03/8583 coastline 2003-2 · european coastline - one of the most visible consequences of this...
TRANSCRIPT
LIVING WITH
COASTAL EROSION IN EUROPE
SEDIMENT AND SPACE FOR SUSTAINABILITY
RESULTS FROM THE
EUROSION
S T U DY
European Commission
3
COLOPHON
Editors:
Pat Doody, Maria Ferreira, Stéphane Lombardo, Irene Lucius, Robbert Misdorp, Hugo Niesing, Albert Salman, Marleen Smallegange
Design and production:
Van Rossum Rijgroep bv, SchiedamMay 2004
Cover:
From left to right: Costa da Caparica, Portugal (Photo: IHRH); Saint Quay, France (Photo: anonymous); Cap Blanc Nez, France (Photo: anonymous);Scheveningen, the Netherlands (Photo: Rijkswaterstaat).
Back:
From left to right: Wadden Sea, the Netherlands (Photo: Rijkswaterstaat); Malaga, Spain (Photo: anonymous); Birling Gap, UK (Photo: J. Menrath); South Kerry, Ireland (Photo: Marine Institute, Ireland).
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FOREWORD
The history of Europe has been marked by the continuous migration of itsinhabitants towards the coastal zones, which very often offered more favourableconditions for economic growth. Today, about 70 out of the 455 million citizens ofthe enlarged European Union, i.e. 16% of the EU population, live in coastalmunicipalities. This proportion keeps increasing.However, our coastal communities have clearly had an impact on the coastalenvironment. Generally speaking, economic activities imply a pressure on naturalareas, but in the case of coastal zones, there are also some specific environmentalissues. These include the proliferation of engineered frontage, the intensive use ofnatural shores for recreation and tourism, and the extraction of near-shore sandand gravel for construction purposes. These fulfil important ecological, societaland economical functions. The most important of these functions are theprotection of human assets against storm surges and salt water intrusion, theabsorption of land-based nutrients and pollutants drained by rivers to the sea,and the breeding and feeding of fishes, crustaceans and birds. To replace thesenaturally fulfilled functions would cost far more than future generations ofEuropean citizens could afford.Economic activities can also contribute to accelerated coastal erosion of the
European coastline - one of the most visibleconsequences of thisrelentless and silentdepletion of the coastalenvironment. Coastalerosion occurs when thesea encroaches upon theland as a result of wind,wave and tide pressure inconditions of poorsediment availability.Coastal erosion is a naturalprocess which has alwaysexisted and throughouthistory has helped to shapeEurope’s coastlines, butthere is now evidence thatthe current scale of coastalerosion is far from natural.In many locations, humanattempts to remedy thesituation, e.g by erectingbreakwaters, can actually
make the situation worse by causing more erosion further along the coastline. On the other hand, if nothing is done, human-induced coastal erosion will in thelong run jeopardise the ability of coastal zones to adapt to the effects of climatechange, notably sea level rise and the increased frequency or magnitude ofstorms.The EUROSION study, commissioned by my Directorate-General for theEnvironment following an initiative by the European Parliament, set out toquantify the status, impact and trends of coastal erosion in Europe and assessneeds for action at EU, Member State and regional levels. The findings and policyrecommendations of this study are reported in this publication. The EUROSION study concludes that efforts should be made to improve coastalresilience through improved sediment management and allocation of sufficientspace for coastal processes. I hope that EU Member States and regions will takethe EUROSION recommendations forward. For our part, the Commission will takethem into account when finalising its thematic strategy on soil, and in otherrelevant policy areas.
Margot WallströmCommissioner for the EnvironmentEuropean Commission
INTRODUCTION
The scale of the problem
All European coastal states are tosome extent affected by coastalerosion. About twenty thousandkilometres of coasts, corresponding to20% 1, face serious impacts in 2004.Most of the impact zones (15,100 km)are actively retreating, some of them inspite of coastal protection works (2,900km). In addition, another 4,700 kmhave become artificially stabilised.
The area lost or seriously impacted byerosion is estimated to be 15 km2 peryear. Within the period 1999-2002,between 250 and 300 houses had to beabandoned in Europe as a result ofimminent coastal erosion risk andanother 3,000 houses saw their marketvalue decrease by at least 10%. Theselosses are, however, insignificantcompared to the risks of coastalflooding due to the undermining ofcoastal dunes and sea defences. Thisthreat has the potential to impactseveral thousands of square kilometresand millions of people. Over the past50 years, the population living inEuropean coastal municipalities hasmore than doubled to reach 70 million
inhabitants in 2001 and the total valueof economic assets located within 500meters from the coastline hasmultiplied to an estimated 500-1000billion euros in 2000. Given thepredictions for climate change, theerosion and flood risk to urban,tourism and industrial facilities,agricultural lands, recreational areasand natural habitats increases everyyear. Studies for the UN-InternationalPanel for Climate Change estimate thatthe annual number of victims of actual
coastal erosion or flooding will reach158,000 in 2020, while half of Europe’scoastal wetlands is expected todisappear as a result of sea level rise. 2
The difficulty of reconciling the safetyof people and assets with the benefitsoffered by natural coastal processes hasbeen exacerbated in the past 15 yearsas a result of increasing capitalinvestments (in coastal defence) andfalling river discharges. The length ofnew engineered frontage has increasedby 934 kilometres. Of the 875 km newlyeroding coastlines (eroding in 2001 butnot in 1986) 63% is located less than 30kilometres from an engineeredfrontage. As for the 37% of remainingnewly eroding areas, they tend to havea higher density in areas where sealevel has risen by more than 20 cm inthe past 100 years and is likely to riseanother 80 cm this century.
The cost of mitigation actions isincreasing. In 2001, public expenditurededicated to coastline protection against the risk of erosion and floodinghas reached an estimated 3,200 millioneuros (compared to 2,500 million in1986 3). However, this expendituremainly reflects the need to protectassets at imminent risk of coastalerosion, and does not reflect the hiddencosts induced by human activities in thelong term. Earlier studies for the UN-IPCC estimate that the cost of coastalerosion will average 5,400 million europer year between 1990 and 2020. 4
What is coastal erosion ?
Coastal erosion is the encroachmentupon the land by the sea and ismeasured by averaging over a period,which is long enough, to eliminate theimpacts of weather, storm events andlocal sediment dynamics.
Coastal erosion results in threedifferent types of impacts (or risks): • loss of land with economical, societal
or ecological value • destruction of natural sea defences
(usually a dune system) as a result ofa single storm event, which in turnresults in flooding of the hinterland.
• undermining of artificial seadefences, potentially also leading toflood risk.
The processes of coastal erosion andaccretion have always existed andhave contributed throughout history to
shape European coastal landscapes,creating a wide variety of coastaltypes. Erosion of inland soils inducedby rainfall and movement alongriverbeds provides in some areasconsiderable amounts of terrestrialsediments to the coast. Thesesediments together with those derivedfrom coastal features (such as erodingcliffs and marine sand banks) provideessential material for the developmentof offshore reefs, mud flats,saltmarshes, sandy beaches, sanddunes, and transitional marshes. Inturn, these coastal habitats provide awide range of outstanding benefitsincluding locations for economic andrecreational activities, protection fromflooding in low lying areas, absorptionof wave energy during storm surges,reduction of eutrophication of coastalwaters, as well as nesting and hatchingof fauna species. Combating coastalerosion can therefore create newproblems elsewhere, depending on thetype of measures taken.
Coastal erosion is usually the result ofa combination of factors - both naturaland human induced - that operate ondifferent scales. Most important naturalfactors are: winds and storms, nearshore currents, relative sea level rise (acombination of vertical land movementand sea level rise) and slopeprocesses. Human induced factors ofcoastal erosion include: coastalengineering, land claim, river basin
regulation works (especiallyconstruction of dams), dredging,vegetation clearing, gas mining andwater extraction.
The EUROSION study
As an echo to the threats mentionedabove, both the European Parliamentand the European Commission havefelt the need to undertake a Europe-wide study meant to provide quantifiedevidence that coastal erosion in Europedoes constitute a problem of growingmagnitude that public authorities donot always succeed in containing,hence to assess the needs for action.The results of this two year study,named EUROSION and steered by theDirectorate General of Environment ofthe European Commission, have beenmade public in May 2004. These resultsconsist in:
• A cartographic assessment of theEuropean coasts’ exposure to coastalerosion, based on spatial data andGIS analysis.
• A review of existing practices andexperiences of coastal erosionmanagement at the level of local andregional authorities
• A set of guidelines to betterincorporate coastal erosion issuesinto environmental assessmentprocedures, spatial planning andcoastal hazard prevention, and intoregional and local informationdecision-support systems.
• A set of policy recommendationsmeant to improve coastal erosionmanagement in the future at theEuropean, national, regional andlocal level.
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Aerial photographs of Happisburg respectively in 1992,1999 and 2001. Cliff retreat can be easily detected inthe upper part of the pictures.
Geological Dept. Ravenna MunicipalityLido Adriano (Ravenna). In this picture, one can clearlysee that hotels have been built right on the beach,resulting in an increased need for coastal protection(here by breakwaters)
This map shows the location of the case studies reviewed inthe framework of EUROSION study, some with their erosionrate per year. The cases of Cyprus, Tenerife, Azores and French Guiana arenot displayed on the map.
Famous cliffs of Etretat (Higher Normandy) shaped by coastal erosion
1 Due to isostatic post-glacial rebound, Sweden and Finland are subject to uplift and relative fall of sea level so they arenot significantly affected by coastal erosion (with the exception of South-Sweden); If the relatively stable coastlines ofSweden and Finland are excluded the percentage of coasts affected by erosion amounts to 27.
2 Salman et al, Coastal Erosion Policies: Defining the issues. EUROSION Scoping Study, 2002. Figures derived from theGlobal Vulnerability Assessment. WL Delft Hydraulics / Rijkswaterstaat, 1993.
3 Results of EUROSION survey 2002; figures for 1986 are subject to uncertainties.4 Salman et al, Coastal Erosion Policies: Defining the issues. EUROSION Scoping Study, 2002. Figures derived from the
Global Vulnerability Assessment. WL Delft Hydraulics / Rijkswaterstaat, 1993.
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EUROSION FINDINGS
The combined effect of coastal erosion,infrastructure development and theerection of defences to protect themhave created, in many areas, a narrowcoastal zone. “Coastal squeeze” occursespecially in low-lying and inter-tidalareas, which would naturally adjust tothe changes in sea level, storms andtides, but cannot do so due to theconstruction of inflexible barriers suchas roads, dykes, urbanisations, leisureparks, industrial and other facilities.This causes a direct loss of natural
habitats. In areas where relative sealevel is rising or where sedimentavailability is reduced, there is afurther coastal squeeze resulting froma steepening beach profile andforeshortening of the seaward zones asillustrated in the figure below.
In spite of coastal erosion problemsand the increasing impacts of ‘coastalsqueeze’ on the ability of the coast tosustain human use, development pressures on the coast have not abated. The building of protectivestructures is still widely practised,threatening natural resources. This willresult in further reduction in the spaceavailable at the coastal margin both forhuman activity, the protection affordedby naturally functioning coastalsystems and the sustainableexploitation of natural resources.
In spite of clear evidence that humanactivities can increase coastal erosion,observations made at the level ofEUROSION case studies demonstratethat Environmental Impact Assessment(EIA) procedures have not been able tocontain the extent of coastal erosion.
The reasons for this are multiple:
• Considerable interventions affectingcoastal erosion processes have takenplace since the 1900s (1950s in thecase of river damming), that is to saywell before the existence of EIAregulations in Europe (in general inthe 1980’s). Many of theseinvestments are still “active” indisturbing sediment transportprocesses. River basin regulationworks, which disrupt the transport ofcoarse river sediments to the sea, cause an annual sediment deficitestimated at 100 million tons(source: derived from EUROSIONdatabase);
• Coastal erosion results from thecumulative impact of a wide range ofnatural and human-induced factors,none of which may be considered asthe single cause for erosion. This istrue for dams (each dam perhapsonly trapping a small proportion oftotal sediments); and for otherprojects related to industrialdevelopment, tourism (marinas,seafront rehabilitation), urbanisation,sand mining and dredging, andcoastal protection itself. In case anEIA is required for such projects,experience has shown that theirindividual impact on coastal erosionmay not be significant enough tojustify the integration of coastalsediment transport in the EIA;
• Large size projects, such as harbourextension, land reclamation forcreating wind parks or energyproduction plant do address coastalerosion processes within theframework of their EIA. However, itis quite common that the cost ofmitigation measures exceeds thewillingness - or the capacity - of theproject developer to pay for it. This isbest illustrated by the case of Aveirowhere the cost of annual sand by-passing has been deemed excessiveby the harbour authorities;
• EIA procedures are notsystematically applied to small andmedium size projects, though theymay, when taken together,exacerbate coastal erosion.
• Current national legislation on EIA donot prescribe any clear rules forpublic hearings, i.e. forcommunicating to and cooperatingwith local stakeholders, whenestablishing an EIA. In a number ofcountries (notably Italy, Portugal andSpain) EIA reports are released forcomments to the public at a very late stage of project development andonly for a short period. This wasfound to considerably hamper theintegration of local "knowledge" onpotential environmental damage –including damage due to coastalerosion - in project design;
The consequences of EIA limitations inaddressing coastal erosion properlyresult in a significant increase of costs(or at least risks) for society, in termsof habitat loss, loss of public facilitiesand invested capital, and cost ofmitigation measures.
The risk of coastal erosion at aparticular location is the result of theprobability (frequency) of coastalerosion events and of the impacts(capital investment or population in therisk zone). Current pratices observed inEurope reveal that the tax payer –through expenditures executed bypublic authorities - supports the majorpart of costs associated with coastalerosion risk. Almost no cases are foundwhere the parties responsible forcoastal erosion or the owners of assetsat risk were paying the bill.
Public expenditure dedicated tocoastline protection against the risk oferosion and flooding has reached anestimated 3,200 million euros in 2001.This amount covers both newinvestments made in 2001 (53%), costsfor maintaining existing protectionschemes and monitoring the coastline(38%), and provision for purchasingcoastal lands at risk (9%) . Though littledata exists on the contribution ofprivate funding to coastal erosionmanagement in European memberstates, it is highly probable that thiscontribution does not reach 10% of thepublic expenditure. Of the case studiesreviewed, only Denmark showed asignificant contribution from privateowners, in this case reaching up to 50%
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Urban sprawlalong the Dutchcoast. Urbanised areasappear in red.Courtesy:Rijkswaterstaat
SPOT ImageImage of SPOT satellite sho-wing the coastal morphologyof the Ebro Delta. Availablefrom Catalogue Sirius at SpotImage: http://sirius.spotimage.fr/
The figure depictsthe catchment ofthe Ebro river. Red trianglesrepresent thedams built alongthe river.Particularly dama-ging to the coastalsediment budgetare those damsbuilt in the down-stream part of thecatchment.
Finding 1: Shortage of coastal sediments and space results
into “coastal squeeze”
Urbanisation of the coast has turned coastal erosion from
a natural phenomenon into a problem of growing
intensity. In many coastal areas erosion problems are now
increased by human activities and artificially stabilised
seafronts are progressively encroaching on sedimentary
coastlines and cliffs. Dynamic ecosystems and their
undeveloped coastal landscapes are gradually
disappearing, and lack of sediment can be a major
contributory factor. In many places ‘coastal squeeze’
is the manifestation of this phenomenon.
A.M. Staceybuilding too close to the shoreline can result ina loss of the shoreline and most of its functions
A simple illustration of ‘Coastal squeeze’. Habitats are lostas a result of land claim, sea level rise or reduction insediment availability
Finding 2: Current Environmental Impact Assessment
(EIA) pratices do not address coastal erosion properly
Environmental Impact Assessment (EIA) procedures -
as implemented under the terms of the directive
85/337/EEC – have been insufficient in addressing the
impact of human activities, such as development, on
the wider coastal environment. Subsequently, the cost
of attempting to reduce coastal erosion has increased
considerably in relation to the assets requiring
protection. Consequently it has resulted in a need to
transfer the cost of coastal erosion mitigation measures
to such activities.
Finding 3:The risk of coastal erosion is supported
financially by the public at large
The cost of reducing coastal erosion risk is mainly
supported by national or regional budgets, hardly ever
by the local community and almost never by the
owners of assets at risk or by the party responsible for
coastal erosion.This is emphasized by the fact that
coastal erosion risk assessment has not been
incorporated in decision-making processes at the local
level and risk information to the public remains poor.
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of the overall cost of coastal protection.The contribution of the private sectorto coastal erosion management costsis not seen by private entrepreneurs astheir responsibility but as a businessopportunity. Only authorities ofmedium-to-large size harbourscontribute significantly to works tomitigate the impact of their activitieson coastal erosion.
Observations made at the local levelmake it possible to classify thebehaviour governing investment at riskalong the coast. Such behaviourincludes:
• An underestimation of hazardprobability. Some individuals mayperceive the probability that damagecaused to their property by coastalerosion is not sufficiently high toalter the decision to build or move toan alternative location. In practice, amajority of private owners havingexperienced such damage reporttheir lack of knowledge about therisks beforehand ( “I wish I hadknown…”) and often blame theauthorities that have allowed suchinvestments. Only few countrieshave institutionalized the assessmentand systematic mapping of risks asintegral part of spatial planningprocesses. Note that even wherethey exist, such risk maps are notsystematically made accessible tothe public.
• Short term horizons. Individuals andinvestors may have relatively shorttime horizons during which theywant to recover their investment.Even if the expected life of the houseis 40 or 50 years, the investor mayonly look at the potential benefits ofhis/her investment over the nexteight to ten years before resale. Theymay reason that they will not beresiding in the property for longerthan this period of time. This way ofthinking has prevailed along theMediterranean coast, where theprofit return period in the tourismsector generally does not exceed 10years.
• Expectation of public assistance.Individuals may have little interest inconsidering the risk level if they
believe that they will be financiallyresponsible for only a small portionof their losses should a hazard occur.In that respect, common practice inmost European countries has largelyshown this belief to be well founded.In a number of cases, public policyand funding are directed to threatenedproperty owners and by the empathytheir situation generates in the public at large. In other cases, publicauthorities may be held responsiblefor damage induced by coastalerosion because they grantedconstruction permits in areas at risk.
The use of public money to safeguardthe safety of people and economicinfrastructure does not pose a problemas such. However, it may bequestionable whether publicauthorities should bear the financialcost when others are responsible forcoastal erosion or where ownerschoose to live within areas at risk. Theopportunity to place the onus forcoastal defence in these circumstanceson the beneficiaries (the “polluterpays” principle) and investments atrisk must therefore be considered.
As of 2001, about 7600 kilometresbenefit from coastal erosion mitigationschemes, and 80% of these schemeshave been in place for more than 15years. Such mitigation schemes useand combine a wide range oftechniques and approaches whichinclude:
• hard engineering techniques, i.e.using permanent concrete and rockconstructions to “fix” the coastlineand protect the assets locatedbehind. These techniques - seawalls,groins, detached breakwaters, orrevetments - represent a significantshare of protected shoreline inEurope (more than 70%);
• soft engineering techniques (e.g.sand nourishments), building withnatural processes and relying onnatural elements such as sands,dunes, marshes and vegetation toprevent erosive forces from reachingthe backshore;
• realignment of assets, consisting inremoving or abandoning houses andother constructions from the erosion-prone areas.
Case studies reviewed by EUROSIONhave provided a range of experiencesin relation to the cost-effectiveness andenvironmental friendliness of suchprotection schemes. Major lessonslearnt from these are:
• Lessons learnt from hard protectiontechniques. Many hard constructionshave had positive effects only in ashort time and space perspective. Bydisrupting long-shore drift ofsediment transport, beaches locatedfurther down-drift of hardconstructions in many cases havebeen deprived of sediment and as aresult suffered from increasederosion. Vertical constructions suchas seawalls and bulkheads alsoincrease turbulence and sedimentscouring, which help to underminetheir own foundations. Particularlyillustrative of this are the seawalls ofPlaya Gross (built in 1900),Chatelaillon (1925), or De Haan(1930), which still continue toexacerbate erosion problems. As for groins, they are effective for alimited length of coast, but on thedowndrift side erosion oftennecessitates an extension of thegroin-field, resulting into a “domino”effect. Hard engineering also provedto have limited efficiency in the caseof protected cliffs, such as those ofVentnor on the Isle of Wight and inSussex. Here slumping of soft rockcliffs is the result of terrestrialprocesses such soil weathering(through water seepage), lubricationbetween geological layers anderosion by rainwater along streamsand gullies and does not justoriginate as a result of wave attack.
• Lessons learnt from soft protectiontechniques. Dune, beach and nearshore sand nourishments havearoused a tremendous enthusiasm inthe past 20 years. The enthusiasmgenerated lies in their ability tocontribute positively to safety as wellas to other functions such asrecreational, water purification (indunes) and ecological values. In thecase of the Netherlands, systematicdune, beach and foreshore nourishment has been successfullyapplied since 1990. Sandnourishment is particularlysuccessful wherever: 1) it is provenas an efficient safety measure; 2) it iscost effective and 3) it providesopportunities for other coastalfunctional uses. However, it is quitefrequent that these requirements arenot met and sand nourishments are
executed with only a limitedknowledge of coastal hydraulics. Badpractices of sand nourishmentsnotably include those cases wherethe availability of appropriatesediments for nourishment is notgaranteed (resulting in higher costs)or where dredging of sand hascaused irreversible damage to seagrass communities (e.g. Posidoniaalong Mediterranean Sea).
• Lessons learnt from managedrealignment. Since the early 1990s, a new approach to address coastalerosion has developed in Europe andconsists in abandoning lands at riskand relocating the assets furtherinland. Such an approach has beenimplemented in the UK (Essex andSussex) and France (Criel sur Mer).In those cases, cost benefit analyseshave demonstrated that the cost oftraditional protection would havelargely exceeded the value of assetsto be protected in the long term(over the life expectancy of theassets), making managedrealignment a more reasonableoption from a an economical point ofview. Furthermore, managedrealignment may constitute a soundenvironmental solution as clifferosion is not stopped and continuesto provide sediments further down-drift. Experience has also shown thatthe financial basis and timing of“compensation” are key to ensure abroad acceptance of managedrealignment in some areas.
These experiences demonstrate thelimits of piecemeal responses tocoastal erosion, and the need for theadoption of a proactive approachbased on planning, monitoring,evaluation, and ICZM principles.
Pieterjan van der HulstRoad damaged by coastal erosion on Isle of Wight
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Finding 4:Traditional approaches to counteract coastal
erosion may be counterproductive
Over the past hundred years the limited knowledge of
coastal sediment transport processes at the local
authority level has often resulted in inappropriate
measures of coastal erosion mitigation. In many cases,
measures may have solved coastal erosion locally but
have exacerbated coastal erosion problems at other
locations – up to tens of kilometres away – or have
generated other environmental problems.
F. SabatierSeries of groins along the coast of Camargue. In some places, the sea has almost breached the sand barrier
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• reluctance to release keyinformation. Poor access todocuments or datasets consideredimportant to decision making isreported by the vast majority of thelocal stakeholders interviewed. Oftenthe reluctance of the informationproducer to release his/herinformation has resulted inmisunderstandings and conflict.These feelings, which may beexaggerated in some cases (see nextpoint), can be verified for example inrelation to requests forEnvironmental Impact Assessment(EIA) reports. Here the experience ofthe EUROSION team, who made 78requests for EIA studies in 11European regions, suffered 71refusals (see also Finding 2).Surprisingly, such documents hadbeen cleared by public authoritiesand were meant to be accessible.
• poor archiving and disseminationcapacities. Delays in accessinginformation also originate in the lackof clearly established disseminationmechanisms such as informationresource centres, virtual libraries, orsimply contact persons for eachexisting datasets or documents. Withthe notable exception ofgovernmental bodies in charge of
producing and diffusing baselinedata over the whole national territory– e.g. national geological surveys,national meteorological centers,national mapping agencies,hydrographical offices and riverbasin agencies – other institutionsproduce data largely for their ownpurposes (be it research ormanagement oriented) and not forexternal users. Extending theirmandate to data disseminationwould require rethinkingorganisational issues, defining datadiffusion policies and most of allidentifying the economical incentiveswhich are currently not wellperceived by the data producers(especially publicly fundedproducers).
The above mentioned shortcomingsare emphasized by the fact that,contrary to other sectors (e.g. coastaldefence, land-use planning, watermanagement), the sector of coastalinformation management does notclearly fall under the responsibility ofany of the institutions existing at thenational or local level. Thisadministrative vacuum alsojeopardizes the emergence of a longterm vision to overcome theseshortcomings.
In spite of its importance forsupporting decision-making,information is generally not seen bypublic authorities in charge of coastlinemanagement as a strategic sector,which justifies major investments. Thisdoes not necessarily mean that thebudget dedicated to data collectionand analysis should be increased – italready reaches between 10 and 20% ofall expenses related to coastal erosionmanagement within the casesreviewed (between 320 and 640 MillionEuro extrapolated to all Europe).Instead, it suggests that authorities arereluctant to conduct the appropriatereforms in the fields of informationmanagement. Reforms would make itpossible in the long run to: (i) increasethe cost-effectiveness of decisionsmade in the field of coastlinemanagement and, (ii) to reduce andoptimise the expenditure related tocoastal data production andprocessing. Yet, evidence shows thatinadequate use of existing informationhas been responsible for considerableeconomic losses in Europe as illustratedby the case of Vale do Lobo orLacanau-Cap Ferret.
Although a wide range of stakeholdersare involved in coastline managementat all levels, the information needs arequite similar for most of thesestakeholders and most of Europeanregions surveyed by EUROSION, andcan be summarised as follows:
• the impact of human activities oncoastal sediment transportprocesses, which would make itpossible to optimise the selection ofsuitable sites for investments and/orto establish environmental liabilities;
• the delineation of areas at risk ofcoastal erosion for the coming years,which would make it possible toprioritise coastal erosion mitigationmeasures and control urbandevelopment;
• the long term costs and benefits ofcoastal erosion mitigation measures,which would make it possible toselect the most cost-effectivescenario and if needed proposeareas where retreat should bemanaged.
Paradoxically, these information gapscontrast with the tremendous amountof data available on near-shore areas(data being defined here as a"collection of raw measurements andobservations not collated intomeaningful information"). Thissuggests that information gaps mainlyoriginate as a result of organisationaland institutional shortcomings ratherthan technological limitations.investigations carried out byEUROSION at the level of Aquitaine,Catalunya, Isle of Wight, Essex, Aveiro,and North-Holland largely confirm thisconclusion and have identified anumber of shortcomings in coastalinformation management practices,which can be summarized as follows:
• a considerable fragmentation of datarepositories and host institutions.This aspect is all the more criticalsince rigorous risk and impactassessment, as well as land useplanning in coastal zones require awide variety of information involvingmany issues, wide time horizon andspatial scales. These include waveand wind climate, tidal regime, near-shore current patterns, history ofextreme water elevations, coastalgeology and geomorphology,sedimentary properties of theseabed, terrestrial and marinetopography, land use, and landtenure. Each host institution uses (ingeneral) its own standards, whichsignificantly increases the costs formaking the data interoperable anddelays the retrieval of data.
• duplication of data productionefforts. In a significant number ofcases, similar datasets have beencollated by different institutionsresulting in a considerableduplication of data acquisition costs.It is also quite frequent that two orthree departments of a sameinstitution finance, independentlyfrom other departments, theacquisition of the same data, whichresults in a considerable waste offinancial resources. This wasepitomized by the case of North-Holland. But lack of coordinationdoes not explain everything:excessive access fees to existingdata sources combined withrestrictive copyrights have also ledvarious stakeholders to develop theirown datasets.
Finding 5: The knowledge base for decision-making on
coastline management is weak, in general.
In spite of the availability of tremendous amount of data,
information gaps continue to exist.
The practice of coastal information management – from
raw data acquisition to aggregated information
dissemination - suffer from major shortcomings which
result in inadequate decisions. Surprisingly, sharing and
dissemination of coastal data, information, knowledge and
experiences are hardly ever considered by regional and
local stakeholders.
The use of a better knowledge base when coastal
development is proposed provides an opportunity, which
would reduce technical and environmental costs of human
activities (including measures for coastal erosion mitigation)
and could help anticipate future trends and risks.
Ile aux oiseaux - Arachon Basin
Germany’s northernmost outpost
Sylt is Germany’s northernmostoutpost, located in the GermanWadden Sea in the federal state ofSchleswig-Holstein. As a barrier island,the largest of the Fresian archipelago,Sylt consists of beaches and dunesbuilt against a residual core of glacialdrift deposits. The island Sylt alsoprovides many recreationalopportunities. Each year, the 40 kmlong west coast with its sandy beachesattracts about 600,000 tourists, whichmakes tourism, with its 5 million hotelnights spent on the island, the mainsource of income for the island.
A protected environment
In 1985, the region was designated asnational park (the Schleswig-HolsteinWadden Sea National Park) inrecognition of the high ecologicalsignificance of the Wadden Sea. Itserves, for example, as a place to feedand rest for migratory birds and is animportant nursery for many fish andcrustaceans. In 1999, an amendmentwas added to the law to enlarge theboundaries of the National Park westof the islands of Sylt and Anrum witha view to protect harbour porpoise –listed in Appendix II of the HabitatsDirective – and to create a whaleprotection area. Activities such ashunting, mussel fishery and boatingare severely controlled.
A dynamic coastline
The entire west coast of Sylt has beenseverely eroding for a long time, as aresult of strong exposure to frequentand heavy storm surges coming fromthe west. In addition, waves inducedby alternatively north westerly andsouth westerly winds generate a netlongshore transport which is directedsouthward in the south andnorthward in the north of Sylt. Thiscauses the island to bend as an arcand to grow both northwards andsouthwards. Moreover, the island issubmitted to changing conditions.While the average annual retreat atthe west coast from 1870 to 1950reached 0.9 metre per year, it hasincreased up to 1,5 metre per year in
SYLT – SCHLESWIG HOLSTEIN
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Lubos PolereckyDunes of Sylt
the past 50 years as a result of sealevel rise and warmer and stormierwinters. In the very south of Sylt,erosion devoured 15 metres of sandybeaches only in 2002.
Predictive models for the next fiftyyears have confirmed that erosionwill continue to affect the entire westcoast of Sylt and in particular thenorthern part of the island at Kampenand the southern part at Rantum andHornum. The central part of Sylt isexpected to remain reasonably stableprovided adequate protection isimplemented.
Working this nature
Past erosion mitigation strategies inSylt used to be based on hard coastaldefence works, including groins andconcrete seawall. These measuresproved to be counterproductive in thelong run since they contributed todisrupt longshore sediment transport,thus generating further erosion down-drift and other environmentalproblems. Moreover, the seawall atWesterland suffered from severedamage during storm surges as aresult of foreshore lowering in frontof the structure. This led regional andfederal authorities in the early 1970sto adopt new measures based onbeach nourishment and flexiblesolutions such as geotextile revetment.
This flexible measures did notcompletely dispel the need for hardprotection but contributed to improvetheir efficiency and life expentancy. In that respect, Sylt is quiteillustrative of successful beachnourishment schemes. The mainreason for this lies in the fact thatsediments with appropriatecharacteristics can be dredged at lowcost in the vicinity of Sylt and withoutirreversible impact on theenvironment. Moreover, lonsghoresediment transport rates remainwithin reasonable values, whichincreases the time interval betweentwo succesive nourishmentoperations (every 6 years on average)thus limiting impacts on theenvironment and cost.
Finally, by extending the width ofbeaches, sand nourishment iscompatible with tourism andrecreational activities, whichincreases its social acceptability bylocal population and balanceslimitations induced by the protectionof the Wadden Sea National Park.
Westerland resort on the western coast of Sylt
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HAUTE NORMANDIE
”La côte d’albâtre”: an outstanding
landscape in the service of the regional
economy
The white cliffs of Haute-Normandieextend from the Seine Bay to the southto the town of Ault-Onival along theFrench oriental Channel. These cliffshave been made famous all over theworld by the outstanding scenic beautyof Etretat located south of the coast.The dominant chalk substratum hasinspired the coast name – the “côted’albâtre” or the alabaster coast - andendows the region with atypical floraand fauna, including in particular typicalbird species attracted by the cliffcavities suitable for nesting. The PointeFagnet has been designated since 1990as a Special Protection Area (SPA)under the terms of the Bird Directiveand a significant part of the coast hasbeen proposed as sites of communityinterest for the Habitats Directive. As a consequence of this outstandinglandscape, the region captures asubstantial part of its income fromtourism and recreational activities. In1999, tourism reached 12 million hotelnights principally along the coast
Assets at risk
EUROSION has estimated that about180 km2 of areas of high ecologicalvalue lie within the radius of influenceof coastal erosion in Haute Normandy.Besides nature, cliff retreats alsodirectly affect houses located on thecliff top, most notably in themunicipalities of Criel, Quiberville andSaint-Pierre en Port. But this is not all:though dominated by natural areas and farmlands, the cliffs are locally cut by highly urbanised valleys perpendicular
to the coast - such as in Dieppe, Saint-Valery, Fécamp and Le Tréport – whichlie below the high water level duringspring tides. According to theEUROSION database, more than300,000 inhabitants are estimated tolive within the impact zone of coastalerosion and associated risk of flooding.This risk has become higher since theestablishment of two nuclear powerstations - Paluel and Penly – along theshoreline.
Causes of coastal erosion
The cliffs of Haute-Normandie haveretreated at an average rate of 20centimetres per year over the past 50years. This retreat takes the form ofcoastal landslide events which areresponsible, individually, for thecollapse of up to 10 metres of coastallands. Erosion results from bothmarine and continental processes: they are dominated by the assaults ofwestern waves and storms whichundermine the cliff stability, waterseepage from the top of the cliff whichdecreases the cohesion of the cliff rock,and the longshore drift whichtransports sediments – notably pebblesthat protect the cliff base from waveattacks – towards the North-East.
In the past 100 years however, coastalerosion has been exacerbated by humanactivities, notably the mining of pebbles,forbidden since 1972, and hard coastaldefence works such as groins andbreakwaters, which have disrupted thelongshore transport of pebbles, thatused to protect the base of the cliffsand the beaches of urbanized valleysdowndrift.
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Endangered houses in Criel-sur-Mer (Higher Normandy)- U.Dornbusch, University of Sussex, http://www.geog.sussex.ac.uk/BERM/
Addressing erosion issues
National and regional authorities haverecently realised that human activitiesand traditional approaches to managecoastal erosion – via groins andbreakwaters - have hadcounterproductive effects and reducedthe mobility of sediments along thecoast, which used to provide a naturalprotection to cliffs and urbanizedvalleys. This lesson has motivated theregional authorities of HauteNormandie and Picardie, which sharethe same coastal sediment cell, toestablish a partnership and to exchangeexperience with the view to addresscoastal erosion problems consistently.This partnership was initiated in theframework of the Contrat de PlanInterregional du Bassin Parisien (Paris Basin Interregional DevelopmentContract) and continued within theframework of the INTERREG IIprogramme “Beach erosion of theRives-Manche”. As a first step of thisinterregional cooperation, an assessmentof future erosion has been conductedbased on the analysis of historical andrecent aerial photographs.
This assessment is being followed bythe implementation of a coastalobservatory to become operational inthe second half of 2004. On themedium term, a better understandingof coastal erosion processes is expected
to improve decisions concerningshoreline management in HauteNormandie and adjacent regions.
Managed realignment in Criel sur Mer
The example of Criel sur Mer, locatedin the North-eastern part of the Côted’Albâtre, is quite illustrative of correctdecisions recently made in the fields ofcliff erosion management. In 1995, theFrench Government introduced newlegislation aimed at mapping thepotential extent of natural hazards and anticipating their impact (“Barnier Act”). Under the terms of thisnew act, the expropriation ofinhabitants living in areas at imminentrisk has become possible. Criel-sur-Merhas been among the first examples ofapplication of this measure in France.From 1995 to 2003, a total of 14 houseswere abondoned and their inhabitantsrelocated.
The originality of this expropriationprocess is that the indemnification ratedoes not reflect the real market value -which tends to decrease when the riskbecomes imminent - but was based on its “riskless” market value, whichpreserved the interest of relocatedfamilies. Cliffs continue to retreat andto provide valuable sediment to protect the valleys downdrift, andpeople remain safe.
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GULF OF RIGA
A natural and cultural heritage under
protection
The Gulf of Riga extends over 240 kmfrom the Cape Kolka in the northwestto Ainazi in the northeast. Four largerivers , as well as 140 small rivers andcreeks exit into the gulf. Along the gulf,sandy and boulder beaches, dunes,coastal forests, meadows, marshesand lagoons constitute the mostcommonly found habitats, which inturn shelter a large concentration ofwaterfowl in winter during moult andmigration, and a wide diversity of birdsin the breeding season. Beside nature,the gulf shores also host a largenumber of cultural heritage sites, inparticular the Daugavgriva fortificationinherited from the 17th century.
This natural and cultural heritage hasled the Latvian authority to designate astrip of 300 metres either side of thecoastline as a Coastal Protection Zone. Within this zone, clear-felling,excavations, building outside alreadyinhabited areas and any other activitywhich may adversely affect theprotective function of coastal habitatsare severely controlled.
A local economy oriented towards the
sea
Thirty towns and villages are locatedclose to the Gulf and notably in thesouth of the Gulf lies the capital Rigaand the resort of Jurmala that is visitedby up to 10 million tourists each year.Seven harbours are established alongthe gulf, among which is the harbourof Riga, whose freight traffic,principally composed of timber, oil andfertilizer products, reached 15 millionstons in 2001. Small-scale fisheriesoccur in the mouth of the Lielupe.
An increasing erosion risk due to a
changing environment
The last four decades witnessed changesof dynamic equilibrium conditions incoastal development of the Gulf ofRiga. Major among those changes arean increasing frequency of westernand northern storms as well as anincreased water discharge from therivers flowing into the gulf.
Both changes result in a significant riseof the mean sea level as measured bythe tide gauge of Daugavgriva. In turn, relative sea level rise is heldresponsible for a redistribution ofsediment cross-shore hence, a recession of sandy beaches anddunes which can reach up to two metresannually. Moreover, particularly strongcoastline erosion in the last decadeoccurred during extremely severe stormevents of 1992 and 2001 which usuallyoccur with a 100 year return period. In particular, erosion of 20 to 30 metresduring a single event has beenrecorded along the urbanized beach ofJurmala and Riga.
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In addition, the damming of the Daugavariver and dredging of the Lielupe riverbed for construction purposes sincethe 1930s have drastically reduced theamount of river sediments reaching theGulf of Riga and caused further retreatof foreshore and beaches in the vicinityof Riga and Jurmala.
A number of houses adjacent to theforedune in Jurmala and to theharbour facilities at Ziemas osta in Daugavgriva have been abandonedas a result of shoreline recession. Inother districts of Jurmala and Riga,erosion of beaches threatenseconomical assets associated withleisure facilities. Recent studies haveevaluated that up to three million eurosof capital are at direct risk of coastalerosion in Riga. However, this is nothing compared tothe potential damages of extremestorm surges as witnessed by thecoastal flooding of 2001 whichbreached the Daugavgriva foredune inNovember 2001, and inundated thehinterland.
Relative protection combining different
techniques
Latvian authorities have developed anapproach based on a combination ofdifferent measures. Replanting offoredunes with marram grass andwillows, as well as maintenance ofpine forest plantations constitute themain technical measures to slow downthe shoreline recession over the majorpart of the Gulf of Riga. Along the urbanised and industrialisedfrontage of the gulf, hard revetmentand submerged nourishment aredeemed to provide an immediate
protection to coastal assets. However,experience has shown that thisprotection is relative as witnessed bythe storm event of 2001 which haspartly destroyed hard revetments atZiemas osta and washed away 300,000euros of artificially nourished beaches.
Future perspectives
In spite of its legislation on coastalprotection, effective shorelinemanagement along the gulf of Rigasuffers an overlap of responsibilitiesamong national and local institutionsand from conflicts with other existinglegislation. In the future, reinforcedspatial planning regulations areexpected to better control thedevelopment of assets along the coastand to clarify the responsibilities of thevarious stakeholders towards coastalerosion and associated risk of flooding.This is expected to be achieved inconnection with the implementation ofthe ICZM Recommendations by theLatvian government.
Foto J.Vitins , A.Asars, JVKAerial photograph of Riga and the Daugava river mouth.
Alise TumaneDune erosion along the Gulf of Riga
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ESSEX ESTUARIES
A coastal county at the door of London
The County of Essex is in the south-east ofEngland and lies just to the north-east ofLondon. The coastline around its south-east edge is deeply indented, but flat, dueto several river estuaries enclosedbetween those of the river Stour to theNorth and the river Thames to the South.Essex has always been an agriculturalcounty, with a clay based but fertile soiland superb grain growing countryside –the subsequent grain giving rise toassociated milling, malting and brewingindustries. Livestock is common as well.Plant nurseries and market gardens aboundwhere the clay soil is covered by lighter,more fertile soils. The coastline has alsobrought great wealth, with importanttrading, fishing and shipbuilding centres.Sea salt from Maldon, oysters fromColchester and cockles at Leigh-on-Sea arefamous nation-wide. Today Essex is hometo Tilbury Docks, the Port of Harwich andBradwell Power Station. Its area is 3672 km2, and its population around 1.5 million.
Coastal lowlands challenged by the sea
Extensive areas of salt marshes, mudflatsand offshore sand banks fringe the Essexcoast. The area also includes grazing marsh,small areas of shingle shore, as well ascoastal cliffs to a smaller extent. Landwardareas are low-lying and mainly dedicatedto agriculture. Much of these areas areprotected from inundation from the sea byearth, sea walls and concrete embankments.Seaward of the seawall are large areas ofsalt marsh which flood on high tides andprovide a form of protection from waveattack. Essex is one of the most threatenedareas with respect to coastal flooding inEngland. For the whole country, over 1,8million residences and 180,000commercial properties are considered atrisk, potentially 5 million people, and 1,4million hectares of agricultural landincluding 61% of the total of grade 1 landin England and Wales.The total value ofthe assets at risk is estimated to be over350 billion Euro for England.
All the estuaries show signs of erosionand from North to South there appears tobe a general decline in beach levels. This is most noticeable in the salt marshes.In the North this is attributed to the poor
supply of material from the north with theapproaches to Harwich Harbour forcing thematerial seawards. The loss of saltmarshesin south east England has been subject toa considerable amount of research. Lossesdue to enclosure and subsequent use foragriculture amounted to some 4,340 ha.
Accelerated sea level rise: a new threat ?
Beside its exposure to coastal erosionprocesses – either nature or human driven- Essex has to face another threat. Itscoast lies in an area where sea level isrising relative to the land. Sea level riserespectively reaches +1.7 mm/year inStour Estuary, +1.4 mm/year in Crouchestuary, and +1.5 mm/year in Swale (Kent).A well known effect of sea level rise is thedepletion of salt marshes, which provide ahigh level of safety by absorbing waveenergy during storms. Some estimatessuggest that without a fringing saltmarsha sea wall needs to be four times as highand could cost ten times more toconstruct than one fronted by an 80mwide saltmarsh.
Loss of saltmarsh in the Essex estuaries in ha, derived from Burd (1992) and Coastal
Geomorphological Partnership (2000)
Original area Total area Total area Net loss Net loss
1973 1988 1998 1973-1998 1973-1998
Stour 264.2 148.2 107.4 156.8 59.3%
Hamford Water 876.1 765.4 621.1 255.0 29.1%
Colne 791.5 744.4 694.9 96.6 12.2%
Blackwater 880.2 738.5 683.6 196.6 22.3%
Dengie 473.8 436.5 409.7 64.1 13.5%
Crouch 467.1 347.4 307.8 159.3 34.1%
Thames (Essex) ? 197.0 181.0 No 1973 data
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Acceleration of the pace at which sealevel is rising, as observed today, couldtherefore jeopardize the ability of saltmarshes to provide cost-effectiveprotection to the hinterland against therisk of flooding.
Current shoreline management
strategies
The Essex coast provides a goodexample of the way in which thepolicies associated with coastaldefence, particularly those relating toprotection of the land from erosion andflooding, have developed over the last20 years or so in the United Kingdom.Since then the loss of habitat, changingperceptions of the implications of sealevel rise and cost of maintaining harddefences have all contributed to themove away from ‘protect at all costs’to a policy of ‘realignment’ whichaccepts that some land will be lost tothe sea. This combined with the use of‘softer’ engineering options, such asbeach recharge, represent a much moreflexible approach to coastal protection.However, it does not imply that thepolicy supersedes all locations wherecoastal protection may be in place.Indeed there are several large towns andvillages where protection is desirableand cost effective because of theassets they protect. The identificationof the most sustainable approaches tomanage risk along the shoreline overthe next 50 years has been supportedby the elaboration of the ShorelineManagement Plans (SMP) at the level ofeach coastal sediment cell,recommended by the Department forEnvironment, Food, and Rural Affairs(DEFRA) and the Environment Agency.The SMP for the Essex Estuaries wasenforced in 1995.
Future perspectives
It is clear from the analysis of thesituation in Essex that a rising sea levelimposes severe restrictions on thecapacity of the ‘Hold the line’ option tobe sustainable in the medium to longterm. Recent flooding events in the UK- and in the rest of Europe - suggestthat whatever is spent on capital and
maintenance of coastal protectionfeatures, extreme events will alwaysovercome the defences.
It is too early to tell whether the longterm realignment of the coast willachieve the aim of securing a moresustainable and cost effective approachto coastal defence. It is already clear,however, that the re-creation of mudflatsand salt marshes are possible and thatconsiderable benefits are derived fornature conservation. The case for andthe benefits derived from adopting amore flexible approach to coastalmanagement are becoming muchmore widely accepted as the policy ispromoted within the wider coastalcommunity and to the public.
In that perspective, the Essex EstuariesInitiative (EEI) - partly funded throughInterreg IIC - is a strategic approach tocoastal management, which aims tocoordinate and support the EssexEstuaries European Marine Site. This isa statutory designation which involvesa wide range of authorities from localauthorities to fisheries regulators, fromnature conservation agencies toharbour authorities. The main purposeis to ensure the nature resources of thecoast, both on sea and land, in order tocontinue supporting business, wildlife,and the sustainable development ofcoastal populations and nature areas.
The development of appropriatemanagement will facilitate theattainment of the twin goals of conser-vation of the European Habitat Directivewhilst at the same time maintainingand enhancing the socio-economicdevelopment of the area.
A.M.StaceyCudmore Grove Country Park. Salt marshes between thedefensive bank, the sea wall, and the beach.
Box: Shoreline management policy options in Essex
Policy 1: Hold the line by maintaining or changing the standard of protection. This policy should coverthose situations where works or operations are undertaken in front of the existing defences, to improve ormaintain the standard of protection provided by the existing defence line.This policy has been adopted atSales Point, Marsh House, Deal Hall and Hamford Water.
Policy 2: Move seaward by constructing new defences seaward of the original defences.
Policy 3: Managed realignment by identifying a new line of defence and constructing new defenceslandward of the original defences. Some experimental sites of this option were Blackwater Estuary,Orplands, Tollesbury and Abbost Hall.
Policy 4: Limited intervention by working with natural processes to reduce risks while allowing naturalcoastal change. This policy was adopted at Cudmore Grove.
Policy 5: Do nothing where there is no investment in coastal defence assets or operations.
management practices along the bayof Giardini are not sustainable. TheRegional Department of theEnvironment (ARPA) published apublic announcement relating to anmajor investment programme for theperiod 2000-2006. This publicannouncement contains theguidelines for the definition ofpriority areas to be protected and thetypes and schedule of measures to betaken. Literally, the aim of thisinvestment programme is the“removal of the causes ofdeterioration and/or erosion in thecoastal areas, by means of the
restoration of the natural conditionswhich led originally to the formationof the shoreline, with particularreference also to building activitiesinland, to the recovery and restitutionto their natural state of the wet anddry river courses and the restorationof the solid littoral transport.Particular attention is to be paid alsoto the effects on an increase in touristpotential, the recovery of stateproperty and the protection of privateand public goods from sea storms”.This investment programme is still inits definition phase.
A typical Mediterranean resort
The bay of Giardini Naxos is situatedin the Northern sector of the Ioniancoast of Sicily, between the towns ofMessina and Catania. The town ofGiardini Naxos has about 10,000inhabitants and is characterized bystrong tourism with more than 1million tourists per year. With its 34hotels and 46 restaurantsconcentrated along only 5 km ofcoastline, the bay of Giardini is quiteillustrative of coastal tourismdevelopment along theMediterranean sea. In summer, thepromenade may be frequented bymore than 20,000 tourists a day, i.e.twice the population of GiardiniNaxos.
The causes of erosion
Over recent years, several stretchesof the coast of Giardini have beensubject to intense erosive forces. This erosion is mainly driven by thedominant East and North East windsthat tend to generate southwardlittoral currents which mainly erodethe central –southern sector of thebay. However, it readily apparent thatthese erosive processes have been
aggravated by a series of man-madeconstructions within the catchment of Alcantara river, along the coast, or directly at sea (harbour quays). The coastal stretch between SanPancrazio’s church and lido Sirinetta isparticulalrly exposed and requirescontinuous protection since the1970s. This has been mainly achievedby the erection of rigid structures,such as groins and breakwaters.However, evidence has been giventhat these structures were rarelyplaced at a sufficient distance fromthe shore to be effective, inconsequence of that they had alimited efficiency causing furthererosion problems downdrift.
The reaction of regional authorities
Regional authorities have recentlygrown aware that the current erosion
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Tourism facilities in southern part of Giardini Bay
BAY OF GIARDINI NAXOS – SICILY
ESA – ENVISATExtract of a MERIS image . The green colour of the water along the southern coast of Sicily is due to longshore currents.Suspended matters taken away from the beaches are visible in the long plume extending along the southeast extremityof the island
What is at stake in Sicily ?
EUROSION estimates that about 900,000 inhabitants live within the radius of influence of coastalerosion is Sicily, which makes Sicily the fourth most exposed Italian region in terms of population atrisk, after Veneto (1,200,000 inhabitants), Tuscany (950,000) and Campania (915,000). However, Sicilycomes just after the Veneto region in terms of urbanised area at risk (250 km2 within the radius ofinfluence of coastal erosion) which is mainly explained by the presence of densely populated coastalsettlements along the coasts such as the cities of Palermo, Messina, Catania, Syracuse, or Taormina.Moreover, the coastal urbanisation growth rate in Sicily (about 30%) between 1975-1990 is among thehighest rates in Europe. EUROSION also estimates that Sicilian coasts also shelter about 315 km2 ofareas of high ecological value which are at risk of coastal erosion.
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When the amount of sediments movingalong the coast is high enough,outgoing sediments are immediatelyreplaced by incoming sediments andthe shore is overall stable. Duringstorm surges the amount of sedimentsremoved is much higher but generallyrestored during the calm seasons.
However, in the case of Aveiro, harbouractivities have significantly modifiedsediment transport patterns by trappingsediments at the level of itsbreakwaters and by regularly dredginglarge amount of materials from theentrance channel. Yet, harbouractivities cannot be considered as theonly reason for erosion south of Aveiro(four to six meters per year alongIlhavo shoreline): the heavily dammedIberian rivers as well as an average one mm sea level rise per year alongthe Portuguese coast are also suspectedto contribute to coastal erosion patterns.
Coastal erosion has already causedsevere economical losses by reducingthe frequentation of beaches, estimatedto half a million people during summerin Aveiro. In the same time, the cost forcreating and maintaining efficient coastalprotection works – which in 1998 reached2,2 million euros for the seafront ofIlhavo and Vagos only - has resulted inlower value for land propertiesestablished along the coast (down to80% of initial value in some places).
On a longer term perspective, thecoastline is expected to retreat to sucha point that new inlets will break withconsiderable damage to the lagoon.Predictable damages include both theflooding of low-lying built areas and theintrusion of salt water into agriculturallands.
How to address coastal erosion:
the ICZM approach
Lessons learnt from the past havedemonstrated that hard engineeringprotection structures – such as groins,seawall, and breakwaters - establishedby the national and local authoritiesalong the coast, provide very localsolutions which do not address theunderlying cause of erosion (shortageof sediment) and generally acceleratesthe problem down-drift of the coastalprotection.
To address this issue, whoseconsequences may affect the wholelagoon ecosystem and relatedactivities (fisheries, aquaculture,tourism), the national and regionalgovernments, municipalities, theharbour authority, and variousuniversities have joined their efforts tofind integrated solutions (see boxbeside).
AVEIRO
An open door towards the Iberian
peninsula
Aveiro has an unrivalled position, ingeostrategic terms, at the intersectionof two vital transport axes:longitudinally, the axis linking Galiciato South of Portugal, and transversallythe axis linking the Atlantic Ocean toCentral Spain. Together with CostaNova - Vagueira, Ilhavo and Vagos, itsneighbouring municipalities, Aveirohosts nowadays 132,000 inhabitants(2001 census), 10% more than in 1991.
The geostrategic position of Aveiro iscombined with an outstandingecological context, the municipalitybeing located right at the tidal inlet of thelagoon “Ria de Aveiro”. “Ria de Aveiro”ecosystem shelters a wide range ofnatural habitats including sandy coastand dune systems with a highrecreational value, as well as salt andbrackish marshes suitable for fisheriesand aquaculture, which together withharbour activities constitute the majorsources of income for Aveiro citizens.
Aveiro harbour is of significantimportance nationally, with a fastgrowing annual freight traffic, whichamounted to 2,820,000 tons in 2001.Aveiro harbour benefited during the lastfive years from significant investments,including those from the EuropeanRegional Development Fund (ERDF), tobecome a major intermodal hub and afirst class short-sea shipping port inSouthern Europe in line with theEuropean Transport Policy.
The Ria de Aveiro
In the front of the bay, formed by thedeposit of sediments from the flow ofthe rivers Vouga, Agueda and Certima,Ria de Aveiro is one of the finest
ecosystems and one of the mostextensive wetlands in Portugal. Part ofthe Ria – the natural reserve of SanJacinto dunes – already enjoys a legalprotection status. Other parts of the Riamay be designated in the near futureas part of the Natura 2000 network.
More than fifty fish species live in theRia of Aveiro, some of which rely onthe estuarine system for spawning andgrowing. Mullet, bass, gilt sea bream,white sea bream, sole and eels are thebest known fish that can be found inthe Ria. Cockle, carpet shell, clam andrazor shell are among the most exploitedbivalve molluscs in the Ria. They aremanually collected on mudlflats at lowtides or “ dredged” in the channels.Finally, the Ria hosts various shorelinebird species, migrants or residents, suchas godwits, dunlins, plovers, stilts,avocets, herons and birds of preys.
The threats on the coast
More than the risk of industrial pollutioninduced by harbour activities, coastalerosion is estimated to be the mainimmediate threat affecting Aveirocoastline in terms of economy, peopleand nature at risk. Along sedimentarycoasts (beaches, dunes, flats), obliquebreaking waves generate turbulenceswhich remove and transport sedimentsin a longshore direction.
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Eng. Mota Lopes (DRAOT-CENTRO)The picture illustrates the extent of coastal erosion in Vagueira, located 9 km south of Aveiro habour entrance. Sediments carried along the coast by longshore currents arepartly trapped by Vagueira’s groin, which results in a sediment deficit downdrift and coastal erosion in the non protected section of the waterfront.
Eng. Mota Lopes (DRAOT-CENTRO) Aveiro resort located south of the Harbour.
SOLUTIONS PROPOSED
• Working with the harbour authority to implement a“sand by-passing” system from north of theharbour entrance breakwater to south, thusreactivating the sediment transport processes;
• Identifying areas where natural coastal protectionprocesses could be stimulated, such asrehabilitated dunes or beaches regularly supplied
with non-contaminated materials collected from
dredging activities along navigation channels;
• Severely controlling illegal sand extraction
activities and any other activity which may disturbnatural beach and dunes restoration;
• Regulating urban seafront extension, in order tomaintain protection costs at a low level.
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The results of the EUROSION casestudies and other Europe wideevidence, suggests that too often in thepast insufficient attention has been paidto the functioning of the wholesedimentary system (as depicted above).In this context sediment availability (orlack of it) is of fundamental importance.In order to link the two key elements of‘sediment availability’ and ‘functionalspace’ for sediment dynamics to operateEUROSION proposes the identificationof ‘strategic sediment reservoirs’.
Strategic Sediment Reservoirs
A negative sediment balance in aparticular coastal area is likely to leadto erosion and an increased threatfrom flooding. EUROSIONrecommends that to counteract thesetrends a source of sediment should beidentified, which would help improvethe ‘resilience’ of these areas. These‘Strategic Sediment Reservoirs’ couldbe derived from:
• offshore: sands on the sea bed(below low water);
• the coastal area: eroding cliffs;intertidal shingle, sand and mudbanks (supporting shingle structures,dunes and beaches) and lessvaluable agricultural land;
• the hinterland: this option is to beconsidered if insufficient sedimentreserves are available either offshoreor within the coastal area.
In some areas a positive sedimentbalance may hamper sustainabledevelopment locally e.g. in port orsea resort areas. In these cases it maybe appropriate to consider makingmaterial removed from the system(e.g. to keep harbour entrances open)available for the future by ‘feeding’an offshore sediment reservoir.
The identification, designation and useof strategic sediment reservoirs shouldbe subject to environmental impactassessment (cf. EUROSIONRecommendation nr. 2) and be costeffective (cf. EUROSIONRecommendation nr. 3). They must alsobe environmental acceptable and beable to contribute effectively to coastal‘resilience’.
These requirements are more likely tobe met if the sediments within thereservoir have characteristics thatclosely resemble those in the localarea. By definition, after designation,sediment reservoirs should be leftundeveloped.
Major concerns: what is at stake?
EUROSION has identified thefollowing trends, which are likely tohave an increasingly adverse affecton the coastline of Europe over thenext 50 years unless policies arechanged:
• Sediment loss through riverregulation and dam construction,dredging, sand mining and offshoresediment extraction;
• Loss of dynamic coastlines andnatural habitats as a result ofcoastal urbanisation, enclosure oftidal land, golf course development(on dunes), or by the use ofsedimentary habitats to providesources of sediments tocompensate for chronic losses dueto human interventions;
• Loss of resilience as the coastbecomes more vulnerable toerosion and flooding;
• An accelerated sea level rise andmore unpredictable and extremestorm events as a result of climatechange.
All of these hazards and risksassociated with them areunpredictable. However, what is clearis that the increase in coastal erosionand flooding will result in anincreasing cost to society, namelythrough:
• Risk to lives and economic assets.Protecting some of our importanttowns and cities is likely to becomea major drain on resources leavinglittle spare capacity for the protectionof other less valuable assets;
• Increasing habitat loss. It can beexpected that considerable areas ofcoastal dunes and wetlands willdisappear and with it their social,economic and ecological functions;
• Greater mitigation andmanagement cost. The current trendin coastal defence, which may resultin excess of 10,000 kilometres being‘protected’ by 2020 will becomeincreasingly economicallyunsustainable.
The European dimension
The major problem posed by coastalerosion and flooding has only recently
THE EUROSION VISION
Understanding the dynamic nature ofthe coastal margin is a key factor inmanaging coastal erosion. Humanpopulations have always tended tofavour settlement along the coastalmargin. In historical times these werelargely at the mercy of the forces ofnature. From Roman Times onwardscoastal defences have been built toprotect ‘new land’ created duringperiods of relative sea level fall orwhen an increased sediment supplyresulted in shoreline accretion.Structures such as sea walls and groinfields have not only helped to sustainthese lands from erosion and flooding,but also provided the impetus for morecoastal land to be developed. This hasin turn resulted in a sometimesdramatic loss of habitats (especiallycoastal dunes, beaches, intertidalsaltmarshes, sand and mud flats, andseagrass beds) and with them areduction in their natural dynamiccharacteristics.
EUROSION has shown that whilstprotection is possible, extreme eventsundermine and/or overtop coastaldefences locally. Long term trends andknock-on effects from the structuresthemselves can also result in negativeeffects on the resilience of much largercoastal units. It is anticipated that thissituation will be aggravated by risingsea levels and a more unpredictableand extreme storm climate associatedwith climate change. This will result ina long term threat to the safety ofpeople, the sustainability of manycoastal activities, coastal biodiversity(including Natura 2000 sites) and theability of the coast to provide a‘natural’ coastal defence. In extremesituations the coastal margin candisappear altogether (see figureopposite). In this context themaintenance of artificial shorelinesneeds to be re-examined.
Coastal resilience
EUROSION recognises the sustainabledevelopment of coastal zones and theconservation of dynamic habitats,especially on the remainingundeveloped coast, as important longterm goals for European coastal zones.This requires a respect for, and inmany cases restoration of, the naturalfunctioning of the coastal system andhence its natural resilience to erosionand flooding.
The implications of coastal resiliencevary depending on the coastal type.For hard rock coasts resilience may notbe critical because the rocksthemselves are resistant to erosion.Conversely active erosion of ‘soft-rock’
cliffs (bluffs) is often a naturalphenomenon contributing material tothe coastal sediment volume. In itsturn this can increase shoreline width,protecting the cliffs themselves fromwave attack and helping to support thedevelopment of sedimentary habitatson adjacent shorelines. Where thisinterplay is maintained and thesediment budget is positive or inbalance then the resilience of the widersystem is more likely to remain intact.
Two key factors can be identified indetermining whether sensitive(‘soft/dynamic’) coastal systems areinherently resilient or not:
1. local availability of sediments insufficient quantity to sustain thedynamic equilibrium betweenerosion and accretion and attaininga ‘favourable sediment status’.Chronic losses of sediments willlead to an increase in the balance oferosion over accretion andultimately in a loss of habitat andnarrowing of the shoreline;
2. space for coastal processes to
operate. Limitations on the spaceavailable to accommodate thenatural retreat of cliffs andsedimentary habitats and/or theredistribution of sediments as aresult of this retreat will decreasecoastal resilience.
Some of the factors important to thedelivery of sediment to the coastalzone are shown in the figure below.
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EUROSION defines coastal resilience as the inherentability of the coast to accommodate changes inducedby sea level rise, extreme events and occasionalhuman impacts, whilst maintaining the functionsfulfilled by the coastal system in the longer term. The concept of resilience is particularly important inthe light of the predictions for global climate change.
‘Strategic Sediment Reservoirs’ can be defined as:amounts of sediment of ‘appropriate’ characteristicsthat are kept available for future replenishment of thecoastal zone, either temporarily (to compensate forlosses due to extreme storms) or in the long term (at least 100 years).
Some of the principle causes of change in sediment movement in a ‘sediment system’. In this diagram the coast is taken to include the sea cliffsand sand dunes, tidal saltmarshes and mud/sand flats. Nearshore marinewaters (blue) and the hinterland (green) make up the ‘sediment system’. In the diagram sediment movement is tending towards ‘sediment sinks’associated with a coastal embayment, such as an estuary
Armed with this information it will bepossible to develop appropriatepolicies to manage the erosion andflood risk within the sediment cell. This management should be based ona number of policy options 1, which insummary are:• Hold the line;• Move seaward;• Managed realignment;• No active intervention.
been recognised as a key issue atcommunity level. The EuropeanCommission Strategy for IntegratedCoastal Zone Management (2000) firstidentified the importance of the issuewith Members of European Parliamenttaking it forward by allocating thebudget for the EUROSION study. The variety of socio-economic andenvironmental risks associated withthe current trends in coastal erosionand the threat from flooding has ledEUROSION to attach considerableimportance to the concept of ‘coastalresilience’. ‘Strategic sedimentreservoirs’ by helping to attain afavourable sedimentary budget withina specific coastal area would helpcreate the conditions for improving‘resilience’ and reducing the threatsfrom erosion and flooding.
This could be achieved either byamending existing directives – notablythe Water Framework Directive and theHabitats Directive – or by consideringthe opportunity to develop a specificdirective on sediment management. Inaddition to the Europe-wideenvironmental and socio-economicimplications of current erosion trendsthere are at least two other reasons forsuggesting Community levelinvolvement:
1. Catchments and the movement ofwater and sediments within themoften transcend nationalboundaries. For example riverregulation works may have impactson coastal zones of other MemberStates;
2. Current coastal erosionmanagement tend to see Natura2000 sites as sources of sedimentor as areas that can be ‘sacrificed’in areas of erosion. This has longterm and possibly irreversibleimplications for the Natura 2000Network.
EUROSION judges that a legal
response – through amending existingdirectives or proposing a new directive– aimed at clarifying the internationalstatus of sediments must beconsidered seriously in order to laydown the conditions for coordinatedsediment management at the EU level.In this respect, the approach is similarto that advocated within the WaterFramework Directive. Beside this legalresponse, EUROSION also proposes anumber of accompanying measureswhich can be best achieved throughnon legal arrangements.
Local action - Coastal Sediment
Management Plans (CSMP)
Whatever legislation is adopted atEuropean or national level,
management takes place at thelocal/regional level. EUROSION laysgreat emphasis on applying theconcepts identified above to localdecision making. In this context itrecommends coastal erosionmanagement should move away frompiecemeal solutions to a plannedapproach. This should be based uponaccountability principles, which optimiseinvestment costs against values at risk,increase social acceptability ofproposed actions and keep optionsopen for the future. This move shouldbe driven by the need to restore the‘coastal resilience’ and meet theconditions for ‘favourable sedimentstatus’.
A Coastal Sediment Management Planprovides the building block for coastalerosion management. In line with thevision developed by EUROSION, aCoastal Sediment Management Plan(CSMP) is a document, which “sets theobjectives of favourable sedimentstatus within a specific coastalsediment cell and defines the meansfor achieving these objectives”. Figure 3indicates the principle components of acoastal sediment cell in relation to thecatchment and near shore zone.
A first stage in any CSMP must includeidentification of all the principle forcesinfluencing the rate at which sedimentis removed from (or delivered to) thesystem and the way in which thedynamics operate. These should beassessed:- on a timescale of at least 30 years,
increasing to 50 or 100 years in somecases;
- with an understanding of the wholesedimentary system from thecatchment to the coast and includingthe near shore marine environment(see figure 3 above);
- and takes account of economic,social and environmental effects.
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The coastal sediment cell is made up of the principle coastal habitats (plusshingle shores and structures) as shown in the diagram.
Arradon (France) - courtesy: Philippe Hermange
1 Based on the UK approach to Shoreline Management Plans, Interim Procedural Guidance, DEFRA 2003 available @http://www.defra.gov.uk/environ/fcd/
On the basis of the findings and theEUROSION Vision four keyrecommendations are proposed that,once implemented as a package, willmake coastal erosion problems andrisks in Europe manageable.
Based on the findings, EUROSIONproposes the introduction of the conceptof favourable sediment status within theEuropean legislation as the cornerstoneof coastal resilience and sustainableshoreline management. Because sedimentmanagement involves different sectors– including soil, water and habitatmanagement – several options aresuggested to facilitate the introduction ofthis concept within European legislation.The objective of favourable sedimentstatus for the coastal zone shall beachieved for each coastal sediment cellprincipally via the designation of strategicsediment reservoirs in combination withtraditional measures such as spatialplanning, building regulations,environmental assessment procedures,and coastal erosion mitigation measures.
From a coastal resilience point of view,the status of coastal sediments isfavourable when:a) their actual volume and distribution
approximates to the situation beforechronic loss of sediments started tooccur as a result of humanintervention, with regard to:• net input of sediment from river
catchments;• longshore sediment drift;• cross-shore sediment exchange.
b) the resistance of sediments toerosive forces is supported by theirnatural geological texture,vegetation or by a natural flexibilitymitigating loss of natural resistance.
By introducing the concept of favourablesediment status into the Europeanlegislation, it is expected that futuremanagement policies will take intoconsideration the undisturbed conditionsof the sediment system and will makeprogressive efforts towards restorationof these conditions a legally bindingobligation at the European level.
The identification and designation of‘strategic sediment reservoirs’ for eachcoastal sediment cell is seen as amechanism that will facilitate therestoration of a favourable sedimentstatus and the provision of space forcoastal processes to take place. It is important to understand thedifferent processes, which maygenerate a demand for sediments. It istherefore valuable to make adistinction between different types ofsediment reservoirs. In the process ofdesignating strategic sedimentreservoirs, EUROSION recommendsidentifying three types of sedimentreservoirs: • type 1: buffer zones between land
and sea• type 2: sediment stocks to adjust to
sea level rise• type 3: sediment stocks to
compensate for a human-inducedsediment deficit.
EUROSION proposes to adopt theconcept of a Coastal SedimentManagement Plan (CSMP) as follows:
Actions to be taken at EU-level
EUROSION proposes that the conceptsof a ‘favourable sediment status’ ofcoastal zones and of ‘strategicsediment reservoirs’ be introducedwithin EU legislation. This can be doneeither by amending existing directives– notably the Water FrameworkDirective and the Habitats Directive –or by considering the opportunity todevelop a specific directive onsediment management. The rationalefor introducing these concepts at thelevel of a directive is that sedimentmanagement is a cross-border sectorwhich interacts, and in certain casesconflicts, with the requirements ofother existing European directives andpolicies. These mechanisms should beimplemented through the preparationof Coastal Sediment ManagementPlans for vulnerable coastal zones.
Actions to be taken at Member
States level
Member States are encouraged toprepare a national policy framework tocoastal resilience and promote theelaboration of Coastal SedimentManagement Plans. In particular, the responsibility ofMember States for the maintenance ofthe Natura 2000 Network requires thatthe implications of favourablesediment status and strategic sedimentreservoirs on designated habitats andassociated species are taken fully intoaccount. Member States should ensurethat areas designated for natureconservation (Natura 2000) are notused as sources to supply sediments tocompensate chronic deficits ofsediments as a result of humanintervention.
Current EIA procedures have notsufficiently addressed human-inducedcoastal erosion. This can be improvedthrough better incorporating coastalerosion concerns (especially riskassessments) into the implementationof existing instruments at all levels ofadministrations. EUROSION proposesthe following:
Environmental Assessment
EUROSION has prepared Guidelinesfor incorporating coastal erosion issuesinto Environmental Assessment for EIApractitioners. The European Directive2001/42/EC on Strategic EnvironmentalAssessment (SEA) recognises theimportance of taking a wide-rangeperspective when addressing thecumulative impact of piecemealdevelopments and could be used toaddress coastal erosion and floodingissues. This is particularly relevant tomanagement within water catchmentareas and coastal and near shorecoastal zones.
Hazard and risk mapping
In most countries coastal erosion risksare not sufficiently assessed, so it isproposed to bring the various existingapproaches together into a commonmethodology. To this end EUROSIONhas prepared Guidelines for mappingcoastal erosion hazards.
Spatial planning
By incorporating coastal erosionhazards and risk mapping into long-term plans local and regionalauthorities can effectively divertdevelopment from areas at risk fromerosion, and reduce financial claims tocompensate erosion damage.
FOUR RECOMMENDATIONS TO IMPROVECOASTAL EROSION MANAGEMENT
EUROSION Recommendation nr. 1
Restoring the sediment balance and providing space for
coastal processes
A more strategic and proactive approach to coastal erosion
is needed for the sustainable development of vulnerable
coastal zones and the conservation of coastal biodiversity.
In light of climate change it is recommended that coastal
resilience is enhanced by: (a) restoring the sediment
balance; (b) allocating space necessary to accommodate
natural erosion and coastal sediment processes and (c)
the designation of strategic sediment reservoirs.
Favourable sediment status
The favourable sediment status for coastal systems maybe defined as the situation where the availability of‘coastal sediments’ supports the objective of promotingcoastal resilience in general and of preserving dynamiccoastlines in particular. Coastal sediments consist ofonshore and near shore sediments derived from coastalcliffs, marine deposits and riverine sources.
RijkswaterstaatProtection of coastal dunes in the Netherlands
Coastal sediment cell:
EUROSION defines a coastal sediment cell as acoastal compartment that contains a complete cycleof sedimentation including sources, transport paths,and sinks. The cell boundaries delineate thegeographical area within which the budget ofsediment is determined, providing the framework forthe quantitative analysis of coastal erosion andaccretion. In this respect, coastal sediment cellsconstitute the most appropriate units for achievingthe objective of favourable sediment status andhence coastal resilience. In practical and management terms, the coastalsediment cell sits within a sedimentary frameworkcomposed of three geographical zones: the catchment,the shoreline, and the near shore marine environment.
Coastal Sediment Management Plan (CSMP):
a high level document that sets the objectives offavourable sediment status within a specific coastalsediment cell and defines the means for achieving these objectives. This concept is further developed underRecommendation nr. 3.
EUROSION Recommendation nr. 2
Internalise coastal erosion cost and risk in planning and
investment decisions
The impact, cost and risk of human induced coastal
erosion should be controlled through better
internalisation of coastal erosion concerns in planning
and investment decisions. Public responsibility for
coastal erosion risk should be limited and an appropriate
part of the risk should be transferred to direct
beneficiaries and investors. Environmental Assessment
instruments should be applied to achieve this. Risks
should be monitored and mapped, evaluated and
incorporated into planning and investment policies.
Archief Natuurcentrum AmelandAcute erosion during a storm surge in Ameland (Wadden Sea)
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Financial instruments
The design of innovative fundingmechanisms is proposed, in particular:• measures to support the
implementation of Coastal SedimentManagement Plans;
• financial compensation schemes toaccommodate the resettlement ofcoastal populations at imminent riskfrom coastal erosion or flooding;
• a broader use of financial marketinstruments, in particular to transferthe costs related to adverseconsequences of coastal erosion (theexternalities) from the community tothe investors through insurancepolicies, bank loan conditions, andlimitations to disaster compensationfunds.
Integrated Coastal Zone Management
In combination with EnvironmentalAssessment instruments the EURecommendation on ICZM (2002) canbe used to identify mitigation solutionswhich are innovative, cost-effective,and socially acceptable. WhereverICZM plans are implemented, CoastalSediment Management Plans shall beconsidered as part of them.
Actions to be taken at EU-level
As part of a wider initiative on risksand insurance it is recommended thatthe European Commission launches adebate on instruments that couldtransfer an appropriate part of the costof combating coastal erosion in riskareas to the beneficiaries and investors.
As part of an assessment of all financialinstruments and in the implementationof the Nature and the EnvironmentalAssessment directives, it is important toassess the potential impacts of projectson the coastal sediment balance and risksto the safety of people, economic assetsor coastal biodiversity. Appropriatemitigation and compensation measuresshould be considered in this assessment.Projects in the field of infrastructure(Trans-European Networks, short seashipping) and water managementshould not be supported if they arelikely to cause adverse impacts requiringsubsequent mitigation measures.Funding incentives should be consideredfor the elaboration of risk maps.
Actions to be taken at Member
States level
Coastal erosion should become amandatory topic to be assessed inrelation to a wide variety of plans andprogrammes affecting the coast(including planning, transport, touristdevelopments and offshore aggregateextraction). SEA should be promotedas an important new instrument forEnvironmental Assessment for coastalerosion management.
The management of expectations inconnection with risk is a crucial part ofpolicy application. It must be madeclear that development in risk locationswill only be allowed where it does notlead to the need for subsequent actionto reduce the level of risk from coastalerosion.
In connection with the identification ofstrategic sediment reservoirs it isimportant to prepare a mechanism toallow for expropriation or compensationin order to accommodate managedrealignment in compliance with ECcompetition regulations. An example isprovided by the French Law thatfacilitates expropriation of assetsthreatened by natural hazards (LoiBarnier).
Actions to be taken at the local level
Authorities should promote publicinformation and awareness of coastalerosion risks as a basis for coastalplanning and management, e.g.through the dissemination of risk mapsat local scale (1:25,000). Consultationwith stakeholder groups and thepublic, to help ensure that coastalmanagement policies are understoodshould be a priority. Particular attentionshould be given to EnvironmentalAssessment in relation to socio-economic and financial risks.
An accountable coastal erosion
management
• has explicit objectives for a definedtimescale;
• defines clear responsibilities at thevarious levels of administration;
• is based upon an understanding ofthe sediment balance and long termtrends;
• does not compromise safety,important environmental values andnatural resources;
• is based on a cost-benefitassessment;
• is supported by an appropriatebudget for both investments andmaintenance as well as for afinancial mechanism to locallyaccommodate erosion or its impacts;
• is implemented by technicalmeasures that have proved to be fitfor purpose;
• includes a programme to monitordevelopments and effectiveness ofmeasures;
• determines the duty to publiclyreport on all above aspects.
Scope of CSMPs
Coastal sediment management plansprovide one element in thedevelopment of integratedmanagement of coastal areas. Besideachieving coastal resilience, a keycomponent of a CSMP is that it shouldprovide a large-scale assessment ofthe risks associated with the operationof coastal processes and present thesein the context of a long term policyframework. The key principle is thatthey should help to reduce risks in asustainable manner. A CSMP should bea high level document that forms animportant element in any overallstrategy for flood and coastal defence.
A first stage in any CSMP must includeidentification of all the principle forcesinfluencing the rate at which sedimentis removed from (or delivered to) thesystem and the way in which thedynamics operate. This will need to beassessed:- on a timescale of at least 30 years,
increasing to 50 or 100 years in somecases;
- with an understanding of the wholesedimentary system from thecatchment to the coast and includingthe nearshore marine environment(see figure 6 above);
- taking account of economic, socialand environmental effects.
Although the consequences of erosionmay be the loss of property and land,the greater impact is caused when low-lying areas (particularly at the coastalmargin) flood. It is therefore importantto recognize the value of coastalsedimentary habitats (notably tidalflats, saltmashes and sand dunes) inproviding natural defences. At thesame time the opportunities forrestoring nature conservation,recreational and landscape features inrealignment or non interventionschemes should not be overlooked.
The CSMP should define the objectivesfor each coastal segment or cell interms of target thresholds for meetingthe conditions of a ‘favourablesediment status’. These objectives maybe best described using a combinationof four generic policy options (adaptedfrom the generic policy optionsidentified in the UK):• Hold the line• Move seaward• Managed realignment • No active intervention
Actions to be taken at EU-level
As part of the existing conditionalityassessments of all financialinstruments and banks, coastal erosionmanagement projects should not besupported if they could cause adverseimpacts requiring subsequentmitigation measures. Instead, fundingincentives should be provided toprogrammes aimed at restoring thesediment balance and coastal resilience.
Actions to be taken by Member States
Responsibilities for elaborating coastalsediment management plans shouldbe passed on to regional authoritieswhose coastline is entirely or partlyincluded within a coastal sediment cell.When more than one region isconcerned, interregional arrangementsshould be established to elaborateshoreline management plans.
Member States should promote thedissemination of best practiceinformation on coastal erosionmanagement in their own language.
EUROSION Recommendation nr. 3
Make responses to coastal erosion accountable
Coastal erosion management should move away from
piecemeal solutions to a planned approach based upon
accountability principles, by optimising investment costs
against values at risk, increasing social acceptability of
actions, and keeping options open for the future.
This move should be driven by the need to restore the
coastal resilience and the favourable sediment status
and be supported by Coastal Sediment Management
Plans (CSMPs).
Piotr DomaradzkiSlope profiling in Rewal. The main erosion problem inthis place is wrong ground water management. Anincreased erosion in the neighbourhood is visible.
Albert SalmanWindbreak fences (called Ganivelles) are used inCamargue to restore the dunes
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(on a series of topics) and to thedesign and implementation of nationaland regional platforms for sharing keydatasets.
Actions to be taken at EU-level
In the framework of the establishmentof an Infrastructure for Spatial Data inEurope (INSPIRE) the standardizeddelineation of coastal sediment cellsshould be supported by incorporatingkey input datasets required for such adelineation into Spatial DataInfrastructure (SDI) standards.
Future community research activities of the Global Monitoring ofEnvironment and Security (GMES)towards the establishment of Europe-wide standardizedmethodologies for delineating coastalsediment cells, includingmethodologies relating to theproduction or modelling of datasetsrequired for delineating such sedimentcells, and towards shorelineeconomics.
Priority should be given to thedevelopment of valuation techniqueswhich enable a cartographicrepresentation and GIS processing ofsocial, ecological and economicalvalues of coastal zones. Such arepresentation should facilitate thetransition from coastal erosion hazardmaps to coastal erosion risk maps, andsupport the implementation of cost-benefit assessment studies.
Actions to be taken by Member States
Member States should support thestandardized delineation of coastalsediment cells through the productionof key input datasets and theirintegration into their national spatialdata infrastructure (NSDI). MemberStates should also liaise with the GMESinitiative to jointly develop astandardized methodology for mappingthe boundaries of coastal sedimentcells, especially on cross-border cells;and they should support interregionalcooperation as well as research anddevelopment to support the jointelaboration of CSMPs.
Actions to be taken at the local level
At regional to local scales, production,processing, storage, update, exchange,and dissemination of relevantinformation on coastal erosionprocesses and coastline managementshould be considered as keyprerequisites to ensure successfulshoreline management operations.Regional authorities should play a leadrole in creating the adequate institutionaland technical conditions for suchactivities to take place, and for theirbenefits to be maximised. This should beachieved through the elaboration andimplementation by regional authoritiesof a strategy on “coastal information
governance”.This strategy should notbe restricted to coastline management,but extended to the broader context ofintegrated coastal zone management,wherever such approaches exist.
Actions to be taken at the local level
Regional authorities should takeresponsibility for the development ofCSMPs and ensure that shorelinemanagement is made fully compliantwith the above principles ofaccountability. CSMPs should beestablished for five to ten years, besubject to a SEA, and periodicallyevaluated and revised.
Exposure of European coastal regions
to coastal erosion
EUROSION recommends a rating ofEuropean coastal regions accordingto their exposure to coastal erosion.The rating is based upon factorsindicating pressures, state andimpacts of coastal erosion. The ratingshould set the timeframe forestablishing and re-evaluatingsediment management plans at thelevel of regional authorities andcoastal sediment cells and shouldserve as a basis for establishingpriorities for implementing theEUROSION recommendations, and
should be revised every ten years. The results of a first assessment onthe basis of the EUROSION databaseare presented in the central page ofthis brochure.
Delineation of coastal sediment cells
The delineation of coastal sedimentcells is an important but complextask. Efforts should be undertaken toharmonise this work on the basis ofdatasets on the coastline,hydrography, coastal elevation andbathymetry, nearshore wave regime,and astronomical tides. Specificattention shall be given to theidentification of sediment sources,sinks and circulation patterns.
Research on climate change impacts
on the shoreline
It is extremely important to continueand increase the research on theimpacts of climate change, not onlyon coastal ecosystems but also onwetland evolution (especially tidalsand, mud flats and salt-marshes, andthe effects of associated mitigationand stabilization measures) on returnperiods of extreme wave heights andon the extent of salt water intrusion.
Interregional cooperation on coastal
sediment management planning
European countries and regions andthe Commission should broaden theirinterregional cooperation to supportthe joint elaboration of coastalsediment cell-based CSMPs. Prioritiesshall be given to the developmentand dissemination of best practices
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EUROSION Recommendation nr. 4
Strengthen the knowledge base of coastal erosion
management and planning
The knowledge base of coastal erosion management and
planning should be strengthened through the development
of information management strategies.These should
include dissemination of ‘best practice’ (what works and
what doesn’t), provide a proactive approach to data and
information management and promote institutional
leadership at the regional level.
RijkswaterstaatThe Water En Strand Profiler (WESP) is a multi-purpose vehicle constructed to aid in the monitoring of the Dutch coastal area. It can operate fromthe beach and drive into the sea up to water depths of 8 meters
Natural and digital views of the Neddles (Isle of Wight). The digital view has been obtained via airborne laser altimetry(Lidar), which offers tremendous opportunities for coastline monitoring
EUROSION PRODUCTS
Beside its findings and policyrecommendations, EUROSION hasdeveloped since early 2002 a widerange of products – including reportsand a database – which are accessiblethrough the EUROSION web site(http://www.eurosion.org) or uponrequest to the European Commission.Major among these products are:
• The EUROSION database. This GISdatabase has been developed atscale 1:100,000 and can be viewedwith any standard GIS softwarepackage. It contains 19 layers ofinformation including administrativeand maritime boundaries, coastalelevation and bathymetry, coastline,geology, geomorphology, coastalinfrastructure, coastal defence works,erosion trends, land cover, landcover changes since 1975, wave andwind regime, sea level rise, tidalrange, river sediment transport,areas of high ecological value,budget invested in coastal defence,and regional exposure to coastalerosion risk. Most of these layers arecopyright-free and can be simplyobtained from EUROSTAT. Others arecopyrighted and require theauthorisation of data providers.Readers interested to know moreabout the database, or interactivelyvisualize some extracts of thedifferent layers, are invited to visitthe EUROSION map-server athttp://www.eurosion.org
• Guidelines for incorporating coastalerosion issues into EnvironmentalAssessment (EA) procedures. Thisguidance document provides someinformation on how to successfullyintegrate coastal erosion processesin the design of projects and duringthe early stages of theirdevelopment. The document alsoreviews a number of mitigationsolutions which can be adopted byproject developers. These guidelineshave been designed for EIApractitioners, including both projectdevelopers and public authoritiesresponsible for the developmentconsent.
• Guidelines for mapping coastalerosion hazards. This documentreviews the main methods used inEurope to map the evolution ofshoreline at “low cost”. In turn, thesemethods can help incorporate
coastal erosion concerns into spatialplanning processes at the level ofregional and local authorities.
• Guidelines for assessing costs andbenefits of coastline managementtechniques. This documentintroduces to the assessment ofcosts and benefits of coastal erosion mitigation measures. It pays aparticular attention to theassessment of external costs (orcosts of environmental damages)and the assessment ofenvironmental benefits.
• Guidelines for implementing localinformation systems dedicated tocoastline management. Thisguidance document presents the keyrequirements for a successful anddecision-oriented information systemin the fields of coastlinemanagement. These requirementscover a broad range of aspectsincluding institutional andorganisational procedures, functionalrequirements, data contentspecifications, database modelling,spatial representation, and dataaccess and exchange technologies.This document was mainly designedfor regional authorities willing toimplement such local informationsystems, and their subcontractors. Inaddition to the guidelines, a prototypeof a Local Information System hasbeen developed and can be customizedfor any regional authority willing tofacilitate coastal data sharing amongregional and local stakeholders. Thisprototype is also meant for regionswilling to get connected to oneanother and to have access to theEurope wide database. Installation ofthis prototype does not require anyparticular software license. A CD-ROM of the prototype can beobtained upon request.
• EUROSION Shoreline ManagementGuide. The Shoreline managementGuide is a review of about 60experiences of coastal erosionmanagement in Europe. This guide isnot meant to be a coastal defencemanual but rather a source ofknowledge where successes andfailures of coastal erosionmanagement throughout Europehave been documented. The guide is accessible from the EUROSION web site.
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European Commission
Living with Coastal Erosion in Europe – Sediment and Space for SustainabilityLuxembourg: Office for Official Publications of the European Communities2004 - 40 pp. - 21 x 29,7 cmISBN 92-894-7496-3
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-59-04-952-EN
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