This document analyzes the impact of riprap on coastal erosion in Miramichi, New Brunswick between 1944 and 2012. The author used historical aerial photos and GIS software to measure changes in the coastline and calculate erosion and deposition rates at three sites - two without riprap (Sites A and C) and one with riprap installed between 1965-1976 (Site B). The results showed rates of erosion decreased by 37% along riprapped sections but increased significantly at the unprotected sites, by over 5000% at Site A and 2900% at Site C. By 2012, 89% of the coastline was riprapped. While riprap lowered erosion rates where installed, unprotected areas experienced higher erosion than before development
It's not just about Alberta: Oilsands generate thousands of jobs, billions in...Ports-To-Plains Blog
This report provides strategic insights by examining the impacts the oil sands industry has made on North American economies and how the industry will likely develop into the future. Two themes are central to the report: impact on Canadian provincial and national economies, and the oil sands’ ripple effects on US state and federal economies.
This is a technical support manual for Knowledge Net (KNET). KNET is a Learning Management System provides teachers with instructional tools and resources; parents with instant access to teachers, coursework and upcoming tests; and students with the ability to communicate with peers and submit homework assignments.
It's not just about Alberta: Oilsands generate thousands of jobs, billions in...Ports-To-Plains Blog
This report provides strategic insights by examining the impacts the oil sands industry has made on North American economies and how the industry will likely develop into the future. Two themes are central to the report: impact on Canadian provincial and national economies, and the oil sands’ ripple effects on US state and federal economies.
This is a technical support manual for Knowledge Net (KNET). KNET is a Learning Management System provides teachers with instructional tools and resources; parents with instant access to teachers, coursework and upcoming tests; and students with the ability to communicate with peers and submit homework assignments.
Primavera p6 18.8 planning and scheduling guide r3Matiwos Tsegaye
This manual is developed to assist construction professional in understanding the basic principles of planning and to guide them how planning is developed using the recent edition Primavera Professional P6 18.8.
A group of over a hundred pits, postholes and stakeholes were located on the hilltop at Stagpark. The features dated from the Early Bronze Age to the Middle Iron Age which would suggest that the hilltop was occupied over a long period of time. Four pits containing burnt fills were recorded in Area A and Area C. The pits were similar in terms of morphology, size and date. The two sets of pits were located within 1m of each other and c. 40m apart. Almost identical Early Bronze Age dates were returned for two of the pits. The pits may have functioned as cremation pits, although minute traces of burnt bone was recorded in only one of the fills. They may also have been utilised for a domestic purpose. One of the two large pits (C.1001) in Area B was dated to the Early Bronze Age. It is difficult to interpret the function of these pits as they are exceptionally large. Stakeholes recorded on the upper sides of pit C.1001, these may have formed a frame or covering for the pit.
The recovery of two sherds of Late Bronze Age coarse ware from a pit, in the vicinity of the hearth-pit C.22, in the northwest section of Area A, would indicate that this area was utilised during the Late Bronze Age. A cluster of three pits and eight stakeholes were located to the southeast of the hearth.
Four of the stakeholes in particular could have formed a shelter around the hearth open to the west.
Although no dating evidence was obtained from the features in the vicinity of the large pits C.66 and C.90 it is possible that they are associated with the Late Bronze Age activity surrounding the hearth C.22.
A Middle Iron Age date was returned from the later re-cut of the large pit C.110. An L-shaped alignment, consisting of three pits, 13 stakeholes and three postholes, extended to the north and east of the pit. The alignment measured c. 6m north-south by 13m east-west. It could be associated with the Middle Iron Age pit C.110, the Early Bronze Age cremation pits or the Late Bronze Age features.
A number of fulachta fiadh were recorded downslope to the north and south of the site. Three burnt mounds were recorded (CO019-019, -020 and -021) within 500m of the site, while four other burnt mounds were excavated as part of this road project; Stagpark 1 (04E1119) was 600m to the south, Stagpark 2 (04E1121) was 200m away to the north and Mitchelstown 2 (04E1071) was 1.5km to the north. The fulachta fiadh are located on heavier clay subsoil. Radiocarbon dates obtained from some of the burnt mounds would suggest that these sites were utilized during the Early Bronze Age.
The site, possibly located on the margins of prehistoric settlement, forms an interesting contrast to a Middle Bronze Age settlement site excavated at Mitchelstown 1 (04E1072). The remains of at least three circular houses were excavated at Mitchelstown 1. The site was located on a limestone ridge on the northern bank of the Gradoge River. The opposing site on the southern bank of the Gradoge River was subsequently occupied by the Anglo Normans in the thirteenth century. The material evidence recorded on site was scant. No associated pits and stakeholes were associated with the structures. It is possible that these features were located outside the route corridor.
Modellers guide – vejledning fra DHI
Berislav Tomicic, DHI
Det er i høj grad DHI’s modelleringsværktøjer, der bruges i DK til dimensionering af nye anlæg til afledning af regnvand. DHI har udarbejdet en vejledning til modellørerne, som vil blive præsenteret i dette indlæg.
Primavera p6 18.8 planning and scheduling guide r3Matiwos Tsegaye
This manual is developed to assist construction professional in understanding the basic principles of planning and to guide them how planning is developed using the recent edition Primavera Professional P6 18.8.
A group of over a hundred pits, postholes and stakeholes were located on the hilltop at Stagpark. The features dated from the Early Bronze Age to the Middle Iron Age which would suggest that the hilltop was occupied over a long period of time. Four pits containing burnt fills were recorded in Area A and Area C. The pits were similar in terms of morphology, size and date. The two sets of pits were located within 1m of each other and c. 40m apart. Almost identical Early Bronze Age dates were returned for two of the pits. The pits may have functioned as cremation pits, although minute traces of burnt bone was recorded in only one of the fills. They may also have been utilised for a domestic purpose. One of the two large pits (C.1001) in Area B was dated to the Early Bronze Age. It is difficult to interpret the function of these pits as they are exceptionally large. Stakeholes recorded on the upper sides of pit C.1001, these may have formed a frame or covering for the pit.
The recovery of two sherds of Late Bronze Age coarse ware from a pit, in the vicinity of the hearth-pit C.22, in the northwest section of Area A, would indicate that this area was utilised during the Late Bronze Age. A cluster of three pits and eight stakeholes were located to the southeast of the hearth.
Four of the stakeholes in particular could have formed a shelter around the hearth open to the west.
Although no dating evidence was obtained from the features in the vicinity of the large pits C.66 and C.90 it is possible that they are associated with the Late Bronze Age activity surrounding the hearth C.22.
A Middle Iron Age date was returned from the later re-cut of the large pit C.110. An L-shaped alignment, consisting of three pits, 13 stakeholes and three postholes, extended to the north and east of the pit. The alignment measured c. 6m north-south by 13m east-west. It could be associated with the Middle Iron Age pit C.110, the Early Bronze Age cremation pits or the Late Bronze Age features.
A number of fulachta fiadh were recorded downslope to the north and south of the site. Three burnt mounds were recorded (CO019-019, -020 and -021) within 500m of the site, while four other burnt mounds were excavated as part of this road project; Stagpark 1 (04E1119) was 600m to the south, Stagpark 2 (04E1121) was 200m away to the north and Mitchelstown 2 (04E1071) was 1.5km to the north. The fulachta fiadh are located on heavier clay subsoil. Radiocarbon dates obtained from some of the burnt mounds would suggest that these sites were utilized during the Early Bronze Age.
The site, possibly located on the margins of prehistoric settlement, forms an interesting contrast to a Middle Bronze Age settlement site excavated at Mitchelstown 1 (04E1072). The remains of at least three circular houses were excavated at Mitchelstown 1. The site was located on a limestone ridge on the northern bank of the Gradoge River. The opposing site on the southern bank of the Gradoge River was subsequently occupied by the Anglo Normans in the thirteenth century. The material evidence recorded on site was scant. No associated pits and stakeholes were associated with the structures. It is possible that these features were located outside the route corridor.
Modellers guide – vejledning fra DHI
Berislav Tomicic, DHI
Det er i høj grad DHI’s modelleringsværktøjer, der bruges i DK til dimensionering af nye anlæg til afledning af regnvand. DHI har udarbejdet en vejledning til modellørerne, som vil blive præsenteret i dette indlæg.
This report comprises the Final Report of excavations undertaken by Eachtra Archaeological Projects along the line of the proposed Castledermot Sewerage Scheme in 2004. Kildare County Council proposed to upgrade the sewerage system in Castledermot village running from the Lerr River to the south along Abbey St. and Main St. to Skenagun to the north. The present town contains extensive archaeological remains, both upstanding and subsurface, of the earlier Medieval town (KD040-002). Therefore in 2002, an archaeological assessment of the proposed line of the sewerage trench was carried out (Byrne 2000). This was followed by a programme of test excavations (Lynch 2002). The results of this work led to a decision to archaeologically resolve the line of the proposed pipe trench in advance of commencement of construction works. Eachtra Archaeological Projects excavated the line of the proposed trench between June and December 2004 under excavation licence number 04E0750. While the excavated trench was narrow, it offered a lengthy cross-section of the Medieval and Post-Medieval town. The excavation revealed a number of facets of the town during these periods including the Medieval town walls and a cemetery. Following archaeological resolution of the trench, it was backfilled to be opened at a future date for the insertion of the sewerage pipes.
This bulletin gives an estimate of the accuracy of MERCATOR OCEAN’s analyses and forecast for the season of April-May-June 2010. It also provides a summary of useful information on the context of the production for this period. Diagnostics will be displayed for all MERCATOR OCEAN’s monitoring and forecasting systems currently producing daily 3D temperature salinity and current products. Finally we present a preliminary intercomparison of a few physical processes viewed by the operational systems and by ORCA12 (with and without data assimilation). The results show that the global ¼° and the Atlantic and Mediterranean 1/12° analyses and forecast still behave very similarly with an accuracy close to the expected levels (as defined in scientific qualification documents), except for the 1/12° displaying significantly better performance in the Mediterranean sea. Anyway this basin tends to be too warm in the model. The global 1/12° (in demonstration) displays at least as good performance and especially less biases than the current systems.
Red Sea - Dead Sea Water Conveyance - Feasibility Study - report summaryasafeiran
RED SEA - DEAD SEA WATER CONVEYANCE STUDY PROGRAM
Draft Final Feasibility Study Report
COYNE-ET BELLIER in association with TRACTEBEL ENGINEERING and KEMA
Most of the archaeological features recorded during this excavation were pits, 26 in total, two walls and a well were also excavated.
Most of the contexts were dated according to the artefacts retrieved from their fills. Therefore, pits with exclusively or almost exclusively medieval pottery were classified as medieval, whereas pits with medieval and post-medieval finds were classified as post-medieval. However, as most of the excavated features were backfilled, it is possible that some of the cut features that contained deposits, with inclusions of post-medieval artefacts, were actually open and in use in the medieval period.
The remains uncovered can be divided into medieval, post-medieval and modern. The pits were in general sub-circular and oval in plan, and, with the exception of pit C.98, were on average 2.06 m in length by 1.36 m in width by 0.61 m in depth. The fills of the pits were a mix of dark grey brown silty clay with occasional inclusions of animal bone and pottery. A total of 26 pits, two walls and a well were recorded.
Assessment of New York City Natural Gas Market Fundamentals and Life Cycle Fu...Marcellus Drilling News
A study released on August 27, 2012 by NYC Mayor Michael Bloomberg outlining the critical role natural gas has and will play in a sustainable energy future for NYC. Bloomberg is using the report to bolster his support of fracking in New York State and his support to rapidly expand the amount of natural gas available for NYC through new pipelines and new sources like Marcellus Shale gas.
This project was a part of the DTU course Wind Farm Planning and Development.
Greater Gabbard is an existing offshore wind farm of 504 MW located 23 km from the Suffolk coast in UK. In this Project, I colaborated with Guido Luis Grassi Gonzalez, Sam Nivin Deepa Rosaline and Spandan Das to investigate the optimization of the AEP of this wind farm by changing the type of turbines used while keeping the total installed capacity. Achieving this would lead to better space utilization, higher yield and lower global costs, reducing the return period of the investment.
The Impact of Riprap on Coastal Erosion in Miramichi, New Brunswick
1. The Impact of Riprap on Coastal Erosion in Miramichi, New Brunswick
By David Williams
June 22, 2015
2. The Impact of Riprap on Coastal Erosion in Miramichi, New Brunswick
3. The Impact of Riprap on Coastal Erosion in Miramichi, New Brunswick
By: David Williams
June 22, 2015
For: NBCC Environmental Technology Program
Applied Research for Engineering and Science-Based Technologies
ETTG 1016
4. iv
Table of Contents
Executive Summary.......................................................................................................... viii
1.0 Introduction.............................................................................................................. 1
2.0 Background ................................................................................................................... 2
2.1 Land use .................................................................................................................... 3
2.2 Ecoregion.................................................................................................................. 3
2.3 Site Geology.............................................................................................................. 4
2.4 Climate and erosion .................................................................................................. 5
2.5 Exposure.................................................................................................................... 6
2.6 Coastline protection .................................................................................................. 7
3.0 Methodology................................................................................................................. 8
3.1 Geo-referencing Photos............................................................................................. 8
3.2 Coastline and riprap identification............................................................................ 8
3.3 Calculating area of eroded materials......................................................................... 8
3.4 Calculating area of materials deposited .................................................................... 9
3.5 Calculating erosion and deposition rate change per year.......................................... 9
3.6 Change in amount of riprap .................................................................................... 10
4.0 Results......................................................................................................................... 11
5. v
4.1 Erosion and deposition............................................................................................ 11
4.2 Change in rate of erosion and deposition................................................................ 12
4.3 Coastline and riprap ................................................................................................ 13
4.4 Lateral movement ................................................................................................... 13
4.5 1944 to 1954............................................................................................................ 14
4.6 1954 to 1965............................................................................................................ 17
4.7 1965 to 1976............................................................................................................ 19
4.8 1976 to 1983............................................................................................................ 21
4.9 1983 to 2002............................................................................................................ 23
4.10 2002 to 2012 ......................................................................................................... 25
5.0 Discussion................................................................................................................... 27
5.1 The impacts of riprap on coastal erosion................................................................ 27
5.2 Lateral movement ................................................................................................... 28
5.3 Sources of error....................................................................................................... 30
5.4 Recommendations................................................................................................... 31
6.0 Conclusion .................................................................................................................. 31
7.0 References................................................................................................................... 33
Appendix A: Project Proposal .......................................................................................... 35
6. vi
Appendix B: Mathematical Equations and Results .......................................................... 44
Appendix C: Coastline analysis ........................................................................................ 55
Appendix D: Tables of results .......................................................................................... 57
Appendix E: Coastline pictures ........................................................................................ 59
Appendix F: Pixel sizes .................................................................................................... 71
List of Figures
Figure 1: The coastline that is being analysed. Map modified from Service New
Brunswick. .......................................................................................................................... 2
Figure 2: The locations of Site A, Site B and Site C. Map modified from Service New
Brunswick. .......................................................................................................................... 3
Figure 3: Kouchibouguac Ecoregion. (New Brunswick Department of Natural Resources,
2007) ................................................................................................................................... 4
Figure 4: Area of materials eroded and deposited ............................................................ 11
Figure 5: Deposition rate change ...................................................................................... 12
Figure 6: Change in erosion rates ..................................................................................... 13
Figure 7: Lateral movement of the coastline .................................................................... 14
Figure 8: Coastlines from 1944 (red) to 1954 (yellow). ................................................... 15
Figure 9: Coastlines from 1944 (red) to 1954 (yellow) and Site A (yellow), B (green), and
C (red). .............................................................................................................................. 16
7. vii
Figure 10: Coastlines from 1954 (red) and 1965 (yellow). .............................................. 17
Figure 11: Coastlines from 1954 (red) to 1965 (yellow) and Site A (yellow), B (green),
and C (red). ....................................................................................................................... 18
Figure 12: Coastlines from 1965 (red) and 1976 (yellow) and riprap (black). ................. 19
Figure 13: Coastlines from 1965 (red) to 1976 (yellow) at Site A (yellow), B (green), C
(red) and riprap (black). .................................................................................................... 20
Figure 14: Coastlines from 1976 (red) and 1983 (yellow) and riprap (black). ................. 21
Figure 15: Coastline from 1976 (red) to 1983 (yellow) at Site A (yellow), B (green), C
(red) and riprap (black). .................................................................................................... 22
Figure 16: Coastlines from 1983(red) and 2002(yellow) and riprap (black). ................... 23
Figure 17: Coastline from 1983 (red) to 2002 (yellow) at Site A (yellow), B (green), C
(red) and riprap (black). .................................................................................................... 24
Figure 18: Coastlines from 2002(red) and 2012(yellow) and riprap (black). ................... 25
Figure 19: Coastline from 2002(red) to 2012(yellow) at Site A (yellow), B (green), and C
(red)................................................................................................................................... 26
List of Tables
Table 1: Coastline and riprap ............................................................................................ 13
8. viii
Executive Summary
The introduction of riprap along the coastline between East Point and Schooner Point,
near Miramichi New Brunswick, has disrupted erosion and deposition. Three specific
sites (Site A, Site B, and Site C) were identified along the coastline. Both Site A and Site
C have had no riprap structures along there coastlines while Site B was the first section of
the coastline to be riprapped between 1965 and 1976.
Historical aerial photographs and orthophotos were used to identify the effects that riprap
had on the coastline. ESRI ArcGIS was used to identify the position of the coastline at
the time when each photo was taken and measure the area of land eroded or deposited
between consecutive coastlines.
By 2012 over 89% of the coastline was riprapped and the rates of erosion along the
protected sections decreased by 37% between 1965 and 2012. Unprotected sections have
seen rates of erosion that were never experienced when the coastline was undeveloped
between 1944 and 1954. The rate of erosion at Site A increased by 5317% between 1983
and 2002 and at Site C, the rate of erosion increased by 2912% between 1965 and 1976.
When analysing the results it became apparent that many factors influence coastal erosion
and riprap has affected these rates.
The installation of riprap has not been effective at preventing erosion along protected
sections, only slowing erosion. Riprap installation has caused the unprotected coastline to
erode quicker than what might have occurred if the coastline was never riprapped.
9. 1
1.0 Introduction
Atlantic Climate Adaptation Solutions Association (2011) states that coastal erosion is a
natural weathering of rocks and sediments at the shoreline. This erosion can take place
both above and under the water. As shorelines erode, the coastline moves landward as a
result. This landward movement often threatens roads and infrastructure, buildings and
other coastal structures. In North East New Brunswick, the coastline is experiencing
erosion rates up to 1.2 meters per year (Government of New Brunswick, 2014).
Along the Schooner Point coastline, riprap was installed to protect properties from the
impacts of coastal erosion. This riprap only protected sections of the coastline that were
developed while undeveloped areas were left in their natural unprotected state.
Riprap can be effective at slowing the rate of erosion experienced along waterways and
along coastlines. Riprap is composed of large heavy stone blocks that interlock to
withstand the energy from waves; a sloping face with high permeability can absorb wave
energy while minimizing wave reflection and scour (Atlantic Climate Adaptation
Solutions Association, 2011). Protecting a section of coastline with riprap can influence
unprotected sections by causing erosion rates to increase and deposition rates to decrease.
The section of coastline in Schooner Point, near Miramichi New Brunswick, has sections
of coastline protected by riprap and non-riprapped sections. Riprap was installed on
various portions of this coastline a number of times between 1966 and 2012. The impact
of the installed riprap on the coastline between East Point and Schooner Point is currently
unknown.
This project shall analyze this section of coastline using historical aerial photos and
orthophotos to determine the impact that riprap has had on the natural erosion and
deposition processes. The impact of riprap on unprotected sections of the coastline will
be determined and recommendations regarding coastal erosion and riprap placement will
be made.
10. 2
2.0 Background
The section of coastline that will be analyzed in this project is located on the south side of
Miramichi Bay east of the former town of Chatham, NB. The analyzed section of
coastline starts at East Point extending to Schooner Point. Figure 1 is a location map that
indicates the section of coastline to be analyzed.
Figure 1: The coastline that is being analysed. Map modified from Service New
Brunswick.
Three sites were visually identified using aerial photos. The site locations (Site A, Site B,
and Site C) were chosen based on the presence or absence of riprap along the coastline.
The site locations are seen in Figure 2.
Site A and Site C are two sections of coastline that have never been riprapped
completely. The first section of coastline to be riprapped and has been riprapped a
number of times since 1976 was the coastline along Site B.
11. 3
2.1 Land use
Land along the coastline is divided into small lots that are used for summer cottages and
year round residences. Each lot has beach access and ocean views of Miramichi Bay.
Figure 2: The locations of Site A, Site B and Site C. Map modified from Service New
Brunswick.
2.2 Ecoregion
According to New Brunswick Department of Natural Resources (2007), the Schooner
Point area is part of the Eastern Lowlands Ecoregion. The ecoregion is comprised of a
large wedge of flat to gentle rolling terrain that starts near Bathurst in the northeast and
extends to Sackville in the southeast section of the province.
The New Brunswick Department of Natural Resources (2007) states that the land
immediately surrounding the Schooner Point area is part of the Kouchibouguac
Ecoregion.
12. 4
The Kouchibouguac Ecoregion extends from Miramichi Bay to Cape Tormentine along
the eastern coastline of NB; dominated by river estuaries, sand dunes, and peat bogs. The
Kouchibouguac Ecoregion is outlined by the solid black line in Figure 3.
Figure 3: Kouchibouguac Ecoregion. (New Brunswick Department of Natural Resources,
2007)
2.3 Site Geology
The bedrock of the Kouchibouguac Ecoregion is composed primarily of Pennsylvanian
grey and red sandstone, mudstone, and conglomerate (New Brunswick Department of
Natural Resources, 2007). The sediments in this area are lacustrine/marine deposits
(Department of Natural Resources and Energy, Minerals).
The long-term coastline recession rate along of cliffs composed of sandstone,
conglomerate and mudstone is generally less than 0.20 m/yr. but can be over 0.60 m/yr.
13. 5
depending on structure and exposure (D. Berube, personal communication, March 9,
2015).
2.4 Climate and erosion
Rising sea levels, wind and waves cause coastal erosion. As the sea level rises (SLR) the
coastline will tend to move landward. The Government of Canada (2014) states that
Atlantic Canada will experience:
more storm events
increasing storm intensity
rising sea level
storm surges
increased coastal erosion
increased flood events
Climate change is considered the primary reason for these weather related events. Sea-
level rise and armoured coastlines can cause a “coastal squeeze effect”. As the water
level rises, natural beaches, estuaries, and salt marshes have to move inward to survive
(Atlantic Climate Adaptation Solutions Association, 2011). If the coastline is armoured
using riprap these natural features will not move landwards and will be “squeezed”
between the coastline and the rising ocean causing them to become submerged.
According to Atlantic Climate Adaptation Solutions (2011), the main driving force of
coastal erosion is waves that also, contribute to coastal flooding events. During storms,
the Atlantic Coast can experience waves that have heights of 10 m or more. These wave
heights are becoming greater as climate change has caused the sea level to rise by 30 cm
in the past 100 years. This 30 cm rise does not have the same effect on waves in deep
water offshore as it does on waves in shallow water near shore. The increase in the depth
of water directly affects the height of waves breaking against a shoreline. Sea level rise
is predicted to be between 66 cm – 76 cm over the next 100 years. The chances of
coastal flooding will increase with SLR. The higher seas will reduce the amount of
14. 6
freeboard (space between the water’s surface and the top of the cliff) between the surface
of the water and the land’s surface.
Most shoreline protection is designed for current day-to-day wave heights; this does not
take into account sea level rise or an increase in storm intensity causing greater wave
heights (Atlantic Climate Adaptation Solutions Association, 2011).
Another factor that affects the rates of coastal erosion is storm surges. The National
Oceanic and Atmospheric Administration (2014) states that storm surges result from an
abnormal rise in water caused by a storm. When a storm surge combines with a normal
high tide the water level can rise up to 7 meters. Any land and riprap structure that is less
than 7 meters above sea level can be severly flooded and damaged by these storm surges.
Hurricanes that track northeastward of the United States coastline and become extra-
tropical when reaching Canadian water are the primary drivers of coastal erosion in
Atlantic Canada (Atlantic Climate Adaptation Solutions Association, 2011).
Atlantic Climate Adaptation Solutions Association (2011) states that shorefast ice and
sea ice also affect coastal erosion and deposition rates though this ice erosion is much
less significant than erosion caused by waves. Shorefast ice can also protect shorelines
from wind and wave energy preventing coastal erosion.
2.5 Exposure
The United States Environmental Protection Agency (2012) states that an estuary is a
sheltered body of water along the coast where fresh water from rivers and streams mix
with saltwater. Estuaries are influenced by tides but are protected from the full force of
wind by penninsulas and barrier islands.
The Miramichi Bay has a total of five islands at the mouth of the bay which shelter the
Schooner Point coastline from waves and wind that are generated in the Gulf of Saint
Lawrence. The five barrier islands are Egg Island, Bay Du Vin Island, Hay Island, Fox
Island and Portage Island. There are five rivers that drain into Miramichi Bay: Miramichi
15. 7
River, Bay Du Vin River, Bartibog River, Napan River and Black River as well as many
other smaller streams.
2.6 Coastline protection
Atlantic Climate Adaptation Solutions Association (2011) states that there are many
methods used to prevent erosion of the coastlines. Coastal protection is not used along
undeveloped coastlines and the erosion process is allowed to occur naturally. Protection
of developed coastlines requires protection due to the value of the land. Often the value
of the land justifies the cost of installing and repairing infrastructure. There are proactive
and reactive measures that can be taken in response to coastal erosion; riprap is a reactive
measure.
Riprap is often constructed to protect land surrounding infrastructure and buildings from
erosion. The riprap along the analysed coastline has been installed and maintained to
protect residential properties from erosion that was occurring in the past and is currently
occurring today. This is costly, as the stone used in riprap construction has to be
transported to the site, installed by qualified contractors and maintained. The riprap
structures should be designed by qualified coastal engineers and inspected by coastal
engineers at regular intervals after construction has been completed. (Atlantic Climate
Adaptation Solutions Association, 2011).
According to Atlantic Climate Adaptation Solutions Association (2011) there are four
methods that are used in response to coastal erosion:
1. Construct and maintain riprap along developed coastlines (Hold the Line)
2. Create a line of defensive structures offshore to prevent wind and wave energy
from eroding the shoreline (Advance the Line)
3. Develop a strategy to move buildings and infrastructure inland or prevent
development next to the coastline (Manage Realignment)
4. Take no action and let erosion occur naturally
16. 8
Currently along the coastline between East Point and Schooner Point, a “Hold the Line”
approach has been taken.
3.0 Methodology
The section of Schooner Point coastline was selected based on suggestions from
instructors in the Environmental Technology program familiar with the coastline. The
photos were visually geo-referenced in ArcMap before the coastline could be photo-
interpreted.
3.1 Geo-referencing Photos
Five aerial photos and two ortho-photos were acquired from DNR. Three black and white
aerial photos were taken in 1944, 1954 and 1965. The remaining two aerial photos taken
in 1976, 1983, and two ortho-photos from 2002 and 2012 are in color.
The photos were geo-referenced using ArcMap 10.2.2. The “geo-reference toolbar” was
used to “fit” the pictures to display and the “effects toolbar was used to change the
transparency and contrast of the photos to aid the geo referencing process. A minimum of
four control points that have an average root mean square (RMS) residual level below 4.0
were used for each individual photo to assure higher accuracy. The lower the residual
level, the more accurate the process of geo-referencing.
3.2 Coastline and riprap identification
Coastlines and riprap were visually identified for each photograph. A File Geodatabase
(FGB) was created to catalog the identified coastal features. The line of vegetation along
the coast was used to determine the position of the coastline. To identify riprap, a
separate line feature class was created for the areas of coastline that was riprapped in
each photo.
3.3 Calculating area of eroded materials
Erosion can cause the position of a coastline to move landward past the position of a
previous coastline’s position. To determine the area of coastline lost to erosion, a polygon
layer was used that outlined these eroded sections.
17. 9
The average area of land eroded is found using Equation 1. The letter “E” represents area
of land lost due to erosion in square meters (m2) per year, “A” indicates the area of land
lost due to erosion in square meters (m2) and “T” represents the number of years that
passed since the first photograph and the next photograph were taken.
E = A/T (1)
3.4 Calculating area of materials deposited
A polygon layer was created in to outline the area of deposition. If the position of the
coastline moved towards the ocean past its previous location, this was deemed deposition.
The total area of deposition per year was determined using Equation 2. The letter “D”
represents area deposited in square meters (m2) per year, “A” represents area of
deposition in square meters (m2) and “T” represents how many years has passed since the
previously determine coastline in years.
D = A/T (2)
3.5 Calculating erosion and deposition rate change per year
Erosion and deposition rate changes were calculated by comparing the amount of erosion
or deposition that occurred per year later to the amount of erosion or deposition per year
that occurred between 1944 and 1954. This provides a percent of change regarding
erosion or deposition for the analysed coastline and the three specific sites. Changes in
erosion rates were calculated using Equation 3.
ER% = {(E2 / E1) * 100} - 1 (3)
The change in the erosion rate is represented by “ER%”. The letter “E2” represents the
amount of erosion that occurred later in square meters per year and “E1” is the square
meters of erosion per year that occurred between 1944 and 1954.
18. 10
The change in deposition rate was found using Equation 4.
DR% = {(D2 / D1) * 100} - 1 (4)
Deposition rate change is represented by “DR%”, “D2” represents amount of deposition
that occurred at later dates, and “D1” represents the amount of deposition that occurred
between 1944 and 1954.
3.6 Change in amount of riprap
The amount of riprap installed during 1976 was used to calculate the difference of riprap
installed at later periods. The percentage of riprap installed was found using Equation 5.
RR% = (RR2/RR1) * 100 - 1 (5)
The difference for riprap installed along the coastline is represented by “RR%”, “RR2”
represents the amount of riprap that was installed between 1965 and 1976, and “RR1”
represents the amount of riprap installed along the coastline after 1976. This was not
done for Site A or Site C as no riprap was installed along those sections of coastline.
3.7 Average lateral movement of coastline
The average lateral movement of coastline was calculated using Equation 7. The result
indicates how far the coastline moved laterally; if the result was negative, the coastline
moved landwards otherwise the coastline moved away from land.
R = (D – E) / L /T (6)
The letter “R” represents average lateral erosion rate expressed in meters (m) per year,
“D” represents area of deposition in square meters (m2), “E” represents area of erosion in
square meters (m2), “L” represents the length of coastline in meters (m) and “T”
represents how many years passed since the previous coastline position.
19. 11
4.0 Results
The results of the coastline analysis, specific site location analysis and pictures of the
coastline during each period is discussed below. The mathematical equations used for
analysis is referenced in Appendix B.
Tables for the coastline and each site were generated indicating the number of years that
has passed between photos, the change in the coastline’s length, and the amount of riprap
that was installed.
Tables of the coastline and the sites analysis can be referenced in Appendix C. The tables
that the graphs and figures in the following sections are based upon can be referenced in
Appendix D. Larger pictures of the coastlines can be seen in Appendix E.
4.1 Erosion and deposition
The amount of land lost due to erosion along the schooner point coastline varies greatly
from photo to photo. Negative values are an indication of erosion and positive values
indicate deposition. The results of the analysis can be seen in Figure 4.
Figure 4: Area of materials eroded and deposited
-500.00
-400.00
-300.00
-200.00
-100.00
0.00
100.00
1944-1954 1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* Average
Coastline Site A Site B Site C
20. 12
The area of deposited and eroded materials were found using Equations 1 and 2
respectively. The values are expressed in square meters (m2).
4.2 Change in rate of erosion and deposition
The rate of deposition and erosion varied greatly between 1944 and 2012. The deposition
rate of change was calculated by comparing to the current rates of deposition for each
period to the rate of deposition that occurred between 1944 and 1954. The results
displayed in Figure 5 were calculated using Equation 4.
A positive value indicates and increase and a negative value indicates a decrease. The
rate of deposition only increased four separate times between 1944 and 2012. The
average deposition rate change compared to 1944-1954 is displayed in Figure 5.
Figure 5: Deposition rate change
Erosion rate change compared to 1944 - 1954 can be seen in Figure 6. These values were
calculated using Equation 3. There were only positive changes regarding erosion rates;
negative rates would be an indication of deposition.
-100%
0%
100%
200%
300%
400%
500%
1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* 1965-2012*
NOTE: The (*) indicates that riprap was installed along sections of the coastline.
Coastline Site A Site B Site C
21. 13
Figure 6: Change in erosion rates
4.3 Coastline and riprap
The Schooner Point coastline had no riprap installed along any section until the period
between 1965 and 1976. Seen in Table 1 is the length of the coastline, length of riprap,
percent of the coastline protected and increases regarding riprap for each series of photos.
The increases of riprap along the coastline was calculated using Equation 5.
Table 1: Coastline and riprap
4.4 Lateral movement
When the coastline was eroded or when deposition occurred, it moved laterally toward
the land because of erosion or away from land as the result of deposition. Negative values
in Figure 7 are the result of erosion while positive values are an indication of deposition.
0%
1000%
2000%
3000%
4000%
5000%
1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* 1965-2012*
NOTE: The (*) indicates that riprap was installed along sections of the coastline.
Coastline Site A Site B Site C
Years 1944-1954 1954-1965 1965-1976 1976-1983 1983-2002 2002-2012
Coastline length (m) 1118.39 1110.49 1126.01 1149.49 1190.07 1168.21
Riprap (m) 84.1 186.57 884.15 1039.46
Coastline Protected 7% 16% 74% 89%
Changes in RipRap 0% 122% 951% 1136%
22. 14
The lateral movement values were calculated using Equation 6. The values indicate
lateral meters of movement per year per meter of coastline.
Figure 7: Lateral movement of the coastline
4.5 1944 to 1954
Between 1944 and 1954 there was no riprap protecting the coastline and land,
development along the water was minimal. The coastline position in 1944 and 1954 is in
in Figure 8.
Between 1944 and 1954, the coastline gained 121.06 m2 of land which and 138.55 m2
was eroded. These two values were used as a basis to calculate the rates of erosion and
deposition that occurred at later periods. The areas that were eroded and or experienced
deposition from later periods were compared to the 1944 to 1954 rates to calculate rate of
change. The coastline lost 17.49 m2 more that was deposited translating to 0.02 m of
average lateral movement per year. This rate of lateral movement is below the average
0.50 m lateral movement experienced along coastlines in North Eastern New Brunswick.
-0.70
-0.50
-0.30
-0.10
0.10
0.30
0.50
0.70
1944-1954 1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* 1944-2012
Coastline (m) Site A (m) Site B (m) Site C (m)
23. 15
Figure 8: Coastlines from 1944 (red) to 1954 (yellow).
The three sites and their section of coastline are outlined in Figure 9. Outlined in yellow
is Site A, Site B is outlined in green and Site C is outlined in red. The area of land eroded
during this period at Site A was 1.20 m2 while 9.17 m2 was deposited, Site B lost 18.33
m2 and gained 0.77 m2 while Site C lost 0.57 m2 and gained 11.67 m2. Again, these
values were used as a comparison when determining future rates and amounts of erosion
and deposition at these sites.
Even though the vegetation along the bank was removed at Site A, it gained 7.98 m2
during this period. Since there were no coastal structures west of the site, which could
interfere with erosion, the sediment may have been deposited due to longshore transport.
The shoreline moved away from land at a rate of 0.07 m per year. When compared to the
average lateral movement of 0.02 m experienced along the coastline, this gain was
substantial, illustrating that erosion and deposition was occurring naturally at this time.
24. 16
Figure 9: Coastlines from 1944 (red) to 1954 (yellow) and Site A (yellow), B (green), and
C (red).
The amount of land lost at Site B is far greater than the amount lost at the other two sites.
The coastline along Site B lost 17.56 m2 and moved landward at a rate of 0.19 m a year
during this period. Even though this lateral rate is nine times greater than the coastal
average, it is still far below the average lateral movement rate experienced in North
Eastern New Brunswick.
During this time, Site C seen only 0.57 m2 erode and 11.21 m2 of land deposited. The
coastline moved away from land at a rate of 0.27 m per year, the largest amount of
seaward lateral movement seen during this period and third largest amount of lateral
movement that occurred between 1944 and 2012. It is very likely that the land eroded at
Site B was deposited at Site C because of their close proximity.
25. 17
4.6 1954 to 1965
Between 1954 and 1965, the roads known as East Point road and Schooner Point road
were constructed (originally one road as seen in Figure 10). There is also evidence of
vegetation being cleared along the coastline.
The coastlines from 1954 and 1965 are seen in Figure 10. Again, as in the previous
photo, there is no riprap installed along the coastline; erosion and deposition appear to be
occurring naturally.
Figure 10: Coastlines from 1954 (red) and 1965 (yellow).
Total land lost increased from 138.55 m2 (1944-1954) to 217.93 m2 while deposition
slightly decreased to 120.99 m2. The coastline lost 96.93 m2. As a result, the coastline
moved landwards at a rate of 0.09 m, four times greater than the previous calculated rate.
The coastlines from 1954 and 1965 along Site A, B, and C are found in Figure 11.
26. 18
A total of 48.54 m2 was eroded along Site A. This was a 3955% erosion rate increase
over the previous erosion rate from 1944 to 1954. In addition to the increased rate of
erosion, no deposition occurred. The shoreline moved at a rate of 0.48 m landwards; still
below the 0.50 m average shoreline retreat experienced in the region.
Figure 11: Coastlines from 1954 (red) to 1965 (yellow) and Site A (yellow), B (green),
and C (red).
The coastline along Site B had 13.66 m2 eroded away while 3.34 m2 of material was
deposited; 10.32 m2 shoreline was eroded. The coastline moved landward at a rate 0.11 m
per year per meter of coastline during this time.
No erosion occurred at Site C though 11.62 m2 of material was deposited. The deposited
amount was 0.52 m2 more than the previous amount of 11.10 m2 (1944-1954).A lateral
seaward movement rate of 0.29 m occurred which was the second time the coastline
moved away from land. After 1965, the coastline at Site C only moved landward. Before
27. 19
riprap was installed along the coastline between East point and schooner Point, the
coastline at Site C was continually moving seaward.
4.7 1965 to 1976
The coastlines from 1965 and 1976 and the 84.10 m section of riprap that was installed
can be seen in Figure 12.
Figure 12: Coastlines from 1965 (red) and 1976 (yellow) and riprap (black).
Between 1965 and 1976, 84.10 m of riprap was installed along the coastline at Site B.
This 84.10 m section of riprap covered 7% of the coastlines 1126.01 m length.
The coastline lost 165.30 m2 and gained 189.38 m2 of deposited material. Over this 12-
year period, the coastline gained 24.09 m2 more material than was eroded. This is the
only time that the coastline gained material. This is very likely due to the installation of
the riprap.
28. 20
The coastline along Site A did not erode but gained 53.31 m2 of material. These
deposited sediments caused the coastline to move seaward at a rate of 0.46 m a year. This
could be due to re-vegetation of the shoreline naturally occurring. The coastlines at each
site and installed riprap can be seen in Figure 13.
Figure 13: Coastlines from 1965 (red) to 1976 (yellow) at Site A (yellow), B (green), C
(red) and riprap (black).
The land eroded from Site B was 13.78 m2 while 7.04 m2 of land was deposited. It is
interesting to note that with the riprap installed, the site lost 6.74 m2 of land to erosion.
The actual rate of deposition dropped by 25% compared to the deposition that occurred
between 1944 and 1954. The rate of erosion increased by 813%. This increase in erosion
could be caused by presence of riprap along this section of coastline.
The coastline along Site C lost 17.05 m2 of materials. This is the first time more material
was lost than was deposited. The riprapped section of coastline at Site B ends directly
east of this site.
29. 21
4.8 1976 to 1983
The coastlines from 1976 to 1983 are seen in Figure 14.
Figure 14: Coastlines from 1976 (red) and 1983 (yellow) and riprap (black).
Between 1976 and 1983, only eight years passed; the shortest number of years between
the two photos. During this period, the coastline lost 485.63 m2; the largest amount of
land lost due to erosion between 1944 and 2012. The amount of material deposited along
the coastline was at its lowest point over these years; only 33.05 m2 of material was
deposited along the coastline. The coastline moved towards land at 0.39 meters per year;
the highest lateral rate of movement occurring between 1944 and 2012.
The amount of riprap increased from 84.1 m to 186.57 m. The riprap was installed along
16% of the coastline. This equaled a 122% increase of riprap present along the coastline
30. 22
compared to the amount installed between 1965 and 1976. Seen in Figure 15 are the
specific sites and their respective sections of coastline.
The rate of erosion along the coast increased by 251%, the highest increase from all
periods while the coastline seen a 73% rate of deposition decrease. This deposition
decrease was the first time it occurred and the highest of all subsequent periods.
Figure 15: Coastline from 1976 (red) to 1983 (yellow) at Site A (yellow), B (green), C
(red) and riprap (black).
During this time, Site A lost 58.82 m2 of land while no deposition occurred. The rate of
erosion increased by 4815%, the second highest rate to occur at the site between 1944
and 2012.
A small amount of deposition occurred at Site B equaling 2.23 m2 while 22.31 m2 of
material was lost. During this time, the coastline at Site B lost 20.07 m2 of material while
31. 23
the rate of erosion increased by 163% and the rate of deposition dropping by 81%. The
coastline moved landward at a rate at 0.20 m per year.
The coastline at Site C gained 9.06 m2, and lost 0.64 m2 of material. Overall, the coastline
accumulated 8.42 m2; this is the last time any material was gained at this site. The rate of
deposition dropped by 22% and the rate of erosion increased by 12% during this time.
The coastline moved towards the ocean at a rate of 0.21 m per year.
4.9 1983 to 2002
The greatest amount of time passed between the two photos analyzed in this section; 20
years. During this time, the length of riprap installed along the coastline increased to
884.15 m covering 74% of the coastline. The position of the coastline during this time
and riprap can be seen in Figure 16.
Figure 16: Coastlines from 1983(red) and 2002(yellow) and riprap (black).
32. 24
Between 1983 and 2002, 212.78 m2 of material was removed by erosion while 36.03 m2
of material was deposited along certain sections. The coastline lost 176.75 m2 of material
overall and moved landward at a rate of 0.15 m per year.
The highest amount of land loss occurred at Site A that lost 64.83 m2 of material along
the coastline; no deposition occurred at the site. The rate of erosion increased by 5317%
during this time when compared to the rate observed between 1944 and 1954. This was
the highest rate of erosion seen at any site at any time. The coastline retreat can be clearly
seen in Figure 17. The coastline retreated 0.62 meters per year; this is the highest amount
of coastal retreat observed between East Point and Schooner Point.
Figure 17: Coastline from 1983 (red) to 2002 (yellow) at Site A (yellow), B (green), C
(red) and riprap (black).
The smallest amount of coastal change occurred at Site B that lost 3.48 m2 of material
and gained 2.03 m2 of material, adding up to 1.45 m2 of material lost. The rate of
33. 25
deposition decreased by 81% and the rate of erosion increased by 163%. The coastline
along Site B moved landward at a rate of 0.05m per year.
The coastline at Site C lost 12.18 m2 of material, gaining none during this time. Because
of the lost material, the coastline retreated toward land at a rate of 0.22 m a year. The rate
of erosion was 2051% greater than what was seen along this section between 1944 and
1954.
4.10 2002 to 2012
By this time the only sections of coastline that did not have riprap was the sections of
coastline along Site A, Site C and at a small beach access road just west of Schooner
Point. The amount of riprap installed was 1039.46 m that covered 89% of the coastline.
Seen in Figure 18 is the coastlines at during this time.
Figure 18: Coastlines from 2002(red) and 2012(yellow) and riprap (black).
34. 26
The coastline saw the second greatest amount of land loss during this period, losing
221.57 m2 and only gaining 46.17 m2 of material. Overall, 175.40 m2 of material was
removed and the coastline retreated at a rate of 0.15 m per year. The rate of deposition
decreased by 62% and the rate of erosion increased by 60%.
The coastline along Site A lost 36.44 m2 of material and gained none. The coastline
retreated towards land at a rate of 0.30 m because of the erosion.
The rate of erosion at Site A was 2945% greater than the erosion that occurred along this
coastline between 1944 and 1954. The sites can be seen in Figure 19.
Figure 19: Coastline from 2002(red) to 2012(yellow) at Site A (yellow), B (green), and C
(red).
The amount of material lost at Site B was 9.14 m2 and material gained equaled 4.69 m2.
The total loss of material amounted to 4.44 m2 and the coastline move landward at a rate
35. 27
of 0.05 meters per year. The rate of erosion during this time was 509% greater than what
was observed during the period between 1944 and 1954.
The material removed along Site C was 15.69 m2 while no deposition was observed. The
rate of erosion increased by 2690% compared to the rate of erosion that occurred between
1944 and 1954. The coastline retreated at a rate of 0.03 m a year.
5.0 Discussion
Riprap and the impact that this type of seawall has on the Schooner Point coastline will
be discussed in the following subsections. Sources of potential error that may have
influenced the analysis of the coastline will be examined as well.
5.1 The impacts of riprap on coastal erosion
Between 1944 and 2012, the coastline between East Point and Schooner Point has
undergone many natural and manmade changes. The biggest change along the coastline
was the installation of riprap. Over 89% of the coastline has been armoured (protected) to
prevent erosion and protect coastal properties. The coastline has also been extensively
developed for residential use. Every residential property has a coastline that is protected
by riprap. This subsection will explore the direct connection between riprap, erosion and
deposition.
The rates of erosion, rates of deposition, and lateral movement changed extensively
between 1944 and 2012. Not all of these changes can be attributed to riprap as the ocean,
weather, land subsidence and SLR also influence coastal erosion rates. However, the
results do show that riprap has affected the coastal erosion process along this section of
coastline.
The Atlantic Climate Adaptation Solutions Association (2011) states that protecting one
portion of an eroding cliff coast can affect unprotected portions of coastline by increasing
the rate of erosion. Even though there are other factors to consider when determining
coastal erosion rates, the riprap at Site B appears to have affected the coastline along Site
C.
36. 28
Before riprap was installed between 1965 and 1976, Site B lost 17.56 m2 during the
period from 1944 to 1954 and lost another 10.32 m2 between 1954 and 1965. During
those two periods, the coastline was largely undisturbed by man; Site C gained 11.10 m2
and 11.62 m2 of material during the two periods respectively.
After Site B was riprapped between 1965 and 1976, Site C lost 17.05 m2 of material. The
coastal erosion was prevented from naturally occurring at Site B because of the riprap. As
such, there were no eroded sediments available to be deposited at Site C. During the same
period, 7% of the coastline was riprapped and gained 24.05 m2 of material.
The effect of riprap on erosion and deposition can also be seen at Site A. However, some
of the coastal erosion experienced there may have been influenced by other
environmental factors. The riprapping of the coastline decreased deposition and increased
erosion at this site. After 1976, the rate of erosion at Site A was significant and continued
to be for every period afterward. Between 1983 and 2002, the rate of erosion was 5317%
greater that the erosion rate experienced between 1944 and 1954. This huge jump appears
to have been partially caused by the 884.15 m of riprap that was installed on both sides of
Site A. As 74% of the coastline was riprapped, there was only 26% of the coastline not
protected, which would allow sediments to be eroded and deposited elsewhere.
5.2 Lateral movement
Natural Resources Canada (2011) states that riprap replaces a shoreline and protects the
shoreline’s position. As erosion is directly related to lateral movement, the riprap has
been effective at decreasing the amount of landward lateral movement. It should be noted
that the riprap did not stop the erosion process; only slowing the process.
The protection of the shorelines position is evident at site B. The coastline along Site B
retreated at a rate of 0.15 m per year between 1944 and 1965. After riprap had been
placed between 1965 and 1976, the landward movement rate decreased from 0.19 m
(1944-1954) and 0.11 m (1954-1965) to 0.08 m per year.
37. 29
Between 1976 and 1983, the lateral movement of the coastline increased to 0.20 m per
year. This was the highest level experienced at this site thought it was lower than the
coastline’s rate of 0.39 m per year. The shoreline did retreat quicker along the
unprotected coastline compared to the coastline at Site B. Weather conditions and other
environmental factors may have caused this retreat, not the installation of riprap. The
structural failure of the riprap along Site B, seen in Figure 15, may have caused the
coastline to retreat 0.20 m per year along that section. The coastline from 1983 moved
landward past the previous coastline from 1976 though it was riprapped showing that it
failed to protect the coastline’s position. At this same time, the coastline gained material
along Site C (possibly receiving material because of the riprap failure at Site B) moving
towards the ocean at a rate 0.21 m per year.
Natural Resources Canada (2011) states that shoreline protection such as riprap can fail
due to overtopping, flanking, scour or geotechnical instability. Anyone of these reasons
could be the cause of the riprap failure at Site B. Overtopping of the riprap caused by
tidal surges and waves would be a valid explanation because the vegetation line moved
landward behind the riprap as well.
According to Natural Resources Canada (2011), poorly designed riprap offers only short
term protection against erosion and can actually increase erosion. Also, more than one
property should be considered when protecting the shoreline; the entire coastal system
should be examined. This is clearly illustrated at Site A (the section of the coast that was
cleared for marine navigation and never riprapped). At Site A, between 1983 and 2002,
the rate of landward coastal movement increased to 0.62 m per year from 0.15 m per
year. The use of riprap and prevention of erosion along other sections of the coastline
appears to have caused this unprotected section of coastline to erode more quickly.
Overall, lateral movement decreased along the entire section of analysed coastline after
riprap was used to prevent erosion. Between 1983 and 2002, the lateral movement at Site
B (the first riprapped section) decreased to 0.02 m per year and was 0.05 m a year
between 2002 and 2012. Those two lateral movement rates are much lower than the rates
38. 30
before the coastline was protected; between 1944 and 1954 the rate was 0.19 m per year
and 0.11 m a year ocurred between 1954 and 1965. After 1983, no section of the
coastline moved towards the ocean.
The only section whose lateral movement increased during 2002 to 2012 was Site C. The
coastline retreated at a rate 0.30 m per year. At this time 89% of the coastline was
riprapped preventing erosion and deposition.
5.3 Sources of error
Many potential sources of error can occur when using aerial photos and orthophotos to
determine coastal erosion. The resolution of the pictures can cause distortion based on the
size of the pixels and influencing the accuracy of the geo-referencing process. The height
of the aircraft when the photos were taken, the aircrafts pitch or yaw, time of year, time
of day, color, and weather conditions can all cause errors. However, there are many
possible sources of error when photo interpreting this is the approved method used by
coastal geo-morphologists.
Resolution and pixel size is an inverse relationship; the higher the resolution the smaller
the size of the pixels. For example, the picture from 1944 had a pixel length of 0.8m;
therefore all measurements are only accurate to ±0.8m. The pixel size for all pictures can
be referenced in Appendix F. These inaccuracies only compound when determining area
of erosion or deposition.
The vegetation line was also obstructed by shadows, structures and vegetation in each
photo causing inaccuracies when determining the coastline. The black and white photos
had areas that were hard to distinguish due to the various shades of grey and the features
tended to blend into the surrounding area on the photo.
If the height of the plane was greater than normal a bigger area was photographed and the
pixels covered a larger area; this is noticeable when looking at the picture from 1976
having a pixel size of 1.0 m. The angle of the plane affected the line of sight as vegetation
obscured different features.
39. 31
Other potential sources of error that cannot be determined by looking at a photo is the
type of soil along the coastline, the soil’s structure, and if bedrock is exposed along the
cliff face.
The two photos taken in 1983 and 2002, covered a period of 20 years. During the 18
years that passed between the two photos, many land use activities as well as coastal
changes had occurred. The installation and maintenance of riprap that occurred during
this time may have been identified as deposition. This could have influenced the coastline
analysis.
5.4 Recommendations
To gain a more complete understanding of erosion and deposition along the Schooner
Point coastline; many other factors must be analysed. The exposure of the coastline to
wind and wave action, tidal forces, weather and climate, sediment budget, subsidence, as
well as soil structure and soil type should be analysed to better understand the impact that
riprap has had and will have.
Instead of continuing to use the “Hold the Line” approach to protect the coastline it may
be more cost effective to retreat from the coast than to try to install or maintain the riprap
structures. Riprap is only designed to last for 50 to 70 years. Since some of the properties
are very close to the coastline and there is very little development inland behind these
properties, a realignment approach should be considered in the future.
6.0 Conclusion
In conclusion, the coastline has undergone many natural and unnatural changes due to the
installation of riprap between 1944 and 2012. Though there are many factors to consider
when analysing coastal erosion and deposition not covered in this analysis; it is apparent
that riprap has had some impact on the section of coastline. The results of the
photointerpretation has shown that as more riprap was installed along the coastline the
rates of erosion increased at Site A and Site C while the rates of deposition decreased
along the entire section of coastline. The rate of erosion experienced by protected
sections of coastline decreased and was not prevented.
40. 32
Before riprap is installed along a section of the coastline, the entire coastal system should
be analysed to understand the impact the structure(s) may have on unprotected sections.
The riprap structures have protected properties by slowing the rate erosion while
unprotected sections eroded at much higher rates. Because riprap only slows erosion,
increases rates of erosion along unprotected coastlines and is only designed for 50 to 70
years requiring regular maintenance, a more economical approach would be to move
structures further inland rather than trying to maintain the current coastline’s position.
41. 33
7.0 References
Atlantic Climate Adaptation Solutions Association. (2011). Climate Change and
Shoreline Protection in Atlantic Canada. Retrieved from Atlantic Climate
Adaptation Solutions: http://atlanticadaptation.ca/node/318
Atlantic Climate Adaptation Solutions Association. (2011). Coastal Erosion and Climate
Change. Retrieved from Atlantic Climate Adaptation Solutions:
http://atlanticadaptation.ca/sites/discoveryspace.upei.ca.acasa/files/Coastal%20Er
osion%20and%20Climate%20Change.pdf
Department of Natural Resources and Energy, Minerals. (n.d.). Generalized surficial
geology map of New Brunswick. NR-8 (scale 1 : 500 000): Department of Natural
Resources and Energy, Minerals, Policy and Planning Division, 2002.
Government of Canada. (2014, 05 26). Chapter 4 - Atlantic Canada . Retrieved from
Natural Resources Canada:
http://www.nrcan.gc.ca/environment/resources/publications/impacts-
adaptation/reports/assessments/2008/ch4/10341
Government of New Brunswick. (2014). Coastal Erosion. Retrieved from Environment
and Local Government:
http://www2.gnb.ca/content/gnb/en/departments/elg/environment/content/climate
_change/content/climate_change_indicators/indicators/water/coastal_erosion.html
National Oceanic and Atmospheric Administration. (2014, 09 05). Storm Surge
Overview. Retrieved from National Hurricane Center:
http://www.nhc.noaa.gov/surge/
New Brunswick Department of Natural Resources. (2007). Our Landscape Heritage.
Retrieved from Government of New Brunswick:
http://www2.gnb.ca/content/gnb/en/departments/natural_resources/ForestsCrown
Lands/content/ProtectedNaturalAreas/OurLandscapeHeritage.html
42. 34
United States Environmental Protection Agency. (2012, March 6). Basic Information
about Estuaries. Retrieved from Water: Estuaries and Coastal Watersheds:
http://water.epa.gov/type/oceb/nep/about.cfm
43. 35
Appendix A: Project Proposal
1.0 Introduction
The North East region of New Brunswick is experiencing high erosion rates of 1.2 meters
per year (Government of New Brunswick, 2014). Riprap has been installed to prevent the
erosion of the coastline; which impacts tourism, infrastructure, and waterfront properties.
The purpose of this project is to determine the impact of seawalls on the natural erosion
process in the Schooner Point area of New Brunswick using historical data, photographs,
and ArcGIS.
This document outlines the purpose of the project, the schedule for the project, the
methods used to determine erosion rates and what is required to successfully complete
the project on schedule.
2.0 Project Definition
This project will identify seawalls and determine their impact on the erosional process on
the Schooner Point coastline using ArcGIS. To successfully complete this project;
orthophotos, aerial photos, and Arc GIS 10.2.2 will be used.
2.1 Purpose
The goal of the project is to identify seawalls and determine how they affected the
erosion of the coastline. The natural erosion of the coastline can impact waterfront
property in Schooner Point area, while the prevention of erosion using seawalls can lead
to habitat loss as well as increase the rate of erosion experienced by unprotected
coastlines.
2.2 Objectives
The goal of this project to identify the seawalls and determine erosional rates before and
after the installation of seawalls. To ensure the successful completion of this project the
following objectives are required:
44. 36
Identification of sea walls along the coastline using orthophotos, aerial photos and
ArcGIS 10.2.2 by March 28th, 2015.
Calculate amount of land lost due to erosion by April 18th, 2015
Determine the impact of seawalls on the unprotected Schooner Point coastline by
April 25th, 2015
Wall plate must be completed on June 20th, 2015
2.3 Scope
The scope of the project includes the identification of seawalls along the Schooner Point
coastline as well as analyzing their impact on the natural erosion process using
orthophotos, aerial photos and ArcGIS 10.2.2.
The stretch of coastline to be analyzed starts at East Point and continues until reaching
the tip of Schooner Point roughly 1km of coastline.
This project concerns the riprap installed from 1940 to 2015 and how riprap influences
coastal erosion by calculating the change to the erosion process on protected and
unprotected sections of coastline, as well as the geology of the 1 km stretch of coastline.
This project will not analyze the causes or prevention of sea level rise and storm events.
Identifying riprap barriers and calculating erosion rates will be accomplished using
orthophotos, aerial photos and ArcGIS. Inspecting the riprap/erosion on the ground will
not be part of this project.
3.0 WBS
Listed below is the steps that are required for the project to be completed successfully.
1. Determine the impact that seawalls have on erosion rates
1. Create a GIS layer indicating seawalls
a) Use ArcGIS 10.2.2 to analyze photos
i. Identify seawalls
ii. Geo-reference photos
iii. Purchase photos
45. 37
2. Determine amount of land lost due to erosion
a) Create a GIS layer indicating change to coastline
i. Identify vegetation along coastline
ii. Geo-reference photos
iii. Purchase photos
2. Write technical report
1. Format paper
2. Write introduction section
3. Write background section
a) Research Coastal Geology
b) Research Coastal Erosion and Deposition
c) Research riprap
4. Write methodology section
a) Write results section
i. Seawall/Coastline analysis
5. Write results section
6. Write discussion section
7. Write conclusion
8. Proof read and edit paper
3. Present applied project
1. Prepare applied project Power Point
4. Create wall plate
1. Export photos highlighting the seawalls and land lost due to erosion
4.0 Schedule, Gantt
The Gantt chart for the project can be seen below in Figure: 1. This Gantt chart is based
upon the project schedule that can be found in Appendix A-1.
46. 38
Figure-A 1: Project Gantt chart
5.0 Resources & Procurement
There are several resources needed to complete the project successfully. Table 1 below
provides information on what is needed and the procurement dates.
Table-A 1:Required resources and dates
6.0 Budget
The items that have to be bought are:
Five aerial photos at a cost of $12.00+HST each
Two orthophotos at a cost of $12.00+HST each
One 3 x 4 Wall plate at a cost of $120.00 including HST
1/15/15 3/6/15 4/25/15 6/14/15
4.0 Present applied
project PP
3.0 Create wall
plate
2.0 Write technical
report
1.2 Determine
amount of land…
1.1 Create a GIS
layer indicating…
1.0 Determine the
impact of…
Project Schedule
Required Resources Date Required Procurement
Orthophotos March-23-15 Download from GeoNB
Aerial Photos March-23-15 Purchase from Service New Brunswick
ArcGIS 10.2.2 March-23-15 Provided by the NBCC Environmental Technology program
3 x 4 Wall Plate May-29-15 Purchase from Taylor Imaging
47. 39
The total budget required for the project will be $220.00 including HST.
7.0 Project Stakeholders
The project stakeholders are Mr. Linwood Dunham and the NBCC Environmental
Technology program. The NBCC Environmental Technology program is responsible for
supplying the funds to acquire aerial photos and a licensed copy of ArcGIS 10.2.2.
8.0 Risk Management Plan
There are varieties of risks that can affect this project if they are not addressed
immediately and accordingly. The risks, their impacts, solutions and likelihood of
occurrence are listed in Table 2 at the top of the next page. The major risks that can have
a severe impact on this project involve the technology required to complete the various
stages.
9.0 Project Change Process
Problems that may affect the outcome or prevent the completion of the project or its main
objectives will be addressed accordingly. Requested changes will be recorded on the
project change form found in Appendix A-2. This change form will be completed by the
project manager, changes will be listed, impact on project will be determined and
required solutions will be suggested and noted. Linwood Dunham must approve changes
prior to any implementation of the change.
10.0 Assumptions
The following items are assumed true for the duration of this assignment:
Orthophotos will be available from Service New Brunswick
Aerial photos will be available from Service New Brunswick.
The Environmental Technology Program will cover the costs the aerial photos
and orthophotos
A licensed copy of ArcGIS 10.2.2 will be provided by the Environmental
Technology Program at the NBCC Miramichi campus
Sea walls can be identified using orthophotos, aerial photos and ArcGIS 10.2.2
48. 40
Land loss due to erosion can be calculated using ArcGIS 10.2.2
Land loss can be measured using ArcGIS 10.2.2
The aerial photos can be geo-referenced using man-made/permanent features in
ArcGIS 10.2.2
Table-A 2: Project risk management plan
Risk Probability Impact Solution
Required Orthophotos
are not available
Low Low
Analyze different section
of coastline
Hard drive malfunction
Low Severe
Back up project onto two
separate hard drives
every week and online
Aerial photos
unavailable
Moderate Low
Analyze different section
of coastline
ArcGIS freezing or
crashing
Moderate Low
Restart ArcGIS. Save
project to hard drive
every 15 minutes if
possible
Computer hardware
malfunction
Low Low
Replace hardware. Use
another computer.
Failure to identify riprap
due to shadows or
picture quality
Moderate Moderate Seek guidance from
Linwood Dunham.
11.0 Constraints
The constraints that may affect the successful completion of this project are:
Inability to geo-reference aerial photos
Inability to identify vegetation along coastline
Unable to calculate amount of land lost due to erosion
Unable to identify seawalls using orthophotos, aerial photos and ArcGIS
Project paper must be submitted by May 29th, 2015
Power Point must be presented on June 19th, 2015
Wall plate must be completed by May 29th, 2015
49. 41
12.0 References
Atlantic Climate Adaptation Solutions Association. (2011). Climate Change and
Shoreline Protection in Atlantic Canada. Retrieved from Atlantic Climate
Adaptation Solutions: http://atlanticadaptation.ca/node/318
Atlantic Climate Adaptation Solutions Association. (2011). Coastal Erosion and Climate
Change. Retrieved from Atlantic Climate Adaptation Solutions:
http://atlanticadaptation.ca/sites/discoveryspace.upei.ca.acasa/files/Coastal%20Er
osion%20and%20Climate%20Change.pdf
Department of Natural Resources and Energy, Minerals. (n.d.). Generalized surficial
geology map of New Brunswick. NR-8 (scale 1 : 500 000): Department of Natural
Resources and Energy, Minerals, Policy and Planning Division, 2002.
Government of Canada. (2014, 05 26). Chapter 4 - Atlantic Canada . Retrieved from
Natural Resources Canada:
http://www.nrcan.gc.ca/environment/resources/publications/impacts-
adaptation/reports/assessments/2008/ch4/10341
Government of New Brunswick. (2014). Coastal Erosion. Retrieved from Environment
and Local Government:
http://www2.gnb.ca/content/gnb/en/departments/elg/environment/content/climate
_change/content/climate_change_indicators/indicators/water/coastal_erosion.html
National Oceanic and Atmospheric Administration. (2014, 09 05). Storm Surge
Overview. Retrieved from National Hurricane Center:
http://www.nhc.noaa.gov/surge/
New Brunswick Department of Natural Resources. (2007). Our Landscape Heritage.
Retrieved from Government of New Brunswick:
http://www2.gnb.ca/content/gnb/en/departments/natural_resources/ForestsCrown
Lands/content/ProtectedNaturalAreas/OurLandscapeHeritage.html
50. 42
United States Environmental Protection Agency. (2012, March 6). Basic Information
about Estuaries. Retrieved from Water: Estuaries and Coastal Watersheds:
http://water.epa.gov/type/oceb/nep/about.cfm
Appendix A-1 Project Schedule
Task Start Dates End Dates Duration (Days)
1.0 Determine the impact of seawalls on the coastline 2015-03-21 2015-05-02 43
1.1 Procurement of Materials 2015-02-02 2015-02-27 26
1.1 Create a GIS layer indicating seawalls 2015-03-21 2015-04-25 36
1.2 Determine amount of land lost due to erosion 2015-03-29 2015-05-02 35
2.0 Write technical report 2015-01-30 2015-05-29 120
2.1 Format paper 2015-01-30 2015-02-01 3
2.2 Write introduction section 2015-02-01 2015-02-07 7
2.3 Write background section 2015-02-02 2015-04-09 67
2.4 Write methodology section 2015-03-21 2015-04-09 20
2.5 Write results section 2015-05-02 2015-05-08 7
2.6 Write discussion section 2015-05-02 2015-05-16 15
2.7 Write conclusion 2015-05-16 2015-05-23 8
2.8 Proof read and edit paper 2015-05-23 2015-05-30 8
3.0 Create wall plate 2015-05-17 2015-05-29 13
3.1 Export photos highlighting sea walls and land lost due to erosion 2015-03-21 2015-04-25 36
4.0 Present applied project PP 2015-06-19 2015-06-19 1
4.1 Prepare applied project Power Point 2015-05-30 2015-06-18 20
Schedule for Applied Project (How Seawalls Impact the Schooner Point Coastline Natural Erosion Process)
51. 43
Appendix A-2 Project Change Form
Change Approved or Declined: Date:
Decision made by who:
How will proposed changes be implemented:
Reasons for decision:
Buget Affected (Yes or No): If budget is affeted state why and by how much:
Other options if requested change is not feasible:
Recommendations:
Change Request Outcome
Priority (High, Medium, Low):
Reason for Change:
Impact of Ignoring Change:
Analyzing Change
Change to Project Scope:
Change to Project Objective:
Project Request Change Form
Change Request #: Requested By: Date Requested:
Description of Change
Requested Change:
52. 44
Appendix B: Mathematical Equations and Results
Average Coastline Erosion per Year (Equation 1)
| E = area eroded per year | A = area eroded | T = years passed |
E = A/T
Total Coastline
1944 – 1965: 1524.00 m2 / 11yrs = 138.55 m2 per year
1954 – 1965: 2615.10 m2 / 12yrs = 217.93 m2 per year
1965 – 1976: 1478.67 m2 / 9yrs = 165.30 m2 per year
1976 – 1983: 3885.07 m2 / 8yrs = 485.63 m2 per year
1983 – 2002: 4255.51 m2 / 20yrs = 212.78 m2 per year
2002 – 2012: 2437.24 m2 / 11yrs = 221.57 m2 per year
Site A
1944 – 1954: 13.17 m2 / 11yrs = 1.20 m2 per year
1954 – 1965: 582.43 m2 / 12yrs = 48.54 m2 per year
1965 – 1976: no erosion
1976 – 1983: 470.57 m2 / 8yrs = 58.82 m2 per year
1983 – 2002: 1296.56 m2 / 20yrs = 64.83 m2 per year
2002 – 2012: 400.84 m2 / 11yrs = 36.44 m2 per year
53. 45
Site B
1944 – 1954: 201.60 m2 / 11yrs = 18.33 m2 per year
1954 – 1965: 163.94 m2 / 12yrs = 13.66 m2 per year
1965 – 1976: 124.01 m2 / 9yrs = 13.78 m2 per year
1976 – 1983: 178.44 m2 / 8yrs = 22.31 m2 per year
1983 – 2002: 69.57 m2 / 20yrs = 3.48 m2 per year
2002 – 2012: 100.51 m2 / 11yrs = 9.14 m2 per year
Site C
1944 – 1954: 6.23 m2 / 11yrs = 0.57 m2 per year
1954 – 1965:
1965 – 1976: 153.461 m2 / 9yrs = 17.05 m2 per year
1976 – 1983: 5.09 m2 / 8yrs = 0.64 m2 per year
1983 – 2002: 243.63 m2 / 20yrs = 12.18 m2 per year
2002 – 2012: 173.74 m2 / 11yrs = 15.79 m2 per year
54. 46
The average area of deposition per year (Equation 2)
|D = area of deposition per year| A = area of deposition| T = years|
D = A/T
Total Coastline
1944 – 1965: 1331.65 m2 / 11yrs = 121.06 m2 per year
1954 – 1965: 1451.91 m2 / 12yrs = 120.99 m2 per year
1965 – 1976: 1704.46 m2 / 9yrs = 189.38 m2 per year
1976 – 1983: 264.42 m2 / 8yrs = 33.05 m2 per year
1983 – 2002: 720.451 m2 / 20yrs = 36.02 m2 per year
2002 – 2012: 507.83 m2 / 11yrs = 46.17 m2 per year
Site A
1944 – 1965: 100.91 m2 / 11yrs = 9.17 m2 per year
1954 – 1965: no deposition occurred
1965 – 1976: 479.83 m2 / 9yrs = 53.31 m2 per year
1976 – 1983: no deposition occurred
1983 – 2002: no deposition occurred
2002 – 2012: no deposition occurred
55. 47
Site B
1944 – 1965: 8.48 m2 / 11yrs = 0.77 m2 per year
1954 – 1965 40.08m2 / 12yrs = 3.34 m2 per year
1965 – 1976: 63.36 m2 / 9yrs = 7.04 m2 per year
1976 – 1983: 17.85 m2 / 8yrs = 2.23 m2 per year
1983 – 2002: 40.58 m2 / 20yrs = 2.03 m2 per year
2002 – 2012: 51.64 m2 / 11yrs = 4.69 m2 per year
Site C
1944 – 1965: 128.36 m2 / 11yrs = 11.67 m2 per year
1954 – 1965 139.42 m2 / 12yrs = 11.62 m2 per year
1965 – 1976: no deposition occurred
1976 – 1983: 72.44 m2 / 8yrs = 9.06 m2 per year
1983 – 2002: no deposition occurred
2002 – 2012: no deposition occurred
60. 52
The increase in the amount of riprap installed along the analysed coastline
(Equation 5)
RR% = (RR2/RR1) * 100 – 1
|RR% = riprap change| RR2 = length of riprap installed at a later date| RR1 = length of
riprap present in 1976|
Analysed Coastline
1965 – 1976: (84.10 / 84.10) * 100 – 1 = 0% change
1976 – 1983: (186.57 / 84.10) * 100 – 1 = 122% change
1983 – 2002: (884.15 / 84.10) * 100 – 1 = 1051% change
2002 – 2012: (1039 / 84.10) * 100 – 1 = 1136% change
The average lateral movement of the coastline (Equation 6)
R = (E/L) / T (NOTE: + = coastline moved away from land, - = coastline moved toward
land)
|R = average lateral rate of erosion| E = area eroded (m2)| L =coastline length| T = years|
Total Coastline
1944 – 1954: (1331.65m2 – 1524.00m2) / 1118.39m / 11yrs = -0.02 meters per year
1954 – 1965: (1451.91m2 – 2615.10m2) / 1110.49m / 12yrs = -0.09 meters per year
1965 – 1976: (1704.46m2 – 1487.67m2) / 1126.01m / 9yrs = 0.02 meters per year
61. 53
1976 – 1983: (264.42m2 – 3885.07m2) / 1149.49m / 8yrs = -0.39 meters per year
1983 – 2002: (720.45m2 – 4255.51m2) / 1190.07m / 20yrs = -0.15 meters per year
2002 - 2012: (507.86m2 – 2437.24m2) / 1168.21m / 11yrs = -0.15 meters per year
Site A
1944 – 1954: (100.91m2 – 13.17m2) / 117.47m / 11yrs = 0.07 meters per year
1954 – 1965: (0.00m2 – 582.32m2) / 101.48m / 12yrs = -0.48 meters per year
1965 – 1976: (479.83m2 – 0.00m2) / 115.59m / 9yrs = 0.46 meters per year
1976 – 1983: (0.00m2 – 470.57m2) / 108.96m / 8yrs = -0.54 meters per year
1983 – 2002: (0.00m2 – 1296.56m2) / 104.05m / 20yrs = -0.62 meters per year
2002 - 2012: (0.00m2 – 400.84m2) / 122.59m / 11yrs = -0.30 meters per year
Site B
1944 – 1954: (8.48m2 – 201.60m2) / 90.36m / 11yrs = -0.19 meters per year
1954 – 1965: (40.08m2 – 163.94m2) / 91.76m / 12yrs = -0.11 meters per year
1965 – 1976: (63.36m2 – 124.01m2) / 91.03m / 9yrs = 0.07 meters per year
1976 – 1983: (17.85m2 – 178.44m2) / 99.90m / 8yrs = -0.20 meters per year
1983 – 2002: (40.58m2 – 69.57m2) / 95.31m / 20yrs = -0.02 meters per year
2002 - 2012: (51.64m2 – 100.51m2) / 93.63m / 11yrs = -0.05 meters per year
62. 54
Site C
1944 – 1954: (128.36m2 – 6.23m2) / 41.41m / 11yrs = 0.27 meters per year
1954 – 1965: (139.42m2 – 0.00m2) / 40.00m / 12yrs = 0.29 meters per year
1965 – 1976: (0.00m2 – 153.46m2) / 39.72m / 9yrs = -0.43 meters per year
1976 – 1983: (72.44m2 – 5.09m2) / 40.50m / 8yrs = 0.21 meters per year
1983 – 2002: (0.00m2 – 243.63m2) / 54.57m / 20yrs = -0.22 meters per year
2002 - 2012: (0.00m2 – 173.74m2) / 51.73m / 11yrs = -0.31 meters per year
63. 55
Appendix C: Coastline analysis
Table C-1: Analysed section of coastline
Table C-2: Site A coastline Analysis
Years 1944-1954 1954-1965 1965-1976 1976-1983 1983-2002 2002-2012
No. of Years 11 12 9 8 20 11
Erosion (m2
) 1524.00 2615.10 1487.67 3885.07 4255.51 2437.24
Deposition (m
2
) 1331.65 1451.91 1704.46 264.42 720.45 507.86
Riprap (m) 84.10 186.57 884.15 1039.46
Erosion per year
(m2
) 138.55 217.93 165.30 485.63 212.78 221.57
Deposition per year
(m2
) 121.06 120.99 189.38 33.05 36.02 46.17
Changes In Erosion
Rates 0% 57% 19% 251% 54% 60%
Changes in
Deposition Rates 0% 56% -73% -70% -62%
Changes in RipRap 100% 122% 951% 1136%
Coastline length
(m) 1118.39 1110.49 1126.01 1149.49 1190.07 1168.21
Lateral movement
(+/- m) -0.02 -0.09 0.02 -0.39 -0.15 -0.15
Years 1944-1954 1954-1965 1965-1976 1976-1983 1983-2002 2002-2012
No. of Years 11 12 9 8 20 11
Erosion (m
2
) 13.17 582.43 470.57 1296.56 400.84
Deposition (m2
) 100.91 479.83
Erosion per year
(m
2
) 1.20 48.54 58.82 64.83 36.44
Deposition per year
(m2
) 9.17 0.00 53.31
Changes In Erosion
Rates 0% 3955% 4815% 5317% 2945%
Changes in
Deposition Rates 0% 481%
Coastline length
(m) 117.47 101.48 115.59 108.96 104.05 122.59
Lateral movement
(+/- m) 0.07 -0.48 0.46 -0.54 -0.62 -0.30
64. 56
Table C-3: Site B coastline analysis
Table C-4: Site C coastline analysis
Years 1944-1954 1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012*
No. of Years 11 12 9 8 20 11
Erosion (m
2
) 201.60 163.94 124.01 178.44 69.57 100.51
Deposition (m2
) 8.48 40.08 63.36 17.85 40.58 51.64
Erosion per year
(m
2
) 18.33 13.66 13.78 22.31 3.48 9.14
Deposition per year
(m2
) 0.77 3.34 7.04 2.23 2.03 4.69
Changes In Erosion
Rates 0% -25% -25% 22% -81% -50%
Changes in
Deposition Rates 0% 333% 813% 189% 163% 509%
Coastline length
(m) 90.36 91.76 91.03 99.90 95.31 93.63
Lateral movement
(+/- m) -0.19 -0.11 -0.07 -0.20 -0.02 -0.05
Years 1944-1954 1954-1965 1965-1976 1976-1983 1983-2002 2002-2012
No. of Years 11 12 9 8 20 11
Erosion (m
2
) 6.23 0.00 153.46 5.09 243.63 173.74
Deposition (m2
) 128.36 139.42 72.44
Erosion per year
(m
2
) 0.57 17.05 0.64 12.18 15.79
Deposition per year
(m2
) 11.67 11.62 9.06
Changes In Erosion
Rates 0% 2912% 12% 2051% 2690%
Changes in
Deposition Rates 0% 0% -22.40%
Coastline length
(m) 41.41 40.00 39.72 40.50 54.57 51.73
Lateral movement
(+/- m) 0.27 0.29 -0.43 0.21 -0.22 -0.31
65. 57
Appendix D: Tables of results
Figure 4 is based on Table D-1.
Table D-1: Area of material deposited and eroded along the coastline
Figure 5 is based on Table D-2.
Table D-2: Lateral movement of the coastline in meters per year
The determined depositional rate changes can be found in Table D-3.
Table D-3: Depositional rate changes
The determined rate change that erosion underwent can be found in Table D-4.
Years 1944-1954 1954-1965 1965-1976 1976-1983 1983-2002 2002-2012 Average
Coastline (m2
) -17.49 -96.93 24.09 -452.58 -176.75 -175.40 -149.18
Site A (m2
) 7.98 -48.54 53.31 -58.82 -64.83 -36.44 -24.56
Site B (m2
) -17.56 -10.32 -6.74 -20.07 -1.45 -4.44 -10.10
Site C (m2
) 11.10 11.62 -17.05 8.42 -12.18 -15.79 -2.31
Years 1944-1954 1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* Total
Coastline (m) -0.02 -0.09 0.02 -0.39 -0.15 -0.15 -0.13
Site A (m) 0.07 -0.48 0.46 -0.54 -0.62 -0.30 -0.23
Site B (m) -0.19 -0.11 -0.07 -0.20 -0.02 -0.05 -0.11
Site C (m) 0.27 0.29 -0.43 0.21 -0.22 -0.31 -0.03
NOTE: An asterisk (*) indicates riprap along coastline
Years 1944-1954 1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* 1954-2012
Coastline 0% 56% -73% -70% -62% -30%
Site A 0% 481% 96%
Site B 0% -25% -25% 22% -81% -50% -32%
Site C 0% 0% -22% -5%
66. 58
Table D-4: Erosional Rate Change
Years 1944-1954 1954-1965 1965-1976* 1976-1983* 1983-2002* 2002-2012* 1944-2012
Coastline 0% 57% 19% 251% 54% 60% 88%
Site A 0% 3955% 4815% 5317% 2945% 3406%
Site B 0% 333% 813% 189% 163% 509% 402%
Site C 0% 2912% 12% 2051% 2690% 1533%
