
BH 5
CLAYEY SILT TILL very stiff, reddish brown
QUEENSTON FORMATION
weathered shale bedrock, reddish brown
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
weathered shale bedrock, reddish brown
CLAYEY SILT TILL
very stiff, reddish brown
STABLE SLOPE PROFILE
1.8H : 1V
STABLE SLOPE PROFILE
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
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
4
8
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
TYPICAL SECTIONS
12439.101 SKT 04
1 A REVISION TO EDS LIMIT with Repairs to Existing Shore
Protection BKC CMG MOK 14/12/15