Alternatives to the “plaza dura”. Fostering urban biodiversity and citizen empowerment

Il·lustració © Raquel Marín

In terms of urban design, a “plaza dura” is deemed to be a solution for the urban planning of a public space with a large surface area, generally made of granite or concrete, with hardly any vegetation and limited street furniture. It has always been a source of controversy because it is an example of one of the many divides between the technical criteria endorsed by architects and urban planners and the public’s wishes.

The quintessential example on which the model of “plaza dura”[1] was built is the Plaça dels Països Catalans in Barcelona – work of the architects Albert Viaplana and Helio Piñón, with the collaboration of Enric Miralles –, a symbol of the new urban planning that put the Catalan capital on the world map in the 1980s. In 1984, it earned the FAD Award for Architecture and, in 2019, Barcelona City Council designated it the status of cultural heritage asset that hence merits special protection.

The square constitutes an area of ​​more than two hectares in size and is devoid of any landscaped areas, partly since it was built on an enormous set of railway tracks. Its original design includes two roofs. The one in the centre, which is taller, does not provide shelter from the elements due to its great slenderness and its transparent roof. The other, which is undulating and lower in height, traverses the square linearly and, although it has only limited street furniture (less than a dozen benches with integrated tables), its intention is rather to protect the flow of passengers heading to the train station. Despite the fact that the square constitutes the entrance to the Estació Sants train station, which has received more than 10,000 daily passengers for decades, the moderate provision of benches in the original design was completed with about thirty benches. They form a meandering line, with no shelter from the sun or the rain and, oddly, located on the square’s periphery, very close to the surrounding arterial road with the most traffic, Carrer de Viriat.

[1] Hard-surfaced square devoid of vegetation.

The “plaza dura” and the Barcelona model

The “plaza dura” emerged in a historical, political and economic context that should be borne in mind in order to understand the merits it pursued. In 1979, with a newly established democracy, the PSC (Partit dels Socialistes de Catalunya [Socialists’ Party of Catalonia]), in alliance with the PSUC (Partit Socialista Unificat de Catalunya [Unified Socialist Party of Catalonia]), came to power in Barcelona City Council. The 1980s were characterised by a significant shortage of resources, the beginning of the Olympic dream, which ended up coming to fruition in 1992, and a powerful community movement that on many occasions failed to reach an understanding with the City Council. In 1980, the architect Oriol Bohigas joined the Urban Planning Delegation. His decision as to how to regenerate Barcelona entailed a strong commitment to the construction of public spaces limited in size and in multiple neighbourhoods. He got rid of the cars from Plaça Reial, demolished a block in the Raval neighbourhood and gave impetus to squares in the Sants and Gràcia neighbourhoods. Compared to other municipal management models that endorsed a General Plan, such as Madrid, or a focus on investment in paradigmatic streets and in singular features, this urban planning scattered throughout the territory also meant that the budget for each of these squares was limited.

Besides the political and economic conditions, the “plaza dura” is part of a conceptual environment to whose construction Ignasi de Solà-Morales made a unique contribution, in whose writings we better understand the design agenda implicit in this type of solutions. In the chapter “Lugar: permanencia o producción” [Place: Permanence or Production] of his book Diferencias. Topografía de la Arquitectura Contemporánea [Differences. Topographies of Contemporary Architecture], he was opposed to a static and sacred concept of place and replaced it with the ideas of flow, dynamics, set of events and meeting point of energies. Furthermore, Solà-Morales argued that what he called terrain vague – semi-abandoned spaces with no functional definition – were the true essence of the urban, insofar as they provided an anonymous freedom that the citizen could exercise without the capitalist determination of the rest of the city’s spaces, which dictated what to do in each place also as an act of imposition of consumption.

The strong criticism of the so-called Barcelona model, in whose synthesis and structuring Oriol Bohigas played a leading role (he is credited with having had as much decision-making power as Hausmann in Paris or Otto Wagner in Vienna), is also applicable to the “plaza dura”. Josep Maria Montaner underlines the lack of dialogue with community movements, the very limited protection and appreciation for historic heritage (for example, the demolition of four Elies Rogent warehouses, considered the cradle of modernism to open the Ronda Litoral ring road, and Bohigas himself has said on several occasions that the best fate for the Sagrada Familia would be to become a Renfe train stop) and the lack of integration of sustainability criteria. To this list, from a present-day perspective, other criticisms can be added such as the zero integration of a gender perspective or the failure to contribute to a vision of placemaking where there is true observation, attention to and integration of the needs and desires of the users of the spaces.

To delve deeper into the gap between architects and society, the “plaza dura” and the example of the Plaça dels Països Catalans could be case studies of huge value. José Mansilla, urban anthropologist and member of the Observatory for the Anthropology of Urban Conflict (OACU), carried out a study in 2017 within the subject of Introduction to the Sociology and Psychology of Tourism through a brief exercise in participant observation with users. Most of those who took part in the study did not think of the place as a square; the perception was one of an ugly, dirty space, one for passing through and of little use. When asked which elements they would add to the square, they answered that they would add colour, afford it more green areas that would allow passers-by to take a breath; benches and collective rest areas to limit individual facilities that hinder conversation; and, finally, the installation of children’s areas, areas for dogs and an area demarcated exclusively for skaters. In a broader context, the participants called for the easing of traffic by reducing the presence of vehicles in general and connecting the area with the nearby thoroughfare Avinguda de Roma.

Il·lustració © Raquel Marín © Raquel Marín

Two years after this study, experts classified the square as cultural heritage and, therefore, its conservation in a state as close as possible to the original could have been imposed. It is one of the many signs of the divides between technical criteria and the public’s wishes. Where some see an example of architectural heritage that must be preserved for future generations, others fail to recognise a square or a place of minimum comfort. It seems, however, that the administrations and the RCR architectural studio, commissioned with a project to reform the square, are beginning to afford attention to citizen experience. The studio has announced that it will incorporate measures to alleviate traffic and will put forward a stronger presence of vegetation.

All this has not prevented the “plaza dura” from being a resounding model of success that continues to be replicated in many urban locations that are not built on sets of tracks and where the landscaping is perfectly simple. Only in Madrid, the squares of Callao, Ópera, Puerta del Sol, Tirso de Molina, Lavapiés, Santo Domingo, Pedro Zerolo, Chueca and de los Cubos follow this model. The reactions of outrage among citizens have been widespread and, in some cities, such as Seville, especially strong. The journalist Carlos Colón wrote for the Diario de Sevilla in 2016: “The Armas and Santa Justa hard squares were designed to piss citizens off, to disorientate, frazzle and reduce them in a Kafkaesque manner to insects that pass through them in a devastating and blistering abandonment.”

Squares as a medium for biodiversity

While the “plaza dura” had made a large number of enemies, climate change may put an end to its prestige among municipal architects and technicians. Hard-surfaced squares make an extraordinary contribution to the well-documented heat island effect, a phenomenon whereby the temperature in cities is repeatedly higher throughout the year than in a rural area some 10 km away. In most of the main Spanish urban areas (Madrid, Barcelona and Valencia), the rise in temperatures has stabilised permanently in recent years, ranging between 2º and 3ºC.[1]

Public, institutional and technical awareness that cities should support biodiversity could be the final key element that convinces us, as citizens, to dispense with this model. The places that can support biodiversity in the city are very limited. These include the remains of the natural landscape that have been preserved within cities; waste ground – which, in many cases, can only made a temporary contribution –; public parks and gardens; private patios and gardens; as well as some balconies and a number of green roofs or rooftop gardens.

Additional parameters

For this limited set of spaces to become an effective medium for biodiversity, there are additional parameters that must be met, such as size, quality, pattern, connectivity and diversity. Size is one of the most critical elements. The fragmentation and isolation of urban green spaces has been well defined in the United Kingdom, where it is estimated that only 13% of urban trees are found in green spaces over 0.25 hectares. This statistical average contrasts with the indication that only areas between 10 and 35 hectares are capable of supporting, on their own, urban species (both those that use them temporarily and their permanent inhabitants).

When these large natural spaces of between 10 and 35 hectares do not exist in a large area of the city, the medium can only be provided by a network of smaller spaces whose size and proximity are of paramount importance. The decision to build hard-surfaced squares means depriving urban centres of a space of over two hectares (such as Plaça dels Països Catalans, in Barcelona) or one hectare (Plaza de la Encarnación, in Seville) where the medium for biodiversity depends on the creation of a network that is normally missing nodes. In areas such as the Centro district in Madrid, only the network that would comprise all the squares, such as the Plaza de Callao (0.5 ha), Puerta del Sol (1.2 ha), the Plaza de Santo Domingo (0.35 ha) and the Plaza Mayor (1.2 ha), among others, could very tentatively come near the creation of an effective medium to support biodiversity.

[1] Center for International Earth Science Information Network (CIESIN)/Columbia University, 2016, Global Urban Heat Island (UNI), data set, 2013. Palisades, New York, NASA’s Socioeconomic Data and Applications Centre (SEDAC).

In the city, singular elements do not only include squares, corners, monuments or green spaces; they are part of a network that may or may not facilitate the preservation of collective health or the environment. The city’s open spaces, seen from an agenda that advocates urban biodiversity, must be part of a matrix structure in which the “urban patches” become the nodes of a network (Breuste 2008, Wu 2008). The strategy is to generate a network with as many intersections as possible and connect them through proximity and diversity relationships. This calls for a change in the vision of the city: to understand the pattern formed by the different elements beyond the elements themselves. The recent controversy generated in the media about whether the next reform of Madrid’s Puerta del Sol should have trees or not is a good example of the need for a change in the way the city is observed and analysed. The arguments focussed on the need to hold events, on the importance of seeing the complete facades in a historic setting and even, somewhat rightly, blaming the architects for not knowing about landscaping. Among the reasons given, no one thought about the distance to the nearest shaded area, green space or fountain, and whether they formed a dense pattern or if their continuity depended on the Puerta del Sol. The survival, or at least the minimum comfort, of many species in the city, would include, among others, a portion of the human species with determining factors based on age, health or economic availability and biologically depends on the strength of that network.

Heterogeneity is another key aspect in the design of biodiverse urban spaces. Many species need different natural spaces for their survival. The seasons make a major difference in the needs of living things: they may require shade and moisture in summer and, in winter, the opposite. These different needs also affect the animal species throughout the different life stages. If we produce heterogeneous environments, living beings can build, according to their needs, a life path with different periods of use in different environments. In this regard, the strategy that is good for bees, sparrows or squirrels is equally good for humans, who have varying needs according to the season and stage of life.

Heterogeneous solutions versus clean solutions

Those who practise architecture have been educated to homogenise the environment, among other reasons because, from the point of view of the designer, it is a much more “economical” process (I come up with a solution that seems good to me and I repeat it), versus the commitment to heterogeneity (I not only have to think of several solutions, but also deal with the problems that surface when mixing them). Both councillors and architecture professionals have systematically positioned themselves in favour of “cleaner solutions”, as defined by the current mayor of Madrid, José Luis Martínez-Almeida, as the solution to redevelop the Puerta del Sol, so extremely hard that it proposes a total absence of vegetation. This project was the subject of a competition organised by the Madrid Architects’ Association in 2014, won by Linazasoro & Sánchez Arquitectura.

To defend this type of proposal, arguments such as the need to preserve the historical heritage are used, but we have to remember that the Plaza Mayor in Madrid had, like so many others, trees and fountains until 1927. The choice of the hard-surfaced square should be vehemently contested by citizens because it represents a serious issue for their health and well-being and the survival of living species in the city. Hasn’t Covid-19 taught us anything about the appropriateness of putting the economy ahead of health and the environment? The technical (underground structures) or longstanding arguments can all be questioned or beaten. The only compelling reasons to prioritise the hard-surfaced square are, again, to give precedence to productive activities (cleaning, security, control of public order, advertising, commerce and the organisation of profit-making events) over citizens, the environment and health, an approach that this article invites readers to challenge as erroneous and, if you wish to be more perverse, to understand it as a means to preserve a visual culture of order and cleanliness that allows architects educated in the Modern Movement to differentiate their aesthetic preferences from those of ordinary folk.

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