[8]
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Strong urbanization forces many metropolises around the world to explore their boundaries for growth. In Istanbul, chaotic and unplanned urbanization threatens the water quality in the city’s surrounding water basins that provide clean fresh water for the city. The growing city is cutting its own lifelines [1]. Considering the city a complex adaptive system, dependent on resources provided by the landscape, the city is studied. It appeared that ‘magnets’, which are often part of the city itself, can describe the behavior of the growing, unplanned city. The defined magnets are spatial elements that guide and organize urban growth. Here we consider facilities, highway exits, waterways, bridges, scenic landscapes, but also disrupted or empty landscapes without a visible function, that can attract urban growth [2]. Scientific literature did not only confirm the attracting effect of certain spatial elements. Literature also shows the repelling side of the magnet: spatial elements that repel urban development. These can be spatial elements that educate people about the importance or function of a certain landscape. Multifunctional and accessible landscapes can create support for protection by involving larger group(s) of people. By making clear borders, people are more likely to accept nature [3]. This project investigates the use of landscape architecture in steering unplanned development by making use of magnets that attract and repel development, in order to secure the city’s fresh water resource. This means that urban development is not excluded. Instead, the project combines landscape interventions for securing water quality, with creation of local support for landscape protection by involving urban development.
2013 Project location
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[1]
[9]
The design creates a low-dynamic water framework that covers the entire project area, where water is purified and erosion is reduced. Potential urban areas are added when the quality of the water can be preserved. 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. Here, the water can be purified along its way to the out flowing stream of the lake. So, the water framework is able to improve water quality, despite of the degree of urban development in the potential urban areas. In the model, the white areas represent the locations in the water framework that can be used as potential urban areas. The local projection of gated communities will be used for constructing a revitalized water resource landscape. This type of development considers a scenic landscape as important, and can be used to protect and finance the new landscape.
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M������ ���� ������� ����� ����������� - Infrastructure - Prepared plots - Reserved space for facilities - Presence of scenic views M������ ���� ����� ����� �����������: - Paths and additional recreation points create recreation landscape - Educational water elements - Local support to protect scenic views
S��� 2 E�������� �������������� �� ��� ��������� ���� ��������� ������ ��������� Design solutions for erosion control appear in the entire water framework. To create readable landscapes, the design solutions for erosion control of the potential urban areas are different. In the water framework ‘vegetated earth-banked terraces‘ are used to reduce erosion, and have a green and more natural appearance. The design solutions used in potential urban areas are stone retention walls, and create an urban atmosphere. Part of the construction waste, which is now being dumped in the lakes, is used as a building material for those walls. The wall defining the edge of possible urban development is over-dimensioned to create a strong and readable border for development. This wall is also a mean for “framing nature”.
[9A]
2013 Project location
S��� 3 S������������ ��������� �������� ���� ��������� ������ ��������� To strengthen the function as a fresh water resource landscape, design solutions are again different for the potential urban areas, to create a readable landscape. In the water framework, orifice weirs are constructed to slow down the discharge of rainwater, and to distribute the discharge over a larger time span. To increase water quality, also the cliffs are being protected from erosion. This is realized by constructing aquaducts (cut-off drains). In the water framework, water streams are allowed to flow freely through the landscape. To control water outflow, dams are constructed at the out-flowing stream of the lakes. The dams actively regulate the water level of the lakes. In this way, a part of the rainwater can be stored, and a continuous water flow to the streams can be created. In the parts of the landscape that can be potential urban areas, drains and retention ponds are constructed for run-off control and water purification. Like the stone retention walls, these elements have an urban character to define spaces for urban development.
Examples of magnets that attract urban growth: Waterways, bridges, roads, highways, and earthquake-safe areas.
Fresh water basin in use Polluted fresh water basin
[1]
P��������� 2030 Project location
[3] C���� ������� (Sijmons, 1991)
E�������� �� ����������� (Hill, White et al. 2002) (Clayton, 2009)
S������ ��������� �������� (Duchhart, 2007)
A������������ (Clayton, 2009)
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Fresh water basin in use Polluted fresh water basin
Attractors of urban development
[9B]
Retaining wall between the potential urban area and the framework landscape Retaining wall inside the potential urban area
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Retention ponds
The local projection of gated communities will be altered by placing magnets that attract and repel development. Magnets that repel development make a part of the landscape able to recover, in order to produce high quality fresh water. By adding recreation routes and spots to this landscape, this landscape becomes accessible and multifunctional. In this way, the water framework can also attract recreants, an additional target group that is likely to support protection of the landscape. The recreation routes and spots are based on the design solutions for erosion and run-off control. By doing this, the routes can give insights in the water system, and becomes educational. Elements that attract development, give room to urban growth, and attract high-class development. This target group is expected to support the protection of the local scenic landscape.
Repellers of urban development
Gralux recreation path Wooden recreation path Mosque directed towards Mecca as spatial incentive to attract development Place reserved for local shop
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[5]
Orifice weir with recreation route on top
150 M
Aqueduct on the cliffs along recreation path
[4] [12]
A ����������� ����� ��������� ��������� �� ����� ������
F����� ������ ��������� [4] This man-made landscape is characterized by lakes with steep cliffs up to 50 meters, separating the old forests from the mining landscape. The many lakes and cliffs make the landscape ecologically and aesthetically valuable. However, these lakes are endangered by construction waste from the city, which is dumped into the lakes. Between the lakes and the city of Arnavutköy the dump truck landscape can be found: A hilly landscape with small ponds, created by dump trucks that used to dump leftover material from the mines. C���������� ����� ������ [5] Mining activities resulted in a centripetal water system: The lakes collect the run-off water from the surrounding landscape. From the lake there is one out flowing stream to the main stream towards Alibey reservoir, where the water is collected.
The design steps presented in the model have been applied to the former mining landscape, as can be seen on the plan map. Magnets like infrastructure, facilities, prepared plots, and public spaces that will attract development are located in the potential urban areas, close to the urban area of Arnavutköy municipality. In this way, the first developments can be close to the facilities of Arnavutköy, as well have a view on the scenic landscape. By placing the first magnets here, the development will start to grow near the ridge of the different centripetal lakes. This gives the option to keep an eye on the water quality when development continues [8].
[9A]
For one of the centripetal lakes, a detailed design is presented. The form and location of vegetated earth-banked terraces, retention walls, orifice weirs, and drains is largely based on the underlying dump truck landscape. The steep slopes in the underlying landscape are also used as a guide for a large retention wall that creates a border for urban development. Vegetated earth-banked terraces are used to promote vegetation development and soil development, which will purify the water. [9][10][11]. New development can profit from the near recreation area, while the water resource provided by this landscape is better protected by support of the new neighbourhood. In this way the design gives an answer to the organization of unplanned urban development, and to the protection of a valuable landscape resource. The spatial elements that attract urban development are shown on a smaller scale, to show the possibilities of the constructed water landscape for creating a neighbourhood with a lot of green public space, where ecological understanding can arise. Stone retention walls and drains can be clear borders, which can be designed in order to define public spaces. Water flows are visible in the drains, while retention ponds create wetter places. At those wetter places trees are able to grow, to create shade, and to loosen the soil [12].
[6]
Forest on top of cliff with new aqueducts
[10]
[11]
[9B]
Lake with a reed bank
[12A]
Existing city
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Framework landscape with vegetated earth-banked terraces Potential urban area with retaining walls Ridge Dam to control water outflow of the lakes
[7]
Retaining wall that defines the hilltop
Access road from Arnavutköy
M����� ������� (Nassauer, 1995)
N����� �� ���������� The project location is located in the municipality of Arnavutköy. The local landscape is not only being disrupted by the rapid urbanization. Here, large empty lands recover from former mining activities. Strong erosion results in a decreased quality of the fresh water resource in the Alibey basin.
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[2]
P���������: 13,8 ������� (2012) 40%-90% �������� �� �����-�� ���� �� 2030
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Reed along stream
M���� [6] A model has been created based on one of the centripetal lakes. Here, the model summarizes the characteristics of the landscape. E������� ����� ������ [7] Different fabrics of urban growth have been identified. In the project area, gated communities are most likely to develop. In Istanbul, this kind of isolated high-class development is attracted by scenic landscapes, earthquake safe areas, and is located near highway exits. Gated communities are being developed on acquired private and state property. This kind of development is an important threat for the recovering of disrupted forested lands, which are a crucial part of the water system. Some of those attractors have been made visible on the aerial photograph above. One can see that gated communities are already being implemented in the area. These developments do not provide solutions for fresh water protection.
Main road to potential urban area in the former mine area towards Arnavutköy and Istanbul Placed magnets
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500 M
L�������� ������������ ��� ������� ����� ������ Landscape Architecture can provide the unplanned growing city with attractive and site-specific solutions for revitalizing disrupted landscapes, while allowing urban growth. This can be done by designing magnets that attract or repel development, and by designing clear borders for development. By design, people can be involved in the protection of the valuable fresh 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 neighbourhoods that protect their fresh water resources.
[12A]
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100 �