Sustainable Coastal Policy Developments in The Netherlands. A Systematic Approach Revealed

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Sustainable Coastal Policy Developments in The Netherlands A SystematicApproach RevealedAuthor(s) M van Koningsveld and J P M MulderSource Journal of Coastal Research Number 202375-385 2004Published By Coastal Education and Research FoundationDOI httpdxdoiorg1021121551-5036(2004)020[0375SCPDIT]20CO2URL httpwwwbiooneorgdoifull1021121551-5036282004290205B03753ASCPDIT5D20CO3B2

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Journal of Coastal Research 20 2 375ndash385 West Palm Beach Florida Spring 2004

Sustainable Coastal Policy Developments in TheNetherlands A Systematic Approach RevealedM van KoningsvelddaggerDaggerlowast and J P M Mulderamp

daggerWLzDelft HydraulicsMarine and Coastal

ManagementPO Box 1772600 MH Delft

The Netherlandsmarkvankoningsveld

wldelftnl

DaggerUniversity of TwenteWater Engineering and

ManagementPO Box 2177500 AE Enschede The

Netherlands

ampRijkswaterstaatNational Institute for

Coastal and MarineManagement RIKZ

PO Box 209072500 EX Den Haag

The Netherlands

Netherlands Centre forCoastal Research NCK

PO Box 1772600 MH Delft

The Netherlands

ABSTRACT

VAN KONINGSVELD M and MULDER JPM 2004 Sustainable coastal policy developments in the NetherlandsA systematic approach revealed Journal of Coastal Research 20(2) 375-385 West Palm Beach (Florida) ISSN 0749-0208

Policy development is a dynamic and cyclic process characterised by successive stages of development implementationand evaluation Throughout this process interaction between science and coastal management plays an importantrole An illustration is given in this paper based on an analysis of the history of coastal policy in the Netherlandsover the last two decades Evaluation in 1995 of the coastal policy of Dynamic Preservation developed during the late80rsquos and implemented in 1990 led to a redefinition in 2000 Implementation in 2001 of a sustainable coastal policyin the Netherlands with both a small- and a large-scale approach is the result

The analysis in this paper indicates that the successful development and implementation of coastal policy in theNetherlands is related to the use of a systematic lsquoframe of referencersquo characteristics are explicit definitions of bothstrategic and operational objectives applied in a 4-step decision recipe of (1) a quantitative state concept (2) a benchmarking procedure (3) a procedure for CZM measures or intervention and (4) an evaluation procedure Applicationsof this frame of reference show its high potential to better integrate coastal science and coastal policy and -manage-ment and to stimulate co-operation

ADDITIONAL INDEX WORDS Coastal policy strategic and operational objectives bench marking evaluation frameof reference nourishments sand balance time and space scales sustainability research management coastal manage-ment coastal science communication end users gap

INTRODUCTION

Since the beginning of the 20th century coastal manage-ment increasingly relies on science in the development of so-lutions to coastal problems Literature shows however thatan effective interaction between coastal science and coastalmanagement is not trivial (ao EU 1999 MULDER et al2001 VAN KONINGSVELD 2003) Researchers on the onehand are often of the opinion that their knowledge is noteffectively implemented in practice End users of specialistknowledge on the other hand often claim that research find-ings can not or not easily be put to practical use A multi-tude of reasons for an ineffective transfer of knowledge hasbeen proposed including a lack of consideration for the needsof end users by scientists unclear formulation of manage-ment problems lack of funding time effort and skills Thecauses suggested so far however do not provide a satisfac-tory explanation for nor a constructive approach to deal withthe limited use and usefulness of coastal engineering re-search as it has been perceived in practice

03-0011R received 18 February 2003 accepted in revision 23 June2003

VAN KONINGSVELD et al (2003) suggest lsquoa divergence inthe perceptions of coastal specialists and users of specialistknowledge of the problem at hand and the information thatis needed to deal with itrsquo as a fundamental mechanism re-sponsible for increasing incomprehension in the co-operationbetween science and coastal management To defuse thismechanism they suggest an increased involvement of end us-ers in order to produce information that can be used in coastrelated decision processes A crucial step to achieve this isto create a common perspective on a coastal managementproblem that needs to be solved For this purpose MULDER

et al (2001) have suggested to define the essential elementsof a coastal management problem as explicitly as possibleJoint identification of essential decision elements will pro-mote the development of a shared perspective The explicitelements subsequently constitute a framework that both sci-entists and coastal managers or policy makers can refer toThroughout this paper this collection of explicit elements as-sociated with a given problem will be referred to as the lsquoframeof referencersquo Application of this lsquoframe of referencersquo as a toolfor communication about coastal management problems willbe indicated as the lsquoframe of referencersquo-methodology

Obviously concrete implementation of this methodology

376 Van Koningsveld and Mulder

Journal of Coastal Research Vol 20 No 2 2004

Figure 1 Orientation on the coast of Netherlands and its three sub-regions

may yield different results per management problem per pro-ject type and even per project phase To get an idea of somelsquobasicrsquo elements generally associated with workable manage-ment solutions the crucial ingredients of the lsquoDynamic Pres-ervationrsquo policy in the Netherlands successfully implementedsince over 10 years are analysed in this paper After a gen-eral description of the Dutch coast and coastal policy thebasic elements constituting the lsquoframe of referencersquo for theDynamic Preservation policy since 1990 are revealed Finallydemonstrating the usefulness of an explicit lsquoframe of refer-encersquo in the development of a new sustainable coastal policyin the Netherlands the potential of this systematic approachto improve co-operation between science and coastal manage-ment is illustrated

NORTH SEA COAST OF THE NETHERLANDS

The Dutch coastline along the SE part of the North Sea isabout 350 km long (see Figure 1) Commonly the Dutch coastis divided into three regions viz (1) the Delta coast in thesouth (2) the Holland coast in the centre and (3) the Waddencoast in the north The morphology of the Delta coast is dom-inated by tides The morphology of the Holland coast betweenHoek van Holland and Den Helder is typically a storm-dom-inated sandy coast The Wadden coast is characterised by thepresence of barrier islands and from a morphological view-point somehow comparable to the Delta coast Some 15 of

the coast consists of sea dykes and other man made sea bar-riers 10 consists of beach flats along the tips of the north-ern Wadden islands and 75 consists of dune areas of vary-ing widths ranging from less than 100 meters to several kilo-metres The primary function of the coast is to protect thelow-lying hinterland from flooding The sandy coast howeverrepresents important value to other functions as well egecological value drinking water supply recreation residen-tial and industrial functions Coastal erosion dominant alonghalf of the Dutch coast is endangering these functions

COASTAL POLICY

Traditionally coastal policy in the Netherlands concernedsafety from flooding After the storm surge disaster of 1953coastal policy was dominated by the objective to bring all seadefences to a predefined safety level the so-called deltastrength Implementation took place in the Delta ProjectDuring the 60rsquos 70rsquos and 80rsquos of the last century dikes anddunes were strengthened and tidal inlets in SW Netherlandswere closed by dams From the mid 70rsquos the policy perspectiveof the Delta Project gradually widened Ecological argumentswere included in decision making As a result closure of theEastern Scheldt tidal inlet in 1986mdashclimax of the Delta Pro-jectmdashwas decided to be an open storm surge barrier Simi-larly during the 80rsquos the scope of coastal policy graduallyextended towards other functions Once the Delta safety lev-

377A Systematic Approach to Policy Development


Figure 2 A basic frame of reference for policy development (Source VAN

KONINGSVELD 2003)

Figure 3 Calculation of Momentary Coastline MCL (Source MIN VampW1991)

els had been established along the coast structural coastalerosion problems received increasing attention The need tomaintain structural integrity of the coast in order to ensuresustainability of all coastal functions called for a new coastalpolicy

DYNAMIC PRESERVATION OF THE COASTLINE

In order to stop any further structural recession of thecoastline the Dutch government initiated the development ofa new coastal policy at the end of the 80rsquos To arrive at dif-ferent policy options and to enable rational decision makinga large study was commissioned involving many of the Dutchcoastal researchers (cf VAN KONINGSVELD et al 2003)Based on this study the Dutch Government adopted in 1990the national policy of lsquolsquoDynamic Preservationrsquorsquo (MIN VampW1990) The strategic objective was to guarantee a sustainablesafety level and sustainable preservation of values and func-tions in the dune area The specification of a set of operationalaspects promoted an easy implementation First of all thespecification of a clear operational objective the coastline willbe maintained at its position in the year 1990

An analysis of the implementation phase of lsquolsquoDynamic Pres-ervationrsquorsquo based on successive policy documents (MIN VampW1990 1996 2000 2002) and on several authors eg HILLEN

and DE HAAN (1993) ROELSE and HILLEN (1993) TAW(1995) DE RUIG (1998) and ROELSE (1996 2002) indicatesthatmdashimplicitlymdashimplementation has been guided by thespecification of a decision recipe defining

(1) a quantitative concept of the actual state of the system(2) procedures for objective benchmarking(3) procedures for preferred interventions and(4) procedures for evaluation

The strategic- and operational objectives together with thedecision recipe constitute what in this paper is referred toas the basic operational lsquoframe of referencersquo for the DynamicPreservation policy (see Figure 2)

An illustration of the elements in the decision recipe of lsquolsquoDy-namic Preservationrsquorsquo is given in the following sections withreference to TAW (1995) The quantitative evaluation of theireffectiveness is mainly based on the work by ROELSE (2002)

Quantitative State Concept the Momentary Coastline

The first element of the decision recipe for coastline man-agement is an objective assessment of the state of the systemFor this purpose the concept of the Momentary Coastline(MCL) has been developed defining the coastline position asa function of the volume of sand in the near shore zone Thecalculation of the MCL in any given cross-shore profile isbased on the area (or volume per unit length) of sand betweentwo horizontal planes (MIN VampW 1991) The upper and lowerboundaries are each located at a distance lsquoHrsquo from the MeanLow Water Level (MLWL) where lsquoHrsquo denotes the vertical dif-ference between the dune foot and the mean low water level(see Figure 3)

The lsquoactualrsquo calculation of the MCL is based on data fromthe Dutch yearly coastal monitoring program (JARKUS)which has been operational since 1963 JARKUS measurescoastal depth profiles from the first dunes up to 1 km in aseaward direction at alongshore intervals of 250 m

Benchmarking Procedure

Next a benchmarking procedure was developed aimed atan objective assessment of erosion problems of a structuralnature For this purpose a predefined reference state needs tobe described and compared with the observed (or predicted)system state Basic building block of these state descriptionsis the quantitative state concept MCL

The Basal Coastline

The operational objective to maintain the coastline at its1990 position implies a reference state related to the 1990coastline As such the Basal Coastline (BCL) has been definedas the estimated position of the coastline on January 1st of1990 The BCL position is derived from an extrapolation ofthe linear trend in positions of the 10 MCL-points during theyears 1980 to 1989 (Figure 4) The choice for a 10 year linear



Figure 4 Procedure to define the Basal Coastline BCL (resp the Test-ing Coastline TCL) Figure 5 Definition sketch for nourishment design per unit length of

coastline (Based on ROELSE 2002)

trend extrapolation was inspired by the objective to counterstructural rather than incidental erosion

The Testing Coastline

Similarly accounting for structural erosion the descriptionof the actual state of the system is based on a so-called Test-ing Coastline (TCL) The position of the TCL is determinedin a similar way as the BCL by linearly extrapolating thetrend of coastline positions (MCL) of ten previous years Thusthe position of the TCL in the year T can be determined bylinearly extrapolating on the calculated MCL positions in theyears (T-10) until (T-1) (Figure 4)

The state of the system can now be compared with the ref-erence state by comparing the TCL position with the BCLposition This comparison provides an indication for the (ex-pected) coastal state in the year T A TCL that moves land-ward of the BCL represents a signal to the responsible coastalauthority to consider intervention

Intervention Procedure Sand Nourishment

The name lsquolsquoDynamic Preservationrsquorsquo refers to the preferredapproach to achieve the policy objectives Dynamic Preser-vation implies the goal to make optimal use of natural pro-cesses Consequently the principal intervention procedure issand nourishment

Design procedure

Sand nourishment over the last decade has become an ac-cepted practice in coastal management worldwide Useful in-formation on international shore nourishment experience ispresented eg by DAVISON et al (1993) CPBN (1995) CEM(2002) HAMM et al (2002) and DEAN (2002) Focussing on theNetherlands the design procedure for a nourishment with apredetermined lifespan is best illustrated by the following fic-titious example (after TAW 1995 and ROELSE 2002)

Assume over the last 10 years (dt) a given coastal stretchis eroding over a length of 1000 m (dy) at an average rate of

1 myear (d XMCLd t linear trend determined from 10 MCL po-sitions) Then a basic design of a shoreface nourishment witha projected lifespan of 5 years (Tlife) would be the result ofapplying the following procedure (see also Figure 5)

First of all it is acknowledged that the MCL method onlyuses a limited part of the upper shoreface to determine thecoastline position Assuming that the MCL trend is represen-tative of the trend for the total active depth of the profile (D)and assuming that the active depth is 20 m the total volume(V) per unit length of coastline eroding annually from eachcross-shore transect is (see Figure 5a)

dV dXMCL 35 3 D 5 20 m myear (1)dt dt

The product of the annually eroded volume and the projectedlifespan (Tlife) yields the total expected volume (Vtot) to beeroded during the performance lifetime (see Figure 5c)

dV3V 5 3 T 5 20 m myear 3 5 yearstot lifedt

35 100 m m (2)

To make sure the intervention is effective usually a loss-factor (f) is applied which accounts for the uncertainties as-sociated with the design procedure as well as the governingnatural processes For the Dutch case ROELSE (2002) sug-gests a factor f in the range of 11 to 15 for beach nourish-ment In case of a shoreface nourishment a factor of roughly2 is suggested to obtain the required nourishment volume(Vnour) (see Figure 5c)

3 3V 5 V 3 f 5 100 m m 3 2 5 200 m m (3)nour tot

The product of this Vnour and the alongshore length of theeroding stretch (dy) yields the total nourishment volume(Vnourtot)

3V 5 V 3 dy 5 200 m m 3 1000 mnourtot nour

35 200000 m (4)



Figure 6 Percentage of coastal transects with a BCL-transgression inthe Netherlands and in the coastal regions (Source ROELSE 2002)

Figure 7 Changes in lsquolsquosafety from floodingrsquorsquo indicated by the trend inposition of the lsquoerosion pointrsquo over the period 1981ndash1997 relative to itsposition in the year 1990 (m) averaged for the situations at 7 weak linksin the Dutch coastal defence (viz Callantsoog Delfland Schouwen-Noor-derstrand Schouwen-Kop Walcheren-Noordwestkust Walcheren-Zuidwestkust and Zeeuwsch-Vlaanderen) (Source ROELSE 2002)

Figure 8 Developments in the lsquolsquovulnerability levelrsquorsquo in the coastal zoneindicated by changes in distance (m) between the lsquoerosion pointrsquo and spe-cific vulnerable objects over the period 1980ndash1998 relative to the distancein 1990 and averaged for 6 specific objects along the Dutch coast (3 hotels1 resort and 2 boulevards) (Source ROELSE 2002)

Figure 5c shows that this nourishment volume may be cor-rected by a volume (Vr) representing either a reduction incases of a remaining sand buffer or an addition in caseswhere the TCL already surpassed the BCL The geographicaldesign aspects are determined by specific characteristics ofthe eroding stretch

Evaluation of Policy Effectiveness

Periodic evaluation of policy effectiveness is recommendedMIN VampW (1990) prescribes a 5-year interval for evaluation

EVALUATION OF DYNAMIC PRESERVATION

Since 1990 several evaluations of single nourishmentevents (ROELSE and HILLEN 1993) and the coastline policyas a whole (cf ROELSE 1996 2002 DE RUIG 1998) havebeen presented

Considering the operational objective to preserve the coastlineat its 1990 position a quantitative evaluation leads to a clearconclusion lsquolsquoDynamic Preservationrsquorsquo has been successful overthe period of 1991ndash2000 With a yearly average of 6 Mm3 ofsand nourishments over the last decade ROELSE (2002) statesthat there is no more coastal retreat and the number of tran-sects exceeding the BCL is decreasing yearly (see Figure 6)

With respect to the strategic objectives viz to guarantee asustainable safety level and sustainable preservation of val-ues and functions in the dune area the lacking of explicitguidelines for benchmarking of effectiveness hampers an ob-jective evaluation Howevermdashas shown by ROELSE (2002)and illustrated in the following sectionsmdashevaluations of de-velopments in safety levels and in values and functions of thedune area show positive indications To a lesser extent thesame accounts for sustainability

Safety Levels

Within the Dutch context the level of safety generally im-plies two components viz lsquosafety from floodingrsquo dealing withthe inundation of the hinterland due to failing flood defencesand lsquovulnerability risk of propertyrsquo dealing with damage dueto wave action andor erosion Along the Dutch sandy coastboth are depending on the strength of dunes In Dutch coastalpolicy strength of dunes is determined with a quantitative

state concept referred to as the lsquoerosion pointrsquo This point re-presents the ultimate landward extent to which a dune isexpected to erode given a certain coastal profile and a set ofnormative hydrodynamic boundary conditions (TAW 1995)

To objectively evaluate the effectiveness of Dynamic Pres-ervation in preserving lsquosafety from floodingrsquo ROELSE (2002)determined the evolution of the lsquoerosion pointrsquo at 7 knownweak locations at the Dutch sandy coast After introductionof the policy in 1990 a clear seaward shift of the lsquoerosionpointrsquo has been observed with an averaged 20 m (Figure 7)A shift (for the most part) consolidated throughout the 90rsquosillustrating an averaged increase in the level of lsquosafety fromfloodingrsquo

The effect of Dynamic Preservation on the lsquovulnerability ofpropertyrsquo in the coastal zone is objectively estimated byROELSE (2002) based on the distance between the lsquoerosionpointrsquo and vulnerable objects in the coastal zone For six lo-cations (3 hotels 1 resort and 2 boulevards) the positions ofthe lsquoerosion pointsrsquo were calculated for a storm surge with anexceedance frequency of the high water level of 1500 peryear a condition that is also applied in relation to buildingpermits Figure 8 shows the results over the last two decades



Table 1 Evaluated recreation areas in different regions along the Dutchcoast (after Roelse 2002)

Region Recreation Area IDnr

Wadden Coast SchiermonnikoogAmelandTerschellingVlielandTexel

12ndash45ndash91011

Holland Coast Noord-HollandRijnlandDelfland

12ndash1415ndash1819ndash24

Delta Coast VoorneGoereeSchouwenNoord-BevelandWalcherenZeeuws Vlaanderen


3637ndash4041ndash44 Figure 9 Developments in dry beach widths (distance from dune foot

(DF) and Mean High Water Line (MHWL) over the period 1990ndash1998(a) aggregated for the Netherlands (b) per recreation area in differentregions along the coast (cf Table 1) (Source ROELSE 2002)averaged for the six locations The general trend before 1990

was negative the positive shift in 1984 is the result of a nour-ishment on the island of Texel near one of the objects Thetrend after 1990 is clearly positive

Values and Functions in the Dune Area

Focusing on the recreational function and on the naturalvalues of the dune area ROELSE (2002) has evaluated de-velopments in beach characteristics and in dune area

To evaluate the development of recreational beach widthROELSE (2002) uses as a quantitative state concept the lsquodrybeach widthrsquo defined as the distance from the Mean HighWater Level (MHWL) to the intersection of the dune frontwith the NAP 13 m contour (NAP Normaal AmsterdamsPeil is Dutch Ordnance Level approximately equal to MeanSea Level) The lsquodry beach widthrsquo was evaluated for the years1990 and 1998 at 44 recreational areas along the coast to-gether making up approximately 30 of the entire length ofthe coastline (Table 1) In 28 of these areas one or more nour-ishments have been applied in this period Figure 9a showsthat the averaged width of all lsquodryrsquo recreational beaches in-creased with approximately 10 m between 1990 and 1998Considering the 44 investigated areas only 5 areas show adecrease in width of more that 10 m (Figure 9b) Howevernone of these areas received nourishment in the period be-tween 1990 and 1998

To quantify the effects of the nourishment policy on thetotal dune area ROELSE (2002) uses the quantitative stateconcepts lsquodune footrsquo-position and lsquodune frontrsquo-position Theseaward delimitation of the dune area is the dune foot whichis marked by the transition of lsquoflatrsquo beach to the lsquosteeprsquo dunefront To get consistent time series and to avoid the mostintensive dynamics the lsquodune foot positionrsquo is chosen rela-tively high at a fixed height of NAP 13 m in the JARKUSprofile The lsquodune front positionrsquo is chosen at the NAP 16 mcontour The chosen method limits the analysis to seawardchanges of the dune area A reasonable assumption as thelandward changes in the dune area have proven to be mar-ginal Figure 10a shows the changes for the periods 1980ndash1990 and 1990ndash1998 aggregated for the three coastal regionsand expressed in terms of changes in dune area above the

lsquodune footrsquo and lsquodune frontrsquo respectively All regions show in-creases in the dune area with the largest response for thedune foot The Holland coast shows a small decrease over theperiod 1980ndash1990 changing into a gain of dune area of app230 ha over the period 1990ndash1998 Figure 10b shows thesame changes but in this case specified for the coastal sec-tions indicated in Table 1 Again the figures based on lsquodunefoot positionrsquo show the largest changes in dune area as is tobe expected The island of Texel shows the most remarkablechange A loss of 85 ha in the period 1980ndash1990 changed intoa gain of 95 ha over the last decade

ROELSE (2002) interprets the lsquodry beach widthrsquo and thelsquodune arearsquo as indicators of the state of the functions lsquorecre-ationrsquo and lsquonaturersquo However whether the selected indicatorsare representative for the development of these functions orall values and functions in the dune area for that matter isquestionable Such conclusion would require a further speci-fication of the values and functions included in the strategicobjective The same accounts for the element of the strategicobjective dealing with sustainability All positive indicationsof the policy effectiveness as cited above regard the period1991ndash2000 (ROELSE 2002) Does this imply that DynamicPreservation is a sustainable policy

Sustainability

Discussing sustainability requires making time- and spacescales explicit Typical scales involved in the Dynamic Pres-ervation policy are implied by the operational frame of ref-erence

The definition of the quantitative state concept MCL in-volves specific spatial and temporal resolutions It assumesthat the most important changes in the coastal profile withinthe course of one year occur between the upper- and lowerplanes of the definition sketch (Figure 3) As a result thetypical vertical scale of analysis is 10 to 15 m ranging fromdune foot to approximately 212 m The alongshore resolutionis determined by the 250 m spacing interval of the yearlymonitoring program JARKUS Consequently the yearly de-



Figure 10 Developments in dune area (ha) during the periods 1980ndash1990 and 1990ndash1998 at the dune foot (NAP 1 3 m) and at the dune front (NAP1 6 m) (a) aggregated for the three coastal regions of the Netherlands (b) per separate coastal section (Source ROELSE 2002)

termination of MCL positions can detect alongshore coastalchanges with an order of magnitude of kilometres while itleaves smaller scale and intra year changes undetected Thebenchmarking procedure of BCL and TCL is designed to com-pensate for structural erosion with a time frame of 10 yearsFinally the nourishment design procedure extrapolates thechanges observed in the upper part of the profile (BCL-zone)to an assumed active profile reaching to 220 m depth Nour-ishments typically are designed with an alongshore scale inthe order of kilometres in a depth interval of 13 to 26 mand average design life span of 5 years

As a whole the BCL methodology is generally associatedwith time scales of 1 to 10 years alongshore space scales inthe order of 1 to 10 kilometres and cross shore space scalesof dune foot to approximately 212 m During the last decadeimplementation of the Dynamic Preservation policy charac-terised by an average nationwide nourishment budget of 6

Mm3 of sand per year has successfully preserved the coast-line at the 1990 position (ROELSE 2002) in other words overthe last ten years Dynamic Preservation has succeeded inpreserving the total sand volume in the upper shore faceCombining this conclusion with the typical scales involvedindicates that

the Dynamic Preservation approach as applied since1990 might be considered sustainable at a time scale of10 years

However does this imply that the same approach will besustainable at larger time scales as well

The answer would be positive if a preservation of sand vol-ume could be demonstrated over a larger time scale Largertime scales however likewise imply larger space scales Asindicated eg by NICHOLLS et al (1998) the seaward limit ofsignificant depth changes (the depth of closure) shifts in an



offshore direction with time Unfortunately estimates of thedepth of closure at larger time scales are rare due to lack ofdata The JARKUS database covering the Dutch coast to adepth of 28 to 212 m on a yearly basis since 1965 deliverssome indications In a study of the Holland coast (see Figure1) HINTON (2000) concluded that on a time frame of 32 yearssome 25 of the JARKUS sections showed a fully active orseaward active profile Apparently for these sections thedepth of closure on a time scale of 32 years must be some-where deeper than 212 m On this basis MULDER (2000) as-sumed a depth of closure for the total Dutch coastal systemof 220m (relative to Mean Sea Level) considering a timeframe of 30ndash50 years Then he derived a long term sand bal-ance of the coastal system from available sounding data Overthe period 1965ndash1995 MULDER (2000) shows a negative sandbalance in the Dutch coastal system of 24 to 210 Mm3 peryear relative to the fixed Dutch Ordnance Level (NAP) Inaddition to this the effect on Mean Sea Level of a sea levelrise of 20 cm per century appears responsible for anothersand loss from the active coastal system of 28 Mm3 per yearThus the total sand balance of the Dutch coastal systemdefined as the area between dunes and 220 m below MLWLover the period 1965ndash1995 is estimated to range from 26 to213 Mm3 per year Extrapolating the long term trends andcompensating for a sea level rise of 20 cm per century MUL-DER (2000) estimated for the coming decennia an increase inthe deficit of the sand balance up to a maximum of 210 to216 Mm3 per year

Comparison of these long term figures with the current av-erage yearly nourishment volume of 6 Mm3mdashthe amount sup-plied to the Dutch coastal system according to the BCL ap-proach of the Dynamic Preservation policy during the lastdecademdashleads to the following conclusions

bull the present nourishment design procedure does NOT de-liver representative estimates of sand volume changes inthe total coastal system

bull the yearly nourishment volume according to the presentpolicy is NOT sufficient to preserve the total sand volumeof the Dutch coastal system and thus

bull the Dynamic Preservation approach as applied since1990 is NOT sustainable at larger scales

The conclusions of this evaluation as first indicated in MIN

VampW (1996) have led to a redefinition of the Dynamic Pres-ervation policy introducing a large scale approach on top ofthe existing small scale approach and extending the availablefinancial resources (MIN VampW 2000) The following sectionillustrates the new sustainable policy

SUSTAINABLE COASTAL POLICY A SMALL- ANDLARGE SCALE APPROACH

Regarding 30ndash50 years a relevant time scale for a sustain-able policy the matching space scale for coastal policy is con-sidered to be the sandy coastal system from dunes down to adepth of 220 m Safety levels against flooding as well as thequality of other values and functions in this sandy coastalsystem are depending on the total amount and spatial dis-tribution of the sand In fact the total amount of sand deter-

mines the potential whereas the distribution determines theactual status of the various values and functions in the coast-al zone

Considering preservation of the potential of various valuesand functions as the first basic condition for sustainability alogical first operational objective of a redefined sustainablecoastal policy is (MULDER 2000)(1) Preservation of the Total Sand Volume in the Coastal System

Basically this implies a large-scale approach The actualstatus of values and functions in the coastal zone is deter-mined by the distribution of sand Preservation of values andfunctions on a time scale of 1 to 10 years has proven to bequite effective using the BCL approach of Dynamic Preser-vation (ROELSE 2002) Thus a logical second operational ob-jective of a redefined sustainable coastal policy remains(2) Maintaining the Coastline at its Position in the Year 1990

This (relatively) small scale approach supplemented by thelarge scale approach characterises the redefined sustainablecoastal policy in the Netherlands as implemented in 2001(MIN VampW 2000) From 2001 the Netherlands has raisedthe total nourishment volume in its coastal system from anaverage of 6 to an average of 12 Mm3 per year The nourish-ment budget has been raised from 27 to 41 million Euro peryear

Implementation

The operational frame of reference developed for the (rel-atively) small scale approach of the Dynamic Preservationpolicy provides a template for the implementation of the newlarge scale approach First of all a quantitative state concepthas been defined (MULDER 2000) The next steps in theframework still have to be developed However there is nodiscussion on the preferred intervention procedure sandnourishments

Quantitative State Concept Large Scale Coastal Cells

On a time scale of 30ndash50 years the cross shore space scaleismdashas indicated earliermdashassumed to range from dunes downto 220 m The corresponding alongshore space scale is as-sumed to be several tens of kilometres The specific morpho-logic regions of the Holland coast bound by anthropogenicfeatures as derived from decadal behaviour (see WIJNBERG1995 WIJNBERG and TERWINDT 1995) may be consideredtypical sub-systems at this time scale The same accounts forthe separate tidal systems in the Wadden- and the Deltaarea Thus MULDER (2000) defined nine large coastal cellsrepresenting the Dutch coastal system on the time scale ofdecades (Figure 11)

DISCUSSION AND CONCLUSIONS

The review of coastal policy in the Netherlands over thelast two decades presented in this paper indicates gradualchanges in both the policy perspective and in the process ofpolicy development itself and illustrates the role and impor-tance of co-operation between science and coastal management



Figure 11 Nine large scale coastal cells in the Dutch coastal system(Source MULDER 2000)

Figure 12 The basic frame of reference as a tool for policy development and for communication between science and coastal management

Policy Perspective

The dominant focus of coastal policy on safety from flood-ingmdashalthough still number one prioritymdashgradually hasbeen extended to all values and functions in the coastalzone The strategic objective of Dynamic Preservation (MIN

VampW 1990) mentions lsquolsquo safety level and function andvalues in the dune area rsquorsquo and introduced lsquolsquo sustainablepreservationrsquorsquo Implementation from 1990 based on the op-erational objective lsquolsquo to maintain the coastline rsquorsquo fo-cussed on a relatively small scale BCL-approach Discus-sions on larger scale effects (eg sand losses at larger depthsor so-called coastal steepening and long term developmentslike sea level rise MIN VampW 1996) triggered a

(re)consideration of the dimensions of lsquolsquosustainabilityrsquorsquoWithout changing the strategic objective the result hasbeen the redefinition of a sustainable coastal policy intro-ducing a supplementary large scale- to the existing smallscale approach (MIN VampW 2000) The new policy introduceda second larger scale operational objective Present daydiscussions on integrated coastal zone management (MIN

VampW 2002) illustrate a further widening of the perspectivewith a tendency to rephrase the strategic objective of coastalpolicy exchanging lsquolsquodune arearsquorsquo by lsquolsquocoastal zonersquorsquo

Process of Policy Development Co-Operation betweenScience and Coastal Management

The changes in policy perspective are closely interlinkedwith the process of policy development The history of the lasttwo decades illustrates the cyclic pattern of policy develop-ment After the development stage in the 80rsquos (MIN VampW1990) follows the implementation stage during the begin-ningmdashand an evaluation stage during the end of the 90rsquos(MIN VampW 1996) The cycle is renewed in 2001 by imple-mentation of a redefined policy (MIN VampW 2000)

An important factor during all stages of coastal policy de-velopment in the Netherlands over the last decade has beenthe (implicit) use of an operational lsquoframe of referencersquo char-acterised by a specified decision recipe including a cyclicevaluation of both explicit operational- and strategic objec-tives

Its practical use during the implementation stage of coastalpolicy is illustrated by the successful implementation of theDynamic Preservation policy since 1990 Analogously an ex-plicit use of this lsquoframe of referencersquo gives strong guidelinesfor the steps towards a smooth implementation of the newsustainable coastal policy after the definition of coastal cellsas quantitative state concept it is clear that a bench markingtest and a design procedure for interventions need furtherelaboration Necessary studies first revealed a need for ad-ditional data As a result the large scale coastal cell concepthas invoked an extension of the yearly monitoring programof the near shore zone (JARKUS) with a 5-yearly monitoringof the coastal system down to a depth of 220 m The designof a benchmarking procedure has already triggered a firstsubject for evaluation The definition of the large scale coastalcells more specifically the cross- and long shore boundariesof the cells may be considered as explicit management hy-potheses asking for scientific scrutiny Thus the systematic



approach stimulates the transfer of expert knowledge in sup-port of coastal policy

Similarly to the implementation stage the lsquoframe of ref-erencersquo-approach has proven its use for the other stages ofpolicy development The development of the new sustain-able coastal policy provides a good illustration The notionin the frame of reference of the need to break down stra-tegic objectives into one or more operational objectives (seeFigure 12) expressed in terms of quantitative state con-cepts eg has resulted in useful discussions on the dimen-sions of the sustainability concept resulting in the new sus-tainability policy

In a similar way the lsquoframe of referencersquo-approach may behelpful in further analyses of the strategic objective of thecoastal policy eg by specifying quality indicators and scalesassociated with specific other values and functions in thecoastal zone The BCL- and large scale coastal cell conceptfor example operate at time scales of 1 to 10 and 10 to 100years respectively These scales are large compared with thescales of interest for eg beach recreational purposes con-fronted with seasonal and much more local changes of thecoastal system Thus for specific recreational interests thedefinition of a new operational objective may be requiredaccompanied by a decision recipe designed at a more suitablescale

In this context the specific nature of the relatively suc-cessful operational objectives (1) to preserve the total sandvolume in the coastal system and (2) to maintain the coast-line position must be noted Both operational objectives focuson basic physical characteristics of the system Both aim toprovide boundary conditions for a favourable development ofvalues and functions as specified on a strategic level For ac-tual development of these functions and values coastal policyand management tend to rely on the systemrsquos ability for self-organisation

Finally it is concluded that a more systematic approach topolicy development will call upon (and stimulate) a better co-operation between science and coastal management An op-timisation of the co-operation is in the interest of both com-munities The amount of resources invested in coastal re-search and the interests looked after by coastal managersand coastal policy makers justify the efforts to this effect Thework in this paper illustrates how to facilitate effective re-search- and technology transfer to the coastal managementsector and how in this context the lsquoframe of referencersquo-ap-proach represents a promising tool to stimulate communica-tion between coastal managers and coastal scientists of dif-ferent disciplines

ACKNOWLEDGEMENTS

The work was carried out in the framework of the Rijks-waterstaat Coastal Research programmes KUST2000 andKUST2005 The analysis of the process of policy develop-ment with special attention to the relationship between re-searchers and coastal managers was part of the joint Pro-grading Research Programme (VOP) of RWS National Insti-tute for Coastal and Marine ManagementRIKZ and WL zDelft Hydraulics Part of the work was conducted in the EU

project CoastView (projnr EVK3-CT-2001-00054) and partin a PhD project at the Civil Engineering and Managementdepartment of the University of Twente funded by the Dr irCornelis Lely Stichting Both authors acknowledge the Neth-erlands Centre for Coastal Research (NCK)

LITERATURE CITED

CEM (COASTAL ENGINEERING MANUAL ONLINE) 2002 httpbigfootwesarmymilcem026html

CPBN (COMMITTEE ON BEACH NOURISHMENT AND PROTECTION)1995 Beach Nourishment and Protection National Research Coun-cil Washington National Academy Press 334 p

DAVISON TA ULRICH CP and NICHOLLS RJ 1993 Accredi-tation of Beach Nourishment Projects an Issues Discussion Shoreand Beach Journal of American Shore and Beach Preservation As-sociation 61 (4) 9ndash15

DEAN RG 2002 Beach Nourishment Theory and Practice WorldScientific Advanced Series on Ocean Engineering Vol 18

EU (EUROPEAN UNION) 1999 Lessons learned from the EuropeanCommissionrsquos Demonstration Programme on Integrated CoastalZone Management Report Office for official publications of theEuropean Communities

HAMM L CAPOBIANCO M DETTE HH LECHUGA A SPANHOFFR and STIVE MJF 2002 A summary of European experiencewith shore nourishment Journal of Coastal Engineering 47(2002) 237ndash264

HILLEN R and DE HAAN TJ 1993 Development and Implemen-tation of the Coastal Defence Policy for the Netherlands In HIL-LEN and VERHAGEN (eds) Coastlines of the Southern North SeaNew York ASCE ISBN 0-87262-967-8 pp 188ndash201

HINTON C 2000 Decadal Morphodynamic Behaviour of the Hol-land Shoreface PhD Thesis Flood Hazard Research Centre Mid-dlesex University United Kingdom

MIN VampW 1990 Coastal Defence after 1990 a Policy Choice forCoastal Protection 1st Coastal Policy Document Ministry ofTransport Public Works and Watermanagement The HagueNL

MIN VampW 1991 De basiskustlijn een technischmorfologischeuitwerking (in Dutch)

MIN VampW 1996 Coastal Balancemdash1995 2nd Coastal Policy Docu-ment Ministry of Transport Public Works and Watermanage-ment The Hague NL

MIN VampW 2000 Tradition Trends and Tomorrow 3rd Coastal Pol-icy Document Ministry of Transport Public Works and Water-management The Hague NL

MIN VampW 2002 Naar integraal kustzone beleid beleidsagenda voorde kust Policy Agenda on Integrated Coastal policy Ministry ofTransport Public Works and Watermanagement The Hague NL(In Dutch)

MULDER JPM 2000 Zandverliezen in het Nederlandse kustysteemAdvies voor Dynamisch Handhaven in de 21e eeuw Report RIKZ-200036 National Institute for Marine and Coastal Management(RIKZ) The Hague NL (In Dutch)

MULDER JPM VAN KONINGSVELD M OWEN MW and RAW-SON J 2001 Guidelines on the selection of CZM ToolsmdashIllustratedby applications to CZM problems on straight sandy coasts and onirregular coasts Report RIKZ2001020 EU Mast projectCOAST3D Proj no MAS3-CT97-0086

NICHOLLS RJ BIRKEMEIER WA and LEE GUAN-HONG 1998Evaluation of depth closure using data from Duck NC USA Ma-rine Geology 148 179ndash201

ROELSE P and HILLEN R 1993 Evaluatie van zandsuppletieseen morfologische beschouwing Interim report DGW-93054 (InDutch)

ROELSE P 1996 Evaluatie van zandsuppleties aan de Nederlandsekust 1975ndash1994 een morfologische beschouwingrsquorsquo Report RIKZ-96028 ISBN 90-369-0455-2 RIKZ Middelburg (In Dutch)

ROELSE P 2002 Water en Zand in Balans Evaluatie zandsuppletiesna 1990 een morfologische beschouwing Report RIKZ-2002003ISBN 90-36-369-3426-5 (In Dutch)



DE RUIG JHM 1998 Coastline Management in The NetherlandsHuman use versus natural Dynamics Journal of Coastal Conser-vation 4 127ndash134

TAW (TECHNISCHE ADVIESCOMMISSIE VOOR DE WATERKERINGEN)1995 Basisrapport zandige kust behorende bij de leidraad zandigekust (in Dutch)

VAN KONINGSVELD M 2003 Matching Specialist Knowledge withEnd User Needs PhD Thesis University of Twente EnschedeThe Netherlands ISBN 90-365-1897-0

VAN KONINGSVELD M STIVE MJF MULDER JPM DE VRIEND

HJ RUESSINK BG and DUNSBERGEN DW 2003 Usefulnessand Effectiveness of Coastal Research A Matter of PerceptionJournal of Coastal Research 19(2) 441ndash461

WIJNBERG K 1995 Morphologic Behaviour of a Barred Coast Overa Period of Decades PhD Thesis Utrecht University Utrecht TheNetherlands ISBN 90-6809-211-1

WIJNBERG K and TERWINDT JHJ 1995 Extracting decadal mor-phological behaviour from the high-resolution long-term bathy-metric surveys along the Holland coast using eigenfunction anal-ysis Marine Geology 126 301ndash330

Journal of Coastal Research 20 2 375ndash385 West Palm Beach Florida Spring 2004

Sustainable Coastal Policy Developments in TheNetherlands A Systematic Approach RevealedM van KoningsvelddaggerDaggerlowast and J P M Mulderamp

daggerWLzDelft HydraulicsMarine and Coastal

ManagementPO Box 1772600 MH Delft

The Netherlandsmarkvankoningsveld

wldelftnl

DaggerUniversity of TwenteWater Engineering and

ManagementPO Box 2177500 AE Enschede The

Netherlands

ampRijkswaterstaatNational Institute for

Coastal and MarineManagement RIKZ

PO Box 209072500 EX Den Haag

The Netherlands

Netherlands Centre forCoastal Research NCK

PO Box 1772600 MH Delft

The Netherlands

ABSTRACT

VAN KONINGSVELD M and MULDER JPM 2004 Sustainable coastal policy developments in the NetherlandsA systematic approach revealed Journal of Coastal Research 20(2) 375-385 West Palm Beach (Florida) ISSN 0749-0208

Policy development is a dynamic and cyclic process characterised by successive stages of development implementationand evaluation Throughout this process interaction between science and coastal management plays an importantrole An illustration is given in this paper based on an analysis of the history of coastal policy in the Netherlandsover the last two decades Evaluation in 1995 of the coastal policy of Dynamic Preservation developed during the late80rsquos and implemented in 1990 led to a redefinition in 2000 Implementation in 2001 of a sustainable coastal policyin the Netherlands with both a small- and a large-scale approach is the result

The analysis in this paper indicates that the successful development and implementation of coastal policy in theNetherlands is related to the use of a systematic lsquoframe of referencersquo characteristics are explicit definitions of bothstrategic and operational objectives applied in a 4-step decision recipe of (1) a quantitative state concept (2) a benchmarking procedure (3) a procedure for CZM measures or intervention and (4) an evaluation procedure Applicationsof this frame of reference show its high potential to better integrate coastal science and coastal policy and -manage-ment and to stimulate co-operation

ADDITIONAL INDEX WORDS Coastal policy strategic and operational objectives bench marking evaluation frameof reference nourishments sand balance time and space scales sustainability research management coastal manage-ment coastal science communication end users gap

INTRODUCTION

Since the beginning of the 20th century coastal manage-ment increasingly relies on science in the development of so-lutions to coastal problems Literature shows however thatan effective interaction between coastal science and coastalmanagement is not trivial (ao EU 1999 MULDER et al2001 VAN KONINGSVELD 2003) Researchers on the onehand are often of the opinion that their knowledge is noteffectively implemented in practice End users of specialistknowledge on the other hand often claim that research find-ings can not or not easily be put to practical use A multi-tude of reasons for an ineffective transfer of knowledge hasbeen proposed including a lack of consideration for the needsof end users by scientists unclear formulation of manage-ment problems lack of funding time effort and skills Thecauses suggested so far however do not provide a satisfac-tory explanation for nor a constructive approach to deal withthe limited use and usefulness of coastal engineering re-search as it has been perceived in practice

03-0011R received 18 February 2003 accepted in revision 23 June2003

VAN KONINGSVELD et al (2003) suggest lsquoa divergence inthe perceptions of coastal specialists and users of specialistknowledge of the problem at hand and the information thatis needed to deal with itrsquo as a fundamental mechanism re-sponsible for increasing incomprehension in the co-operationbetween science and coastal management To defuse thismechanism they suggest an increased involvement of end us-ers in order to produce information that can be used in coastrelated decision processes A crucial step to achieve this isto create a common perspective on a coastal managementproblem that needs to be solved For this purpose MULDER

et al (2001) have suggested to define the essential elementsof a coastal management problem as explicitly as possibleJoint identification of essential decision elements will pro-mote the development of a shared perspective The explicitelements subsequently constitute a framework that both sci-entists and coastal managers or policy makers can refer toThroughout this paper this collection of explicit elements as-sociated with a given problem will be referred to as the lsquoframeof referencersquo Application of this lsquoframe of referencersquo as a toolfor communication about coastal management problems willbe indicated as the lsquoframe of referencersquo-methodology

Obviously concrete implementation of this methodology








COASTAL POLICY





KONINGSVELD 2003)















The Basal Coastline












Design procedure








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Safety Levels










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Sustainability



























Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED




































COASTAL POLICY





KONINGSVELD 2003)















The Basal Coastline












Design procedure








35 100 m m (2)


3 3V 5 V 3 f 5 100 m m 3 2 5 200 m m (3)nour tot



35 200000 m (4)













Safety Levels










12ndash45ndash91011














Sustainability



























Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED
































KONINGSVELD 2003)















The Basal Coastline












Design procedure








35 100 m m (2)


3 3V 5 V 3 f 5 100 m m 3 2 5 200 m m (3)nour tot



35 200000 m (4)













Safety Levels










12ndash45ndash91011














Sustainability



























Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED







































Design procedure








35 100 m m (2)


3 3V 5 V 3 f 5 100 m m 3 2 5 200 m m (3)nour tot



35 200000 m (4)













Safety Levels










12ndash45ndash91011














Sustainability



























Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED









































Safety Levels










12ndash45ndash91011














Sustainability



























Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED


































12ndash45ndash91011














Sustainability



























Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED





















































Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED












































Implementation










Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED

































Policy Perspective
















ACKNOWLEDGEMENTS



LITERATURE CITED




































ACKNOWLEDGEMENTS



LITERATURE CITED






































Documents

Sustainable Coastal Policy Developments in The Netherlands. A Systematic Approach Revealed