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Scoping river basin management issues with participatorymodelling: The Baixo Guadiana experience

Nuno Videira⁎, Paula Antunes, Rui SantosEcological Economics and Environmental Management Group, CENSE – Center for Environmental and Sustainability Research,Faculty of Sciences and Technology, New University of Lisbon, Portugal

A R T I C L E D A T A A B S T R A C T

Article history:Received 24 October 2006Received in revised form12 November 2008Accepted 12 November 2008Available online 16 December 2008

This paper details the design and implementation of a participatory modelling process inthe Baixo Guadiana River Basin, in Portugal. A group of stakeholders was involved in a causalmapping exercise that lead to the development of a shared view of the problems, pressuresand impacts characterizing the river basin. A simulation model was also developed tosupport experimentation with alternative management scenarios for the area. The paperlooks critically at the evaluation of the participatory modelling outcomes, both at theindividual and group levels, discussing the role of this approach in supporting the scopingstages of river basin planning and management processes. On the downside, the unstablegroup composition seems to have hindered the chances of producing a higher impact in thefunctioning of the group, and subsequently the capacity to sustain the level of collaborationrequired to achieve the strategic river basin objectives established during the participatorymodelling process. The paper discusses the issue of group stability as well as some optionsto overcome the limitations of unstable participant groups. The strengths of participatorymodelling, as underlined by the Baixo Guadiana experience, include the flexibility to adaptthe method to different contexts and participatory designs and the capacity to structure theactive involvement of stakeholders, providing an open and shared language forcollaborative policy design, fostering learning and knowledge integration.

© 2008 Elsevier B.V. All rights reserved.

Keywords:Participatory modellingRiver basin planning andmanagementWater Framework DirectiveBaixo GuadianaSystem dynamics

1. Introduction

With the emergence of new sustainable governance para-digms, participatory approaches to environmental decision-making have been brought to the fore of science, society andpolicy interfaces. The right to participate in environmentaldecisions is becoming more and more widespread in recentpolicy frameworks.

The European Union's water policy is currently shapedaround the Water Framework Directive (WFD) (Directive 2000/60/EC), which aims at the protection and improvement of all

Europeanwaters. TheWFD introduces an innovative approachto ecological and integrated water assessment, river basinplanning, elimination of pollution by dangerous substances,implementation of economic instruments and public partici-pation (Kallis and Butler, 2001). Lanz and Scheuer (2001)emphasize that the active involvement of the public andstakeholders is needed to leverage the success of the WFD.

While experiences with participatory methods have beenwidely documented (ComEC, 2002a; COSLA, 1998; Holmes andScoones, 2000; IAP2, 2002; Toth, 2001; van Asselt and Rijkens-Klomp, 2002; World Bank, 1996), there is still a relative lack of

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⁎ Corresponding author. ECOMAN – Ecological Economics and Environmental Management Centre, DCEA-FCT/New University of Lisbon,Quinta da Torre, 2829-516 Monte da Caparica, Portugal. Tel.: +351 2948300x10146; fax: +351 212948554.

E-mail addresses: nmvc@fct.unl.pt (N. Videira), mpa@fct.unl.pt (P. Antunes), rfs@fct.unl.pt (R. Santos).

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accumulated knowledge and guidance on the role of eachspecific combination ofmethods and processes inmeeting thechallenges set by the evolving context of participatoryenvironmental decision-making (Holmes and Scoones, 2000).

This paper describes and discusses results from a partici-patory modelling process that was conducted in Portugal, inthe lower part of the Guadiana River Basin known as “BaixoGuadiana”. The case study aimed at investigating the poten-tial of group modelling approaches for supporting the activeinvolvement of stakeholder groups in the scoping of riverbasin problems, pressures and impacts. The experience wasdeveloped as part of the ADVISOR research project (EU's EESD-RTD Program) that focused on the development and testing oftools for integrated planning and evaluation of river basininterventions, in the context of WFD implementation.

The following section presents some of the relevantchallenges posed to public participation in river basinprocesses, particularly in the European policy context. In thethird section the fundamental principles of the participatorymodelling methodology are presented. Section 4 describes indetail the Baixo Guadiana process, whereas section 5 focuseson the discussion of the lessons drawn from the case. The finalsection concludes with the key findings from the applicationof the method.

2. Public participation in integrated river basinmanagement

Sustainable water governance is hindered by the lack ofadequate water institutions, fragmented institutional struc-tures, upstream and downstream conflicting interests regard-ing rights and access to water, diversion of public resources forprivate gain and the unpredictability in the application oflaws, regulations and licensing practices, which affect mar-kets (WWAP, 2003). In a context of high complexity anduncertainty, participation is one of the emerging principles foreffective water governance, allowing for a shared responsi-bility in safeguarding water resources.

The rationale for participatory approaches is supported bythe recognition that environmental phenomena are complexand characterized by high scientific uncertainties, multipleinterrelationships, non-linear dynamics, large-scale conse-quences and irreversible damage (van den Hove, 2000).Participatory decision-making processes are urgent because,adding to the physical complexity, environmental problemsare characterized by conflicts between implicated actors,impacts spill over to many society sectors, responsibilitiesare diffused across scales and the distribution of benefits andcosts is uneven (Stave, 2002; van den Hove, 2000).

Recent discourses have been focusing on the goals thatmay be achieved through participatory platforms (Beirle andCayford, 2002; De Marchi and Ravetz, 2001; Holmes andScoones, 2000). For instance, De Marchi and Ravetz (2001)defended that participatory approaches contribute to achiev-ing three essential goals: widening the frame of policy issuesincluding all sectors of society, delivering a decision-makingstyle which is more responsive to democratic principles, andimproving the quality of decisions through the inclusion ofmultiple perspectives. Furthermore, these authors highlighted

that participation needs to be regarded as a complement,rather than a substitute for existing decision-making modes,recommending a context-specific approach to the use anddesign of participatory processes.

According to Article 14 of the WFD, the public (includingusers) has the right to be informed before and during theplanning process, the right to comment and the right to haveaccess to the background documentation and information onthe impending River Basin Management Plans (RBMP) (CEC,2000). Further than information and consultation, stake-holders and the general public are encouraged to be “activelyinvolved” throughout the whole WFD implementation cycle.The potential benefits for active public participation in thecontext of WFD implementation include: the possibility toobtain a better identification and consensus on the key watermanagement issues; the integration of knowledge, experienceand concerns of local communities in the RBMP; an increase incommitment toward action plans; the potential to reduceimplementation costs; and improved enforceability of bothregulatory and voluntary approaches (WWF, 2001).

Within the context of the WFD Common ImplementationStrategy (WFD-CIS)— a strategy agreed by the EuropeanWaterDirectors to address common challenges and promote coher-ent implementation among Member States — some broadguidelines on public and stakeholder involvement have beenprovided (ComEC, 2002a). However, additional research isneeded on the development and testing of the relevantparticipatory methods to apply at different stages of a riverbasin planning and management process.

In particular, at a scoping stage, the characterization of riverbasinproblems requires the reviewof environmental impactsofhuman activity in the area. This implies that river basinmanagers need to assess the pressures and impacts on awater body, thus assuring the identification of all potentiallyimportant problemswhichmay prevent the achievement of thegood ecological and chemical status set by the WFD. Further-more, in case thewater bodies lie in protected areas establishedunder Community legislation, such as theNatura 2000 sites, thereview of pressures and impacts also needs to considerbiodiversity andnature conservation standards (ComEC, 2002b).

The guidance provided by the WFD-CIS recommended theactive involvement of interested parties, as early as possible inthe scoping stages of the planning and evaluation process,where different perceptions and values can still be incorpo-rated in the identification of problems, goal setting and designof alternatives (ComEC, 2002b). Nevertheless, further guidanceis needed to support the design and implementation of theparticipatory platforms which are relevant for different riverbasin contexts. Thus, the ongoing experimentation withparticipatory processes and tools is expected to reinforcelearning about this issue.

3. Participatorymodelling platforms: facilitatingteam learning with system dynamics

System dynamics is a modelling methodology which has beenused for half a century as a framework to improve under-standing of the relationships between feedback structure anddynamic behaviour (Forrester, 1961; Richardson and Pugh,

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1981). Sterman (2000, p.107) defines structure as the combina-tion of “the feedback loops, stocks and flows, nonlinearitiesand delays created by the interaction of the physical andinstitutional structure of the systemwith the decision-makingprocesses of the agents acting within it". System dynamicsmodels are particularly useful at a strategic decision-makinglevel, supporting the analysis of the long term consequencesof alternative policies.

The applications of system dynamics are quite extensive,including corporate planning and policy design, public man-agement and policy, biological and medical modelling, theorydevelopment in social sciences, water resource management,dynamics of fisheries harvest patterns, interactions betweenwetland biodiversity and land use, and valuation of ecosystemservices, among many others (Boumans et al., 2002; Cavanaand Ford, 2004; Eppink et al., 2004; Low et al., 1999).

Integratedmodels of large systems require input fromawiderange of people and appropriate group modelling designs forbuilding consensus and mutual understanding about the waythe system works (Costanza and Ruth, 1998). This poses thequestion on how to structure the modelling process in order toincorporate the different knowledge sources and the percep-tions of contrasting individuals and groups (Vennix et al., 1992).Two participatory modelling approaches based on systemdynamics have been described in the literature: Group ModelBuilding (GMB) andMediatedModelling (MM). They sharemanymethodological elements, although there are some differencesin the design of the processes (cf. Videira et al., 2005).

GMB has been referenced for almost two decades as amethod for tackling messy problems, fostering consensus andcommitment through work in management teams. Itaddresses problem structuring in order to create concertedaction and has been extensively tested in the study oforganizational messy problems with client groups in privateand public institutions (Richardson and Anderson, 1995;Vennix, 1996, 1999). Although it was not originally a focus ofapplication, GMB experiences dealing with environmentalissues have been recently expanding (Stave, 2002, 2003).

MM has been developed since the mid 1990s and aims atfostering environmental consensus and collaborative teamlearning experiences (van den Belt et al., 1998). MM involvesbroad stakeholders groups in the construction of computer-based scoping models of complex problems, addressing theinterrelationships between ecological and economic issues(van den Belt, 2004). Scoping models have high-generality andlow-resolution and aim to increase the understanding of thedynamic behaviour patterns at play, rather than predictingprecise outcomes (van den Belt, 2004). These models areultimately used for policy analysis, allowing the comparisonand evaluation of different “simulation runs", which corre-spond to alternative “what-if?” scenarios.

In both approaches, a participatory modelling process typi-cally consists of a series of workshops where stakeholder groupscollaborate in the interactive and iterative development of asimulation model (Stave, 2002; van den Belt, 2004). A facilitatormakes use of system dynamics software (e.g. Stella, Vensim,Powersim) to conduct the model building process during theworkshops. InGMBprojects, otherkindsof systems thinking toolshave been extensively brought into play, such as qualitativemodels (Vennix, 1996). These consist of conceptual and diagram-

maticmodels, oftencalled “causal loopdiagrams",whichmapthemain variables characterizing a dynamic problem and the cause–effect relationships established between them. Although thesemodels may not be simulated or used to properly infer dynamicbehaviour, they may be particularly useful for scoping complexissues and reaching a better understanding of their underlyingfeedback loops (Coyle, 2000).

The participatory workshops cover a sequence of model-building stages, including problem definition, model concep-tualization, model specification and policy analysis (Vennix,1996; van den Belt, 2004). Each stage is usually developed in aseparate workshop, although there may be several adjust-ments to the process (van den Belt, 2004). Stave (2003)illustrated this flexibility by describing different GMB projectswhere the involvement of stakeholders in the modellingprocess only covered a subset of the model-building stages.

The length of each participatory modelling workshopdepends on a diversity of factors such as the number ofparticipants involved, the desired model detail and theproblem's level of complexity. For example, previous work-shops developed in Portugal varied from half a day to two full-day meetings (Videira et al., 2003). The desired number ofparticipants involved also varies significantly since pastexperiences have been conducted successfully with groupsof 5–10 participants (in small-group sessions), while othersregistered more than 40–70 people (in plenary sessions) (vanden Belt, 2004; Videira et al., 2003).

Apart from the modelling workshops, participatory model-ling involves preparatory activities (e.g. identifying andsetting-up the stakeholder group, conducting introductoryinterviews and preparing a preliminary model) and follow-uptasks (e.g. interviews or questionnaires, reports and modeltutorial) (Stave, 2002; van den Belt, 2004).

4. The participatory modelling process in theBaixo Guadiana

4.1. The case study area

The group modelling experience was developed in the BaixoGuadiana, which covers the estuarine section of the GuadianaRiver, in the Portuguese region of the Algarve (Fig. 1). Morespecifically, the workshops took place in the Natural Reserveof the Saltmarsh of CastroMarim and Vila Real de St.° António,hereafter referred to as “Natural Reserve", which was the firstarea to obtain such classification in Portugal (2089 ha desig-nated in 1975).

In this important humid area, it were also established aSpecial Protection Area under the EU Birds Directive, a Site ofCommunity Importance under the Habitats Directive (part ofthe European Natura 2000 Network), and a Humid Zone underthe Ramsar Convention. While relatively small, these pro-tected areas play an important role in the development of localactivities.

4.2. Designing the participatory modelling process

The participatory process was initiated by the Portugueseteam of the ADVISOR research project, who looked for advice

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and support from the national water and nature conservationinstitutes (INAG and ICN, respectively) in framing the issuesand setting up the workshops. However, there was no priorcommitment from private and public organizations to theimplementation of results from the participatory process.

The overall research objective was to develop and imple-ment a participatory modelling methodology to support thescoping stages of river basin planning and managementprocesses. More specifically, the Baixo Guadiana case studyaimed at:

• Developing a causal diagram depicting a shared view of thecurrent problems, pressures and impacts perceived by theparticipant group;

• Building up a simulationmodel based on the causal diagramto support the analysis of alternative developmentscenarios;

• Drafting a participatory action plan including objectives andmeasures for the sustainable management of the BaixoGuadiana river basin.

The overall participatory modelling methodology (Fig. 2)included two different types of activities — supporting tasksand modelling workshops — that will be detailed in thefollowing sections.

One of the concerns of the research team was to accountfor the quality of information and procedures used in theparticipatory modelling experience. To this extent, it wasdeveloped a specific Quality Assurance Protocol (CorralQuintana, 2000; Corral Quintana and Guimarães Pereira,2004), which guided the implementation and assessment ofthe research activities planned for the participatory exercise.This protocol accounted for different issues such as theframing of the process, social engagement, research group,research procedures undertaken, background informationand communication of information (Corral Quintana andGuimarães Pereira, 2004). Furthermore, it was used toincorporate quality of information concerns in the design ofthe workshops' scripts and in the final questionnairedistributed after the final session.

4.3. Preparatory activities

The preparation of the case study started 4months in advanceof the kick-off modelling workshop. The research team metwith representatives of the national water authority (INAG) todiscuss the selection of a representative site. At that stage, theGuadiana river basin emerged as an alternative since it wasthe pilot area appointed by the water authorities to test theWFD implementation in Portugal. Such choice implied notonly that the site was representative in terms of regional andclimatic conditions, ecosystem characteristics, diversity ofwater problems and user conflicts, but also that more datacould be available. Given the large extension of the Guadianariver basin and the available timeframe for developing theproject (9 months), the case study area was narrowed down tothe lower part of the Guadiana estuary.

The Natural Reserve provided a venue for the workshopsand agreed to serve as a local contact point for the researchteam, helping in the organization of the sessions and in theidentification of local actors. This steering group of research-ers and local managers met five times for setting up theprocess and performing the stakeholder analysis. The proce-dure involved press and literature reviews and group discus-sions to iterate the list of relevant social actors in the area. Theorganizers focused initially on the identification of a broad listof issues and then associated possible stakeholder groups tothose topics. The goal was to capture as much diversity inmental models or worldviews as possible. Ultimately, a listwith 86 stakeholders was produced and invitations were sentby post. The accompanying leaflet explaining the projectincluded a form to allow the suggestion of other participants.This cross-referencing procedure was used as a way toconsiderer possibly excluded groups and to validate thestakeholder list.

Given that only a minority of people returned the invite, inthe couple of weeks preceding the first workshop theorganizers contacted by phone practically all the 86 stake-holders, checking for their willingness to participate andtrying to set up individual interviews. It was possible toconduct 32 face-to-face interviews, using a common ques-tionnaire, which included open and closed questions addres-sing the issues of participation, perceived river basin problemsand opportunities that the interviewees wished to explore inthe future.

Fig. 1 –Location of the Baixo Guadiana case study area.

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Almost half of the interviewed group (44%) had notattended a participatory meeting before, whereas 28%revealed their past involvement in participatory modellingprojects, namely in the Ria Formosa Natural Park (van denBelt, 2004; Videira et al., 2003). With respect to representationissues, 94% commented that the list of invited stakeholderswas representative of the interested parties in the BaixoGuadiana, and therefore did not suggest the inclusion ofadditional participants.

The majority of the interviewees reckoned that thepromotion of a participatory process was very important.They said it was “positive to look at the Baixo Guadiana froman integrated perspective” and to “promote dialogue between

social actors that are not able to meet on a regular basis",therefore “preventing conflicts at the subsequent stages of theplanning andmanagement process". Regarding the difficultiesthat could arise in the process, they said “there are manyconflicts among participants", “people are not experienced inopen dialogue processes” and “people don't believe thatdecision-makers are willing to share power, thus participationmay turn out to be useless.”

Several sections of the questionnaire presented statementsto which participants indicated their level of agreement ordisagreement, on a scale from 1 (highly disagree) to 5 (highlyagree). Fig. 3 indicates that there existed, on average, a highlevel of agreement regarding the importance of participation

Fig. 2 –Stages of the participatory modelling process in the Baixo Guadiana.

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and modelling in river basin planning and management. Onthe other hand, regarding the two statements concerning theexistence of consensus among the group of participantsinvited to the Baixo Guadiana process, the most frequentanswers were “disagree” and “neither agree, nor disagree.”

Preliminary interviews were a useful tool for buildingrapportwith the stakeholders and explaining the participatoryprocess in more detail. These interviews allowed for collectingrelevant background information from the involved actorsand provided a point of departure for suggesting issues thatcould be addressed during the workshops. With this informa-tion, organizers prepared a workbook and distributed it to allparticipants attending the first meeting.

4.4. Firstworkshop: defining theproblemand conceptualizingthe qualitative model

Fifty-seven participants attended the kick-off workshop,which was scheduled for half a day. The group included 43representatives from 29 different organizations, and 14 own-ers of land parcels inside the Natural Reserve. The organiza-tions that were represented comprised the national waterauthority, two protected areas, local municipalities, regionaldevelopment associations, environmental associations, pro-ducers' associations, research institutes, tourism developers,and the regional directorates for the environment, agricultureand economics. This provided a good mix of decision-makers,technicians, scientists and local citizens. Nevertheless, somerelevant organizations did not send any representative to themeeting (e.g. domestic water supply firms and regionalSpanish administration).

The workshop started with a short presentation by theresearch team addressing the project objectives and metho-dology, the WFD and the role of stakeholder participation inwater planning and management. There was also the

opportunity for initial interventions from the audienceregarding the strategic importance of water in the BaixoGuadiana and the perceived level of consensus on currentriver basin problems and future visions.

Inaddressing these issues, one representative of the regionalenvironmental administration said that “arguably, waterreaches in the Baixo Guadiana its plentitude of functions; ithas a high ecological value here in the saltmarsh, providing anursery for many fish species, it is responsible for half of theAlgarve's domesticwater supply, it supports transportation andthe development of many human activities such as fisheries,agriculture, salt-making industry, tourismand recreation". “Thegreatest challenge inmanaging current conflicts betweenwaterusers",he continued, “is to reachacompromisebetweenhumanactivities and the preservation of the aquatic ecosystems". Amember of a Spanish environmental NGO added “onemay lookat the Guadiana withmarket eyes and simply sell its goods andservices, but there's also the viewpoint of the fish, birds andother specieswhoneed the river andwhose voices are not goingto be heard by the WFD (…) the management effectiveness ofthe Baixo Guadiana river basin is limited by the large number ofdams built upstream, both in the Portuguese and Spanish sides,whichaffect thewaterquantities arrivingat the southernpart ofthe basin (…) a riverwithoutwater is an oxymoron, but inmanysections, the Guadiana is water without a river".

Other participants intervened recognizing that the absenceof a broad consensus on current views and future visions for theBaixo Guadiana was a consequence of the fact that adequateinformationwasnot available toall the interestedparties. Therewas a strong discontent with “traditional” information andconsultation mechanisms, as these do not provide real oppor-tunities for sustaining better-informed decisions. They referredthat an effective level of participatory impact should be able topromote sharing of power and knowledge between those withvested interests in the Baixo Guadiana.

Fig. 3 –Selected results from the preliminary interviews.

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Most of the aired issues had already beenmentioned duringthe preliminary interviews. It was then time to structure thisinformation by means of the qualitative model. Picking up onthe momentum of the plenary discussion, the research teamproceeded to the task of conceptualizing the main problems,pressures and impacts perceived by the group. A piecemealprocedure was followed (Vennix, 1996) wherein the facilitatoruses flipcharts to write down the variables suggested by theaudience and then draws the causal relationships and thefeedback loops around them (Table 1).

The procedure was straightforward and participantsengaged in the model building process quite easily. Therewas no serious stalemate, an even in the cases whereparticipants had more or less conflicting viewpoints it waspossible to accommodate them in the model (Fig. 4). Forinstance, landowners expressed their vehement dissatisfac-tion with the fact that when the Natural Reserve was createdthey have lost their property rights without being compen-sated. Since then, most of their proposals for developing theland have been rejected by the Natural Reserve managers dueto the nature conservation status. When called to translatethis situation into the model, both parties agreed that thefundamental solution was to implement a land use plan forthe Natural Reserve, increasing the chances to achieve natureconservation goals and establishing, at the same time, clearand transparent land use rules for private users (Fig. 4).

Each sector of the diagram was recorded on separateflipcharts, which were put together at the end of the work-shop. There were several areas of intersection betweensectors, which challenged participants to think about theinterrelationships between the different problems. For exam-ple, the degradation and loss of protected habitats is affected bydecisions concerning: i) water abstractions and river fragmenta-tion upstream the Baixo Guadiana; ii) local recreation activities andnavigation; and iii) pollution resulting from wastewater emissions

and mass tourism activities. The balancing loops represented inthe diagram depict the feedback processes around thepressures, impacts and responses addressing the mainproblems identified by the group.

4.5. Secondworkshop: conceptualizing the simulationmodel

In-between workshops, invitations were sent again to allstakeholders. They were invited to work in two smallergroups, with the assignment to address the conceptualizationof a quantitative model, using the causal loop diagram of theprevious meeting as a point of departure. In each of thesmaller groups, the facilitator followed the script presented inTable 2.

Nine participants attended themorning session to work onthe conceptualization of the nature conservation sector. Therewere representatives from professional associations (salt-making and forests), Natural Reserve managers, a localtourism firm, the Regional Directorate for Economics andINAG. Landowners and local administration did not attend themeeting.

In the afternoon session, 18 participants were engaged inthe analysis of the model sectors related with water manage-ment and sustainable human activities. Adding to theorganizations represented in the morning session, partici-pants from the regional development associations, theregional environmental administration, the local administra-tion and two landowners were present.

The results from the workshop included a conceptualstock-and-flow model with a total of 91 variables distributedalong the 3 model sectors. The group also assisted in plottingthe historical behaviour patterns of the key variables in eachsector, over the selected reference timeframe of analysis(1970–2004).

4.6. Working between workshops: model specification

In between the second and the third meetings, the researchteam collected data to support the specification of the model.This task involved the analysis of several documents (e.g.scientific studies, policy documents) and other informationsources suggested by the participants during the secondworkshop. Two meetings were appointed with nature con-servation managers of the Natural Reserve for specificationpurposes. In these meetings, the research team organized around of discussions for quantifying the variables related withthe nature conservation indexes proposed during the secondworkshop. In other cases, participants were consulted bytelephone to provide information they had suggested.Researchers collected data from the Internet, public libraries,the National Institute for Statistics, INAG, and regionaladministration offices. Ultimately, it was possible to collectthe necessary information to construct a preliminary runningversion of the model to be used at the final workshop.

Modellers have checked the model for validation andsensitivity analysis purposes (cf. Barlas, 1996). All variableswere documented in the model indicating the sources ofinformation used and the assumptions made.

A third workbook was produced, explaining the modelstructure and how it was developed, presenting the elements

Table 1 – Script for developing causal loop diagrams

Task1.1

Considering one issue at a time (e.g. water management;nature conservation, sustainable human activities), ask forthe selection of a key variable (e.g. water quality) and place itat the centre of the flipchart.

Task1.2

Identify the possible causes of the problem as well as thepolarity of the causal relationships established betweenthese variables. For instance, a negative relationship mayarise between river flow regimes and irrigation. A negativelink indicates that the variables change in oppositedirections, i.e., all things remaining equal, an increase inintensive irrigation practices upstream the Baixo Guadianaleads to a decrease in river flows arriving to this area. On theother hand, a positive link indicates that two variableschange in the same direction (e.g. an increase in watersalinization leads to an increase in the degradation and lossof protected habitats).

Task1.3

The consequences of the problems are identified andexpressed as variables in the diagram.

Task1.4

Participants identify possible solutions to the problems.Facilitator moderates the discussion challenging theaudience to draw the feedback loops linking consequences(impacts) with the causes (pressures).

Task1.5

Assemble all the flipcharts in one piece, identifyinginteractions between different sectors to form a holistic viewof the problems of the Baixo Guadiana.

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of the first set of scenarios that could be run, based onsuggestions made throughout the participatory process, andindicating the preliminary strategic objectives and measuresdrafted in the previous workshop.

4.7. Third workshop: simulating the model and analysingpolicies with the stakeholder group

The final workshop gathered 20 participants, representingregional development associations, local administration,Natural Reserve managers, regional administration (econom-ics and fisheries), professional associations and tourism firms.The script for the policy analysis stage is presented in Table 3.

The stock-and-flow structure of the model was presentedside-by-side to its behaviour so that participants couldobserve one of the fundamental principles of the systemdynamics method — structure drives the patterns of beha-viour of the system. With the use of time-graphs and time-tables, it was possible to simulate model behaviour from 1970to 2004 (reference behaviourmode) and then from 2004 to 2015(scenarios' timeframe).

The scenarios, here understood as different policy experi-ments, were defined considering the drivers of change (e.g.

development projects, policy measures) that were alreadybeing planned, evaluated or implemented in the BaixoGuadiana river basin (Table 4).

The simulation of the scenarios and the analysis of theirimplications stimulated the group discussions. Some scenar-ios were particularly interesting since they allowed forcreating awareness about the trade-offs of a given interven-tion. This was the case of the wastewater treatment plantscenario. On one hand, this project would allow for reducingthe amount of pollution discharged in the river. On the otherhand, it would have a negative impact on the area'sbiodiversity, measured through a natural capital index.Following the Natural Capital Index Framework (RIVM, 2002),this variable was expressed in the model as the product of“ecosystem quantity” by “ecosystem quality". Since theconstruction of thewastewater treatment plantwould converta saltmarsh area inside the natural reserve, “ecosystemquantity” would decrease.

After experimenting with the scenarios, the participantscollaborated in the synthesis of the strategic objectives andmeasures for the Baixo Guadiana river basin (Table 5).Although the participatory action plan was only roughlydeveloped, the group agreed that this was a good vehicle for

Fig. 4 –Causal loop diagram of the Baixo Guadiana river basin issues.

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translating the lessons learned throughout the workshopsinto a broad set of policies for the future.

5. Discussion

This section presents the lessons learned from the BaixoGuadiana experience according to four analytical dimensions:the effectiveness of the participatory modelling process; thequality of information used; the impact that the experience

produced at the individual level and the effects in thefunctioning of the group. The observations collected duringthe workshops and the answers to the final questionnairesreturned by 11 participants support the analysis summarizedin Figs. 5 and 6. The values in-between brackets represent theaverage level of agreement to a given statement (scoresranging from 1 — highly disagree to 5 — highly agree) andthe percentage of participants answering positively to short“yes or no” questions.

As observed in Fig. 5, the participation rate— percentage ofparticipants attending each workshop in relation to the totalinvitations sent— decreased considerably from the first to theremaining workshops, which questions participants' satisfac-tion and reaction to the process. While some agents declaredto have overlapping professional commitments, the majoritydid not provide a justification, neitherwhen the research teamphoned before each workshop to try confirming attendance,nor at the end of the process through the evaluationquestionnaires. It turned out to be very difficult to getfeedback from the participants who left the Baixo Guadianaprocess; nevertheless it is worth exploring some hypothesesconcerning the causes and consequences of the negativeparticipation trend.

First, it may be argued that some stakeholders did notreturn after the first workshop because they were eitherdissatisfied with the process or their principal motivation wasnot in scoping the river basin issues. This seems to have beenthe case with the landowners group who revealed during thepreliminary interviews a greater interest in using the oppor-tunity as a way to proclaim the property rights dispute withthe Natural Reserve managers. Second, when participants arevolunteers it may be more difficult to compromise profes-sional obligations and support the travel costs to attend themeetings. This is particularly relevant in the cases wherestakeholders live and work far from the meetings venue,which was the case for some participants in the BaixoGuadiana process. Offering monetary compensation and/orscheduling the sessions after working hours could havehelped in overcoming these limitations. Finally, participantscould have been more loosely bound since they knew thatdecision-makers were not as committed as they would havebeen in case they were the promoters of the initiative,

Table 3 – Script for the third workshop

Task3.1

Distribute the third workbook.

Task3.2

Synthesize results from the participatory modelling process,followed by plenary group discussion.

Task3.3

Present the quantitative model, explaining the changesmade during the model specification stage; show theinformation sources for each variable; discuss theunderlying assumptions and possible ways to improve themodel and the quality of information supporting it.

Task3.4

Present and simulate different scenarios. Discuss thebehaviour-over-time graphs with the participants.

Task3.5

Review the list of strategic objectives and measures foreseenby the group to support integrated and participatorymanagement of the Baixo Guadiana.

Task3.6

Present the follow-up activities including the questionnairefor the evaluation of outcomes.

Table 2 – Script for the second workshop

Task2.1

Distribute the second workbook.

Task2.2

Recall project objectives and methodology; present thespecific goals for the workshop.

Task2.3

Debrief the results from the previous workshop, namely thecausal loop diagram including problems, causes, effects andintervention points.

Task2.4

Draft reference behaviour modes with the group: a) Selectthe dynamic variables associated with each problem; b)define time horizon—How far in the future? How far back in thepast lie the roots of the problem? c) Identify reference modes —What is the historical behaviour of the selected key variables andconcepts? What might be their behaviour in the future?

Task2.5

List the suggested information sources for quantifying thevariables; plan with participants the data collection process.

Task2.6

Ask for potential policies to address the problems— this willhelp to draft alternative management policies to integrate inthe simulation scenarios.

Task2.7

Present the system dynamics quantitative modellingmethodology and its building blocks: stocks, flows andauxiliary variables. Provide examples of stock-and-flowdynamics. Distinguish between material and informationflows.

Task2.8

Formulate the dynamic hypothesis by developing stock-and-flow maps of the causal structure with the collaboration ofthe group; the computer screen is used to project the modelonto a screen for all participants to follow and suggestvariables and linkages, with the help of system dynamicssoftware (e.g. Powersim, STELLA).

Task2.9

End session by debriefing the results that were achieved andpresent the objectives for the next workshop.

Table 4 – Scenarios studied with the Baixo Guadianasimulation model

Approval of the proposal for the construction of a wastewatertreatment plant inside the Natural ReserveInvestments in wastewater treatment efficiencyRegulation of flow regimes according to the Alqueva projectupstream in the Guadiana river basinDecreasing upstream water abstraction (e.g. for irrigation, urbansupply)Restoring the natural values of the Taborda and Venta Moínhossaltmarshes in the Natural ReserveRecovering traditional salt-making in the Natural ReserveLicensing of new fish farming industries operating inside the NaturalReserveLicensing of new golf courses in the Natural Reserve

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particularly since INAG was only a consultative partner andthe process did not report directly to a river basin authority.

While the size of the group and the mix of stakeholdergroups attending the second and third meetings were stillsatisfactory from the methodological viewpoint (see van denBelt, 2004 and Vennix, 1996 for in-depth discussion on theoptimum size for group modelling workshops), it seems thatthe participation rate affected some of the outcomes at thegroup level, as it is discussed below.

One of the risks of an unstable group composition is loosingmodelling focus and “group process memory". In the BaixoGuadiana experience, delivering workbooks, which included asynthesis of the results from the previous meetings helped toovercome this limitation. Moreover, the conceptualizationexercise developed in the first workshop was extremelyvaluable in providing a blueprint for the remaining model-building stages, focusing participants on the issues agreed bythe larger audience.

For the core group who collaborated until the end there arepositive indications regarding the potential of participatorymodelling in supporting river basin management processes.

They have agreed that the workshops were open, transparent,and fair in providing opportunities for each agent to contributeto the models. Also, according to their perspective, thesequence of events was effective and the model buildingstages helped in structuring the discussions. The majorityagreed that relevant management alternatives were gener-ated and strategic objectives were synthesized. They addedthat the most positive aspects of the process were “theinnovative and integrative character of the method", “theinteraction and possibility of dialogue between the agents”and “the construction of a shared vision of the problems".

Some sections of the Quality Assurance Protocol developedfor the Baixo Guadiana were included in the questionnaire toevaluate the perceptions of the participants regarding thequality of information used. As depicted in Fig. 5, there arepositive outcomes concerning the acceptance of the researchteam's legitimacy and competence, the documentation of themodels' information sources and the efforts in using completeand balanced information for the audience in question.Moreover, when asked to comment on the models' quality,i.e. its fitness for purpose, most answers pointed that they

Table 5 – Synthesis of the strategic objectives and proposed actions, associated with each of the Baixo Guadiana model'ssectors

Model sectors Strategic objectives Proposed actions

Sector 1: Natureconservation

Conservation of protected habitats and species Develop and implement the Land Use plan for the NaturalReserve

Promotion of partnerships and environmental education oflocal populations

Create an association of landownersContinuous information and training of landownersInstitutionalize dialogue between partners

Reversing population decline and immigration Promote activities and jobs compatible with natureconservation

Balancing nature conservation with economic developmentand the welfare of local populations

Promote integrated planning processesEstimate carrying capacitiesAssess the existing capacity of ecosystems for supportingdifferent types of tourism

Sector 2: Watermanagement

Promote integrated river basin management Modify flow regimesGuarantee ecological flowsSupport negotiations between water usesCreate a permanent organization for the integratedmanagement of the river basin

Maintain good water quality Provide mechanisms for adequate treatment ofwastewaterPromote good agriculture practices upstream, especiallywith respect to intensive irrigation

Guarantee navigation in the Guadiana river Develop long-term plan for sand extraction and dredgingSector 3: Sustainablehuman activities

Promotion of traditional activities Develop traditional activities (e.g. handicraft)Create certification schemes for regional products (e.g.olives, cheese)Support biological agricultureSupport salt products and traditional saltDevelop extensive fish farming

Promotion of quality tourism Develop tourism in the rural environmentLink tourism with sports activitiesLink tourism with traditional activitiesDevelop eco-tourismProfessional training and certification of traditionalfishing methods

Protect historical and cultural heritage Maintain cultural infrastructuresRestore traditional buildings with an historical andcultural value

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were relevant given the objectives established by the researchproject. On the downside, it was found that communication ofuncertainties could be significantly improved, as the processdid not cater for an extensive discussion of knowledge andinformation gaps.

Building on some of the criteria proposed by Rouwette et al.(2002) for measuring the effectiveness of groupmodel buildingprocesses, Fig. 6 presents the outcomes of the Baixo Guadianacase at the individual and group levels.

The overall distribution of scores indicates that the impactsat the personal level were greater than the effects in thefunctioning of the stakeholder group. The interactions andtrust between the group members were not significantlystrengthened as the process unfolded, which may arguablyowe to the changing group composition pattern discussedabove. Even so,many agents agreed that, from end-to-end, theprocess managed to include the perspectives of the mainstakeholders in the river basin. In addition, there weremedium to high impacts in the development of sharedviews/actions (consensus) and in the understanding of otherparticipants (shared language).

Regarding the personal evaluation of the group modellingintervention, the reactions were very positive. Stakeholdersrevealed that the workshops were worth their time, theywould recommend themethod to others and participate againin such type of process. The experience was also successful ingenerating insights and facilitating learning about the river

basin issues. Participants have commented that they learned“about a new method to structure interventions” and “aboutthe complexity of the problems in the Baixo Guadiana.”Although their perception of the key issues has not changedsignificantly, participants also revealed that the modellingprocess has increased their capacity to interrelate andintegrate those issues. In terms of ownership, the answersindicate that the sense of contributing to the overall results ofthe project was higher than the perceived contribution to thequantitative model. This observation is closely linked to thedesign of the process, since the model specification step wasperformed behind the scenes, in-between the second andthird workshop. In other experiments where stakeholderswere more deeply involved in model formulation the differ-ence between those two measures of ownership were smaller(Videira et al., 2003, 2005). Another positive outcome at theindividual level was the high level of commitment thatstakeholders declared towards the use of the process results.

6. Conclusions

Public participation is crucial for sustainable governance ofwater resources. In order to pass beyond the rhetoric ofparticipation, experimentation with emerging methods andtools is needed to bridge the gaps between the generalrequirements of the legal frameworks demanding active

Fig. 5 –Outcomes concerning the process and the information used.

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public involvement and the specificities of local contextswhere participatory processes unfold.

Building on the mediated modelling and group modelbuilding approaches, this paper describes the developmentand application of a participatory modelling methodology toscope the problems, pressures and impacts perceived by astakeholder group in the Baixo Guadiana river basin inPortugal. The outputs of the process included a qualitativemodel — causal loop diagram — that integrated the perspec-tives of 57 stakeholders about the Baixo Guadina river basinproblems, pressures and impacts. Using this conceptualmodel as a point of departure, a smaller group of around 20participants has attended two more workshops to collaboratein the development of a computer simulation model used forexperimentation of alternative management scenarios. Thelessons from the modelling workshops supported the defini-tion of strategic objectives and measures proposed by thegroup for an integrated management of the river basin.

The experience revealed that the main strengths ofparticipatory modelling in supporting the scoping of riverbasin issues lie in its: i) flexibility, ii) potential for structuringactive involvement of stakeholders, iii) capacity to offer anopen and shared language for collaborative policy design, andiv) potential for fostering learning and knowledge integration.

The method is flexible in the application to a variety ofsubjects and participatory contexts. Flexibility is also possiblein the procedure itself. As detailed in this paper, themodelling

team may prepare different scripts for knowledge elicitationtasks, which the process facilitator employs at critical stages.The case study also revealed the potential of using qualitativemodelling at the early stages of river basin characterization.This seems to be particularly useful when working with largestakeholder groups and/or in cases where participants havelimited availability to engage in a quantitative model buildingprocess. Qualitative modelling worked very well in thedevelopment of an integrated view of river basin issues,supporting the scoping of problems, pressures and impactsperceived by the group attending the first workshop.

In participatorymodelling, the stages of themodel buildingmethod are integrated in a broader participatory process ofreflection on the river basin issues. A logic and pre-definedsequence of tasks shapes the backbone of the agenda for themodelling workshops. The model building process encour-aged the Baixo Guadiana participants to focus on the leverageparameters affecting decisions, and constituted the leadingthread for discussions. This has shifted attention away fromrigid points of view and invited actors to present theirknowledge in a constructive and open manner. Moreover, asdefended also by Stave (2002), such a collaborative modellingprocess levels the playing field during the evaluation of policyscenarios. It does so by allowing all participants to proposealternatives and then focus on the analysis of its conse-quences over time and across different model sectors. Theprocess of supplying and communicating quantitative

Fig. 6 –Outcomes concerning the impact at the individual and group levels.

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information in a participatory modelling process is oftenpointed as a methodological limitation. In the Baixo Guadianacase this was tackled through the application of a QualityAssurance Protocol, which proved to be an essential tool forbringing quality assurance issues to the fore of the processdesign, implementation and evaluation stages.

One premise of participation lies is the assumption that theintegration of plural perspectives may lead to better decisionsby creating a holistic view in a team (Vennix, 1996). In theBaixo Guadiana, the modelling process helped in storing,structuring and transferring the vast amount of ideas, knowl-edge and opinions ventilated in the meetings. The evaluationof outcomes at the individual level showed positive resultswith respect to the reaction to the process, ownership,commitment and insights. At the group level, communicationand consensus on the issues seemed to improve, although theoutcomes were diminished by the decreasing rate of partici-pation from the first to the following workshops.

The issue of representation, more specifically the difficultyin maintaining a group perceived as representative through-out the sequence of workshops, has been one of the majorweaknesses of the experience. It called the attention for thedifficulties in monitoring and evaluating participants' satis-faction and engagement in voluntary processes. The resultsalso support the idea that quantitativemodelling is less suitedfor participatory processes where there are strong time,information and human resource constraints. The approachdemands an experienced modelling team, intensive datacollection, and a continuous effort to get in touch with andget feedback from the participants, from the preparatoryinterviews to the follow-up activities.

Finally, further research is needed on the development ofstrategies for mobilizing and sustaining collective action basedon the lessons learned from the participatory model-buildingprocess. This calls for the establishment of monitoring and ex-post evaluation protocols to measure the system changes andthe outcomes of the process at the organizational level.

Acknowledgements

The authors would like to acknowledge the support of theNational Water Institute and the Natural Reserve of theSaltmarsh of Castro Marim and Vila Real de St.° António. Theyare particularly appreciative of the support provided by DanielBorrego, Isabel Pires and Anabela Resende. Furthermore, theywould like to thank the collaboration of Serafin Corral Quintanaand Ângela Guimarães Pereira in the development and applica-tion of the specific Quality Assurance Protocol. The support ofthe European Commission to the ADVISOR project (EVK1-CT-2000-000074) is also gratefully acknowledged.

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