8 cc International Biennial of Landscape Architecture
September 2014 Barcelona 25, 26 & 27 september
Country University / School Academic year Title of the project Authors
The Netherlands Wageningen University 2012 - 2013 Steering Protective Growth Jeroen Castricum, Dirk Harden
2013: 13,8 million inhabitants
The north, east and
west of the province is largely forested and hosts drinking
Turkey
water basins (dammed watersheds)
Fresh water basin in use Polluted fresh water basin
Problem introduction
^ The urbanizing landscape of Maslak, Sisli (photo by Serkan Taycan)
The urban landscape of Istanbul is for a large part shaped and organized by the steering forces of supply and demand. The newly envisioned infrastructure will pull off unplanned forms of urban growth that neglects the underlying landscape and its resources. The city has already reached its growth limits, and is starting to grow inside its drinking water basins, mostly located in the forest belt surrounding the city. Forests have a major role in purifying rainwater to drinking water quality, and at the same time provide many other ecosystem services for the city. With an increase of urban areas inside these basins, forest areas will decrease and pollution will be insurmountable. As a result, the growing city puts a valuable landscape resource at risk. The city is cutting off its own lifelines.
H+N+S Landscape Architects and 51N4E constructed a vision for the Sazlıdere basin for the International Architecture Biennale Rotterdam (IABR) 2012, in which the water resource is protected while urbanization continues. This basin is characterized by agriculture.
The design of this project is located in Alibeyköy basin, near the urban area of Arnavutköy. Like many basins, this basin is located in the forest belt.
Projection 2030: 17-22 million inhabitants
40% to 90% in built-up increase of
area in the coming two decades
Like many fast growing cities, Istanbul lacks a
detailed planning strategy and legislation. In this
case, magnets tend to have a stronger influence on the direction and organization of urban growth.
Fresh water basin in use Polluted fresh water basin
Aim and Research question The aim of this research is to develop new design strategies for protecting resource landscapes in the vicinity of unplanned, rapid growing cities like Istanbul, in order to retain the living standards in growing cities.This research will be focused on a water basin characterized by large forests. This led to the following research question. How to preserve the fresh water resource of Istanbul while allowing urban growth in a basin that contains parts of the forest belt of Istanbul?
Exploring the urbanizing landscape It is impossible to get a complete view on the elements that steer and organize Istanbul’s urban growth. However, on a large scale the strong effect of such elements can be made clear. In this research the term ‘magnet‘ is used to understand and depict the steering and organizing power of spatial elements for the growing city. So, magnets are spatial elements guiding and organizing urban growth. Magnets are not a precondition for urban development like landscape resources. However, besides steering and organizing urban growth, they can accelerate urban growth.
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Presently Istanbul is constructing more large infrastructures inside the forest belt (highways, airport). These new magnets will also attract many new developments towards the basin Alibeyköy.
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10 km
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< In ancient times the Bosphorus Strait and natural bays, which functioned as harbors, were examples of attracting magnets for urban development. Later, the Bosphorus bridges and inland highways got increasingly important for trade and urban development.
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Existing situation in former mine area
Vision for the Alibeyköy basin
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The constructed vision proposes to use urban pressure to revitalize disrupted landscapes to improve and protect drinking water resources. With the right design for the disrupted former mining area, urban development can improve and protect the drinking water resource, while urban growth is allowed.
Project
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location
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Arnavutköy
Landscape analysis of the former mining area
^ Infrastructural connections to Istanbul’s business centers (orange), and the ‘empty’ lands are strong magnets for development.
The former mining area is surrounded by magnets that make the area very attractive for high-class development: nearby facilities of Arnavutköy, a nearby highway connection to Istanbul’s business centers, scenic forests, more planned highway connections and a planned airport. Moreover, the area is a unique scenic landscape in itself. The man-made landscape is characterized by many lakes with steep cliffs on the forest edge. However, the scenic landscape is endangered by construction waste from the city, which is dumped into the lakes. Between the lakes and the city of Arnavutköy a ‘dump truck landscape’ can be found: a hilly, plateau-like landscape with small ponds, created by dump trucks that used to dump leftover material from the mines. The area is characterized by a centripetal water system: The mine lakes collect run-off water from the surrounding landscape. Then water flows from the mine lakes through the main stream towards the Alibeyköy reservoir where water is stored and filtered for domestic use.
Sazlıdere Alibey
^ Vision for the Alibeyköy basin Revitalize disrupted areas to improve and protect water resources and allow urban growth.
< A model has been created based on one of the centripetal lakes. Here, the model summarizes characteristics of the landscape.
‘Dump truck landscape’: a hilly, plateau-like landscape with small ponds, created by dump trucks that used to dump leftover material from the mines.
Plan map
Using magnets as concept to design the
After construction
former mining area
Casco concept (Sijmons, 1991) Spatial incentive
2) Aqueducts 3) Potential urban area 4) Ridge 5) Dam to control water outflow of the lakes
view point bird eye view
6) Reed
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7) Main road to potential urban area
After 10-15 years 25.000 inhabitants
8) Placed magnets 9) Arnavutköy, existing urban area
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Repellers of urban development
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Education by 8
readability
(Hill, White et al. 2002) (Clayton, 2009)
(Duchhart, 2007)
Accessibility (Clayton, 2009)
Swarm planning (Roggema, 2012)
Multifunctionality (Lovell, 2009)
planning
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4
Overview of researched theory
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After 5-10 years 10.000 inhabitants
1) Framework landscape
A magnet has two polarities, which is used to form the concept. One side is the ‘attractor’; this side attracts developments. The other side of the magnet is the ‘repeller’; this side repels developments, and is able to protect certain areas from urban development by spatial implementations. Theories that provide guidelines on how to implement attractors and repellors as spatial elements inside the landscape can be seen in the figure below.
Attractors of urban development
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Making borders (Nassauer, 1995)
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Detailed design 7
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1000 M
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System design in a model
A revitalized landscape protected
The first step is to create a low-dynamic water framework based on the ‘casco concept’ that covers the entire project area, where water is purified and erosion is reduced. Potential urban areas are added to this landscape when water quality can be maintained. The higher edges in the dump truck landscape, formed by the edges of the micro-catchment of the centripetal lake, give opportunities for these potential urban areas. R
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STEP 2. Revitalising the landscape with available construction
To enable revitalization of the landscape, the continuous supply of construction waste is used to shallow the lakes and to build a terraced retention landscape that controls erosion. To create readable landscapes, the design solutions for erosion control of the potential urban areas are different from the solutions in the framework landscape. Stone retention walls are proposed in the potential urban areas at the slope of each plateau that will create an urban character. These walls can be up to 5 meters high to make clear borders and ‘frame nature’. Vegetated earth banks have the same function inside the framework landscape, but have a natural character. By maintaining the lakes the unique scenic landscape continues to exist, and will attract urban developers.
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[C1]
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[A] Living in a water resource landscape. The orifice weir is designed to create an experienceable water flow.
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[B] Scenic views at the aqueduct on the cliffs.
The design of the former mine landscape is explained in four steps, on the left. The axonometric landscape model forms the basis to create a systematic design. These four steps in the model have been applied to the former mining landscape, resulting in the plan map. Magnets like infrastructures, facilities, prepared plots, and public spaces that will attract development are located in the potential urban areas, nearby the urban area of the Arnavutköy municipality. In this way, the first developments can be close to the facilities of Arnavutköy, and have as well a view on the scenic landscape. By placing the first magnets here, high-class development will start to grow from the ridge of the different centripetal lakes. This gives the option to keep an eye on the water quality when development continues down the slope.
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[C1]
Detailed design [C2]
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by urban growth
STEP 1. Implementing the ‘casco concept’
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[C2]
[D]
Magnets that attract urban development - Infrastructure A - Prepared plots - Reserved space for facilities - Presence of scenic views
[D]
Magnets that repel urban development: - Paths and additional R recreation points create recreation landscape - Educational water elements - Preservation of scenic views
[C2]
STEP 3 Strengthen the fresh water resource landscape
The landscape function as a fresh water resource landscape is strengthened. In the framework landscape, orifice weirs are constructed to slow down the discharge of rainwater. Dams at the outflow of each mine lake actively regulate water levels inside the lake. Constructed wetlands are proposed to filter the surplus of nutrients and aqueducts along the cliffs will stop local erosion. In the potential urban areas, drains and retention ponds are constructed for run-off control and water purification. Again, different design solutions with an urban character define the space for urban development.
[B]
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[D]
[C1]
[B]
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2
[A]
[A]
5
[C1]
1) Access road from Arnavutköy
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STEP 4 Placing magnets to attract and repel developments
Placed magnets that attract and repel development alter the local projection of high-class developments. Attractors like local facilities and prepared plots will guide developments towards the potential urban areas. Recreational routes, destinations, unique spots and the landscape itself will attract local inhabitants and visitors, an additional target group to support protection of the landscape and its resource. All unique spots inside the landscape are related to the water system and educate people on how the water system works. A
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[B] [A]
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3) Gralux recreation path
150 M
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100 m
2) Retention ponds
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[D]
4) Mosque directed towards Mecca (reserved space) 5) Central carparking
^ Urban fabric based on the traditional Turkish urban form > Sections of the retention walls (C) and developing vegetated earth-banked terraces (D).
By investigating existing magnets for development in an area, future developments can be predicted. This project shows that by adjusting and adding magnets that repel and attract development, and by adding readable borders, urban developments can be steered to give room for a valuable water resource. Landscape architecture can provide the unplanned growing city with site-specific solutions for revitalizing landscapes, while allowing urban growth. Through landscape design, people can be involved in the protection of the water resource. Innovations in architecture and urban design can further increase the possibilities for living in a recovering water resource landscape. In Istanbul, it is crucial to promote the collaboration between water authorities and project developers to realize neighborhoods that protect their fresh water resources.
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