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Project IJsseldelta, in: International Journal of River Management (2011)


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Project IJsseldelta, in: International Journal of River Management (2011)

Project IJsseldelta, in: International Journal of River Management (2011)

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  • 1. Modern Integrated River Flood Management for Climate Change inthe Netherlands: the IJssel Delta ProjectMARIUS SOKOLEWICZ, DHV B.V., P.O. Box 1132, 3800 BC Amersfoort, theNetherlandsEmail: Marius.Sokolewicz@dhv.comTEUNIS LOUTERS, DHV B.V., P.O. Box 1132, 3800 BC Amersfoort, theNetherlandsEmail: Teunis.Louters@dhv.comARJAN OTTEN, Province of Overijssel, P.O. Box 10078, 8000 GB Zwolle, theNetherlandsEmail: A.Otten@overijssel.nlAbstractThis paper describes a planning process combining river flood management withspatial planning. Within the IJssel Delta project, a river bypass in the river IJssel, oneof the major Dutch rivers, is planned to reduce the risk of flooding in view ofexpected climate change effects. The challenge for this project was to combinevarious developments (bypass, urban development, nature, leisure, infrastructure andagriculture) in the area into a single integrated spatial development plan, acceptable toall stakeholders. This included resolving spatial conflicts between separatedevelopments regarding (i) flood protection, (ii) infrastructure and (iii) housing.During the planning process various bypass alternatives were considered to determinethe span width of possible solutions. Various technical issues related to the bypassdesign have been studied using state-of-the-art methods. A participatory approachinvolving public and private stakeholders has been used to secure a widely accepteddevelopment plan. The plan has been adopted by the responsible authorities. It is nowin the final planning stage and is scheduled for execution from 2013 onwards.Keywords: integrated river flood management, flood protection, spatial planning,participatory approach, collaborative approach, climate adaptation 1
  • 2. 1. Introduction1.1 Modern Integrated River Flood Management This article describes the implementation of modern integrated river floodmanagement in the IJssel Delta project in the Netherlands. Here, a participatory andcollaborative approach involving all relevant stakeholders has been applied. This wascombined with advanced technologies (hydraulic, morphological, geohydrologicalmodelling and probabilistic methods), and legal and economic assessments to pursuean integrated spatial development plan. The main goal of this collaborative approachwas to achieve a sustainable development plan for the future, widely supported by thestakeholders. Within this plan, a bypass will be constructed to adapt the river to theexpected climate change without constraining the urban and infrastructuredevelopment in the area. The participatory approach, defined as “involving allrelevant stakeholders already in early stages of the planning process to achieve widesupport to the resulting spatial development plan” is the basis of the modern spatialplanning and river flood management in the Netherlands (Healey 1997), (VROM2010). Earlier stages of the planning process in the IJssel Delta project were publishedbetween 2005 and 2009 in (Louters et al. 2005), (Hoeven et al. 2007) and (Otten2009).1.2 Project Background The river IJssel in the Netherlands is a major branch of the river Rhine, the 3rdlargest river of Europe. It discharges into lake IJssel, which is a former sea(Zuiderzee), closed off in 1932. The IJssel Delta (Figure 1) is a low-lying area that isthreatened by floods from both the river IJssel and from the lake IJssel. It is protectedfrom flooding by dikes with a high safety standard. The IJssel Delta is mainly anagricultural area, with the city of Kampen (50,000 inhabitants) in its centre. Several major spatial development schemes have been planned for the IJssel Deltafor the coming decades. Kampen plans to expand considerably and build 4,000houses; a new railway line (the “Hanze” line) is under construction, and two highways(N50 and N23) crossing the area will be reconstructed. Furthermore, as one ofmeasures of the national “Room for the River” programme (V&W 2006) aiming atincreasing safety against flooding along the river Rhine branches, construction of a 2
  • 3. bypass diverting a part of flow from the river IJssel during extreme flood conditions isalso planned in this area. All these separate, potentially conflicting spatialdevelopments are dealt with by the IJssel Delta project which aims at achieving asingle integrated spatial development plan (Hidding and Vlist 2009), acceptable to allstakeholders.Figure 1: Location of the IJssel Delta in the Netherlands1.3 Partners and stakeholders In 2004 the Province of Overijssel initiated the process of making a sustainabledevelopment plan for the IJssel Delta area. The Province has played a coordinatingrole in the planning process (Brink 2009). The development plan has been prepared inclose cooperation with other stakeholders: ministries, municipalities, neighbouringprovinces, water boards and many non-governmental organisations in the region. TheMunicipality of Kampen, the Water Board Groot Salland and the Province ofFlevoland have been the most important partners. The national Government alsocommitted itself to this project and selected the IJssel Delta project as a pilot projectfor modern integrated river flood management using the collaborative andparticipatory approach principle with a strong focus on spatial planning (VROM2010). The national ministries still involved are the Ministry of Infrastructure andEnvironment, and the Ministry of Economic Affairs, Agriculture and Innovation.Furthermore, the public (a.o. local farmers and inhabitants of Kampen) has beenactively involved in the plan-making process. 3
  • 4. 2. River flood management as a trigger for creating a river bypass2.1 Safety standards in flood protection The required safety standards for flood protection in the Netherlands areimposed by law. These safety standards are expressed in terms of water levelexceedance probability and are related to the design river discharge and to thecorresponding design water levels. The dikes are required to withstand these waterlevels (TAW 1998), (Anon 2009). The river IJssel is a downstream river branch of the river Rhine in theNetherlands. The design river discharge for the Rhine and its branches has anexceedance probability of 1/1,250 per year. The IJssel Delta area forms a transitionzone between the lake IJssel and the river IJssel. Due to its location the area isexposed to floods from the river IJssel and to storm-induced floods from the lakeIJssel. Therefore the safety standard of the area is set at 1/2,000 per year, with acorresponding design discharge of 2,550 m³/s. The maximum damage caused byflooding of the IJssel Delta is estimated at € 2 billion (Brinke et al. 2008), (Vermeulenand Leenders 2009).2.2 Climate change In 1993 and 1995 extremely high river levels occurred in the Netherlands, creatinga nearly-catastrophic situation. More than 100,000 people along the Rhine brancheshad to be evacuated. New research on the statistics of river discharges caused thedesign discharge in the river Rhine to be increased from 15,000 m3/s to 16,000 m3/s(V&W 2006). For the downstream stretch of the river IJssel (a Rhine branch), thiscaused an increase of the design water levels with 0.10 to 0.50 meters (Sokolewiczand Hoeven 2005), (V&W 2006). The existing dikes are not designed for these higherwater levels, therefore short-term measures are necessary to keep the safety againstflooding at the level required by the law. Considering the expected climate change as projected by IPCC (2007), an increaseof the design discharge of the Rhine to 18,000 m3/s and a sea level rise of 0.60 meterin 2100 are taken into account in the national policy in the Netherlands (V&W 2006).This would cause the design water levels in the downstream stretch of the river IJssel 4
  • 5. to rise with 0.20 to 0.60 meters (V&W 2006). Therefore, the climate change has to beconsidered in today’s plans for the long-term development.2.3 Room for the River The increased design discharge along the Dutch rivers requires measures tomaintain the required safety against flooding. Instead of building higher and strongerdikes a new strategy has been chosen in the Netherlands: to increase the conveyanceof the river system by creating more space for the flow. This strategy - a real‘paradigm shift’ in water management - has been adopted in the national Dutchprogramme ‘Room for the River’ (V&W 2006). Instead of a foe - that should betamed and conquered - water is becoming more and more a friend for the planners andwater managers. There is growing awareness among them that water and floodprotection measures create opportunities for spatial development, such as nature,recreation and housing. The primary goal of the Room for the River programme is restoring the safetyagainst flooding to the level required by law without raising the dikes. This means thatthe increased design discharge of 16,000 m³/s has to be conveyed through the riversystem without exceeding the old (pre-2001) design water levels. The secondary goalis improving the “spatial quality” along the rivers by increasing the diversity betweenthe Rhine branches, strengthening the open character of the riverine landscape, andnature development in the floodplains (V&W 2006). The program consists of a large number of measures in the river Rhine systemin the Netherlands: 40 measures for the short-term (Figure 2), to be completed by2015, and several long-term measures, to cope with the projected climate change(increase of extreme river discharge and sea level rise). One of the most importantlong-term measures in the downstream reach of the river IJssel is the so-called bypassKampen. The total budget available for the 40 short-term measures amounts to € 2.3billion. 5
  • 6. Figure 2: Overview of the short-term measures envisaged within the Room forthe River program2.4 Bypass Kampen Within the framework of the “Room for the River” programme, creating a bypasssouth of Kampen, as one of the options to increase the conveyance of the river IJssel,was considered to be a very promising and sustainable solution for flood managementin the delta of the river IJssel. A new river branch will be created, connecting the riverIJssel through the lake Dronten to the lake IJssel (see Figure 1).Figure 3. IJssel Delta during high river stage Constructing the bypass will add 350 hectares to the floodplains in the delta of theriver IJssel. This means breaking with the past, because for centuries space has been 6
  • 7. taken away from the river. For example, in 1850 the floodplains of the big rivers inthe Netherlands had almost 3 times more space (Demon and Alberts 2005) comparedwith the present situation. In case of an extremely high discharge in the river IJssel 25% of the flow will bediverted through the bypass to decrease the water level in the river IJssel below thedesign level, and a significant decrease of water levels along more than 10 km of theriver will be achieved. Even when the design discharge in the river Rhine is increasedin the future from 16,000 to 18,000 m³/s as a result of the expected climate change,the planned flood protection measures (especially the bypass) will keep the projectedwater levels along this 10 km long downstream stretch of the river IJssel sufficientlybelow design water levels to avoid large dike improvement works (Province Overijsel2011). The project has therefore a large contribution to the climate adaptation of thearea.3. Application of Modern Integrated Flood Management Approach3.1 Developments and spatial conflicts In the IJssel Delta project the combined opportunities for sustainable economicdevelopment and for enhancing the spatial quality of the area have been explored(Rooy 2009). In the coming decades, the inhabitants of the IJssel Delta area, south ofKampen, will experience significant spatial changes in their surroundings. Thesechanges and the resulting spatial conflicts are shown in Figure 4 and described indetail below.Figure 4: Illustration of developments and potential spatial conflicts in the IJsselDelta project A. The river IJssel: For the safety of the IJssel Delta area, the discharge capacityof the IJssel needs to be increased in the future. The expected increased design 7
  • 8. discharge cannot be conveyed within the present river profile. Therefore a bypass isneeded, with a capacity of about 700 m3/s. The bypass will provide safety againstflooding during extreme events with a probability of exceedance <1/500 per year. Incombination with other measures, the bypass should solve both the short-term andlong-term safety problems due to climate change. The preferred location for thisbypass is south of Kampen. B. The Hanze railway line: The first phase of construction of the Hanze line, arailway line from Amsterdam to Kampen and Zwolle (Figure 5), started in 2006.According to project planning, the railway line would be in operation in 2013. At thestart of the IJssel Delta project it became clear that only very minor changes in thealignment and the level of the railway would be possible. Major changes of therailway would lead to an – unacceptable – delay as the necessary review of therailway design would take too long. C. Expansion of Kampen: The municipality of Kampen has now 50,000inhabitants and covers an area of 162 km2, of which 27 km2 consists of water.Kampen is expected to expand considerably in the coming decades, with 4,000 housesto be built in the next 20 years. D. Spatial conflict: The above-described developments are to a certain extentconflicting, as they all claim parts of the same area. The combination andconcentration of the spatial challenges in the south-western part of the IJssel Deltawill contribute to the preservation of the north-eastern part of the delta, which is anarea with high cultural landscape values (National Heritage). Though some of thedevelopments are expected to take place on a longer term, extra synergy can beobtained between the developments by early master planning at this time. 8
  • 9. Figure 5: Hanze railway line under construction and N50 highway in the IJsselDelta3.2 Collaborative and adaptive process Preparation of an integrated spatial development plan as in the case of the IJsselDelta requires normally a long-lasting process involving many stakeholders. To obtainsufficiently wide support for the plan, often many iterations in the planning processare required. In the IJssel Delta project, being a pilot of modern river floodmanagement, a collaborative and participatory approach to the planning process (Kort2009) has been adopted. All relevant stakeholders (inhabitants and more than 20governmental and non-governmental organisations) have been involved already inearly stages of the planning process, and their concerns and requirements have beenthoroughly considered. This resulted in a relatively smooth plan development processwith only a minimum resistance to the plans, and in shortening the time span for theplanning and decision-making procedures. The planning process involved aparticipatory approach with many interactions between designers, experts andstakeholders, coordinated by the Province of Overijssel (Grijzen 2010). This process,started in 2004, comprised a number of distinct steps: Step 1: Exploration of possible bypass alternatives (2004). The relevant andtechnically feasible routes of the bypass south of Kampen were studied, and thesolutions that would fulfil the project requirements were elaborated. This resulted infive conceptual alternatives, spanning the range of possible solutions. 9
  • 10. Step 2: Public participation and consultation (2005). Inhabitants, entrepreneursand other stakeholders were invited to give their input for the alternatives (Figure 5).An additional (6th) bypass alternative was developed by the public and included infurther assessment and optimization. This alternative became an essential buildingblock for the preferred alternative and the Master plan (step 3 and 4).Figure 6: Public consultations Step 3: Decision making by the responsible authorities (2005). After publicconsultations, the responsible authorities, i.e. the involved municipalities, provinces,water boards and national ministries, have made their choice for a preferredalternative. Step 4: Further development of the preferred alternative (2005-2006). Thepreferred scenario was elaborated in more detail in advanced studies, and reviewed ontechnical, environmental, financial and legal feasibility. The most promising solutionswere selected. This involved regular feedback with administrators and representativestakeholders.Step 5: Adoption of the Master plan (2006). The Master plan was widely supportedby the public, as it was based on the 6th alternative of the bypass that was proposed bythe public (mostly farmers, assisted by planners and professionals). Step 6: Signing of the Covenant (2007). A binding agreement between the 11major stakeholders was signed in January 2007, with a commitment to work togethertowards implementation of the Master plan. Another 11 non-governmentalorganizations supported the plan. 10
  • 11. Step 7: Review of the regional and local land use plan (2008-2011), together witha Strategic Environmental (impact) Assessment (SEA) and an Environmental ImpactAssessment (EIA). In these impact assessments several design alternatives for theplan were studied, including a so-called most environmentally friendly alternative.This procedure has led to some adaptations of the Master plan. The current plan(Figure 7) resembles in almost every aspect the most environmentally friendlyalternative of the SEA. Step 8: Financial agreement and change of the scope of the IJssel Delta project(2009). In 2009 an agreement was reached to finance the project. The most importantcontributors to finance the total project’s cost of about € 325 million are the NationalGovernment and the Province of Overijssel. Part of the financial agreementconstitutes a change in the scope of the project: the IJssel Delta project will beimplemented in two phases and will be combined with another adjacent “Room forthe River”-project: the deepening of the river IJssel over a length of 22 kilometers.Combining the two projects enables a € 30 million cost reduction, as the sedimentdredged from the river can be used to construct the embankments of the river bypassas well as a mound (as part of a “climate proof dike”) for housing development. Oneof the most important reasons to modify the scope of the project was a recent changein policy of the National Government (see par. 4). Step 9: Preparation of the Detailed Design and Tender Documents. Recently, in-depth studies (a.o. hydraulic, morphological, geotechnical, environmentalassessments) have been completed. With the results of these studies, detailed designsfor the plan are being made. Tender documents are being prepared parallel to thedetailed design. An Engineering and Construct contract is foreseen in order to providespace for the Contractor for further optimisation. Studies, detailed design and tenderdocuments are to be completed in 2011. Step 10: Final decisions and agreements (2011-2012). In the coming periodseveral extra administrative decisions and agreements have to be obtained (e.g. landuse plan, project agreement, implementation agreement, many licenses and permits).The preparations for the decisions and agreements have already started. Step 11: Implementation. After obtaining the final decisions and agreements, theproject will be implemented in two phases: Phase 1: Construction of the physical part of the spatial development planconsisting of dikes along the bypass, new nature areas, sailing channel and locks for 11
  • 12. small boats. The dredged sediments from the IJssel will be used to construct the dikesalong the bypass. The bypass will not be connected to the river system yet. Theimplementation of Phase 1 is scheduled for the period 2013 - 2015. Phase 2: Construction of the inlet and outlet structures. Once these structures arein place, the bypass can be connected to the river and to the lake IJssel by opening theweirs during floods. The start of the implementation of Phase 2 is scheduled in 2021.Figure 7: Impression of IJssel Delta project4. Coping with changing policy The water level of the lake IJssel is controlled by large tidal flush gatesdischarging to the North Sea. According to the present government policy, the lake’slevel will not fully follow the sea level rise, and only a minor water level rise of 0.23meter in 100 years is foreseen in the coming century. This assumption was used as astarting point when drafting the IJssel Delta project. In 2007 the Government of the Netherlands requested an independent Committeeof State (the Delta Committee) to advise on flood protection in view of climatechange impacts in the Netherlands for the coming century (Delta Committee 2008).Two main Committee’s recommendations are of major importance for the IJsselDelta. The first one underlines the necessity to implement the long term “Room forthe River” measures – such as the river bypass – as soon as possible. The second oneis to gradually increase the level of the lake IJssel with a maximum of 1.5 meter in thelong term to cope with the increasing sea level and to provide a sufficient buffer of 12
  • 13. fresh water. These recommendations are expected to be incorporated in theGovernment’s policy, although it is not clear when and to what extent this will be thecase. A large increase of the water level in the lake will affect the IJssel Delta and thebypass. To cope with the possible change in the policy, a flexible approach isfollowed in the design of the projected dikes: they are designed to the current (lessstringent) policy requirements, but the design includes sufficient flexibility to be ableto raise the dikes in the future. A part of the new dike will be constructed as a climate-proof dike – a kind of unbreakable super dike – that can serve as an embankment forhousing development. As a no-regret measure, this climate-proof dike and all concretestructures are designed for the future (higher) water levels in the lake IJssel. As theimplementation of the large inlet and outlet structures in Phase 2 is postponed till2021, it will be possible to adapt their design to the decision of the NationalGovernment about the increase of the water level in the lake IJssel that is expected tobe taken in 2015.5. Lessons learnt1. The regional government (as a director of the plan-making process) has a crucial role to raise awareness for climate change and to gain public support for climate adaptation measures in the area. In the case of project IJssel Delta an intensive, bottom-up process of public participation has resulted in a new optional draft for the bypass (a 6th alternative) that was made by the public;2. To make sure that climate adaptation measures are taken seriously and are being implemented, a combination and integration with spatial planning and development is recommended (“think beyond the water box”). An illustrative example of this integrated approach is the combination of five spatial challenges – housing, infrastructure, nature development, leisure, agriculture – with a river bypass in the IJssel Delta project;3. Thinking beyond the water box requires that new coalitions have to be made (cooperation with other policy fields and levels, private investors and project developers). This requires a reflexive, collaborative style of planning in which communication between the stakeholders and joint fact finding are key elements (Healey 1997); 13
  • 14. 4. For this collaborative style of planning (which requires skills of facilitation, advocacy, networking and negotiation), also strong and visionary leadership are essential competences for the project leader and the responsible political representatives (for instance in cases of impasses between the stakeholders);5. The combination of water management with spatial planning has a potential to generate additional sources to finance climate adaptation measures. Several governmental bodies contribute to finance the IJssel Delta plan.6. Conclusion Creating a bypass to give the river more conveyance has been demonstrated to bea very promising solution to flood hazards in the project area. While reducing floodrisks, it also creates opportunities to enhance the environmental quality. Climate-proofing is a critical factor being taken into consideration in the project. Thechallenge for the coming decades is to harmonize future spatial planning with floodprotection and creating “room for the river”. The planning process followed in the IJssel Delta project required large flexibilityto adequately respond to the changing policies, climate change projections, interactionwith other projects. The project organisation was able to successfully introducenecessary changes to the plans, make no-regret decisions, introduce phasing in theimplementation program, achieve large cost-reduction by combining twoneighbouring projects, and secure additional funding sources through integrationbetween sectoral activities. The participatory and collaborative approach to spatial planning as applied in theIJssel Delta project, with the support of a multidisciplinary expert team has proven tobe a successful practice in modern river flood management (Hajer et al. 2010). TheDutch Government has selected the IJssel Delta project as a “best practice” (VROM2010).AcknowledgmentsThe authors wish to express their gratitude for the valuable comments andcontributions from Joost ter Hoeven, Guoping Zhang, Frank Dekker, Yvonne vanKruchten and Jan Oomen. 14
  • 15. ReferencesAnonymous, 2009. Water Act (in Dutch).Available from:www.waterwet.nlBrink, M. van de, 2009. Rijkswaterstaat on the Horns of a Dilemma. Dissertation.Radboud University, Nijmegen, the Netherlands.Brinke, W.B.M. ten, Bannink, B.A., and Ligtvoet, W., 2008. The evaluation of floodrisk policy in The Netherlands. Journal of Water Management, Volume 161, pp. 181-188.Delta Committee, 2008. Advice to the Dutch Cabinet.Available from:, A., and Alberts, F., 2005. Lange termijn visie Ruimte voor de Rivier (inDutch). Rijksinstituut voor Integraal Zoetwaterbeheer en Afvalwaterzuivering.Grijzen, J., 2010. Outsourcing Planning. What do Consultants do in Regional SpatialPlanning in the Netherlands. Dissertation. University of Amsterdam.Hajer, M., Grijzen, J., and Klooster, S. van ‘t, 2010. Strong Stories: How the Dutchare reinventing Spatial Planning. Design and Politics #3. Rotterdam: Uitgeverij 010.Healey, P., 1997. Collaborative Planning. Shaping Places in Fragmented Societies,2nd ed. Hampshire, England and New York, NY: Palgrave MacMillian.Hidding, M., and Vlist, M. van der, 2009. Ruimte en Water: Planningsperspectievenvoor de Nederlandse Delta (in Dutch). The Hague, the Netherlands.Hoeven J. ten, Louters, T., Sokolewicz, M.J., and Otten, A., 2007. Future of theIJsseldelta: an example of Contemporary River Basin Management and Adaptation toClimate Change. In: Proceedings of the 31st Annual Conference of Association ofState Floodplain Managers, June 2007, Norfolk, Virginia, USA.IPCC, 2007. Contribution of Working Groups I, II and III to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change; Core Writing Team,Pachauri, R.K. and Reisinger, A. (Eds.), IPCC, Geneva, Switzerland.Kort, A.T. de, 2009. Designing a Strategic Plan Development Approach forIntegrated Area Development Projects. Dissertation. University of Twente, Enschede, 15
  • 16. the Netherlands.Louters, T., Pierey , J., Ellen, T. van, and Otten, A., 2005. Future of the IJsseldelta:an example of Modern River Basin Management. In: Proceedings of the 2ndInternational Yellow River Forum, October 2005, Zhengzhou Shi: Yellow RiverConservancy Press.Otten, A. 2009. Climate adaptation in the IJsseldelta. In: Proceedings of the 5thWorld Water Forum, March 2009, Istanbul, Turkey.Province Overijssel, 2011. IJsseldelta Zuid, bypass Kampen, Hydraulica en Veiligheid(in Dutch).Rooy, P. van, 2009. Nederland Boven Water: Praktijkboek Gebiedsontwikkeling (inDutch). Habiforum/NIROV/VROM, Gouda/The Hague, the Netherlands.Sokolewicz, M.J., and Hoeven, J. ter, 2005. Hydraulische beschouwing bypass (inDutch), DHV.Available from:, 1998. Fundamentals on Water Defences. Technical Advisory Committee onWater Defences. Delft, the Netherlands.V&W, 2006. Spatial Planning Key Decision “Room for the River”. Ministry ofTransport, Public Works and Water Management, the Netherlands.Available from:www.ruimtevoorderivier.nlVermeulen, C.J.M., and Leenders, J.K., 2009. Veiligheidsaspecten van de bypassKampen (in Dutch), HKV.VROM, 2004. National Spatial Strategy (in Dutch). Ministry of Housing, SpatialPlanning and the Environment, The Hague, the Netherlands.Available from:, 2010. Nederland verandert!: 23 Gebiedsopgaven van Nationale Betekenis (inDutch). Ministry of Housing, Spatial Planning and the Environment, The Hague, theNetherlands. 16