Evaluating Coastal Erosion Structures December 18Th, 2014
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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. -
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. -
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. -
Linktm Gabions and Mattresses Design Booklet
LinkTM Gabions and Mattresses Design Booklet www.globalsynthetics.com.au Australian Company - Global Expertise Contents 1. Introduction to Link Gabions and Mattresses ................................................... 1 1.1 Brief history ...............................................................................................................................1 1.2 Applications ..............................................................................................................................1 1.3 Features of woven mesh Link Gabion and Mattress structures ...............................................2 1.4 Product characteristics of Link Gabions and Mattresses .........................................................2 2. Link Gabions and Mattresses .............................................................................. 4 2.1 Types of Link Gabions and Mattresses .....................................................................................4 2.2 General specification for Link Gabions, Link Mattresses and Link netting...............................4 2.3 Standard sizes of Link Gabions, Mattresses and Netting ........................................................6 2.4 Durability of Link Gabions, Link Mattresses and Link Netting ..................................................7 2.5 Geotextile filter specification ....................................................................................................7 2.6 Rock infill specification .............................................................................................................8 -
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. -
Chapter 213 the Impacts of Shoreline Protection
CHAPTER 213 THE IMPACTS OF SHORELINE PROTECTION STRUCTURES ON BEACHES ALONG MONTEREY BAY, CALB^ORNIA GaryB. Griggs* James F. Tait* Katherine Scott* Abstract As a result of severe coastal storm damage in recent years along the California coast and the continuation of development and redevelopment in hazard prone oceanfront areas, large numbers of coastal protection structures have been built. This same trend has been observed on the Atlantic and Gulf coasts as well. At present, fully 12%, or 130 miles of California's 1100 miles of shoreline have been armored. As the number of structures and their coastal frontage has increased, concern along the California coast and elsewhere has arisen in regard to the impacts of these protective structures on the adjacent beaches. Three Atlantic coast states (Maine, New Jersey, and North Carolina) have responded to this concern by establishing state-level policy which prohibits construction of any new "hard" protective structures. Although considerable laboratory scale research has been carried out on this problem, field work has been extremely limited. A study along the central California coast was initiated in order to resolve some of the most critical questions regarding the impacts of protection structures on beaches. Based on 4 years of precise, biweekly, shore- based surveys in the vicinity of different types of seawalls along the shoreline of northern Monterey Bay along the central California coast, some consistent beach changes have been documented. All of the changes observed to date have been seasonal and are best developed in the fall and winter months during the transition from summer swell to winter storm conditions. -
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. -
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. -
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. -
Geotechnical Aspects of Seawall Stability with Climate Change
GEOTECHNICAL ASPECTS OF SEAWALL STABILITY WITH CLIMATE CHANGE Lex Nielsen WorleyParsons [email protected] Agustria Salim Pells Sullivan Meynink Doug Lord Coastal Environment Geoff Withycombe Sydney Coastal Councils Group Ian Armstrong Sydney Coastal Councils Group Introduction Existing seawalls and protection structures exist at many locations around the Australian coast where construction details are unknown and the capacity of the structures to withstand storms has not been verified. Seawall asset owners and managers (usually Local Councils) are faced with determining development applications in areas protected by such structures. Often, the responsibility, ownership and liability arising from these structures are not clear, with many structures constructed entirely or in part on Public Land. Frequently, there is conflict between the coastal managers and the community who have varying impressions of their effectiveness in providing protection and their impact on the public beach. This project has developed methods whereby the efficacy of existing seawalls may be determined. The project was undertaken by the Sydney Coastal Councils Group (SCCG) with funding provided by the Commonwealth Department of Climate Change and Energy Efficiency (DCCEE) through a Climate Adaptation Pathways (CAP) grant. The project was overseen by a National Reference Group comprising expertise from local government, state government, universities with coastal management expertise and industry specialists. Key elements of the project were as follows: Literature review of existing seawall types, remote sensing techniques, options for upgrading, certification requirements - Water Research Laboratory (WRL), University of NSW (UNSW). Geotechnical assessment of structure types and common failure modes - WorleyParsons. Economic aspects of the decision making process - Bond University under the direction of the Centre for Coastal Management (CCM) at Griffith University (GU). -
Harbor Protection Through Construction of Artificial Submerged Reefs
Harbor Protection through Construction of Artificial Submerged Reefs Amarjit Singh, Vallam Sundar, Enrique Alvarez, Roberto Porro, Michael Foley (www.hawaii.gov) 2 Outline • Background of Artificial Reefs • Multi-Purpose Artificial Submerged Reefs (MPASRs) ▫ Coastline Protection ▫ Harbor Protection • MPASR Concept for Kahului Harbor, Maui ▫ Situation ▫ Proposed Solution • Summary 3 Background First documented First specifically Artificial reefs in First artificial reef Artificial reefs in artificial reefs in designed artificial Hawaii– concrete/tire in Hawaii Hawaii – concrete Z- U.S. reefs in U.S. modules modules 1830’s 1961 1970’s 1985-1991 1991- Present • Uses • Materials ▫ Create Marine Habitat ▫ Rocks; Shells ▫ Enhance Fishing ▫ Trees ▫ Recreational Diving Sites ▫ Concrete Debris ▫ Surfing Enhancement ▫ Ships; Car bodies ▫ Coastal Protection ▫ Designed concrete modules ▫ Geosynthetic Materials 4 Multi-Purpose Artificial Submerged Reefs (MPASRs) Specifically designed artificial reef which can provide: • Coastline Protection or Harbor Protection ▫ Can help restore natural beach dynamics by preventing erosion ▫ Can reduce wave energy transmitted to harbor entrances • Marine Habitat Enhancement ▫ Can provide environment for coral growth and habitat fish and other marine species. ▫ Coral can be transplanted to initiate/accelerate coral growth • Recreational Uses ▫ Surfing enhancement: can provide surfable breaking waves where none exist ▫ Diving/Snorkeling: can provide site for recreational diving and snorkeling 5 MPASRs as Coastal Protection Wave Transmission: MPASRs can reduce wave energy transmitted to shoreline. Kt = Ht/Hi K = H /H t t i Breakwater K = wave transmission t Seabed coefficient, (Pilarczyk 2003) Ht= transmitted wave height shoreward of structure Hi = incident wave height seaward of structure. 6 MPASRs as Coastal Protection • Wave Refraction: MPASR causes wave refraction around the reef, focusing wave energy in a different direction. -
Storms and Coastal Defences at Chiswell This Booklet Provides Information About
storms and coastal defences at chiswell this booklet provides information about: • How Chesil Beach and the Fleet Lagoon formed and how it has What is this changed over the last 100 years • Why coastal defences were built at Chiswell and how they work • The causes and impacts of the worst storms in a generation booklet that occurred over the winter 2013 / 14 • What will happen in the future Chesil Beach has considerable scientific about? significance and has been widely studied. The sheer size of the beach and the varying size and shape of the beach material are just some of the reasons why this beach is of worldwide interest and importance. Chesil Beach is an 18 mile long shingle bank that stretches north-west from Portland to West Bay. It is mostly made up of chert and flint pebbles that vary in size along the beach with the larger, smoother pebbles towards the Portland end. The range of shapes and sizes is thought to be a result of the natural sorting process of the sea. The southern part of the beach towards Portland shelves steeply into the sea and continues below sea level, only levelling off at 18m depth. It is slightly shallower at the western end where it levels off at a depth of 11m. This is mirrored above sea level where typically the shingle ridge is 13m high at Portland and 4m high at West Bay. For 8 miles Chesil Beach is separated from the land by the Fleet lagoon - a shallow stretch of water up to 5m deep.