Plea2004 - The 21th Conference on Passive and Low Energy Architecture. Eindhoven, The Netherlands, 19 - 22 September 2004 Page 1 of 6

Sustainable Implant and EVA Centre, Culemborg; a hub for

Arjan van Timmeren1, Wiek Röling2 and Marleen Kaptein3

1 2 Faculty of Architecture, Delft University of Technology (D.U.T.), Delft, the Netherlands

3 Stichting EVA Centrum, Stichting EVA-Lanxmeer, Culemborg, the Netherlands

ABSTRACT: There is a rising need to interconnect different 'essential' flows inside cities at scales closer to users. Integration strategies for wastewater management and sanitation, even possibly together with energy-generation, comprise direct linking with neighboring subjects like agriculture (especially urban farming), aquaculture, horticulture and , urban planning, as well as in general and the organization, maintenance and assurance of indispensable parts of closed cycles. Ecological sanitation within these integrated projects will have to be based on a closed-cycle flow of nutrients. forms an excellent basis, for it is based on observation of natural systems, combined with modern science and technology, to create a cultivated ecology in which people more actively can get involved in different sustainable processes of change. This paper will focus on an important in urban development in the Netherlands: the strategic implementation of a network inter-connector, together with far going, innovative solutions for the generation of incoming flows and treatment of outgoing flows. It is situated in 'Lanxmeer', a nearly finished deep green urban district, based on permaculture and organic design principles, in the city of Culemborg. The final design of the so-called Sustainable Implant (SI) will be built together with the EVA-Center (Center for Ecological Guidance and Education) and externally works in coherence with an ecological city-farm. The SI works as an interconnector of the three ‘essential’ (or critical-) flows in urban planning. It not only facilitates the vertical- but also the horizontal integration of the concerning chains, nowadays a crucial development. The concept follows the main objectives of the ‘Small World’ principles of Watts & Strogatz [1]: Clustering, Emphasis on weak connections, Introduction of hub- nodes and the transformation from Egalitarian into Aristocratic networks. It can be considered as a sustainable hub within the existing centralised, non-aristocratic networks functioning at three different scales: the Culemborg region, the urban district Lanxmeer and the nearby EVA Center, which on its turn has been considered as a hub for Sustainable education and technology transfer on an international scale.

Conference Topic: 2 Design strategies and tools Keywords: decentralisation, integration strategies, small world principle, case-study

INTRODUCTION technology design. If we are to create a recycling society, we need to capture the wastes, render them The background of this research is the recognition safe and return them to productive resources again. of a need to compare alternative sustainable The linear thinking and actions follow an unconscious concepts, techniques and belonging structures on pattern, more and more being fed only by more aspects than the ones being indicated by the endogenous changes and existing centralisation existing paradigms and dominant actors in urban paradigms. Although useful, we should try to prevent planning. A paradigm is the whole of scientific the existing developments to become a ‘regressio ad performances of predecessors that by researchers infinitum’ (a retroversion into the infinite), due to and specialists on a certain field, on a certain moment ongoing displacements of goals or aims. A reflection in the development of science is being considered for on the structures that are underlying to urban normative [2]. Dominant actors in this light can be development is a necessary condition for Sustainable defined as: actors which are normative and who are Development as a whole. dominant in the determination of development- In addition to technical systems, the study tries to processes for a certain technology or structure. A demonstrate the need to include interdisciplinary paradigm, however is never the ultimate solution. Not approaches to the integration of strategies for raising even in case of unison of the dominant actors. Linear public awareness, marketing the different qualities of approaches to problems, in which resources are used water (cascading qualities) and energy (exergy), and and converted into wastes, only to be disposed of, establishing a service business for building and represent a failure in human ingenuity and a flaw in operating more decentralised installations. Integration Plea2004 - The 21th Conference on Passive and Low Energy Architecture. Eindhoven, The Netherlands, 19 - 22 September 2004 Page 2 of 6

strategies for wastewater management and called the ‘environment-circuit’ (Fig. 3) [10]. In this ‘E- sanitation, even possibly together with energy- circuit’ the chain in/out is specified to three main units: generation, comprise direct linking with neighboring extraction, production and consumption, which subjects like agriculture -especially urban farming-, through so-called leakage-flows have a continuous aquaculture, horticulture, health care and food relation with the ecological basis. security. The basis forms an urban planning that is recirculation of recirculation of based on ‘interconnection’, as well as waste materials and energy materials and energy management in general and the organization, (raw)materials products maintenance and assurance of indispensable parts of + energy + energy closed cycles. Besides of six small case studies extraction production consumption concerning parts of the main research hypothesis, in return materials return materials different fractions + energy (mainly raw mat.) of waste

one ‘integration case’ the outcome of the underlying energy + energy

and research is tested in a realised concept and belonging

device. The idea is to make urban development leakage flow leakage flow leakage flow materials following to the (social) needs and goals, which form of waste disposal

the basis of physical networks of the logistical chains, flow ("end of pipe") and not the other way around, like it can often be return qualified today. In this way it will be possible to leakage flow uncouple sustainable solutions from the existing 'ecological basis' / 'ecological field' (=self-sustaining environment) ‘centralisation-paradigm’, without the release of other relevant criteria for today’s society. Figure 2: The ‘environmental circuit’ [10]

2. Context: interconnection of networks An important link in the desired transformation of our society from one based on linear attitudes of

resources and wastes, towards a circular one, is a 2.1 Environmental circuit changed way of handling and For the notion ‘environment’ exist many (ecological) sanitation. Ecological sanitation is not definitions, varying in more or less generality. merely about a new latrine design. It comes down to Kristinsson [3] defines it for instance according to the thinking more in nutrients and raw materials than in way Lau Tze approached life [4] on earth (between wastes, which ‘are to be disposed’. It’s a new way of 604 and 163 AD): “environment is like the hole in a thinking: a ‘closed-loop-approach’, in which excreta wheel, the nothing around which everything rotates. If are returned to the soil instead of water. It comes it is not situated in the centre, it will start bumping, down to a (better) formalisation of the existing dislocate and stop rotating, start dragging and leave ‘leakage flows’ between the cultural world and the indelible traces”. Most of the Dutch environment natural world, or ‘ecological field’ as a self-sustaining related research however uses the definition which environment. In this way the closed-loop approach is describes environment as ‘the physical, non-living non-polluting, keeping fresh and marine water bodies and living, surroundings of society with which it has a free of pathogens and (too many) nutrients, while the reciprocal relation” [5]. More recent and general is the environmental and human health risks are minimised definition: “environment is the collection of conditions, or eliminated. necessary for life” [6]. The Dutch environmentalist Unfortunately, half of humanity still does not have Van Leeuwen [7] introduced within this definition the access to any type of sanitation. On the one hand this eco-device model with incoming and outgoing flows. is a threat to the ecological field. On the other hand it

still might be the basis for a critical look upon existing, ‘conventional’ approaches, which have been realised source problems: internal problems: sink problems: so far, and (mostly) are planned to be realised in - depletion adverse effects on - pollution - pollution - disturbance these parts of the world too. The dilemma is: fast- - disturbance - human health - ... - ... - urban functions arrangement of sanitation systems for the people who - plants, animals do not have access to sanitation (being a human right) and additional global environmental consequences, or ecological sanitation: on site Figure 1: Eco device model with incoming and systems with, especially in the beginning, a slower outgoing flows & related environmental problems [8] rate of implementation and therefore -in the beginning- not following the equity principle within Later the D.U.T. [8] linked the primary harmful Sustainable Development. That is, from the point of aspects for the environment to the in- and outgoing view of existing paradigms and a literally approach to flows, while the secondary harmful aspects were this equity principle. Apart from that, ecological coupled to the investigated system or area. The sanitation is valuable for a number of other reasons, disadvantage of the eco device scheme is its varying from better food production to secondary constrain to stochastic behaviour of input and output. benefits, like improvement of soil structure and water It is important to realise that environmental-effects holding capacity [11]. The two main design features of not only have to be negative. There can be positive ecological sanitation are urine-diversion and aspects too, which can possibly compensate to some composting techniques. In both cases it is possible to extent negative effects [9]. One has to see the eco- manage urine, faeces or excreta with little or no device in a larger framework: as a part of what is water. But to ensure an ecologically secure way of Plea2004 - The 21th Conference on Passive and Low Energy Architecture. Eindhoven, The Netherlands, 19 - 22 September 2004 Page 3 of 6

managing excreta it is important to combine these meter will raise, in the Dutch situation, in general with systems to energy production, for instance biogas a factor 50 to 60. The breakthrough of the almost production, and/or integrated food production. Within unfathomable deliberation of values concerning this these integrated projects concepts will have to be raise, or the bringing up of alternatives which explain based on a closed-cycle flow of nutrients. the illogically aspects of it, might lead to manageable Permaculture forms an excellent basis, for it is based tools [16]. Apart from that, the development of on observation of natural systems, combined with the building sites can be characterised as an almost experience of traditional farming methods and autonomous process, in which all parties out of their modern science and technology, to create a cultivated own background and paradigms make the highest ecology in which people more actively can get demands. There is no matter of mutual tuning in or involved. the putting up for debate of individual starting-points. Architects and installation advisors hardly are 2.2 Small World strategy interested in the at city district level. On the basis of the findings of the sociologist Even totally unnecessarily infrastructure is being Milgram about relations in social networks, also accepted as naturally. The (civil) engineer on its turn known as ‘six degrees of separation’ [12], the in general doesn't care for the real needs of mathematicians Watts and Strogatz were the first in infrastructure. The side effects are unnecessary high modelling the organisational and growth principles prices for building sites (before ‘building’ actually (also called the geometry or ‘architecture’) of starts) and almost impossible, or unaffordable complicated networks [1]. Watts and Strogatz studied flexibility for change towards sustainable alternatives. many ecological, social and physical networks, like Most of the times interesting alternatives are made the network of power lines in the United States. impossible due to the realised infrastructure or These networks turned out to have almost exactly the typology. The chosen infrastructure only facilitates same structure. They called these networks, with (less sustainable) forms of energy-, water- and waste certain innate intelligence, ‘small-world’ networks. related technologies. Some of the technical Especially the importance of (weak) connections, infrastructure even is superfluous. Besides, there is clustering and the underlying dynamic of no question of a possible fair comparison, for the interconnectedness in our world and necessary alternatives almost never are optimised to the urban- robustness, or error- (or attack-) tolerance of these and technology related aspects on the larger scale(s) continuously growing essential (physical) networks on of implementation. Most of the times the –supposed- which we all depend has become subject of several less important- environment-related aspects studies [13]. consequently are contracted out. For the case study the recognition of the network Apart from that the changing of certain qualities of architecture, or geometry therefore is essential for an the prepared sites are no subject of discussion: e.g. inclusion in structures (on larger scales) and possible strongly reduced (technical) infrastructure and simpler adaptation to increasing speed of change, without and less sizeable forms of execution, management loosing the necessary ambitions concerning and maintenance scarcely are brought in practice, and user security. with the consequence that governors don't (dare to) The concept follows the main objectives of the differ from the common path of practice and existing ‘Small World’ principles of Watts & Strogatz [1]: paradigms. Better tuning of infrastructure and use Clustering, Emphasis on weak connections, may lead to variable prices of sites and consequently Introduction of hub- nodes and the transformation to better opportunities for sustainable concepts. from Egalitarian into Aristocratic networks. Goal is to Although one should put forward that site prices show a possible implementation of this principle of depend on more aspects than the former stated, a re- transformation of the existing ‘egalitarian structures’ valuation will be useful. of the power grid and wastewater network (sewerage) The research concentrates on possibilities for in the neighbourhood into an aristocratic network interconnection of wastewater-, energy- and solid structure, with accompanying advantages [1]. waste related concepts. Especially its relation to the In that case the structures will have to transform (overhead) technical infrastructure and the into networks with the following features: a scale-free possibilities to bend these critical flows, for urban character and a distribution of transportation- development and sustainable life, into sustainable connections according to the principle of power-law cycles within autarky-approximating concepts. Scale- (also known as pareto of zipf) [14]. This principle is elements, like the covering of distances and seize of also indicated as a form of ‘self-organisation’. It can (ground related) space are getting more important be considered as the most important generic effect of every day. Apart from the lack of space in most growing networks or complex structures. Besides self- urbanised areas this is also the result of the ever repair, self-organisation is considered the most inclining environmental load of the existing, mostly important feature within green technologies, also aged technical infrastructure and the lack of space for known as ‘natural technologies’ [15]. Especially these replacing technical infrastructure due to off-written natural technologies form the basis of the within this existing technical infrastructure that stays in the research introduced concept of a Sustainable Implant. grounds as a residue [17]. In some areas in the Netherlands, but even in other countries with larger 2.3 Multiple use of ground areas and more non-urbanised space, the scale- When agricultural-, or non-cultivated land is being question concerning sustainable concepts, belonging transformed into for building sites, its price per square technical infrastructure and its use of ground also Plea2004 - The 21th Conference on Passive and Low Energy Architecture. Eindhoven, The Netherlands, 19 - 22 September 2004 Page 4 of 6

plays a part. In most of the realised projects that are subsequently large use of ground. Considering the based on the principles of Permaculture, this aspect use of ground of renewable, energy related of use of ground still is underexposed. technologies and the fact that most of the water In conventional projects, which are not developed on treatment solutions which are based on natural the basis of Permaculture, a consequence of the technologies and which are subsequently daylight need to transport energy, water and waste to dependant, this leads together with the ever centralised plants outside cities and consequently decreasing available space to the conclusion that the large technical infrastructure networks, is a belonging optimalisation of the use of natural light and use of use of energy, water and materials. These technical ground and daylight-related space(s) of surface have a non-negligible environmental dependant technologies should be investigated more impact and are relative expensive features in urban closely. Through the so-called multiple use of ground planning. Apart from that uncontrolled leakages, one can prevent the rejection of these small-scale inclining rotational speeds, changing technologies sustainable alternatives on account of unsustainably and especially aging of existing technical high costs, due to the relative large amount of needed infrastructure -in Europe in particular- will lead to ground surface. It might become the basis of new huge problems and costs within the next decades forms of Permaculture. [18]. More actual is the rising call for flexibility of (parts of) buildings and recently even entire districts 2.3 Offensive green planning or urbanisations. Precisely these 'flexibility-concepts' Existing green places and parks in and around can be connected to (a) clear optimum of scale(s). urbanised areas are pressurized by changed use or The conventional, more centralised solutions even miss-use, governance based on lowering nowadays still translate this 'flexibility-need’ into the maintenance costs, and urban extensions (and 'in’- creation of overcapacities of (technical) tensions). There is a rising call for a more offensive infrastructures, treatment- and generation systems. approach, using additive functions to preserve these Science -and more often the market too- brings up a green places against (claimed) more economical rising number of solutions that imply possible smaller developments. Ecological city farms and scales of implementation [17]. The consideration is a decentralised energy production- and water possible reduction of infrastructure and better visibility purification-systems integrated in these green areas and tuning in to the demand and therefore more can help to retain the green character, while it also flexibility. This paper focuses on the interconnection might function as an instrument to preserve the of sanitation (waste- & wastewater management) with original ecological- or agricultural structure, the food production and energy generation. Especially in ‘genius loci’. Moreover, it helps to revalue existing the field of small scale-, ecological sanitation systems cities, making them more liveable, by adding new important efforts have been made. The idea behind functions that facilitate residents to involve, and these kind of smaller systems, often based on natural therefore improves consciousness and commitment. technologies, is their relative simplicity and It is important to realize that liveability, together with adaptability, and therefore their possibility to create consciousness and commitment, is a precondition for extra (real sustainable) capacities in situations where sustainability. Conversely it is not. The aesthetic the centralised systems haven’t been built yet, the quality of the surroundings can be improved through existing systems (or surrounding environment) have the introduction of concepts like integrated reached the limits of their capacity (as a temporary decentralised water purification systems. The back-up), and in case of desired improved presence of water and natural systems in buildings, environmental performances e.g. through neighbourhoods and cities offers starting-points for interconnections with other ‘infra’ systems. However, landscape- or urban design. This goes especially for these kind of small scale, alternative systems most of separated strips of small, enclosed green areas, the times still are more expensive, because they are which now often have little or no spatial-, limited to pilot projects, and there is accordingly little environmental- or social function. Within the process ‘economy of scale’ in the production of components. of enduring worldwide urbanization, in the 21st The main cost factors, however, are the construction century the introduction of agriculture, horticulture and and maintenance of the belonging so called ‘micro- aquacultures may help to interconnect these networks’. This goes especially for small-scale necessary green places with social activities sewage networks [19]. Of course there are also other (gardening, food cultivation, recreation), more disadvantages. Sanitation for example is to a large sustainable solutions concerning neighbouring flows extent a social phenomenon, rather than a technical (wastewater, energy-generation, food production) and one. Therefore it is essential that background combined urban 'red/green' development. information on cultural, social-, economic- and environmental factors influencing sanitation behaviour is acquired before actual planning can start. This is 3. Sustainable Implant & EVA Centre especially true when a new technology is to be introduced. In case of systems based on natural 3.1 The Lanxmeer district in Culemborg technologies one does have to take into account that The project EVA-Lanxmeer concerns an these are vulnerable in case of inaccurate use or ecological settlement within the small-scale city of sabotage. Also they depend more on natural light and Culemborg, surrounded by a beautiful river among other things this means that these renewable landscape. The location of the EVA project is unique: sources have a relative low energy density and near the central railway station of Culemborg, on 24 Plea2004 - The 21th Conference on Passive and Low Energy Architecture. Eindhoven, The Netherlands, 19 - 22 September 2004 Page 5 of 6

hectares of agricultural land and some orchards. It is of that general principles of Permaculture affected the the first case in the Netherlands in which permission spatial structure of the plan, especially the green was given to build so near to-, and partially in- the zoning. There is a gradual transition from private-, protection zone of a drinking water extraction area. semi-private-, and public space towards a more Central governments allowed building at this site only natural landscape in the protected zone of the Water if guarantees were made that it was built carefully Company. Basis was the creation of four different according to modern ‘deep green’ principles. The green zones (actually five if one counts the private EVA Lanxmeer project started in 1994 with the gardens, within the open courtyards), which are founding of the ‘Stichting EVA’. In the following years, connected spatially and ecologically: (1) the collective plans were developed in full-cooperation with the gardens, as a part of the different building clusters, municipality, province and the drinking water supply- with playgrounds, relax areas and so called ‘edible and energy company. More innovative was the gardens’, (2) public green with retention ponds, integral participation of future residents and other extensive planting and reed beds, (3) agricultural relevant parties, like environmentalists, architects, grounds, city farm and orchards, and (4) ecological energy- & water specialists, landscaping architects, developing areas with infiltration ponds, woodland sociologists, right from the start (the initiative). The and ‘dry-’ & ‘wet’ hayfields. Together these green project is being realised in phases. In 1999 the first zones form an environment that displays the diversity phase, the construction of four clusters of 50 houses, and resilience of natural ecosystems. It can be called shaped around half-open courtyards started. At this the ‘Park of the 21st century’. Moreover because of moment the first two phases have been finished, the the added links to the (waste)water-, energy- and third, fourth and final phase have started or are under waste concept of Lanxmeer. The arrangement and development. Lanxmeer is prototypical for the use of the management of the four zones is oriented on decentralised systems (www.evalanxmeer.nl) [20]. , natural dynamism and a coherence The project EVA Lanxmeer offers conditions for between elements, places and processes. The living, working and recreation in a natural natural cycles are paramount within the overall environment, within the city conglomeration. It structure. The different zones are linked: (1) consists of approx. 200 houses and apartments, physically, through the design of watercourses, ecological office buildings, a biological city farm for (informal) paths, green belts and the recycling of ‘raw production, the EVA Centre (Education-, materials’, nutrients, plants and products; (2) spatially, Information- & Conference centre for Integral Ecology through the intensified experience of unity and ‘soft-‘ with Hotel), a Sustainable Implant (with Living and green delimitation between public and private Machine & Biogas generation plant, Retourette, E- areas; (3) ecological, through a larger diversity and Fulfilment), and collective permaculture gardens. vitality of the whole; and (4) socially, through the joint use and management, while (future) residents are 3.2 The ‘Park of the 21st century even invited to participate in several realisation The overall design of the district Lanxmeer and the processes, among which the design, building, architecture of the most of the buildings is based on management and further development of their permaculture and organic design principles (Fig.3). environment (‘experiencing is learning, eventually even acting…’) [20].

3.3 City farm – EVA Centre – Sustainable Implant The City Farm ‘Caetshage’ (near to an existing creek) and the EVA Centre (next to the railway station) form both the important ends (or beginnings) of the main east/west greenbelt that forms the backbone of Lanxmeer, with in the middle the former water tower, that is going to be re-developed too. The City Farm is situated in the originally agricultural area in front of the water extraction area. In buying houses the residents of Lanxmeer partly have contributed in the realisation costs. In return the residents can visit the farm freely, and if desired even can help with the maintenance of fields. The idea is that many people like to garden, but don’t have sufficient time to maintain their own kitchen garden. Nevertheless, the City Farm is supposed to work independently. Investigated is also to include a small-scale care- function. Apart from that, the City Farm offers

recreational facilities for the residents of Lanxmeer Figure 3: Detail of the urban plan of Lanxmeer with and Culemborg, Another important role is set aside to the Sustainable Implant connected to the EVA Centre the production of green waste of this City Farm.

Together with the remaining green waste of the other The structure of the urban plan is mainly based on green areas of Lanxmeer, the kitchen- and green the record of the existing landscape. Especially the waste of the houses (‘gft waste’) and Lanxmeer’s subterranean structure has been used for the overall sewage effluent, this is being transported to the plan, the water zoning- and ecological plan. Besides Plea2004 - The 21th Conference on Passive and Low Energy Architecture. Eindhoven, The Netherlands, 19 - 22 September 2004 Page 6 of 6

Biogas-plant within the concept of the Sustainable Implant, next to the EVA Centre. The role of this so- [1] Watts, D.J. & Strogatz, S.H. ‘Collective dynamics called Sustainable Implant (or: S.I.) is not only of small world networks’. Nature vol.393. (1998). ecologically, but also from the social-, participative [2] Hertog, F. den; Sluis, E. van. ‘Onderzoek in and educational point of view [21]. Separate water organisaties; een methodologische reisgids’. Van systems for drinking water and water for domestic use Gorcum & Comp. Assen. NL. (1995). are/will be installed in all houses, and also [3] Kristinsson, J. ‘Integraal Ontwerpen. Vitale decentralised separate sewage systems for 'grey' and Architectuur’. Kristinsson-Reitsema B.V. Deventer & 'black water'. Grey water is filtered in wetlands in the Aeneas. Boxtel. NL. (2002). centrally situated green ‘backbone’ of Lanxmeer and [4] Tau te King. ‘Lao Tse. Tao te King’. Transl.: Welz, fed into the surface water. 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(2000). belonging solutions, it would be better to introduce a [15] Todd, J. & Josephson, B. ‘The design of living ‘spatial infrastructure’: infrastructure being a design technologies for waste treatment, Ecological component of mixed ecological/spatial transformation engineering, nr. 6. (1996). processes. In introducing this design component [16] Kristinsson, J. ‘Infrastructuur, vooronderzoek’. quality related aspects (ecological, spatial and social) Sectie MilieuTechnisch Ontwerpen (MTO). can be linked to the (spatial) infrastructure and Bouwtechnologie. Faculteit Bouwkunde. Delft improve (the visualisation of) quantity related University of Technology. Delft. NL. (1993). solutions. Eventually leading to better consciousness [17] Lettinga, et al. 'Environmental protection and sustainability. It might prevent for future technologies for sustainable development'. in: Lens, ecological, spatial and eventually social problems due P. Zeeman, G. and Lettinga, G. 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