DOCSLIB.ORG

Coastal Management Strategies Why Do We Need to Protect Our Coastline?

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Coastal Management Strategies Why Do We Need to Protect Our Coastline? New Unit: Managing Coasts We are moving onto a new unit called ‘Managing Coasts’. This topic will cover processes and features of the UK coastline. L1: Features of different types of wave. L2 & 3: Different erosion processes and associated features. L4 & 5: Different depositional processes and associated features. L6: Coastal defences L7: UK Case study How can we protect our coastline? Learning Objectives: - To know about the different coastal management strategies Why do we need to protect our coastline? As Britain is an island we are extremely vulnerable to coastal erosion. The coastline needs to be managed in order to maintain a balance between the forces of nature and the demands of people. Our coastline is under threat from cliff collapse, erosion, weathering, flooding and future sea level rise. Many of our coastal towns are also tourist destinations, e.g. Blackpool, Brighton and Great Yarmouth. These locations are of high value to our economy. Many people also live on the coastline therefore how these areas are managed is incredibly important. Coastal management strategies. • There are 2 categories of coastal management – (1) hard engineering and (2) soft engineering. I think the difference between hard and soft engineering is: Task: Using the photographs below, write down what you think is the difference between hard and soft engineering. An example of a hard An example of a soft engineering strategy engineering strategy Coastal management strategies. Hard engineering: Soft engineering: Uses artificial (man-made) structures Works with the natural coastal processes, to control the forces of nature. and uses very little man-made interference. Task: Using the correct definitions above and the photographs on the next slide, complete the table below – write H (hard) or S (soft) Management strategy H/S managed retreat gabions beach replenishment groynes sea wall dune regeneration revetments rip-rap breakwater Coastal management strategies. gabions sea wall revetment groynes rip rap beach replenishment dune replenishment managed retreat offshore breakwater Coastal management strategies Task • Using the information on slides 10 – 17 to complete the table on the next slide. • Remember you don’t have to write everything that is on the slide! Write in your own words so that you understand it! Name What it does Cost Advantages Disadvantages Sletch Name What it does Cost Advantages Disadvantages Sketch Coastal management strategies - GABIONS These are rock-filled wire cages often stacked or built up as a wall. They absorb wave energy as they are permeable and so reduce erosion. Although not pretty, they are cheap and effective. A disadvantage is that they are not very strong. • Sometimes gabions are made from reclaimed material such as old railway lines and rock boulders. This could be seen as environmentally friendly as no new materials are being used. • Although they are cheap and absorb wave energy well, they look un-natural and could deter tourists. • In some locations, local rock is used to reduce the visual impacts. • Some people are worried about the risks of gabions, particularly if the mesh breaks, as the rocks could fall out. Coastal gabions defence Cost £100 / m Lifespan 30 – 40 years Coastal management strategies – DUNE REGENERATION Dune regeneration involves creating or restoring sand dunes. Marram grass is planted on sand dunes, which helps to stabilise them and trap sand to further build the sand dunes. The dunes then provide a barrier and absorb wave energy. • During dune regeneration the land needs to be carefully managed so that any new vegetation that is planted is protected from trampling by humans. This could involve temporarily fencing off the dunes or by providing wooden walkways. • This is a relatively cheap process and it helps to maintain a natural looking coastline. Some people do not like areas of sand dunes being fenced off. Coastal dune regeneration defence Cost £30 / m Lifespan 30 – 40 years Coastal management strategies – SEA WALL A permanent concrete wall built to reflect wave energy back out to sea, preventing erosion. Very expensive to build and requires costly maintenance. They can create a strong backwash which can erode and damage the wall. They also limit access to the beach for visitors and tourists. • Some sea walls are curved and some are straight walls. In some coastal locations they have steps at the bottom to further break up the wave energy. • They are effective at protecting the base of a cliff. They usually have a walk way along the top of them. • Sea walls don’t always look very nice which can impact on tourism. • Although they are costly, the benefits should outweigh the costs protecting people, property and conservation areas amongst other things. Coastal sea wall defence Cost £7000/m £1000 – 2000 for repair work Lifespan up to 100 years Coastal management strategies – GROYNES These are usually wooden (or concrete) fences built at right angles to the coast. They trap material being transported by longshore drift thereby allowing beaches to develop. • They are cheap to build however they prevent the movement of sediment and starve beaches further along the coast of sand and so can cause erosion problems elsewhere along the same coastline. • Relatively easy to build and are inexpensive in comparison to other coastal management strategies. • Easily broken especially in stormy conditions. • Some people don’t like the look of groynes and get frustrated having to climb over them. Coastal groynes defence Cost £1500/m Lifespan 30 – 40 years Coastal management strategies – BEACH NOURISHMENT Sand is taken from elsewhere and pumped onto the beach to increase its size. It tries to replace material lost to longshore drift. Large, wide beaches are very effective at reducing the energy of waves. • Creating beaches can generate tourism and it is fairly cheap. It does however need to be maintained regularly. • Beach nourishment can only be carried out when wave energy is low, otherwise the sand is transported away from the beach by the waves. • Beach nourishment could have a short lifespan (may have to be re-done every few months) if there is strong longshore drift removing sediment from the beaches. Coastal beach nourishment defence Cost £50/m Lifespan 6 – 12 months Coastal management strategies – RIP RAP (or rock armour) This defence comprises of boulders or concrete blocks. It is placed at the foot of cliffs or back of beaches. It works by absorbing wave energy and so reduces erosion. Although not pretty, they are cheap and effective. • The rocks / blocks are piled up along the shoreline to form a type of sea wall. • They are placed on top of each other and gaps are left between them which help to break up the wave energy. • Rocks such as granite and basalt are often used. • Tourists may be put off by the look of rock armour / rip-rap. It is visually not very attractive. In some locations they have tried to use rocks which are the same colour as nearby cliffs to look more environmentally sympathetic. Coastal rip rap defence Cost £1000/m Lifespan 100 – 500 years Coastal management strategies – REVETMENTS These are wooden or concrete slanted barriers built parallel to the coast. They are designed to absorb wave energy. They are cheaper than sea walls but are often viewed as ugly. They also make it difficult for visitors and tourists to access the beach and need periodic repairs. • Revetments are often permeable and have natural stones or concrete blocks inside. They break up and absorb wave energy. • In very stormy conditions the wooden slats can be broken therefore repairs would be needed. • Tourists may not like to see the revetments and some people see them as visually obtrusive. • Revetments can also make access more difficult depending on where they are built. Coastal revetments defence Cost £2000/m Lifespan 30 – 40 years Coastal management strategies – MANAGED RETREAT The controlled flooding of low-lying coastal areas. If an area is at high risk of erosion, managed retreat could be an option. It usually occurs where the land is of low value, for example farm land. • This is a cheap option compared to paying for sea defences. • Creates a salt marsh which can provide habitats for wildlife and a natural defence against erosion and flooding. • Salt marshes are diverse ecosystems supporting many species. • Land is lost as it is reclaimed by the sea. • Landowners need to be compensated - this can cost between £5,000 - £10,000 per hectare. Coastal managed retreat defence Cost varies Lifespan permanent Diamond nine Which methods do you think are effective at Most effective protecting the coastline? • Seawall • Revetments • Gabions • Rip rap • Groynes • Sand dunes • Beach replenishment • Managed retreat Least effective • Do nothing.
Load more

Recommended publications
  • Coastal and Delta Flood Management
    INTEGRATED FLOOD MANAGEMENT TOOLS SERIES COASTAL AND DELTA FLOOD MANAGEMENT ISSUE 17 MAY 2013 The Associated Programme on Flood Management (APFM) is a joint initiative of the World Meteorological Organization (WMO) and the Global Water Partnership (GWP). It promotes the concept of Integrated Flood Management (IFM) as a new approach to flood management. The programme is financially supported by the governments of Japan, Switzerland and Germany. www.apfm.info The World Meteorological Organization is a Specialized Agency of the United Nations and represents the UN-System’s authoritative voice on weather, climate and water. It co-ordinates the meteorological and hydrological services of 189 countries and territories. www.wmo.int The Global Water Partnership is an international network open to all organizations involved in water resources management. It was created in 1996 to foster Integrated Water Resources Management (IWRM). www.gwp.org Integrated Flood Management Tools Series No.17 © World Meteorological Organization, 2013 Cover photo: Westkapelle, Netherlands To the reader This publication is part of the “Flood Management Tools Series” being compiled by the Associated Programme on Flood Management. The “Coastal and Delta Flood Management” Tool is based on available literature, and draws findings from relevant works wherever possible. This Tool addresses the needs of practitioners and allows them to easily access relevant guidance materials. The Tool is considered as a resource guide/material for practitioners and not an academic paper. References used are mostly available on the Internet and hyperlinks are provided in the References section. This Tool is a “living document” and will be updated based on sharing of experiences with its readers.
    [Show full text]
  • GEOTEXTILE TUBE and GABION ARMOURED SEAWALL for COASTAL PROTECTION an ALTERNATIVE by S Sherlin Prem Nishold1, Ranganathan Sundaravadivelu 2*, Nilanjan Saha3
    PIANC-World Congress Panama City, Panama 2018 GEOTEXTILE TUBE AND GABION ARMOURED SEAWALL FOR COASTAL PROTECTION AN ALTERNATIVE by S Sherlin Prem Nishold1, Ranganathan Sundaravadivelu 2*, Nilanjan Saha3 ABSTRACT The present study deals with a site-specific innovative solution executed in the northeast coastline of Odisha in India. The retarded embankment which had been maintained yearly by traditional means of ‘bullah piling’ and sandbags, proved ineffective and got washed away for a stretch of 350 meters in 2011. About the site condition, it is required to design an efficient coastal protection system prevailing to a low soil bearing capacity and continuously exposed to tides and waves. The erosion of existing embankment at Pentha ( Odisha ) has necessitated the construction of a retarded embankment. Conventional hard engineered materials for coastal protection are more expensive since they are not readily available near to the site. Moreover, they have not been found suitable for prevailing in in-situ marine environment and soil condition. Geosynthetics are innovative solutions for coastal erosion and protection are cheap, quickly installable when compared to other materials and methods. Therefore, a geotextile tube seawall was designed and built for a length of 505 m as soft coastal protection structure. A scaled model (1:10) study of geotextile tube configurations with and without gabion box structure is examined for the better understanding of hydrodynamic characteristics for such configurations. The scaled model in the mentioned configuration was constructed using woven geotextile fabric as geo tubes. The gabion box was made up of eco-friendly polypropylene tar-coated rope and consists of small rubble stones which increase the porosity when compared to the conventional monolithic rubble mound.
    [Show full text]
  • Hooper Beach Dune Erosion Assessment Report
    Hoopers Beach Robe Dune Erosion Assessment Report Quality Information Document Draft Report Ref 2018-06 Date 17-10-18 Prepared by D Bowers Reviewed by D Bowers Revision History Revision Authorised Revision Details Date Name/Position Signature A 20-7-18 Draft report D Bowers/ Managing Director B 24-8-18 Draft Report D Bowers/ Managing Director C 17-10-18 Final Report D Bowers/ Managing Director 2 2018-06 Disclaimer The outcomes and findings of this report have in part been informed by information supplied by the client or third parties. Civil & Environmental Solutions Pty Ltd has not attempted to verify the accuracy of such client or third party information and shall be not be liable for any loss resulting from the client or any third parties’ reliance on that information. 3 2018-06 Table of Contents Quality Information 2 Revision History 2 Disclaimer 3 1. Background 5 2. Assessment Methodology 6 Site Inspection & Site Observations 7 Discussions with Key Stakeholders 14 Client 14 DEW 15 Coastal Processes 15 Reference Document Review 15 Wind Patterns 16 Waves 18 5.3.1 Swell Waves 18 5.3.2 Wind waves 18 Sea levels including storm surge and sea level rise 20 5.4.1 Existing Climatic Conditions 20 5.4.2 Future Climatic Conditions 21 2050 Projections 21 2100 Projections 22 Erosion 22 5.5.1 Coastal Erosion and Recession 22 Short-term Storm Erosion 24 5.5.2 Long Term Recession 24 5.5.3 Recession due to Sea Level Rise (future climate) 27 5.5.4 Total estimated coastal recession 28 5.5.5 Causes of Current Accelerated Dune Erosion 29 Coastal Hazards Risk Assessment 29 Coastal Hazards 29 6.1.1 Current Hazards & Risks (0-10 years) 29 6.1.2 Future Hazards & Risk (Beyond 10 years) 29 6.1.3 Likelihood Consequence & Risk Rating 30 Potential Management Options 30 Short Term Management Options 31 Long Term Management Options 31 7.2.1 Soft Engineering Options 31 7.2.2 Hard Engineering Options 32 Development Plan Provisions 35 Conclusions 36 Recommendations 38 Appendix A 39 4 2018-06 1.
    [Show full text]
  • 1 the Influence of Groyne Fields and Other Hard Defences on the Shoreline Configuration
    1 The Influence of Groyne Fields and Other Hard Defences on the Shoreline Configuration 2 of Soft Cliff Coastlines 3 4 Sally Brown1*, Max Barton1, Robert J Nicholls1 5 6 1. Faculty of Engineering and the Environment, University of Southampton, 7 University Road, Highfield, Southampton, UK. S017 1BJ. 8 9 * Sally Brown ([email protected], Telephone: +44(0)2380 594796). 10 11 Abstract: Building defences, such as groynes, on eroding soft cliff coastlines alters the 12 sediment budget, changing the shoreline configuration adjacent to defences. On the 13 down-drift side, the coastline is set-back. This is often believed to be caused by increased 14 erosion via the ‘terminal groyne effect’, resulting in rapid land loss. This paper examines 15 whether the terminal groyne effect always occurs down-drift post defence construction 16 (i.e. whether or not the retreat rate increases down-drift) through case study analysis. 17 18 Nine cases were analysed at Holderness and Christchurch Bay, England. Seven out of 19 nine sites experienced an increase in down-drift retreat rates. For the two remaining sites, 20 retreat rates remained constant after construction, probably as a sediment deficit already 21 existed prior to construction or as sediment movement was restricted further down-drift. 22 For these two sites, a set-back still evolved, leading to the erroneous perception that a 23 terminal groyne effect had developed. Additionally, seven of the nine sites developed a 24 set back up-drift of the initial groyne, leading to the defended sections of coast acting as 1 25 a hard headland, inhabiting long-shore drift.
    [Show full text]
  • Integrated Coastal Management Act: National Estuarine Management
    26 No.35296 GOVERNMENT GAZETTE, 4 MAY 2012 DEPARTMENT OF ENVIRONMENTAL AFFAIRS No. 336 4 May 2012 NATIONAL ENVIRONMENTAL MANAGEMENT INTEGRA TED COASTAL MANAGEMENT ACT, 2008 (ACT NO. 24 OF 2008) INVITATION TO COMMENT ON THE DRAFT NATIONAL ESTUARINE MANAGEMENT PROTOCOL I, Bomo Edith Edna Molewa, the Minister of Water and Environmental Affairs, hereby in terms of section 33 (2) read with section 53 of the Integrated Coastal Management Act, 2008 (Act No. 24 of 2008) publish for comment the draft National Estuarine Management Protocol. Interested persons and organizations are invited to submit written commen~ on the draft National Estuarine Management Protocol as follows: Written comments may be submitted to the Department by no later than 16h00 on 04 June 2012, by mail, hand, e-mail or telefax transmission. Please note that comments received after the closing date may not be considered. 1.1.1 By mail 1.1.2 By hand 1.1.3 By E-mail Subject: Draft National Subject: Draft National Estuarine Subject: Draft NatiQ!]al Eswarine Estuarine Management Protocol Management Protocol Management Protocol The Deputy Director -General The Deputy Director-General; [email protected] .za Department of Environmental Department of Environmental Affairs: Telephonic enquiries Affairs: Oceans & Coasts; P.O Oceans & Coasts; East Pier 2; East Pier Mr Ayanda Matoti: +27 21 819 2476 Box 52126; V& A Waterfront, Road; V&A Waterfront CAPE TOWN, 8002 CAPETOWN The draft protocol is also available for download from the Departmenfs webs"e, www.environment.gov.za BOMO EDITH EDNA MOLEWA MINISTER OF WATER AND ENVIRONMENTAL AFFAIRS STAATSKOERANT, 4 MEl 2012 No.
    [Show full text]
  • Preparing for Sea-Level Rise Through Adaptive Managed Retreat of a New Zealand Stormwater and Wastewater Network
    infrastructures Article Preparing for Sea-Level Rise through Adaptive Managed Retreat of a New Zealand Stormwater and Wastewater Network Rick Kool 1,2, Judy Lawrence 1,* , Martin Drews 2 and Robert Bell 3 1 New Zealand Climate Change Research Institute, Victoria University of Wellington, 6012 Wellington, New Zealand; [email protected] 2 Department of Technology, Management and Economics, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark; [email protected] 3 National Institute of Water and Atmospheric Research, 3251 Hamilton, New Zealand; [email protected] * Correspondence: [email protected] Received: 6 October 2020; Accepted: 16 October 2020; Published: 1 November 2020 Abstract: Sea-level rise increasingly affects low-lying and exposed coastal communities due to climate change. These communities rely upon the delivery of stormwater and wastewater services which are often co-located underground in coastal areas. Due to sea-level rise and associated compounding climate-related hazards, managing these networks will progressively challenge local governments as climate change advances. Thus, responsible agencies must reconcile maintaining Levels of Service as the impacts of climate change worsen over the coming decades and beyond. A critical question is whether such networks can continue to be adapted/protected over time to retain Levels of Service, or whether eventual retreat may be the only viable adaptation option? If so, at what performance threshold? In this paper, we explore these questions for stormwater and wastewater, using a dynamic adaptive pathway planning (DAPP) approach designed to address thresholds and increasing risk over time. Involving key local stakeholders, we here use DAPP to identify thresholds for stormwater and wastewater services and retreat options, and for developing a comprehensive and area-specific retreat strategy comprising pathway portfolios, retreat phases, potential land use changes, and for exploring pathway conflicts and synergies.
    [Show full text]
  • Climate-Driven Community Relocations in the Solomon Islands and Alaska Provide Insight for a 1.5 °C Future
    Regional Environmental Change https://doi.org/10.1007/s10113-017-1256-8 ORIGINAL ARTICLE Heading for the hills: climate-driven community relocations in the Solomon Islands and Alaska provide insight for a 1.5 °C future Simon Albert1 & Robin Bronen2 & Nixon Tooler 3 & Javier Leon4 & Douglas Yee5 & Jillian Ash6 & David Boseto7 & Alistair Grinham1 Received: 4 May 2017 /Accepted: 12 November 2017 # Springer-Verlag GmbH Germany, part of Springer Nature 2017 Abstract Whilst future air temperature thresholds have become the centrepiece of international climate negotiations, even the most ambitious target of 1.5 °C will result in significant sea-level rise and associated impacts on human populations globally. Of additional concern in Arctic regions is declining sea ice and warming permafrost which can increasingly expose coastal areas to erosion particularly through exposure to wave action due to storm activity. Regional variability over the past two decades provides insight into the coastal and human responses to anticipated future rates of sea-level rise under 1.5 °C scenarios. Exceeding 1.5 °C will generate sea-level rise scenarios beyond that currently experienced and substantially increase the propor- tion of the global population impacted. Despite these dire challenges, there has been limited analysis of how, where and why communities will relocate inland in response. Here, we present case studies of local responses to coastal erosion driven by sea- level rise and warming in remote indigenous communities of the Solomon Islands and Alaska, USA, respectively. In both the Solomon Islands and the USA, there is no national government agency that has the organisational and technical capacity and resources to facilitate a community-wide relocation.
    [Show full text]
  • New York State Artificial Reef Plan and Generic Environmental Impact
    TABLE OF CONTENTS EXECUTIVE SUMMARY ...................... vi 1. INTRODUCTION .......................1 2. MANAGEMENT ENVIRONMENT ..................4 2.1. HISTORICAL PERSPECTIVE. ..............4 2.2. LOCATION. .....................7 2.3. NATURAL RESOURCES. .................7 2.3.1 Physical Characteristics. ..........7 2.3.2 Living Resources. ............. 11 2.4. HUMAN RESOURCES. ................. 14 2.4.1 Fisheries. ................. 14 2.4.2 Archaeological Resources. ......... 17 2.4.3 Sand and Gravel Mining. .......... 18 2.4.4 Marine Disposal of Waste. ......... 18 2.4.5 Navigation. ................ 18 2.5. ARTIFICIAL REEF RESOURCES. ............ 20 3. GOALS AND OBJECTIVES .................. 26 3.1 GOALS ....................... 26 3.2 OBJECTIVES .................... 26 4. POLICY ......................... 28 4.1 PROGRAM ADMINISTRATION .............. 28 4.1.1 Permits. .................. 29 4.1.2 Materials Donations and Acquisitions. ... 31 4.1.3 Citizen Participation. ........... 33 4.1.4 Liability. ................. 35 4.1.5 Intra/Interagency Coordination. ...... 36 4.1.6 Program Costs and Funding. ......... 38 4.1.7 Research. ................. 40 4.2 DEVELOPMENT GUIDELINES .............. 44 4.2.1 Siting. .................. 44 4.2.2 Materials. ................. 55 4.2.3 Design. .................. 63 4.3 MANAGEMENT .................... 70 4.3.1 Monitoring. ................ 70 4.3.2 Maintenance. ................ 72 4.3.3 Reefs in the Exclusive Economic Zone. ... 74 4.3.4 Special Management Concerns. ........ 76 4.3.41 Estuarine reefs. ........... 76 4.3.42 Mitigation. ............. 77 4.3.43 Fish aggregating devices. ...... 80 i 4.3.44 User group conflicts. ........ 82 4.3.45 Illegal and destructive practices. .. 85 4.4 PLAN REVIEW .................... 88 5. ACTIONS ........................ 89 5.1 ADMINISTRATION .................. 89 5.2 RESEARCH ..................... 89 5.3 DEVELOPMENT .................... 91 5.4 MANAGEMENT .................... 96 6. ENVIRONMENTAL IMPACTS ................. 97 6.1 ECOSYSTEM IMPACTS.
    [Show full text]
  • The Effects of Urban and Economic Development on Coastal Zone Management
    sustainability Article The Effects of Urban and Economic Development on Coastal Zone Management Davide Pasquali 1,* and Alessandro Marucci 2 1 Environmental and Maritime Hydraulic Laboratory (LIAM), Department of Civil, Construction-Architectural and Environmental Engineering (DICEAA), University of L’Aquila, 67100 L’Aquila, Italy 2 Department of Civil, Construction-Architectural and Environmental Engineering (DICEAA), University of L’Aquila, 67100 L’Aquila, Italy; [email protected] * Correspondence: [email protected] Abstract: The land transformation process in the last decades produced the urbanization growth in flat and coastal areas all over the world. The combination of natural phenomena and human pressure is likely one of the main factors that enhance coastal dynamics. These factors lead to an increase in coastal risk (considered as the product of hazard, exposure, and vulnerability) also in view of future climate change scenarios. Although each of these factors has been intensively studied separately, a comprehensive analysis of the mutual relationship of these elements is an open task. Therefore, this work aims to assess the possible mutual interaction of land transformation and coastal management zones, studying the possible impact on local coastal communities. The idea is to merge the techniques coming from urban planning with data and methodology coming from the coastal engineering within the frame of a holistic approach. The main idea is to relate urban and land changes to coastal management. Then, the study aims to identify if stakeholders’ pressure motivated the Citation: Pasquali, D.; Marucci, A. deployment of rigid structures instead of shoreline variations related to energetic and sedimentary The Effects of Urban and Economic Development on Coastal Zone balances.
    [Show full text]
  • Coastal and Ocean Engineering
    May 18, 2020 Coastal and Ocean Engineering John Fenton Institute of Hydraulic Engineering and Water Resources Management Vienna University of Technology, Karlsplatz 13/222, 1040 Vienna, Austria URL: http://johndfenton.com/ URL: mailto:[email protected] Abstract This course introduces maritime engineering, encompassing coastal and ocean engineering. It con- centrates on providing an understanding of the many processes at work when the tides, storms and waves interact with the natural and human environments. The course will be a mixture of descrip- tion and theory – it is hoped that by understanding the theory that the practicewillbemadeallthe easier. There is nothing quite so practical as a good theory. Table of Contents References ....................... 2 1. Introduction ..................... 6 1.1 Physical properties of seawater ............. 6 2. Introduction to Oceanography ............... 7 2.1 Ocean currents .................. 7 2.2 El Niño, La Niña, and the Southern Oscillation ........10 2.3 Indian Ocean Dipole ................12 2.4 Continental shelf flow ................13 3. Tides .......................15 3.1 Introduction ...................15 3.2 Tide generating forces and equilibrium theory ........15 3.3 Dynamic model of tides ...............17 3.4 Harmonic analysis and prediction of tides ..........19 4. Surface gravity waves ..................21 4.1 The equations of fluid mechanics ............21 4.2 Boundary conditions ................28 4.3 The general problem of wave motion ...........29 4.4 Linear wave theory .................30 4.5 Shoaling, refraction and breaking ............44 4.6 Diffraction ...................50 4.7 Nonlinear wave theories ...............51 1 Coastal and Ocean Engineering John Fenton 5. The calculation of forces on ocean structures ...........54 5.1 Structural element much smaller than wavelength – drag and inertia forces .....................54 5.2 Structural element comparable with wavelength – diffraction forces ..56 6.
    [Show full text]
  • Four Strategies for Dealing with Sea Level Rise
    Sea level Rise Adaptation Tools and Resources Did you know….? Canada has the longest coastline in the world – approximately 151,019 miles (243,041.5 km) In British Columbia, 80% of population lives within 5 km from the coast. 59 municipalities out of 169 municipalities are coastal, 14 out 28 regional Districts contain coastal communities. The length of the coast is approximatively 29,000 km including the mainland and all islands from Haida Gwaii south to Vancouver Island and the Gulf Islands Coastal population: 3,500,000 Major ports: Metro Vancouver, Prince Rupert and Victoria In BC, the government is planning for Sea Level Rise (SLR) using this projected data: 0.5m sea level rise by 2050, 1m by 2100 and 2 m by 2200 BC communities won't be affected by sea level rise in the same way due in part to vertical land movement. The highest relative sea level rise is projected to occur in the Fraser low land, the southern part of Vancouver Island and the North Coast of British Columbia The greatest threat to communities along the coast besides sea level rise is storm surge flooding. Coastal communities are already dealing with extreme water levels. Four Strategies for dealing with Sea Level Rise Protect – advance or hold the line: Reactive strategy to protect people, property and Four Main Main ApproaFourea infrastructure – dikes, seawalls for example, to keep the shoreline at the same position. May be very expensive, have limited effectiveness on long term and may increase the level Four Main Approaches to Adaptation of erosion instead of addressing it.
    [Show full text]
  • Coastal Structures, Waste Materials and Fishery Enhancement
    See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/233650401 Coastal Structures, Waste Materials and Fishery Enhancement Article in Bulletin of Marine Science -Miami- · September 1994 CITATIONS READS 32 133 4 authors, including: K.J. Collins A. C. Jensen University of Southampton National Oceanography Centre, Southampton 66 PUBLICATIONS 1,195 CITATIONS 70 PUBLICATIONS 1,839 CITATIONS SEE PROFILE SEE PROFILE All content following this page was uploaded by A. C. Jensen on 19 December 2014. The user has requested enhancement of the downloaded file. BULLETIN OF MARINE SCIENCE, 55(2-3): 1240-1250, 1994 COASTAL STRUCTURES, WASTE MATERIALS AND FISHERY ENHANCEMENT K. J, Collins, A. C. Jensen, A. P. M, Lockwood and S. J. Lockwood ABSTRACT Current U.K. practice relating to the disposal of material at sea is reviewed. The usc of stabilization technology relating to bulk waste materials, coal ash, oil ash and incinerator ash is discussed. The extension of this technology to inert minestone waste and tailings, contam- inated dredged sediments and phosphogypsum is explored. Uses of stabilized wastes arc considered in the areas of habitat restoration, coastal defense and fishery enhancement. It is suggested that rehabilitation of marine dump sites receiving loose waste such as pulverized fuel ash (PFA) could be enhanced by the continued dumping of the material but in a stabilized block form, so creating new habitat diversity. Global warming predictions include sea It:vel rise and increased storm frequency. This is of particular concern along the southern and eastern coasts of the U.K. The emphasis of coastal defenses is changing from "hard" seawalls to "soft" options which include offshore barriers to reduce wave energy reaching the coast.
    [Show full text]