The contribution of stakeholder engagement to cultural significance assessment: the case of values-based conservation management planning for the Ocean Swimming Pool, Portugal

Introduction Values-based approaches are among the best practices for management and conservation planning. However, cultural significance assessments (of the attributes and values of cultural heritage) have generally been performed by experts (top-down) instead of including expert and nonexpert communities (top-down and bottom-up). Objectives This paper presents a multitechnique approach in which different strategies are applied to assess the perceptions of cultural significance held by several actors (users, managers, staff, experts, children, students, virtual community) within the framework of the Keeping It Modern Grant awarded by the Getty Foundation (2020–2023) for the Ocean Swimming Pool (1960–1966) designed by Álvaro Siza in Matosinhos, Portugal. Method Interviews, surveys, social media analysis, and workshops with children, students, and experts were adopted for the method, and, whenever possible, the ‘Imagine Ballarat’ Love, Change and Imagine questions were utilised as a resourceful instrument for assessing the significance attributed by multiple stakeholders. Results Based on the results, stakeholders’ opinions and values regarding the heritage site could be compared, which revealed the relationship between the values and the groups of actors, thereby deepening the complexity of heritage sites as National Monuments. Conclusion By using this integrated perspective, we could define the cultural significance of a modern heritage site through an inclusive methodology while also establishing the grounds for conservation policies within a more broadly participative management of change.


Values-based approaches to conservation management planning
Values-based (or "values-led") approaches stand out among the most recommended processes for designing conservation management plans.According to UNESCO (2013, 24), 'the values-led approach is, in many ways, a response to the recognition of the increasing complexity of heritage' in the conservation practices of the final decades of the 20th century, enhancing conventional strategies exclusively focused on the conservation of materials while striving to integrate the associated social significance and meanings.Aligned with the Burra Charter process (ICOMOS Australia 2013), these approaches are currently advocated by institutional bodies such as the World Heritage Convention (UNESCO 2013) and the Getty Foundation (MacDonald 2022).
According to the Burra Charter (ICOMOS Australia 2013), cultural significance encompasses the values recognised by specific communities at a particular time, leading to their registration or statutory listing as heritage.Hence, identifying cultural significance through physically investigating places, researching archives, and consulting actors are all critical components of the management process for such sites and provide the first step for decision-making, specifically about what deserves preservation and what is susceptible to change.Hence, implementing cultural significance assessments reflects a crucial means of identifying exactly what attributes should be conserved and why (values), i.e., the reason(s) that justify their continuity for present and future generations (Tarrafa Silva and Pereira Roders 2012).
However, most cultural significance assessments and heritage listings have traditionally been produced by heritage-related experts, such as historians, archaeologists, architects, and art curators, reflecting their knowledge, disciplinary bias, and value systems (Smith and Waterton 2012).On the other hand, nonexpert communities introduce different levels of empathy to assets and create their own 'heritage lists' , although the values they identify, especially social values, are often overlooked in conventional heritage assessment processes (Wagenaar et al. 2023).While the resulting lists are likely to differ, they can still be complementary whenever they are equally addressed in subsequent planning policies.This lack of broader recognition has been identified as one of the causes of the artificial but traditional conflict between development and heritage conservation (Veldpaus 2015).
Hence, to ensure more sustainable and accountable decisions, assessing cultural significance must be a joint activity between experts and nonexpert communities, especially those still willing to use the assets in question.The information gathered from the engagement and vision of nonexperts, complemented by the outputs of a multidisciplinary expert group, might provide the key to a management and action plan that connects with a place, its people, and its identity (Court and Wijesuriya 2015).Despite international recommendations such as the Faro Convention (CoE 2005) or, most recently, the HUL Recommendation (UNESCO 2011), the effective integration of community engagement initiatives to inform urban management policies remains shallow and seldom applied to international and national contexts that are more significant than local-level projects (Bandarin and Van Oers 2014).

Ensuring stakeholder engagement in the values-based conservation management planning of modern heritage properties
According to the Burra Charter framework adopted by the Getty Foundation (Avrami et al. 2019), five stages structure a value-based conservation management plan: i) understanding the place, ii) assessing its significance, iii) assessing its condition, iv) planning conservation and management, and v) monitoring.Stages ii) and iii) are considered complementary stages for informing policy planning and conservation activities (Fig. 1).However, in keeping with their subjectiveness and transitory nature, identifying the values that embody cultural significance and incorporating them into meaningful practices (Havinga et al. 2020) represents a complex task for which interdisciplinary capacities from the conservation management field and coupled with the ability to combine different assessment methods are needed.Several conservation management plans that are available at the 'Keeping It Modern' Report Library (The Getty Foundation 2021) are, with rare exceptions, otherwise absent from the integration of participatory methods for assessing cultural significance.Thus, the research question is as follows: How can conservation management plans be carefully designed to incorporate and balance the prevailing diversity of values?
The growing incorporation of participation in planning heritage conservation projects (Rosetti et al. 2020) has emerged as an important topic of research for responding to this issue.Widely demanded, participation reflects one of the most common requirements in current regulatory frameworks for safeguarding culturally significant buildings.However, 'generic, interventional, and partnership are the most used forms of participation […] which is reflected in the emergence of theorisation about and widespread attempts to implement people-centred approaches in heritage processes' (Rossetti et al. 2022, 19).Furthermore, as participatory strategies are mostly applied to historic areas rather than to single buildings, as seen in the HUL pilots in Cuenca (Ecuador) and Ballarat (Australia) (Rey-Pérez et al. 2017;City of Ballarat 2016), the most commonly cited case studies do not actually discuss how theoretical and overarching functions may be adapted (Heras et al. 2019;Simakole et al. 2019).
This paper does not aim to exhaustively discuss the principles or practices of participation in light of the current state of the art; however, just as the values-based approach strives for better community involvement in developing management plans, it generates intersectional issues.Furthermore, within the framework of the responsibility to mediate unbiased perceptions of a heritage site, a practical means of quickly evaluating stakeholder identity bonds to cultural heritage and thereby providing planners with a simpler, more comparable and resourceful instrument for the assessment of significance by multiple stakeholders is lacking.In addition, in new heritage categories such as modern heritage, the assessment of cultural significance can be particularly effective because not only do those structures remain in use but also their construction is still part of social memories.Thus, stakeholder engagement can rapidly enhance the continuity of usage combined with the added value of maintaining authenticity and integrity in ways that might be difficult to achieve in the case of derelict buildings or assets from a more remote past.

Objectives
This article describes the cultural significance of the Ocean Swimming Pool (1960Pool ( -2021)), which resulted from a process of integrating the perspectives of a broader panoply of actors related to its construction, current management, and usage.Designed by the Pritzker Prize winner Álvaro Siza and built between 1961 and 1966 in Matosinhos, Portugal, this modern heritage in concrete has been listed as a National Monument since 2011 and included in the 2017 World Heritage Tentative List (Fig. 2).Engaging communities in a broad sense, specifically the 'communities of place' (users and visitors), 'communities of interest' (experts, builders), and 'communities of practice' (managers) (Court and Wijesuriya 2015), was a fundamental decision in the design process of the Ocean Swimming Pool Conservation Management Plan, which was drafted under the framework of the 'Keeping It Modern Grant' awarded by the Getty Foundation (2020-2023).As a public facility that is used continuously, mostly by local communities, these voices, along with those of experts, had to be incorporated into discussions about the future management of change.In addition, the involvement of communities also favours the establishment of a greater sense of identity and connection with the place through their engagement in different activities (Court and Wijesuriya 2015).
Thus, this paper aims to demonstrate how stakeholder engagement processes, adapting their approaches to each particular social group, are a crucial means of informing more comprehensive and inclusive heritage management policies.

Methods
Following the aforementioned perspective, the broadness of the methodology implemented, combining the perspectives of experts and governmental institutions with those of building actors, site managers, and nonexpert communities (e.g., users and visitors, including children), was a concern of this research.This multitechnique approach (Table 1) included i) interviews, ii) surveys, iii) social media analysis, iv) workshops, and v) other activities, which helped both to minimise potential gaps and to expand the representativeness of the research.
Three key questions (Fig. 3), which were adapted from the 'Imagine Ballarat' methodology (City of Ballarat 2013), established the grounds for designing the protocol applied to different stakeholders, inquiring about i)  what they love about the site (values and attributes), ii) what they would change (vulnerabilities) and iii) how they would imagine the site in the future (expectations and recommendations).Hereafter, these questions are collectively identified as LCI.One positive aspect of this method is its linkage of cultural significance to policy planning in a simple and efficient manner.However, in some groups, the adapted 'Imagine Ballarat' LCI questions were only partially applied, whether for the sake of clarity, time constraints, language or other surveying restrictions.In these cases, preference was attributed to the 'love' question, as a statement of significance inherently needs to be developed first for cultural significance assessments.

Interviews
Managing the Ocean Swimming Pool is a responsibility that is shared between the Municipal Council of Matosinhos and the municipally owned corporation Matosinhos Sport.The Municipal Council of Matosinhos is the owner and the principal stakeholder responsible for the maintenance of the Ocean Swimming Pool.Due to the organisational structure of this public institution, property maintenance is also undertaken by different municipal departments, such as the Municipal Council of Matosinhos' Municipal Buildings Division.During the bathing season (from June to September), Matosinhos Sport ensures that the daily maintenance routines of the Ocean Swimming Pool are followed and determines the regulations for usage.
Semistructured interview scripts (Fredella and Zecca 2020) were produced based on the planning and knowledge tools of Ballarat's HUL model, as mentioned; the strategy of the 'Ballarat Imagine Community Conversation' (City of Ballarat 2016) was adopted, and actors and management and maintenance representatives were brought together while this approach was adapted to an interview strategy.These interviews spanned the organisations responsible for maintaining the Ocean Swimming Pool.For the Municipal Council Departments, these interviews focused on the functions, difficulties, and policies of each department for the Ocean Swimming Pool.Additionally, they were directly asked all the adapted 'Imagine Ballarat' LCI questions.These interviews took place with the six heads of the Municipal Council Departments related to the site's general management (culture, heritage, planning, environment, civil protection and municipal buildings).These interviews were held during June 2021, individually and separately, with each department head questioned remotely through the Zoom online platform; the interviews lasted between 28 min and 2 h.
For the Matosinhos Sports staff, the interviews focused on each staff member's practice and daily routines in conjunction with the adapted 'Iimagine Ballarat' LCI questions.The interviews were conducted with all ten staff members (division head, technical coordinator, technical director, bar concessionaire, maintenance foreman, receptionist, lifeguard, security guard and cleaning assistant).These interviews were conducted in June 2021, individually and separately, with each staff member in the Ocean Swimming Pool building; the interviews with each member lasted between 14 and 55 min.
Although the number of people directly interviewed is low ( 16), the linkage of the managers and workers with the site facilitated the definition of several common ground points of interest and provided an important source for the development of future actions and policies regarding conservation management planning.Hence, this explains why the interviewees' responses also feature in the qualitative analysis in Sect. 3 of this paper.

Surveys
The local community and users were surveyed between June 2021 and July 2022, during the bathing season, and participants in the annual 'Open House' initiative in both years were also included (Fig. 4).Surveys that included all of the adapted 'Imagine Ballarat' LCI questions were distributed on site, either via a paper questionnaire or an online version using a QR code.The survey was applied in two different phases: a trial test with open-ended questions took place for a set of 20 respondents (June 2021), followed by a second survey (July 2021), which, based on the results of the first set, entailed multiple-choice questions (to assist the inquirer).
The survey protocol (Fig. 5) was set out to be as simple as possible not only to gather the maximum amount of information from respondents but also to generate different levels of empathy about the heritage site throughout the questionnaire (Sierra and Gómez, 2010).The questionnaire was divided into two parts: the first section focused on respondent data, and this was followed by the application of the adapted 'Imagine Ballarat LCI questions' .Then, the respondents' age, gender, schooling and nationality were determined through questions designed to frame the demographic data and assess the local community and user origins, family status and profession before the bond with the Ocean Swimming Pool was investigated.This included the classification of each respondent as a visitor, worker or tourist and, when a respondent was a frequent user, they were asked to share any interesting memories (open answer: 'when was the last time you visited the Ocean Swimming Pool?').Whenever respondents filled out the form with the help of an interviewer, as happened in some cases, this increased their willingness to collaborate and prepared the way for the application of the adapted 'Imagine Balarat' LCI questions.
The surveys of visitors and users included a total of 115 respondents belonging to the communities in a broad sense, namely, bathers (84%) and visitors or tourists (16%).Most respondents were Portuguese nationals (79%), aged between 25 and 34 years (27%) and between 35 and 44 years (20%).

Social media
Currently, virtual communities play a relevant role in assessments of cultural heritage and in definitions of policies and broader discussions about heritage sites.Hence, social media represents a powerful tool for generating dialogues between the most diverse actors, delivering data that communicate valuable aspects of different heritage sites through the experiences and memories expressed in these interactive community networks (Ginzarly et al. 2019, 1).Examining these platforms facilitates the identification of the landscape qualities spontaneously expressed by a community without directly relating their publication to heritage significance; in this way, values and attributes that might otherwise remain hidden can emerge (Ginzarly et al. 2019, 3-4).
The approach to social media spanned only the expansion of the sample for the first question (love) of the adapted 'Imagine Ballarat' LCI questions, enabling the integration of the general public perception following recourse to the social network Instagram.Using a search tool to identify and group photos with specific tags (#) related to the Ocean Swimming Pool, each facet of openaccess publications, namely, photographs, tags (#), and related comments, was coded to assess the values and attributes ascribed to the Ocean Swimming Pool (Dunkel 2015;Ginzarly et al. 2019;Pettinati et al. 2021).

Workshops
We utilised workshops to include responses to the adapted 'Imagine Ballarat' LCI questions from two different but equally important social groups: students and children.
The students' workshop was held within the context of a conference related to the conservation work carried out on the Ocean Swimming Pool.The conference took place remotely via the Zoom platform in April 2021 and lasted approximately two hours, with an audience of Architecture Master's Degree students at the Faculty of Architecture of the University of Porto.In total, 46 users were able to participate through the 'Poll Everywhere' platform, an online polling platform that creates a dynamic space to respond to open or multiple-choice questions, enhancing class discussions and presenting results in real time.
The conference activity consisted of the students openly discussing the adapted 'Imagine Ballarat' LCI questions in relation to the Ocean Swimming Pool.The students were asked to identify the three elements they loved the most about the Ocean Swimming Pool (attributes) and then to provide three reasons for why they should be protected (values).Answering these questions through the interactive polling platform allowed the final results to be displayed in real time through word clouds that revealed the most widely recognised attributes and values, which were later coded for integration with the results of other stakeholder engagement processes.
Regarding children as a social group, the Ocean Swimming Pool is visited by many children during the bathing season, whether in the context of leisure, sports, school, or other activities involving family and friends.Hence, children represent a public that should never be ignored when assessing cultural significance (Moniz et al. 2022;Carrascosa Moliner and Medina Lorente 2011).Children's engagement in assessing the attributes and values took place through on-site drawing activities during the 2021 bathing season.Hence, it was possible to interview twenty-four children aged between 5 and 13 years who visited the pools in summer activity groups, either with schools or accompanied by their families.In this case, we were only able to retrieve the 'love' question from the 'Imagine Ballarat' methodology from the drawing activity.Nevertheless, this allowed us to include a group that is normally overlooked but has an important and very direct unbiased perspective in this assessment of significance.

Other activities
Even if not specifically targeted at assessing significance, as in the case of the aforementioned participatory activities, numerous dissemination initiatives, such as dedicated exhibitions, guided visits, international symposiums, and publications, were implemented and have proven to be very important.These initiatives supported the research not only through raising public awareness and discussion about the Ocean Swimming Pool but also through collecting cross-references and peer confirmation.Within this overarching sense, the 'Sharing Memories' webinar (Cunha Ferreira 2022) must be mentioned due to its role both in disseminating the project and indirectly contributing to discussing the results set out in the items below.

Data analysis: coding techniques
The results of the participatory strategies were further analysed through a coding technique supported by the selected taxonomy of cultural values (Tarrafa Silva and Pereira Roders 2012).This framework of eight cultural values -social, economic, political, historic, aesthetic, scientific, age, and ecological -was used to identify and fairy compare all stakeholders.
In particular, in interviews with site managers and staff, quotations of key nucleons of their responses were selected, transcribed, and grouped for comparative analysis (Cunha Ferreira and Mendonça [eds.], in press, Annex C).Additionally, in surveys with user communities, in the first phase, we applied a precoding technique through interpreting the core sentences and words that collectively summarise the answers, an issue especially critical for the 'change' and 'imagine' questions.As these questions were not supported by a thesaurus, this technique proved useful in preventively establishing such a list.During the second phase of application, this not only enabled the survey to be taken by nonspecialists but also sped up the data analysis process.Moreover, in addition to following the precoding categories, there was a scope for identifying new topics (postcoding), so a broader range of information could be included.
The systematic nature of this content analysis methodology enabled further comparison in accordance with different data collection techniques and perspectives (Fusch et al. 2018) and the drafting of a statement of significance reflecting the aspiring inclusiveness of the approach (Spoormans 2023).

Assessing cultural significance through community perceptions
The results of the interviews with site managers, visitors and users are presented according to the following three questions adapted from the 'Imagine Ballarat' LCI questions, when applied: (1) the values and attributes recognised on the site (love), (2) the identification of site vulnerabilities (change), and (3) expectations concerning maintenance and conservation (imagine).

Site managers
The collated answers from the site manager interviews indicate that the aspects most valued by respondents (what they love) correspond to the site's 'integration into the landscape' (50%), 'everything' about the site (13%), and an equal percentage identifying the 'views over the sea' , 'modern architecture features' and the 'significance of the building in the collective memory' (9%).The respondents also identified issues related to the 'fabric of the building' and the 'diversity of users' (5%).In accordance with the aforementioned taxonomy of cultural values, the results demonstrate how the site managers identified predominantly aesthetic, ecological, and historic values in the Ocean Swimming Pool even if scientific and social values were also mentioned (Table 2).Among the aspects they would like to change, a large proportion of the respondents stated that 'no changes' to the building are necessary (40%), with specifying the 'need for more space for towels' (12%), 'accessibility improvements' (12%) and 'more safety measures for children' (12%) in second place.With lower percentages but among the aspects referenced by users were the need for 'more lighting in the changing rooms' , the 'bar being open for the whole year' , the 'construction of a restaurant according to the original design' and 'improved signage to facilitate access to the building' .
Finally, these respondents tended to 'imagine the building in the future' precisely 'as it is now' (72%), as a 'referential building of Matosinhos' (21%) and as having an 'increase of users' (7%).

Visitors and users
The survey results demonstrate how the attributes most valued by visitors and users (what they love) correspond to the site's 'integration into the landscape' (43%), the 'construction of swimming pools in harmony with the rocks' (14%) and 'modern architecture features' (10%).The respondents also identified several attributes related to the 'views over the sea' , the 'fabric of the building' (concrete, wood, and copper), the 'intense use by people of all ages' , the 'significance of the building in the collective memory' , the 'diversity of users' , the 'privacy of the building' and the 'recent conservation works' .The results of the aforementioned taxonomy of cultural values indicate that users and visitors were predominantly able to identify ecological, aesthetic, and historic values in the Ocean Swimming Pool even if social, scientific, and age values were also present (Table 3).
Among the aspects they would seek to change, a significant percentage of the respondents stated that the building needs 'no changes' (42%), and in second place, they specified the 'need for more space for towels' (12%), a 'reduction in the entrance fees' (10%) and 'more lighting in the changing rooms' (10%).With lower percentages but still addressed by users, there was a need for the 'bar to be open during the whole year' , the 'construction of a restaurant according to the original design' , 'improvements to accessibility' , 'signage improvements to facilitate access to the building' and 'more safety measures for children' .
Finally, these respondents tended to imagine the building in the future precisely 'as it is now' (59%), in 'good conservation condition' (14%), and 'operating throughout the whole year' (8%).Other aspects that the users imagined for the future were the site as a 'landmark reference of Matosinhos' , with the 'construction of a restaurant according to the original design' , 'more support infrastructure for visitors' , the 'increase of users' , the 'implementation of new technologies' and 'as a national monument' .

Virtual community
We first identified four relevant tags: #piscinadasmares (2,614 publications), #piscinadasmarés (824 publications), #piscinasdasmares (795 publications) and #piscinasdasmarés (205 publications).From these, we selected one hundred images published over nine years (02/13/2012-03/26/2021) for analysis.The retrieved data were systematised according to the date of publication, URL of the publication, type of profile, photograph, tags (#) and description of the photograph's content.Following the aforementioned taxonomy of cultural values, the attributes (tags) were translated to values, revealing that the virtual community predominantly identifies the Ocean Swimming Pool with aesthetic, ecological, social, historic and economic values (Fig. 6, Table 4).

Students
As illustrated in Fig. 7, the word cloud activity revealed that the swimming pool (piscina), the fabric (materialidade), the concrete (betão), pathways (percursos), and nature (natureza) were among the most commonly identified attributes.Unlike the other participatory activities, in addition to being asked what they love about the Ocean Swimming Pool, students had to identify reasons for protecting the identified attributes.Therefore, the transposition of the Tarrafa Silva and Pereira Roders (2012) taxonomy of cultural values was, in this case, specifically based on recognised values instead of attributes.Following the aforementioned taxonomy of cultural values, the results revealed that the students were predominantly able to identify aesthetic and social values in the Ocean Swimming Pool, even if they also recognised historic, political, ecological, and age values (Fig. 8, Table 5).

Children
The results here revealed a pattern related to the pool and its surroundings, highlighting their interrelationship.Extensive analysis of the activity results demonstrates how the children enjoy the natural elements, such as the water and the rocks, pointing to its 'integration into the landscape' (50%), the 'views over the sea' (24%), and the 'architecture' (10%) of the site by portraying the lines and geometry of the pool in their drawings.In addition, they often depicted their enjoyment of the pools in the company of friends and family engaging with the 'significance of the building in the collective memory' (16%).Therefore, we may deduce that the children highlighted the ecological, social, and aesthetic values of this activity as the main heritage values of the building (Table 6).
Table 4 Justification of the values identified by the virtual community (example of the coding process) (Source: CEAU-FAUP, 2023)

Comparing site manager, visitor, and user opinions
The definition of cultural significance corresponds to identifying and then further balancing the values and attributes identified by those deemed the actors on this heritage site.Hence, the resulting declaration of cultural significance designed for the Ocean Swimming Pool was supported by content analysis techniques applied to the interrelated documentation, on-site information, and outcomes of the various participatory strategies presented above.Identifying the attributes of a place ensures our capacity to recognise its significance while facilitating the planning and implementation of policies, actions and measures that support the maintenance of the values as defined by the different users.As a result, different measures may be established to adapt and develop an action plan that emphasises caring for the site's cultural significance.
As the opinions of the site managers, visitors and users fully embodied the 'Imagine Balarat' methodology through the application of all the LCI questions, we were able to perform graphic analysis of the responses by expressing the quantitative data addressing thematic answers developed by the precoding and postcoding techniques (Fig. 9).
(1) When comparing the results of the site manager interviews and those from the visitor and user surveys, there is relevant convergence between both groups regarding the identification of attributes (what they love) related to both the tangible -'the fabric of the building'-and the intangible dimensions, such as 'integration into the landscape' , 'modern architecture' , 'views over the sea' , and the 'diversity of users' .However, certain differences also emerged between these two groups, most likely due to the different natures of each relationship with the asset (the institutional/operational perspective of the site managers and the user perspective of the visitors).The site managers highlighted the 'significance of the building in the collective memory' , the 'swimming pool in harmony with the rocks' , the 'privacy of the building' , while the users and visitors solely recognised the 'conservation of the original design' .(2) Among the aspects they would prefer to change, both respondent groups agreed on the need for 'more space for towels' and the 'bar being open during the whole year' .Site managers highlighted the need for 'improvements to accessibility' , 'more safety measures for children' , 'the construction of the restaurant according to the original design' and 'signage improvements' , while users and visitors focused on the 'reduction of the entrance fees' and the need for 'more lighting in the changing rooms' .(3) Finally, both respondent groups tended to imagine the building in the future precisely 'as it is now' .Site managers saw it as a 'landmark reference of Matosinhos' with an 'increase in users' , while users and visitors imagined it in 'good conservation condition' , 'operational during the whole year' , 'the construction of the restaurant according to the original design' alongside 'more support infrastructures for visitors' , with the 'implementation of new technologies' and continuing to be a 'national monument' .

Relationships between values and groups of actors
According to this perspective, the inclusion of virtual communities, students, and children returns a broader interpretation of that expressed by site managers, visitors, and users.The social, aesthetic, and ecological values emerged as the most commonly referenced values identified by all the assessment groups in this paper.On the one hand, the identification of social values by both experts (site managers) and nonexpert communities contradicts the theory formulated by Wagenaar et al. (2023) as exclusive to nonexpert communities; on the other hand, the identification of aesthetic and historic values by the majority (except for the latter by the children's group) confirms the view that the values traditionally associated with the Authorised Heritage Discourse (Smith and Waterton 2012) are also encountered in perceptions of nonexperts.The consensus regarding ecological value, from site managers to the virtual community, along with social and aesthetic values, may be interrelated with experiencing the landscape and connecting with natural attributes.However, the declarations from the virtual community tend to be more abstract -due to their lack of daily experience (based on single visits) -and, correspondingly, relate more to 'common sense' , which is prone to reinforce the abovementioned justifications.This abstract dimension is somehow shared by the students who, in a similar fashion, are more attentive to design qualities and materials.
Scientific value was identified by site managers, users and visitors.The former probably mentioned this facet because they had a professional connection to the site and thus had greater concerns about the need to ensure that the building functions correctly.In conjunction with the social dimension, these values are embodied through their daily work and in recognition of the quality of the facility for embracing a diversity of users as well as the outstanding technical innovation for the time the building was built.The identification of these technological values by users and visitors, especially visitors, is probably interrelated with some of the surveys being implemented during an expert-organised visit (Open House).This strong influence from an expert perspective may also justify the exclusive identification of age values by the groups of users/visitors and the architecture students.Furthermore, users develop affectionate memories of family gatherings, events, and activities that enable the 'sense of place' and sustain the 'sense of time' .
Finally, economic and political values were each mentioned by only one group, the virtual community and students, respectively.The economic value generated by using the property is highly valuable to the broader community given the value placed on the opportunity to continue visiting and using the place according to its original function and format, which is also particularly appealing to tourists.Last, the exclusive identification of political value by students also arises from their bias and preknowledge related to work by the architect and awareness of his importance to the conference when they completed the survey.

Relationship between cultural significance and sustainable policy planning
The variety and broadness of the aspects raised around the Ocean Swimming Pool demonstrate the potential of stakeholder engagement for building more inclusive and democratic planning policies.Moreover, this research adopted a broad 'community' concept that extends beyond users and visitors to encompass the perspective of academics, staff, concessionaires, and the local municipal council.
The multitechnique approach for developing valuebased conservation management plans can facilitate a significant improvement in policy planning, as the statement of significance may serve to reframe policy criteria and ensure a better definition of future priorities for implementation.

Conclusion
Engaging with communities and stakeholders ranks among the best practices for heritage management and conservation, shifting from a top-down, reactive, and regulatory focused approach towards bottom-up, proactive, and participatory approaches.With this project, we tried to overcome the limitations of traditional approaches, which only consider citizen involvement in the final validation stages of conservation planning, by adopting an inclusive methodology.The consideration of these different voices, from lay communities to experts, produced a broader statement of cultural significance, enhancing the common awareness about the values and attributes to protect and preserve for future generations.
Nonetheless, this study still has the limitation of a small sample of participants, whether surveyed or interviewed, interrelated with the operational difficulties deriving from the COVID-19 pandemic restrictions, specifically regarding accessing the studied asset.Additionally, expanding the approach to other environments beyond those in this case study-e.g., neighbourhood or municipality residents, civic representatives, etcetera-may also introduce new perspectives and enrich the final statement of cultural significance.Finally, further research could benefit from introducing a second review of the values and attributes identified and thereby reducing the subjectivity always inherent to these assessments (Tarrafa Silva and Pereira Roders 2012).Furthermore, this research illustrates how experience justifies constantly reviewing the 'understanding the place' stage within the framework of developing a conservation management plan, demonstrating how the process of interacting with stakeholders deepened the rigour of conservation works.Other gains in the process may be identified across different levels, especially in terms of enhancing stakeholder capacity, building deeper public awareness about the asset's cultural significance alongside the relevance of their own values to this definition, and improving the education curricula of students and researchers, who gained the opportunity both to work with other perspectives and to recognise their own relevance to furthering heritage management strategies.In addition, the multiplicity of engagement techniques applied here may be extended to other techniques, enabling further definitions of the best recommended practices for addressing the diversity of the communities involved in heritage management processes.
Hence, by means of this positive process, this experience should be expanded to other activities in the future to continuously retain its significance over time and help managers in their daily conduct.

Table 2
Justification of the values identified by site managers

Table 5
Justification of the values identified by the students Artistic/cultural(Artístico-cultural)Aesthetic It represents the original product of creativity and imagination which might hold a creator's signature Symbolic (Simbólico) Political Exhibits the education role that heritage assets may play, using it for political targets Urban (Urbano) Ecological It represents harmony between the building and its environment (natural and artificial) Landscape (Paisagístico) Ecological It represents harmony between the building and its environment (natural and artificial)

Table 6
Justification of the values identified by children Table 8 details the correspondence between values and the policies developed in the Ocean Swimming Pool Conservation Management Plan (Cunha Ferreira and Mendonça [eds.], in press), also presenting how attention to community values can straighten conservation actions and management procedures.

Table 8
Correspondence between key heritage values and policy responses to sustain significance

of significance Cultural value Policy response to sustain significance
Outstanding work within the context of the revision of the ModernMovement Historic A.2 Álvaro Siza's design principles One of the most sought-after attractions in Matosinhos Economic C.5 Capacity and entrance control An exceptional case of an architect preserving his own work while enhancing its significance Significance and tolerance for change Is included in the Tentative List for World Heritage Status as a component property of 'Álvaro Siza' s Architecture Works in Portugal' and is listed as a National Monument