Ecological Interventions in Dispersed Cities_Aryani Sari Rahmanti_Antwerp Design Stusio_2009

Katholieke Univerisiteit Leven Faculty of Engineering Department of Arcitectecture, Urbanism and Planning Kasteelpark Arenberg 1 3001 Heverlee Belgium Academic year 2008 – 2009

Post graduate Master Programmes MaHS MaUSP Master of Human Settlements Master of Urbanism and Strategic Planning

Thesis submitted to obtain the degree: “Master of Human Settlements”

Title: Ecological Interventions in Dispersed Cities

Promotor

: Paola Vigano Erik Van Daele

Reader

: Paola Vigano

Student : Aryani Sari Rahmanti

Ecological Interventions in Dispersed Cities

Aryani Sari Rahmanti

Thesis Report

MaHS

20082009

KU Leuven

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Abstract This paper is aimed to give an understanding of ecological role and enhancement of natural and left over open spaces potentials related to the effort of strengthening the river corridor as part of planning consideration and strategy in between the pressure of sprawling settlements, particularly along Scheldt River and Struisbeek as its tributaries. This ecological involvement is expected not only to sustain the biological richness that the river has to lessen the crisis of ecology, but also to enrich and to be able to domesticate the unabated urbanization. The paper starts with an investigation of Scheldt River as an object of ecology with observation of both values and inferiorities that Scheldt River is facing. Secondly, notions of corridor and ecotones with the correlation and interpretation to the research of Scheldt will be the next focus. Third part will look at the attempts to reinforce, to minimize the fractures, and to intertwine ecology and urbanism by referring to the work of Antwerp Studio Water and Iron MaHS Spring Program 2008-2009. At last, the importance and meaning of ecological interventions, to lead the urbanism in sprawling cities towards their future directions of upgrading the environment quality with relation to the river, will be concluded as the final section of the paper.

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Content 0

Abstract __1

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Introduction __3

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Continuity, Connectivity, Fractions, Changes, and Overlaps __5 21

An Introduction to Ecology __5

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A River as an Object of Ecology: Measuring the Value of a River __5

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Contemporary Scheldt and Its Ecology __5 The Ecological Values The Crisis The River Corridor of Scheldt River

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Universal Concept for the Region of Scheldt River __11 31

Corridor __11

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Ecotones __12

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The Concepts in Urbanism __13

Scheldt and West Struisbeek: A Project of River Corridor Reinforcement In Between Two Cities __15 41

Story Behind the Project __15

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Closer to the Project __15

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West Struisbeek Project __18

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Small Interventions for the Major Ecological Network __22

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Conclusion __23

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Bibliography __24

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Appendix __25 I

Scheldt relief analysis

II

Scheldt hypothesis of overlapping ecosystems

III

Scheldt and ecological crisis

IV

West Struisbeek Project

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Introduction Urbanization will always search for a possibility for vacant lands to extend its territory for development. In many cases of present actuality, the consumption of the land has been in both expressions of formal or random urbanity. The city will diffuse itself until it has taken up considerable areas and many of the characteristics, the greenness, the fresh air, of what is now country, leads us to suppose also that the country will take to itself many of the qualities of the city. The boundary lines will altogether disappear… the railway and the new roads will spread… the character of the meshes in that wider network of roads will be the country, as distinguished from the urban district, will vary with the soil, the climate, and the tenure of the land… But throughout all that follows, this mere relativity of the new sort of town to the new sort off country over which the new sorts of people… will be scattered must be borne in mind1. The result is the extension and scattering of conurbations with bits and blots open spaces that are left behind.

Scheldt, one of the prominent river crossing over Belgium and the Netherlands, undergoes with this common but unique transpiration of complicatedness. The river still performs its role as natural and environmental quality barrier, especially in the areas influenced by the dynamic changes in the estuary giving impacts to the ecological affluence along the river itself and as well in the upland areas. But, settlements dispersal (Fig.1) has triggered the shrinking and sinking of spatial quality, in particular with respect to its ecological property.

Fig.1. Crumbs of settlements in Belgium region taking over open spaces in stages. Source: Image for Leie River analysis workshop, OSA KU Leuven (2009)

In the case like Scheldt River which comprises complex systems of natural and manmade environment lying on top each other, city ecology will change from a science which is used predominantly for the analysis and protection of the remaining landscape into a discipline which actively develops new forms of urban and cultural landscapes.

1

Thomas Sieverts and Hildebrand Frey foreword for Cities without Cities, An Interpretation of the Zwischenstadt, 2002.

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But, cities must again become strongly integrated with the surrounding landscape.

The city of tomorrow will consist of a concentration of compact settlements surrounded and surrounding countryside, which meets specific functions. Open land as in internal structure of the city has the potential for water and material cycles.

The identity of the city is derived not only from the design and mode of functioning of the built-up area, but also from the undeveloped open, ‘vegetative areas’2.

This paper will convince the idea of marrying both ecology and urbanity potentialities as an urgent action that could guide this tendency, by extracting the ecological potentials and conflicts in Scheldt region to generate a general concept and implementation. The future improvement of environment and urban development in regional scale is hoped to be able to be piloted by giving an example of local project interventions.

2 Thomas Sieverts in his publication Cities without Cities, The living space of the majority mankind (2002,p.43)

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Continuity, Connectivity, Fractions, Changes, and Overlaps

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An Introduction to Ecology Waterfowl birds migrate corresponding to the pattern of the climate, relationship between insects and flowers sustaining pollination, occupying nature for agriculture and settlements‌ Our earth is a composition of living and non living thing which interact each other. There is dependency, interruption, domination, dynamism, natural and balancing process, discovered in the interactions and a formulation of this relationship between organisms and their environment in a scientific study is defined as ecology.

Ecology covers global to specific levels of interactions between two components: biotic factors or organisms and biotic or non living factors. To locate the position of river in ecology, including its adjacent corridor and as a non living component, it has significant roles as space provision for the species to live in (habitat), biodiversities provider, and conduit of movement for the species3.

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A River as an Object of Ecology: Measuring the Value of a River Rivers are the natural highways of all nations, not only leveling the round and removing obstacles from the path of the traveler, quenching his thirst and bearing him on their bosoms, but conducting him through the most interesting scenery, the most populous portions of the globe, and where the animal and vegetable kingdom attain their greatest perfection (H.D. Thoreau, A week on the Concord and Merrimack Rivers, 1849)4.

Differed from the other elements as a natural watercourse corridor constructing the nature or landscape, river has the advantage of being more dynamic. Flowing down from the spring until the sea, the mouth of the river reveals high numbers of organisms with their high productivity. In the system of estuary, a semi enclosed mouth of rivers but still freely open to the sea, due to the marine influences and intrusions, several habitats divulging the amount of biological diversity varieties last.

The role that a river plays is not only for ecology, but also enormously concerning urbanism. River is vital and used modestly in some areas to support human lives.

And nowadays, with its wider roles, river serves as well as mean for transportation, energy resources, place for waste disposal, and even as administrative boundary determination. Modifications of the river and its banks have been acted upon for water infrastructure, safety management, and other purposes. The pressure coming from the urban developments, indisputably, has disturbed the equilibrium of the ecology.

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Contemporary Scheldt and Its Ecology Measuring the ecology of the river should entail both investigations of the values and the crisis the river has experienced, since they will cause the quality in the ecosystems. This ecological conditions assessment is necessary as a basis of a planning5. From the critical assessment, it is expected that approaches and strategies will present as general guidelines.

3 The function of river in terms of ecology is more less derived from the use of river corridor, Land Mosacis, The ecology of landscape and regions by Foreman (1995:236).

4 Definition of rivers is cited from Land Mosaics, The ecology of landscape and regions (1995:208) by Foreman, which chapter is Stream and River Corridor.

5 Sybrad Challingi in his book Ecological Conditions narrates the inevitability to consider ecology as part of planning. He mentions a detailed landscape analysis of landscape-ecological structure and, more specifically landscape diversity, was important as planning considerations. Following his case studies and methodology in approaches to ecology and planning, bringing ecology and planning in this paper will explain about the research to understand the potentials and problems, the approach or strategies, and lastly the example case.

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Scheldt River between Belgium and Netherlands represents the experience of diverging ecosystems as a result of water dynamism. As a unique part of the surrounding landscape and nature, Scheldt River, apart from its important contribution to economy and transportation sectors, gives abundant ecological values particularly in the estuary area, where the water is on its highest dynamism.

Physical conditions related to the water, the such as geological richness, soil type, salt content in the water, and relief of the bottom surface as habitats, reveal strong relationship with biodiversity, where some organisms presenting and revealing ecological processes6, and types of landscapes.

The Values The force of marine water from North Sea has impacted on the range of water saltiness from the estuary until upland rivers in Antwerp. Indicating the quantity of dissolved solid salt in the body of water, which type of salt refers to Sodium Chloride (NaCl), the salinity of Scheldt is interpreted as six criteria7 altering smoothly from marine to freshwater (Fig.2). The saltiness of the water has some effects on the varieties of the soil types and as a consequence, vegetations and faunas are therefore affected according to the salt concentration, even when the salt is in small number.

Fig.2.

Chart and classification of water salinity in Scheldt. Six zones of water saltiness can be determined from marine to freshwater.

Water transition can flow until Antwerp agglomeration (the fourth star) as the sea intrudes the river twice a day. Source: Antwerp Region Studio Spring 2008, KU Leuven from Scaldit report.

Soil type along the river corridor, natural body of earth which composition is fine ground rock particles of sand, silt, and clay, with several mineral particles, as well alters in stages as the salinity. Several soil types referring to the content of the water and salt can be discovered (Fig.3).

6 7

Foreman’s definition of biodiversity in Landscape Ecology, 1986.

Measurement used is the salinity Venice Chart Ecological Interventions in Dispersed Cities

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Fig.3.

Soil types are characterized by the water, rain, and sedimentation. Six types of soil are found, from sandbank to clay soils.

Source: Antwerp Region Studio Spring 2009, KU Leuven from Geo-Vlaanderen

Another physical condition giving impact to the river and upland ecosystems as place to live is the depth of the river reveals the complexity of the relief (see Appendix I). North Sea has the deepest surface while the Scheldt estuary has the most varieties of the bottom surface, from 2 to 40. The surface becomes simpler and relatively flat when the river enters the inland area, where there are more controls as modifications of the river bank and river topography (of the water level) are found.

A complete ecology analysis should include the organisms. Six faunas representing several types of species are observed. An observation of floras as well implies the same conditions of classifications following the salinity, soil type conditions, and relief of the river, ranging from low to high vegetations. The following conclusive charts of fauna and flora biodiversities and their habitat limitations (Fig. 4 and Fig.5) indicate that the species stop at certain conditions, depending on the physical or geographical conditions such as salt contain in the water, relief of the river bottom, and mineral, nutrients, water content of the soil, as well as will be shown in the types of landscape analysis (Fig.6). The limitations of their existence alter in gradual and not discontinue dramatically.

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Clams Dover fish Shrimps Birds Freshwater fish

Fig.4. Fauna diversities along Scheldt, 1) seals, later classified as semi aquatic marine/ brackish species:, (2) dover fish aquatic marine species, (3) shrimps and clams as aquatic transition/brackish species, (4) fish, aquatic freshwater species, and (5) birds non aquatic species.

Source: Antwerp Region Studio Spring 2008, KU Leuven

Sorting the richness of ecology encompassing physical conditions and biodiversities in both macro and micro scale, an assumption of gradual changes in species composition and relative abundance occur along the corridor. The gradient corresponds to the environmental changes, colonization extinction pattern, or a product or disturbance8. Meanwhile when there is no exact edge effect found due to intermixing compartments of the adjacent communities, this overlapping or transition zone between communities applies for the definition of ecotones9.

The Crisis Human activities and as well the power from the nature has a consequence to ecological conflicts. Water pollution, modifications of the river morphology, settlements pressure, are one the common examples of human interferences that has caused ecology agitation as well as the desires from the natural processes such as the extreme tidal changes, surplus water volume leading to flooding, or increasing water level.

The pluralism of the river functions, as infrastructure where the industries are located in several places, has brought the declining of the biodiversity and intercession of ecological assets of the river.

8

Gradient is described by Godron and Foreman on their book publication of Landscape Ecology, 1986. Main conception about gradient is the gradual changes, especially in relation with the absent of clear edge or boundary.

9 The definition of ‘ecotones’ is developed from the term used in Landscape Ecology, Godron and Foreman, 1986. The idea of the overlapping will be the notion of the ecological strategies.

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Fig.5.Flora diversities along Scheldt.

Source: Antwerp Region Studio Spring 2008, KU Leuven

Fig.6 Landscape types of Scheldt and upland areas.

Landscape types are categorized by considering elements such as landscape structure, water salinity, soil type, vegetations, river width, and water bodies.

Source:

The Corridor of Scheldt River The river system is viewed as series of ecological gradients, a continuum. The gradual changes, gradient, also happens not only in the channel of the river itself, but also to the upland areas10.

River corridors are definitely the most dynamic place in many landscapes with fierce competition among human uses. If the issue of river corridor is observed, strips of vegetation that encloses a channel with flowing water, including the channel, its adjacent banks, the floodplains, and strips of the uplands11, the case of Scheldt River will be interpreted as an interrupted river corridor (Fig.7).

10

Foreman in Land Mosaics, The Ecology of Landscape and Regions, 1995. His theory of stream corridor is used to argue the analysis hypothesis.

11 Definition of the river corridor refers to Landscape Ecology, Foreman and Godron, 1986.

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As we realize that Scheldt is a natural gallery bonding its compartments and its different characters, and the will to maintain the ecological connectivity, to sustain the ecology systems, to be able to accommodate the changes, fractures, flexibility, to preserve the diversities, and to encourage the landscape character; is therefore emphasized. With ecological perspective, strengthening the river corridor will be the aim of making Scheldt River as the real ecological backbone. Considerations of potentials in the upland patches, tributaries, floodable areas, green infiltration in urbanized areas are included, that the river will have the ability to adjust and guide present and predicted situations, where overlaps of activities and communities are optimized (Fig. 8).

Fig. 7a, 7b, and 7c (from left to right). Fig. 7a and 7b are interpretations of ecological analysis of Scheldt River with its different ecological capacities and interruptions.

7c explains the strategy to maintain the river corridor.

Source:

Fig. 8.

Schematic diagram of vision and strategies of Scheldt River. Source: Antwerp Region Studio Spring 2008, KU Leuven

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Universal Concepts for the Region of Scheldt River With the objective to strengthen Scheldt river corridor, concepts of corridor and ecotones are tied. Longitudinal, perpendicular, and transversal strategies are introduced to strengthen and define the river corridor with an attempt to retain the connectivity and minimize the fractions likewise to optimize the overlaps of activities that suits the idea of ecotones.

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Corridor An air plane operating in a specific lane to fly and to land; shopping arcade; ribbon of vegetation; a passageway in a hotel that collects the rooms; some readable patterns that links places; an oriented route; rivers; all the different appearance articulate consistent idea about linking some locations, bonding compartments, and being definite as a passage. It can be an open or protected space, straight or narrow, continuous line or stepping stones, manmade or natural. The characteristic is bold and has dissimilar pattern with the others: corridor. Corridors can be characterized by its physical features, appears as a place which is definite, a narrow route that has certain direction, a tie, or space holding its components. What determines the meaning of a corridor is not all about continuity, but also concerning its purpose to connect.

In ecology, corridor is associated as strips that differ from their surroundings permeating the land. It contributes biodiversity protection, enhances water resource management, gives filter or barrier, creates identity or uniqueness, and provides dispersal route in nature12. The functions of corridor (Fig.9)13 as it has been mentioned previously are lumped further as follows: a. Habitat, living place b. Conduit, a medium for mobility c. Filter, to stop or sort for crossing transversally d. Source, as an area giving off e. Sink, as a basin to accommodate River as a corridor is defined as similar feature of both its distinctive internal body and the linear layer along the channel. It means the river corridor may cover the edge of stream channel, flood plain, the banks above the flood plain, and part of the upland above the banks. The possibilities of the corridor forms are narrow, wide, straight, curvy, and linear, with corridor elements of connectivity, breaks, and nodes controlling to the important movement medium and functioning as barrier (Fig.10).

Fig. 9. Diagram of corridor functions.

Source: Foreman (1995)

12 Six categories of vegetation corridor contribution by Foreman in Land Mosaics, The Ecology of Landscape and Regions, 1995.

13 Foreman in Land Mosaics, The Ecology of Landscape and Regions, 1995.

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Fig.10.

Physical characteristics of corridor.

Also refers in some way with the types of corridor.

Source: Foreman (1995)

Boundary or edge indicates the limit of corridor. Firstly, they can be identified very clearly with a sharp perimeter, high contrast. Secondly, border is present with smooth changes with several distributions of elements along the corridor (see page 8, for gradient). Again, the boundary or edge can be hard or soft, and following the corridor shapes, the outline of boundary or edge can be straight or curvy (Fig.11).

Fig. 11 The personalities of boundary and edges, in correlation with the corridor.

Source: Foreman (1995)

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Ecotones The gradual changes, soft or hard, wide or narrow, that creates a transitional area between two or more overlapping communities and as well contains more diversities, lead to the idea of ecotones (Fig.12). It may appear on the ground as a gradual blending of the two communities across a broad area, or it may manifest itself as a sharp boundary line (Krummholz).

Changes in the physical environment may produce a sharp boundary, as in the example of the interface between areas of forest and cleared land, paddy field, grass land. Elsewhere, a more gradually blended interface area will be found, where species from each community will be found together as well as unique local species.

Some time the ecotones area or overlapping area is wide, and in it a mosaic of patches of each vegetation type intermingle (Raposport, 1982).

Transitional zones of the ecotones have a contact zone with landscape elements and it is a unique, recognizable characteristics. The structure is usually linear with certain width, and the dimensions, structure, and functions are dynamic. The characteristics and intensity of ecological processes differ from adjacent elements14.

With more than one activity, than a singular habitat, stealing the perception of ecotones agrees to let the logic of future urbanity and ecology preservation encountering. Ecotones are the spaces of transformation and growth, a typical in border or edge conditions. Ecotones is a manifestation of a permissive model that facilitate the complexities and interwoven of different functions, plural occupations, expected to be able to communicate with the dynamism, the ability to accept changes without deteriorating in quality.

14

This explanation about ecotones is sourced from Baltic University, UUP, Sweden.

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Fig. 12 Schematic drawing of ecotones idea.

Source: http://www.basic.ncsu. edu/segap/index.html

Ecotones is an idea of the possibility of space that puts peripherals, fragmented structures, interspaces in the centre of spatial planning. There utilization is free, creative and can be multifarious. That concept is based on a comprehension of space with frontier terms. The focus is not on centers, self-contained forms and explicit attributes, such as reality spaces disallow alternatives, but on peripherals and spatial amphibologies – multiple typified as border spaces (N. Weixlbaumer, 2005).15

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The Concepts in Urbanism The definition of corridor and ecotones in urbanism should be broadened if we want to link them with urbanity. Ecology should be an advantage not only for nature, but also for the human and culture. Ecotones is viewed as similar issues but with wider thoughts. Landscape project to recover the landscape of Gallego River in Zuera, Spain, illustrates the disconnected conditions of the riverside from the city. The layers were there: edge with settlements was piles of dump, accumulated and abandoned intermediate area, and patches of grove on the river bank. External risk of flooding was already in a halfway stage and erosion has created unsafe environment. The project is challenge of dealing with the need of public space, ecological issues, hydraulic standards, and urban grid remodeling. The river therefore works as the main structuring element (Fig.13).

15 N. Weixlbaumer wrote an article for Grenzlandschaften; Austrian Landscape Research, Klagenfurt�, page 89, translated

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Fig. 13 Gallego River waterfront recovery, a study case of urban ecotones.

Plans of a shifting landscape with inundation timing. The need of public space combined with floodable area, ecology preservation, safety management, and urban quality upgrading left by the industrial boxes.

Source: www.aldayjover.com.

Scheldt River with its elongated watercourses explores the option of testing the researched theme of corridor and ecotones in urban design proposal in regional scale with ecology intertwining. The soft changes and overlapping activities taking place in Scheldt region, due to the cities dispersal, has put the increasing stress level in the river.

The aim of strengthening of Scheldt River corridor as the backbone by looking at the concepts of corridor and ecotones is where both ecology and development. Working with the water as an ever changing element and defining the corridor with smooth edges to consent to ecotones to happen are the tools of the design project.

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Scheldt and West Struisbeek: A Project of River Corridor Reinforcement In Between Two Cities

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Story Behind the Project The historical landscape (yesterday) For the analyses of the landscape you use a land registers out of the 19th century.

The current landscape (today) For the analyses you oppose the current to the historical characteristic landscape.

The future landscape (tomorrow) From the uprisings you predict future natural sceneries (G. Dullnig )16 Along the Scheldt’s stream named Struisbeek situated between two small cities, Hemiksem and Schelle of Antwerp agglomeration, potentials of ecological corridor in relation with water is still in coexistence with its complexity and complications. The stream flowing from highland in Antwerp to lowland in Scheldt valley is the only stream with remaining ecological corridor that crosses A12, the 7km width main highway connecting Antwerp and Brussels (Fig.13).

Fig.13. Positioning the project in region of Scheldt basin. Source: Antwerp Region Studio Spring 2008, KU Leuven from Google Earth

The potentials that are concealed by pressures of urbanity: heavy duty industrial sites, major infrastructure (both road and railways), and sprawling settlements, are generating both riversides of Scheldt and Struisbeek as the backside of built environment with undefined edges. Allowing these ad hoc developments to happen is a threat. Consequently, a reservation of void should be proposed to improve the degraded spatial quality of the area and mostly to persist with the ecological conception of strengthening Scheldt river corridor using the stream Struisbeek as a natural medium.

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Closer to the Project Positioning Struisbeek in Scheldt is comparable as seeing a branch of a tree. In a regional scale, the stream Struisbeek perpendicularly grips the linear stripes of housing, industries, and commercial developments, infrastructure, and vast green open space (Fig.14).

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G. Dullnig for Grenzlandschaften - EU-Erweiterung und Landschaftsentwicklung; Bundersministerium für Bildung, Wissenschaft und Kultur; Austrian Landscape Research, Klagenfurt 2005” page 76-77, translated Ecological Interventions in Dispersed Cities

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Fig.14.

Present conditions of Scheldt, Hemiksem, and Schelle in larger scale.

Source: Antwerp Region Studio Spring 2008, KU Leuven from Google Earth

This four meter perpendicular wide stream starting from a highland in Antwerp was wider and navigable than the existing, ecologically functioned with border of high vegetations (Fig.15). Settlements were not dominant, overwhelmed by open spaces of nature, landscape, and water related settlements figures: St. Bernardus Abbey in the mouth of Struisbeek (Fig.16) and the castles along the stream.

Fig.15 Ferraris Map of Hemiksem and Schelle.

Source: Ferraris Map.

Fig.16 Old images of St. Bernardus Abbey, Scheldt, and Struisbeek.

Water courses were part of the settlements.

Source: www. globalbeernetwork.com

The emergence of industrial revolution commenced new features of infrastructures (Fig.17). Both sides of riverbank of Scheldt and Struisbeek were partially modified for industries but the width was still kept for water infrastructure. Parallel to Scheldt and crossing over Struisbeek, railways serving the cities and industries were constructed. The development of settlements was following infrastructures, particularly the industries in order to obtain efficient connections. Scheldt and Struisbeek were significant as waterways. But at the same time, it was also the starting point of the ecology declining, together with the decreasing numbers and sizes of patches.

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Fig.17 Hemiksem and Schelle during industrial revolution era, the growing of settlements and linearity of major infrastructures.

Source: www.patrimonie.fr

Since then, developments have had tendencies to push towards the coridor of Scheldt and Struisbeek(Fig.18). The stream was canalized, the topography is manipulated by heightening it for development or embankment, and the land is replaced for industries. Few of the railway tracks linking the industries and station before stays idle for no use crossing no man’s lands. Safety management from flooding risks uses industrial platforms as dikes with leaking protection in several areas (See Appendix II-IV for site analysis).

national road n148 industries industries housing pressure abbey St. Bernardus housing pressure church plaza pockets of leisure places

Fig. 18 Present condition of the site with undefined edges and endless settlements sprawl. Source: Antwerp Region Studio Spring 2008, KU Leuven from Google Earth

railway

Present condition of both streams is a fragmented ecological elements and an absent of a coherent spatial quality and pockets, altough at the same time, some of the areas have undertaken some efforts to return again to the waters (such as water recreation fishing pond, parks, low standard of waterside pathways, and viewing benches along the steams). Compiled with small, different, and intricate elements along the two watercourses, Scheldt and Struisbeek, the challenge of the design elaborates the redefinition or a corridor by working with the edges and usage of water as an intermingling between ecology and urbanism. For that reason, interventions of ecology in between the diffusion of settlements are inititated, with the notions of corridor and ecotones.

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The West Struisbeek Project Schelle and Hemiksem are the phenomena of diffused sprawling Belgian cities, with incidental and scrappy developments. The cities sandwich the stream Struisbeek and are clipped by parallel structure of national road and railways. The traces of earlier situations (see Ferraris Map in Fig. 14) are barely recognized. Scheldt has more blotches of industrial sites and green corridors along both waterways have reduced.

City center or cultural places have no longer relationship with the waters. The usage of the lands for industries, housing, commercial, and heritage are sprinkled, eating the riverside space and, furthermore, both cities have no actual main public open space. Nature and ecological assets are there or diminishing, disregarded.

Meanwhile, attempts to animate the area along the stream have been also endeavored even though they are incomprehensive. Revitalizing the rivers and their corridors using water as natural dynamic and creating networks of leisure patches and defining the transition zones for ecology and urbanism are emphasized. Urban design plan in Fig. 20 explains the sequences of the project: the abbey, the public plaza, the new development, and the provision of future pathway to another project of east Struisbeek17.

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Fig. 19 bird view Aerial impression for West Struisbeek Project, a project of underpinning the river and the stream corridor.

Source: Antwerp Region Studio Spring 2008, KU Leuven.

The paper will refer to West Struisbeek Project only.

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Fig. 20 Plan of West Struisbeek project. Source: Antwerp Region Studio Spring 2008, KU Leuven.

Let the waters move, let them play some parts Lock putting away Scheldt and Struisbeek will be opened, releasing the brackish water from Scheldt interacting with the freshwater in Struisbeek. Stream corridor of Struisbeek will be wider and have higher water level. The contact of two kinds of waters will create higher ecological diversities along the riparian zones floodplain.

Related to the water is the safety issue. The dikes on the lower part of Struisbeek (part of Schelle) will be restructured with nodes as a ‘balcony’ to the pockets of leisure places. Relate to the water is the safety issues. The upper bank of Struisbeek uses natural height of the topography as water barrier. On the lower part, new dikes can be proposed to be appropriate for the needs of safety. The character will be different with the other bank, which is a mixture of hard (engineered) and soft (allowing the continuity of the riparian vegetations) protection. Both sides of the back will create more wetlands and therefore, ecology is looked forward to happening.

To manage the risk of flooding from the rain water, catchment areas are proposed in different places. Water storage merged with the landscape of St. Bernardus abbey is proposed as hydrological park, when it will be flooded during rainy days and drain to the Scheldt after a while (Fig.22). Ponds on the leisure pockets as well participate as water basins during the high rain season.

Fig. 21. Present and proposed water conditions.

Source: Antwerp Region Studio Spring 2008, KU Leuven.

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Fig. 22. Hydrological park as part of the abbey’s park (left image). Exindustrial platform partially used as floodable staircase where people can touch the water and nature can colonize.

Source: Antwerp Region Studio Spring 2008, KU Leuven.

Soft edges, smooth transition Edges of current situations are weak. The corridor of the river is taken slowly by developments instigating more no relation between the settlements and the river(s).

The attempt is to seek for maintenance of the space along the river corridor, to give the corridors definition, and to lay the activities on top of each other in the transition zones smoothening the changes.

Industries blocking St. Bernardus Abbey to Scheldt is relocated and stairs to touch the river becomes the countenance towards Hemiksem and Schelle through Struisbeek. The platform will be cut partially as floodable zone helping to grow the nature back (Fig.23).

Fig. 22. The character of the existing, hard and soft: the contrast with is maintained, but idea to restructure the edge is also proposed.

Source: Antwerp Region Studio Spring 2008, KU Leuven.

New housing or commerce developments are expected to have an orientation back to the stream. The river corridor will have a maximum offset area to protect the riparian banks and alterations of dwelling activities and the river corridor will be the semi public nodes towards the stream (Fig.24).

Fig. 23.

Floodable staircases of St. Bernardus Abbey’s platform. Source: Antwerp Region Studio Spring 2008, KU Leuven.

The quality of the St. Niklaas Kerk plaza is deteriorating with car parks, mushrooming houses, and open sport facilities. A three meter high dike cuts them off from the stream. On the dike, there is no chance to see neither the stream nor the plaza, but the backside of the houses. Rearrangement and new connection between river and plaza is proposed, the houses, parking, and sport fields will be rearranged (Fig.25).

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Fig. 24 (left).

New housing typology with duo faรงade introduction.

Upper floors of the houses are facing the stream. Pathway with nodes of planted public areas/nodes is giving inflection and strong points of orientation.

Tones of activities are overlying.

Fig.25 (below). Rearrangement of public plaza around St. Niklaas Kerk and a floodable amphitheater as landscape feature.

Source: Antwerp Region Studio Spring 2008, KU Leuven.

The dikes, as the continuous part of Struisbeek, perform as well as pathways in sequential experiences. The path consists of several zones for the users (pedestrian or bikers) are wide at the intersections between pathways and narrow with some resting nodes to appreciate the view towards the rivers and the abbey. The paths are sometimes far or close to Struisbeek, low or slightly higher, hidden by vegetations or open to the water (Fig.26).

Fig. 26 One of the examples of variations of the corridors. Source: Antwerp Region Studio Spring 2008, KU Leuven.

Overlaps with Irons, Networks Flowing underneath the national road N148 and railway, junction between Struisbeek and the two parallel lines is interesting to be accentuated. Existing massive building on the bridge of the national road is proposed to be a pilotis with open views towards the Struisbeek corridor (Fig.27). New stop for an upcoming infrastructure project of Belgian light rail is proposed to be on the top of the river, without disturbing the connectivity of the corridor. Existing railway connecting Hemiksem station and the industries located next to the abbey is used as the place to grow vegetations that give both humans and animals a guidance to arrive at the abbey, and lastly Scheldt.

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Fig. 27. Design proposal at the junctions of river and iron.

Connectivity and integration.

Source: Antwerp Region Studio Spring 2008, KU Leuven.

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Small Interventions for the Major Ecological Network Ecological corridor of Scheldt in this project is reinforced perpendicularly using Struisbeek as a natural tool. But the stream itself is already busy taking care of the small and different compartments of built areas that bit by bit are consuming the land of the stream corridor. Ecology is brought to interfere the developments by increasing the water volume in the stream and reshuffling the corridor, that. The water will regulate both ecology and rapid sprawl urbanization. It is expected that Scheldt River and Struisbeek will be recovered and establish larger networks of ecology in regional area, for the better environmentally urbanism in particular.

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5

Conclusion Scheldt River is one of the nature cases enduring both ecological role and intercession of sprawling urbanization. The value that Scheldt River has is irreplaceable, particularly for its ecological richness. Nowadays, the worthy ecological conditions of the river have been undermined gradually, particularly due to intercessions of human activities which will cause ecological decomposing. If the river with its conditions as it is now, predicting the future, the ecological balance will not be maintained, and the meaning of the river will be less.

Human will always try to conquer the nature for exploitation. As the metaphysical model of the two worlds places the man and nature in opposition to each other18, their interactions cannot be avoided. It is then how the notions is reversed, that ecological interventions can be brought together in the forms of urbanism. The notion to include ecology in urbanism, unorthodoxly, to understand, to carry the ecological conditions, is essential, from present towards future directions.

18

Cited from Descrates quote from Tjalinggii’s report for a doctorate degree, Ecological Conditions.

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6

Bibliography 1.

FOREMAN, T.T., Land Mosaics, The ecology of landscape and regions, Cambridge University Press, Cambridge, 1995.

2. FOREMAN, T.T., DRAMSTAD, W.E. & OLSON, J.D., Landscape Ecology Principles in Landscape Architecture and Land-Use Planning, Island Press, Washington, 1996.

3. FOREMAN, T.T. & GODRON, Michel, Landscape Ecology, Willey Publisher, New York, 1986.

4. SHANNON, Kelly, Landscape Urbanism Reader for Spring Course 2009, KU Leuven, Leuven, 2009.

5. SIEVERTS, Thomas, Cities without Cities, Spon Press, London, 2003.

6. TJALLINGII, Sybrand, Ecological Conditions, Proofschrifjt van de grad van doctor aan de Technische Universiteit Delft, Delft, 1996.

7. WALDHEIM, Charles, The Landscape Urbanism Reader, Princeton Architectural Press, New York, 2006.

8. XAVEER DE GREYTER ARCHITECTEN, After Sprawl, NAi Uitgevers, Rotterdam, 2002.

9. www.geovlaanderen.be, accessed on 20th March 2009.

10. www.hetzeeuwselandschap.nl/saeftinghe, accessed on 20th of March 2009.

11. www.scaldit.net, accessed on 4th of August 2009.

12. www.scheldenet.nl, accessed on 20th of March 2009.

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7

Appendix

I

Relief of Scheldt River and North Sea

II

Scheldt hypothesis of overlapping ecosystems

25

III

Scheldt Landscape Type

IV

Scheldt and the crisis

26

V

West Struisbeek Project

Analysis

27

Field work

Proposal - The Abbey

Proposal - Pocket valley (of leisure activities)

28

Proposal - New housing typology

29