Adaptive landscapes

Constructing the Sustainable Delta-City Adaptive Landscapes

URBANISM EUROPEAN POSTGRADUATE MASTERS IN

EMU spring semester 2013 TUDelft

STRATEGIES AND DESIGN FOR CITIES AND TERRITORIES

URBANISM EUROPEAN POSTGRADUATE MASTERS IN

STRATEGIES AND DESIGN FOR CITIES AND TERRITORIES

European Postgraduate Master in Urbanism Student work design studio EMU spring semester 2013 TUDelft Constructing the Sustainable Delta-City European Higher Education Consortium in Urbanism Faculty of Architecture, Department of Urbanism Delft University of Technology Julianalaan 134 01WEST800 The Netherlands tel. +31 15 27 81298 EMU Coordinator TU Delft:

ir. Daan Zandbelt (d.d.zandbelt@tudelft.nl)

Websites: www.emurbanism.eu www.bk.tudelft.nl Course director:

Prof. dr. ir. V.J. Meyer

Responsible chair:

Urban Design & Landscape Architecture

Responsible coordinators:

Prof. dr. ir. V.J. Meyer (V.J.Meyer@tudelft.nl) ir. Inge Bobbink (I.Bobbink@tudelft.nl)

Course instructors:

Prof. dr. ir. V.J. Meyer (V.J.Meyer@tudelft.nl) ir. Inge Bobbink (I.Bobbink@tudelft.nl) dr. ir. Meta Berghauser Pont (M.Y.BerghauserPont@tudelft.nl)

Adaptive Landscapes Towards a resilient Delta

Contents

Luiz Carvalho, Hao Feng, Reshu Gupta, Mrudhula Koshy

4 Introduction Projects 16

Transforming Edge Hao Feng

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Towards a hospitable environment Reshu Gupta

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Heijplaat - Shifting Landscapes Luiz Carvalho

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Sculpting Terrains Mrudhula Koshi

Adaptive Urbanism Towards a resilient Delta

Introduction Delta regions formed by sedimentation and erosion of sea and river, contain the most vibrant and rich ecosystems in the world.The spring semester at European Mater Urbanism course, addresses the design and construction of urban form for one of these ecologically sensitive and changing dynamic deltas, that is - The Dutch Southwest Delta, Netherlands. The region in focus is the Rhine – Meuse Delta. Characterised with a variety of urban and landscape patterns, at present the region is struggling with new expectations and considerations concerning water management, flood defence, urbanization and landscape qualities.

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Location of the projects

1 - Transforming Edge

2 - Towards a hospitable environment

The site is Hellevoetsluis which is located in the entrance of the Haringvleit. . Now, there is a proposal that opening the Haringvliet dam. So the sea water will come into again.The edge of town has the opportunity to be hitted and destoryed. After analysis, I find that after opening the haringliet sluice there will be lots of sedimentation to be send to the edge of the town. So I come up with a concept that using the sedimentation to prevent the storm water. And according to the existing condition, there is two crisis grade. Therefore, I use two way to construct thses sedimentation. This process is a long process.

The sedimentation dike will be enhenced by the nature development.

The sedimentation will also be higher and higher with the water level rise. Also, the backbone used to contruct the sedimentation is also an extention of the existing urban green structure and allow people to have more access to the water and more waterlife.

The aim of the project Towards a hospitable environment is to create a setting for the towns of Sommelsdijk & Middelharnis and the region around, which is self-evolving.

As a flood defence measure, in some areas of historically reclaimed land, the land is given back to nature by breaching and removing dikes to allow flooding to occur (again).This is to restore former ecological character of Haringvliet estuary. Creeks are intensified to initiate local measures for flood defence and ensure fresh water supply.

At the local scale, it is a design that deals with urban expansion, flood defense and ecological landscape. The strategy takes into consideration existing water and natural landscape. Water layer contributes to the quality of place and is explored as a benefit. Residential developments are designed close to nature, to provide locals with an experience of landscape living.

Thus a synergic environment is envisioned for the polder cities in overall strategy of Adaptive Landscape, towards a resilient Delta.

3 - Heijplaat - Shifting Landscapes

4 - Sculpting Terrains

This study presents a strategy to deal with the ‘shifting landscape’ of port areas in order to advance a step further in a continuous process of transformation of the landscape, from marshlands to polder and then to port. Whatever the future concerning economy and water levels, the strategy tries to set the bases for a resilient future, trying to allow flexibility to adjust and at the same time to identify the important spatial values to be preserved and enhanced in future plans. The method used was first an analysis of the evolution of the place, its spatial characteristics and a comparative study with other similar cases. The strategy proposed is in the form of a framework that tries to safeguard spatial values, assure safety from water and improve connectivity and urban vitality in the area.

The last location in the regional strategy is the island of Dordrecht.

Inspite of being bounded by rivers on all sides, this city does not use the existing water networks to potential. The proposed transformation intends to bring back the relation which the city used to have with water.. This is tested in the south of Dordrecht by means of estuary restoration, creek widening and mounds by sedimentation.

The transformation intends to restore ecological benefits to the region. It proposes three diverse environments,. One is a relatively safe area, the second is subject to controlled flooding and the third aea is eventually transformed into an extension of Biesbosch and contributes to ‘Room for the river’. The ensuing urbanization also is with appropriate typologies and densities. It looks at re - distribution of urbanization to redue the urbanization in the north of the island. The island is eventually transformed into a resilient delta city by sculpting and moulding the terrain over 75 years.

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The Region

Evolution of the Delta

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Areas affected by the flood in 1953

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Samples of the diverse landscapes / urban fabrics of the region source - google maps

Scenarios

Water-safety interventions for the protection of the Rijnmond– Drechtsteden region have been primarily defined through four extreme, large scale strategies – so-called cornerstones (Deltacommissie Rijnmond – Drechtsteden, 2010). These are all based on the basic principle that the water level in an area protected by sea and river barriers is reduced, and hence the amount of dyke reinforcements necessary for protection is minimised. The choice of watersafety strategy at a large, regional scale has an impact on water levels throughout that region. Depending on the strategy chosen, additional water-safety interventions are required at a local scale, which affect spatial quality.

I Improved Closable A scenario that continues the present day Dutch water safety strategy; reinforce and improve the safety-level of the Maeslantkering - a large, flexible, storm surge barrier near Rotterdam. Reduce peaks in high water – levels in the region and strengthen the current dyke system.

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II Closable Open This scenario is an extension of the current strategy with flexible river barriers to prevent flooding in case high river discharges coincide with a storm surge from the North Sea. High-water levels in the protected area can be kept at an acceptable level and require relatively few local-scale interventions. Water levels upstream may rise, resulting in the need for additional water-safety measures in areas beyond the barriers.

III Closed Closed scenario eliminates the risk of failure inherent in flexible barriers of the closable but open type by using closed dams and locks.

Water levels in the urban area within the barrier system can be fully controlled and lowered.

IV Open Open system restores the naturally open connections between the North Sea, rivers and waterways in the Rhine Estuary– Drechtsteden; in case of a storm surge, any existing dams or flexible barriers are no longer used. This scenario leads to more extreme water-level fluctuations throughout the area and requires the strongest local-scale interventions.

In the shifting paradigm from ‘fight against water’ to ‘work with nature’, a closable open system as delineated by scenario II has been used as a basis for our regional strategy to propose various measures to counter flood risks. The sea level rise predicted by Delta Commission 2008 has been taken as the basis for deciding appropriate flood defence measures. The sea level is expected to rise to 1.3 m by 2100.

River Landscape - Urban Rotterdam

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River Landscape - Rural Haringvliet

The impact

When considering Closable Open scenario, various consequences are expected Tidal influence Opening the Haringvliet will lead to tidal influence which will have to be considered while ensuing flood risk management schemes.

Salinization The intrusion of salt water leading to a brackish water system is an immediate consequence. This would affect the towns thriving on an agricultural economy. The design solutions will have to take into account the anticipated transformation in economy.

An open system would inadvertently lead to an increase in water level. This would mean undertaking various measures to keep the land safe. A combination of hard and soft measures would be tested to counter this. The salt water intrusion also means that alternatives for fresh water storage or provisions will have to be found.

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Geo-morphological transformation Towns located at the mouth of Haringvliet, and those under the influence of tides would experience a natural transformation in geo – morphology. Most evident are the changes in erosion and sedimentation on the banks of Haringvliet, stirred erosion at the edge of Hellevoetsluis and rapid sedimentation at the edge of province of Middelharnis. Design solutions will have to cater to this change.

With the rise in sea level cities positioned inward would also be affected. For example, the city of Dordrecht lays in a vulnerable zone, and the design solutions have to take into account both, rising sea level and the river water level.

Economy As the port of Rotterdam is expected to gradually shift westwards, the economic function is poised for a shift. This offers various possibilities in terms of feasible combinations for a future for Rotterdam. The scope for large projects has reduced. The shift in power of governance from national to regional to sub – regional scale is also one of the contributing factors.

Influenced by the sea

Influenced by the sea and rivers

Change in the border of the areas influenced by sea and rivers caused by the adopetd scenario

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erosion sedimentation Areas where the processes of erosion and sedimention is expected to increase due to the major influence of the sea

The vision

In the current state the cities in the delta are unfortunately treated similar to any other city. This generic approach doesn’t explore the potentials of the delta. The areas surrounding the Haringvliet, Hollandsch Diep and Biesbosch are thought of as the far side of the Randstad than being a gateway to the delta. The delta is often considered as a subsidiary of the Randstad. Rotterdam for instance, is more often thought of as a city on the river than being a city on the delta.

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Until the beginning of the 20th century, urban form was shaped by the need to adapt cities to the potentials offered by the landscape, such as existing slopes, flood plains and local climate. However, with the advancement in technology, planners and designers distanced themselves from the bonds of nature. The stakeholders shaped the development. Even the architects came to regard landscape as a backward idea and gave prominence to the city. The city was viewed as the place where humans are in control, they viewed it as being the centre of culture and therefore the opposite of nature. Viewing cities and nature apart got deeply rooted to become a culture.

While urban development threatens to destroy the countryside and its nature, natural forces such as earthquakes and floods pose a threat to the city. This was felt closely by the low lands of Dutch deltas in the floods of 1953. Rather than presenting a solution, the

‘enemy’ myth of (nature and urban separate) causes problems for both resource and habitat management. They arise if human activities fail to take ecological processes into account and they persist if ecologists confine their activities to nature reserves or to wild life species. (Tjallingii, 2005) With this background we pose a vision for the dynamic landscape of deltas - An approach that coherently integrates urban and nature to achieve a balance between natural resources and urban requirements, an approach that is closely related to the ecological factor of the deltas. Instead of protecting natural ecosystems against the city, the aim is to make the city more ecological. Our vision is to bring focus to the delta by appropriately dealing with the flood risk that the region possesses by simultaneously envisioning the spatial development and ensuing ecological benefits for the next 100 years.

A fundamental revision in the hydraulic approach for the delta to develop a perspective for quality and land-use of the area that elaborate the urban and landscape typologies in combination with new organization of water and flood defence systems. Attention is paid to the issues of de-industrialization (as in case of Heijplaat), the need of new spatial and economic perspectives for the area (as in Dodrecht & Middelharnis) and the new potential possibilities of the riverfront area (as in Hellevoetsluis).

The strategy

Until recently, the emphasis of the strategies used to be on water safety, fresh water supply, nature and economic activity as separate layers while little attention was paid to the concept of spatial quality.

The natural condition of the delta had a balanced water and land ratio with no exerted pressure on land. This also meant that constant maintenance was not required. However, a systematic, continuous historical process transformed this condition by means of land reclamation, drainage and urbanization. This gave way to an induced condition. It led to a reduction in water surface which increased the pressure on the land. It also led to subsidence of land.

The constructed dikes required constant maintenance. Considering an inverted historical process can help alleviate some of the issues that came as a result of the historical process. This would balance the water – land ratio, reduce the pressure, rebuild a safe landscape and reduce the maintenance.

Integrated flood risk management would benefit the natural dynamics, cultural landscape and future urbanization in the context of a closable open delta. This also means envisioning an environment where the inhabitants are safer than ever and proud of living alongside water. Ways to integrate main infrastructure along with flood risk management would be tested at four various locations.

Our strategy tackles the transformation of Hellevoetsluis, Middelharnis, Heijphlaat and Dordrecht with each city adopting different measures for flood defence.

Regional water - safety strategies are being developed to protect delta regions from increasing flood risk. Local scale spatial qualities are to be formulated for realizing this. Dominant criteria for each area are used to define design criteria. The choice of a solution on a regional scale is shown to have a significant impact on the spatial quality on a local scale. Since our strategy deals with a closable but open system, depending on the chosen locations, room for the river in combination with natural transformation would be a feasible approach.

The port cities of Rotterdam and Dordrecht, located along the estuaries of the Rhine and Meuse rivers requires protection against storm surges from the North Sea and potentially concurrent, high river discharges from the rivers. (Deltacommissie, 2008) The complex challenge of flood risk management is no more solved using generic concepts as they require location specific precisions.

Hellevoetsluis and Middelharnis tackle the aspect of erosion and sedimentation respectively and look for ways to combine a natural transformation with flood risk management. Heijplaat looks at urban transformation once the port has moved westwards. The island of Dordrecht, under threats of a rise in water level from the sea and the rivers undergoes a long term strategy transformation by gradual fragmentation and estuary restoration.

All the locations are also tested for solutions which look at a changing ecological system due to the rise in sea level and rise in water level due to fluvial and pluvial floods. The shift in topography and urbanization are illustrated through a timeline of 50 to 100 years and various scales.

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Strategy test locations Existing creeks Urban areas Wetlands and marshes Railway lines Sea influence River influence Storm surge barrier

Room for the river

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Transforming Edge Hao Feng

Transforming Edge Hao Feng

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Site The site is Hellevoetsluis which is located in the entrance of the Haringvleit.

Problem Now, there is a proposal that opening the Haringvliet dam. So the sea water will come into again.

The storm in the north sea will go from south to north, so the north edge of the haringliet will more likely to be hitted and destoryed.

Aslo, the water level change will become bigger.

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River Depth

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Crisis Grade

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more crisis

Model

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Section

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Sedimentation

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This map show the sedimentation calculation process in the entrance of the Haringliet.

Concept

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The concept is to use the sedimentation to prevent the storm water.

Strategy

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small intervention

more intervention

Reference

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Plan

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Principle

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Relation to the city

extention of the existing city green stucture more life with water

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Perspective

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Towards a hospitable environment Reshu Gupta

Towards a hospitable environment Reshu Gupta

Problem statement To participate in the current course of working with nature, the emphasis of this work is towards the scenario of ‘closable open deltas’, with an aim to restore former ecological character of Haringvliet.

While we attempt to do so, the current fresh water lake of Haringvliet would turn to become salinized, directly affecting the present source of fresh water supply for agricultural land, demanding changes in economic and social processes. Thus, the problem statement for urban designers is, ‘How to maintain life in existing towns and create new conditions for quality living?’

ute towards regional and national priorities.The concepts of hydraulic engineering changing due to new theories concerning ‘building with nature’ and ‘room for the river’, with an increasing attention of the public to environmental issues and the rise of appreciation for the historic landscapes and urban patterns, a fundamental revision of the hydraulic approach for the region (Goeree Overflakke) is necessary.

Thus to create a spatial development interweaved into the landscape and water systems with the central design concept ‘the city should be good for water, but water can also be good for the city’, the Strategy of Two Networks is applied for the twin towns and region around.

Summary of the Project The Haringvliet runs parallel to the Nieuwe maas/Nieuwe Waterweg, just 15 km to the South. Here we find an open-water landscape of wetlands, rivers-capes, small urban settlements and marinas. The proximity of this river branch to the metropolitan region of Rotterdam – The Hague seems to be unexploited yet; the area offers a great potential for developing an attractive urban and recreational landscape. However the possibilities for new developments will be dependent from future water management strategy.

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In the current course of ecological development Haringvliet is discussed as in open scenario. In particular to the case of Sommelsdijk & Middelharnis, the area has to possibly take local measures, to contrib

The Strategy of Two Networks creates exceptional spatial conditions for the towns and for water & traffic flows. In the case of Sommelsdijk & Middelharnis, the resulting plan also crafts barrier free network for wildlife and offers opportunities for scenic routes for local traffic, cyclists and pedestrians.

As it takes into consideration the existing water and natural landscape as a starting point for design, S2N underpins the possibility to develop a unique identity for the twin towns alongside valuing the historic core of the towns.

Moreover, the strategy helped to identify locations for the possible expansions of residential areas which could be separated from infrastructural corridors and designed closer to nature, to provide locals with an experience of landscape living.

The plan proposes inundating a number of small polders, designed as a subsystem. Here new lakes for drinking water production can replace the existing sub-optimal agriculture land use. This would contribute to the visual quality, and also create interesting new options for wildlife and recreation.

fig 1: Location of Sommelsdijk & Middelharnis on Southwest Dutch Deltas.

Thus the area could gradually transform from only agricultural economy to attractive agricultural and recreational economy which supports not only people, but also plants and wildlife.

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fig 2: Creek side farm house in Middelharnis.

Source - Author’s archieve, 2013

Less urbanised settlements Sommelsdijk & Middelharnis

Most first settlements were built in river valleys and other places where water was easily available. Similarly, several settlements developed on the island of Goeree-Overflakkee in the province of South Holland, Netherlands. Among these classical villages originated the twin towns of Sommelsdijk & Middelharnis. Over a period of time the two towns fused into a residential area and now the town of Middelharnis alone has a population of about 6,780 (in 2012, CBS).

The common spatial arrangement in villages would be settlements around a Church (which served as a rescue point during the floods), a main street (voorstraat) and a harbor. The fig 5, fig 6, fig 7 show the Church, view of voorstraat and the inland habor in Middelharnis respectively. The area has a shopping center called D’n Diek that settled itself on a dike which used to be the last barrier for the town from the Haringvliet. The historic cores and the D’nDiek connecting the two centers, play in the region an important function, in particular to education, business services, retail and social facilities. So the spatial forms of the Church and the ring settlement around are valuable cultural heritage in the protected townscape.

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fig 3: (left) Sommelsdijk & Middelharnis situation in 1600. fig 4: Sommelsdijk & Middelharnis situation in 2000.

In the historic times, the main economy developed in the center of shipping/merchant and fishing which is reflected in the spatial development of intensive cultivated docklands and the development of a village center along the quay, between docklands and the front street. Sommelsdijk & Middelharnis towns have struggled for centuries to keep their ports accessible through channels between the Flakkeese - Plaat accretions along the dikes. See fig 3 & fig 4.The original creek structures have been modified largely during land reclamation for centuries. By the year 2000, new road network developed and several companies moved from the core to these new streets, accentuating a more generic development.

2000

fig 5: (clockwise) The Church of Middelharnis. fig 6: Voorstraat, Middelharnis.

Source - Author’s archieve, 2013

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fig 7: The inland harbor with connection to the Haringvliet.

Source - Author’s archieve, 2013

Historic evolution Goeree Overflakkee island

In the medieval period Goeree Overflakkee existed of dunes and multiple sand plates and was completely under the influence of tides and natural processes. The delta was a rich fishing ground and an ideal place for trade and thus for urbanization. So, in the 15th century, the first generation polders - the sand plates encircled by ring dikes were built.The early historic settlements developed at the creeks.The accretion of sediment to the dike ring created new sand plate which again was reclaimed for urbanization.

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The description of sedimentation and reclamation is depicted on the maps. The delta cities that were once on the edge of water were decades later positioned in cultivated land. Early delta cities transformed from a harbor city to a polder city.

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fig 8: Making of Goeree Overflakke island.

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Sommelsdijk & Middelharnis (1468)

Dirksland (1229)

Stadaan’t Haringvliet (1527)

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Herkingen Oude Tongue (1438) Nieuwe Tongue (1438)

fig 9: Historic towns on the island of Goeree Overflakkee Source - Author’s

Historic evolution Sommelsdijk & Middelharnis

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fig 10: Urbanization of Sommelsdijk & Middelharnis Source: Author’s

Sommelsdijk & Middelharnis contain historic housing in the church – ring – main street and harbor area. The housing are characterized by different rooftop styles as seen in the fig . The historic core structures have an integrated flood defense. The front door is elevated with 0.5m – 0.75m above street level. This solution works for height differences and slope of the dike.

fig 11: Elevated Front door, historic housing Middelharnis.

Source: Author’s archive

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fig 12: Roof profile historic housing Middelharnis.

Source: Author’s archive, 2013

fig 13: Housing typologies Middelharnis.

Source: Author’s archive, 2013

Historic evolution Sommelsdijk & Middelharnis

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fig 14: Spatial development for Sommelsdijk & Middelharnis.

Source: Author’s

The cities and their relation to the landscape changed through centuries. The cities in the Dutch Southwest Delta started as harbor cities but later were embedded into a polder landscape.

The urbanization process went through several phases, each related to a technological or socio – economic development.

fig 15: Spatial development for Sommelsdijk & Middelharnis 2010.

Source: Author’s

The harbor city The main street, voorstraat connected the Church with the harbor.

The polder city The post war development followed the line composition of the polder landscape.

Canals Water was collected in the drain reservoir to flush the extended canal at low tide, so the harbor remained accessible for ships. The harbor has a typical L-shape.

Recreation The development of recreation housing and day recreation in nearby polders lead to the cities first expansion outside of the polder of origin.

Agriculture Mills were constructed to provide towns their own flour. Ribbon settlements along dikes developed.

Vinex housing The recreation development attracted the development of Vinexlocations. These extensions are on water fronts.

Industries During the industrial revolution cities started to expand to main infrastructure.

fig 16: Residential development along creek, Middelharnis, 2013.

Photo: Author’s archive, 2013

fig 17: D n Diek, Middelharnis, 2013.

Photo: Author’s archieve, 2013

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Form analysis The landscape of the province of Middelharnis

The polder landscape of Goeree Overflakke contains of dikes and creeks.

The pattern of it is rigid. It is characterized by a ring dike that has followed the contours of the former sand plates. This ring is further divided into parcels of various sizes. The historic parcels have less rigid structure while the new parcels follow straight lines. The polder streams run parallel at the edge of the parcels and drain the water out to keep land dry.The creek is the main drainage of rain water and the polder parcels are oriented at these for water discharge.

The delta cities are located at the main creeks. After the flood of 1953, when most of the province of Middelharnis was flooded, the creeks structure has altered drastically.

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fig 18 :Polder landscape center Goeree Overflakkee island.

Source: Author’s, 2013 Data used: Map room, TU Delft Faculty of Architecture, 2013.

Creek Primary dike Other dike Highway Main polder road Polder streams Settelments

Past creeks Through the centuries the landscape has lost its large and characteristic creek system.The map shows the creek systems in the year 1943.

Creek Primary dike

fig 19: Creek system in 1943.

Source: Author’s, 2013 Data used: Map room, TU Delft Faculty of Architecture, 2013.

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Current creeks The map shows the current (2010) creek system state. Most of the historic or natural creeks have disappeared.

Creek Primary dike

fig 20: Creek system in 2010.

Source: Author’s, 2013 Data used: Map room, TU Delft Faculty of Architecture, 2013.

Research by design

Theory & methodology

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The Dutch have a long tradition of struggling against water. But there is a paradigm shift from fighting against water to working with nature [Meyer et al., 2010]. There are many theories and philosophies that are within the scope of working with nature. To define a theoretical framework for my design, literature by various authors were reviewed.

In the current paradigm of working with nature, urban design in the Dutch Southwest Delta and its towns should have a strong relation to the spatial conditions of the historical context of the landscape, building traditions, the natural processes that lead to form and the natural capital of ecosystems.

Working with nature

With the premise, in an existing natural and man-made spatial arrangement, for resource and habitat management, conditions will improve only if ecologists and urban planners work together towards ecological urban development. If so, what is the methodology involved to design ecological settlements that contribute to sustainable qualities of the development area? One of the design tools is The Strategy of Two Networks (S2N), which I adopted for my process of design solutions.

The paradigm working with nature implies an interactive relation between man and nature, and implicitly describes a relationship between the city and nature. It can be interpreted as a more submissive relation between man and nature and everything in between. The publication Ecological conditions by Tjallingi, states that there are different ways how people look at nature and these are determined by their world views or basic attitudes towards nature.

In this context, ‘object oriented’ and ‘process oriented’ theories are illustrated in the paper Ecology on the edge: landscape and ecology between town and country by same author. In the traditional object oriented approach, nature is part of a spatially and functionally defined separate territory. While working with nature relates to a process oriented approach, based on the theories of the resilient city and a shift from an increased awareness of the environment and landscape surrounding the delta cities, expressed as evolving yet balanced relation between city and nature.

Strategy of Two Networks The Strategy of Two Networks is a planning tool that uses the spatial networks of water and traffic system. The water network (drainage system, surface water & ground water) links urban development to local landscape. It provides opportunities for urban designers to create appropriate conditions for an integrated pattern of green areas. The traffic network is the carrier of economic processes. In the case of the province of Middelharnis, these two networks have played a vital role since historic times, expressed in the historical evolution study on next pages.

Problems

Potentials

- Polder cities are growing more as generic towns, lost historic identity - Demand for storage of excessive rainwater in the agriculture polder - Ensure drinking water supply - Low real estate (WOZ) - Poor spatial quality - Maintain population rate

- Nature living - Recreational opportunities - Ecologic potential - Energy source - Siltation fig 21: Current situation 2013.

Source: Author’s

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Creek Primary dike Other dike Highway Main polder road Polder streams

Creek Primary dike Other dike Highway Inundation polder Water storage

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fig 22: Map creek system restored Source: Author’s

Nature development, enhanced spatial experience

Inundated polder

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Current state of polder

fig 23: Polder transformation Source: Author’s

References Tjallingii, Sybrand. “Water Flows and Urban Planning.” Sustainable Urban Environments. Springer Netherlands, 2012. 91-111.

Tjallingii, Sybrand. “27 Carrying Structures: Urban Development Guided by Water and Traffic Networks.” SHIFTING SENSE: 355.

Tjallingii, Sybrand. “The Role of the Rain.”

McHarg, Ian L., and Lewis Mumford. Design with nature. New York: American Museum of Natural History, 1969.

Meyer, Han, Inge Bobbink, and Steffen Nijhuis, eds. Delta urbanism: the Netherlands. American Planning Association, 2010.

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Moudon, Anne Vernez. “A catholic approach to organizing what urban designers should know.” Journal of Planning Literature 6.4 (1992): 331- 349.

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Heijplaat - Shifting Landscapes Luiz Carvalho

Heijplaat - Shifting Landscapes Luiz Carvalho

Few cities in the world are so directly connected to the image of their ports as Rotterdam; here it is sometimes difficult to tell the limits of city and port. The case of Heijplaat and Stadshaven is one of the greatest examples of that close relationship, hence the fact that Heijplaat only exists because of the port. However the relation of port and city in the region in general and even stronger in that case must be readdressed. Port activities are changing and assuming a scale that is no longer compatible with the structure of one century ago, and at the same time neighbourhoods that were directly related to the port must discover a new role.

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This study presents a strategy to deal with the ‘shifting landscape’ of port areas in order to advance a step further in a continuous process of transformation of the landscape, from marshlands to polder and then to port. Whatever the future concerning economy and water levels, the strategy tries to set the bases for a resilient future, trying to allow flexibility to adjust and at the same time to identify the important spatial values to be preserved and enhanced in future plans.

The method used was first an analysis of the evolution of the place, its spatial characteristics and a comparative study with other similar cases. The strategy proposed is in the form of a framework that tries to safeguard spatial values, assure safety from water and improve connectivity and urban vitality in the area.

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Aerial view of the entrace of Waalhaven source: kust foto - Rijkswaterstaat

Historical evolution From wetland, to polder, to port, to city...

The analysis of the maps displaying the evolution of Heijplaat shows a direct connection of the transformations of the place with changes in economical activities. In the first moment the need to create room for agriculture and safeguard properties led to the construction of dikes and polders. Marshland is replaced by the grid of ditches and dikes; however some natural elements are still preserved like the creek.

When port activities become dominant in the area, the polders are replaced by docks and quays. This process is gradual and there is a clear connection in the design of the docks and the phasing of implementation with the lines and parcels of the polder.

In respect to the settlement in Heijplaat, in fact one of the first garden cities in the Netherlands, it is curious today to observe such a village surrounded by container parks, one can assume that the village was engulfed by the expansion of the port. The maps show that that is not the case; the village appears to house workers of the ship yards in the area.

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Evolution of the port of Rotterdam, filling the gaps between cities.

1340

1800

1920

Most of the area is still out of the dike ring and therefore subjected to floods, the koedood river is clearly the main structure of the place.

The expansion of the polder and dikes starting from Pernis and Charlois converge towards Heijplaat area, koedood river now is transformed into a boozer.

Begin of the construction of the docks, the structure of the polder´s parcel is to a certain extent used as guideline. The main water structure is still visible.

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1958

1963

2010

Expansion of the docks, again following the polders and dike structure, first expansion of Heijplaat. The water structure remaining from the koedood river is gone.

Docks expansion move to the other side of Heijplaat, here once more the lines of the dikes and polder still influenced the design of the quays.

Current situation where some docks have been land filled to house container parks. Although the area is outside the dike ring it is in higher levels than most of the city, around +3.90 NAP.

Spatial analysis Built typologies / Waterfront

Heijplat - garden city

Typical village designed under the principles of a polder city, with the three churches towers as main landmarks. The typology is predominant of houses with maximum two floors. The relation with the water front is limited due to the disposition of the blocks aligned with the main roads and tracks that give access to port activities.

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Heijplat - housing blocks Expansion of the original settlement, these 2 to 3 floors buildings are being partially demolished to give place to new buildings. The typology has not much to do with the rest of the village but at least the heights are not so expressive, the opposite of the buildings proposed to replace them.

Quarantine beach A rare example of water front that has not been embanked, the leafy area has a beach that is well appreciated by locals, the buildings, which are national monument, are currently used by an artist community. The access to the area is not so direct.

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Spatial analysis Built typologies / Waterfront

Warehouses One of the striking points in Heijplaat is the huge contrast between chalet like houses and the RDM warehouses, most of the buildings were designed to house ships under construction and other large scale parts. The relation with water is clear, mostly because of the former use of the buildings.

Logistic / comercial 64

Large parcels occupied by commercial or logistic functions, that part at the back of the port area is also used as a container park. The area has unusual green spaces for that type of programme. There are currently studies to implement new functions in the area in an attempt to make it more profitable.The buildings in that part have no relation with the waterfront as they are partially cut off from it by a main road.

Office buildings The most recent expansion in the area, these buildings have been built in new landfills. Even if the area is in a considered safe level the buildings and the landfill have been built with some artifices to deal with water risk.The first level of some buildings is on stilts and in others the first level is occupied only by parking garage.

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Spatial analysis Layers / topography 1 2 3 4

Landscape Occupation Network Topography

Tipology 1 - Rotterdam Heijplaat FSI 0,15 GSI 0,20 OSR 4,11 L 1,34 Total footprint 1,100,102 m² Groos floor area 1,483,729 m² Number of dwellings 9.891,52

Tipology 2 - Amsterdam Java Island FSI 2,0 GSI 0,40 OSR 0,32 L 6 Total footprint 2,719,697 m²

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Groos floor area 14,413,376 m² Number of dwellings 96.090

Tipology 3 - Barcelona Eixample FSI 3,0 GSI 0,60 OSR 0,12 L 5 Total footprint 4,308.733 m² Groos floor area 21,620.064 m² Number of dwellings 144.133

Spatial analysis Built capacity / density

Spatial analysis Quay construction types

Caisson blocks

Docks and quays around Heijplaat have been gradually dug and built using diverse techniques. Waalhaven is the largest port area in the world that was manually dug.

There are several types of quay construction in the area; however most of the 42 kilometres of quay of the area are of three main types, Caisson concrete blocks, concrete walls or rocky taludes.

In some areas there are successive layers of quays, for example where original caisson blocks quay has been reinforced by a new wall of concrete or metal.

Caisson block - Meerhaven source - ir. J.G. de Gijt

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Technical drawing of quay construction in Waalhaven Aerial photo RAF - Heijplaat 22-march-1945 source - www.watwaswaar.nl

source - Archives of Rotterdam Municipality

Concrete / metal wall

Rocky talude

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Technical drawings of quay construction in Stadshaven source - Archives of Rotterdam Municipality

Port x City Dock Scale

Leuvenhaven 1604

Kop van Zuid 1890

Meerhaven 1920

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Waalhaven 1955

Eemshaven 1970

Maasvlakte 2 2013

City & River Connections and scale

London River Lenght Number of bridges River widht

29 km 18 250 m

Paris River Lenght Number of bridges River widht

26 km 44 185 m

Rotterdam River Lenght Number of bridges River widht

39 km 5 350 m

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Former port renovations International comparison

Barcelona The renovation of Barcelona former harbour is part of the strategic plan prepared for the city in the 80´s. The investments trigged by the 1994 Olympic Games gave an extra push on the area renovation.

The renewal included a new passenger’s terminal, a commercial centre and a marina. One remarkable feature of Barcelona´s case is the location of the area of intervention, just in front of the main axis of the historical city, the Rambla.

Another aspect worthy mention is that some of the port activities are still in place.

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Buenos Aires The area of Porto Madero is a notorious example of port renovation. That area of the port was used to house port activities for a brief period. The design of the docks, 4 spaces connected by sluices was soon obsolete due to the increasing size of ships. The area was renovated in a public private partnership and has drastic changed the urban setting in the immediate surroundings.

The historic warehouses and the quays are the anchor of the place and vacant plots in the house now new constructions.

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Former port renovations International comparison

Cape Town Victoria and Alfred Waterfront is the main commercial and leisure destination in Cape Town, annual figures are around 22 million visitors. The area was renovated after claims from the city citizens, and like in Barcelona new functions share the area with remaining port activities.

The program includes housing, commerce, leisure and office space, the existing buildings have been intensively used.

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Hamburg Haffen City claims to be the largest urban renewal under construction in Europe. The area just in front of Hamburg historic centre is a showcase of solutions regarding measures to deal with water threats.

A series of design solutions can be found here, partially as a result of tidal variations of up to 6 meters and safety regulations.

The presence of the active port is here not a factor to prevent new functions, on the contrary, the sight of ships and port is considered an important commercial atractor.

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Conclusion of the analysis

Several aspects have been found relevant in the analysis of Heijplaat and can play a prominent role as design guidelines, these historical, typological or quantitative aspects and the observation of previous interventions in port areas have build up an initial framework that will be observed in the project.

Connections There is a lack of connections between both banks of the Nieuwe Maas, a quick review of cities developed along rivers shows the crucial role of connections across the water. Evidently the Maas is not of the same scale and width of other urban rivers, but the number of connections is definitely one of the reasons for the sharp contrast observed in social and economic aspects on the two sides of the city.

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The problem with connectivity is not only related to both sides of the river, the almost 14 km of quays and docks creates a considerable distance inside the area, and some parts of the site are more related to the centre of Rotterdam because than to the neighbouring areas.

Public transportation is also not sufficient; the area is served by two lines of bus and one water bus line. The metro line passes at the border of the area, just behind the commercial zone. There are also several train tracks in the area that are only partially been used for cargo and that can be converted in the future into tram lines.

Local traffic and heavy cargo coexist in the local road system, but the infrastructure is well designed in order to avoid further problems.

Water Safety The area, despite the fact that is situated outside of the dike ring, is relatively safe considering the current risks, only a few parts have the risk of flood in an event of 1:100 years risk rate. Most of the area is above 3.00 NAP which is a good standard for now but can be not enough when some of the future scenarios for water level are taken into account. One other relevant aspect is related to the fact that most of the area is paved and therefore can be a problem in an event of intense rain fall.

The strategy for the area must allow that some parts that are no longer used by the port could be used to implement new functions, the international cases of port renovations shows that to a certain degree this proximity with a working port can be beneficial for the region.

Other point observed in the other cases of renovations is that it is crucial to establish a direct connection from the area to be developed with the formal city, in the present case it will be not so straight forward like in Hamburg or Barcelona where the limits between port and city where just a line. Rotterdam port evolved using the gaps in the urban fabric but there is hardly any direct visual connection from the city to the port, the height difference and the dike ring are mainly responsible for that.

The project will have to deal with the direct connection with the city fabric and as well to come up with visual guidelines, creating a system of views similar to what was planned in Rotterdam centre and named ‘window on the river’.

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Land Use Heijplaat was conceived to house people that worked in the port that is no longer what can be observed now, the region is under a process of emptiness and some actions have been taken to revert such process. Is also a fact that even with the construction of Maasvlakte 2 some of the port activities will remain on the site for a while.

How to deal with the port as a neighbour for a bit longer is one important point to be observed in the project.

Spatial Framework

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Road Network

Visual axis - pedestrian / bike connections

Green Corridors

Public Transport system

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Projects

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Green Bridges

2013

2014

2020 - 2060

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2013

2014

2020 - 2060

Heijplaat Beach

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Some of the quays in the Stadshaven have been built using the caisson technique.This type of construction uses pre-cast concrete modules that are produced in a dry dock and later transported by boats to the site. The modules are composed by a hollow grid that would be filled with sand once the parts were assembled; the parts were disposed leaving a gap between them that would later be filled with other parts.

2013

In the solution proposed here one of the starting points was to avoid the extra cost involved in removing the caisson blocks. At the same time the design solution aims to take advantage of these structures.

2014

An example of how this type of quay can be reshaped was found in Recife, Brazil. Caisson quays were used in the expansion of Recife´s port, however a part of that work was left unfinished. What resulted was that a tidal lagoon appeared in the space that should have been filled with sand. After 50 years the banks have been shaped by the sea and assumed a more natural aspect.

2020

In this proposal the quays will be lowered in some parts and part of the sand will be excavated giving place to a tidal lake, the sand removed can be used to highten the ground level. In the future more sand provinient from port dredging can be added creating a safe level even in the event of higher water levels.

2060

Recife - Brazil source: Google Maps

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Sculpting Terrain Mrudhula Koshy

Sculpting Terrain Mrudhula Koshy

The last location in the regional strategy is the island of Dordrecht.

Inspite of being bounded by rivers on all sides, this city does not use the existing water networks to potential. The proposed transformation intends to bring back the relation which the city used to have with water.. This is tested in the south of Dordrecht by means of estuary restoration, creek widening and mounds by sedimentation.

The transformation intends to restore ecological benefits to the region. It proposes three diverse environments,. One is a relatively safe area, the second is subject to controlled flooding and the third aea is eventually transformed into an extension of Biesbosch and contributes to ‘Room for the river’.

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The ensuing urbanization also is with appropriate typologies and densities. It looks at re - distribution of urbanization to redue the urbanization in the north of the island. The island is eventually transformed into a resilient delta city by sculpting and moulding the terrain over 75 years.

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Evolution of the south of dordrecht into a resilient environemnt with various spatial typologies

Dordrecht The Isle of Dordrecht (Eiland van Dordt) is formed by the Beneden Meerwede and the Oude Maas in the North, the Nieuwe Meerwede in the South and the Dordtsche Kil in the West. Another significant water is the Wantij which divides the island into a Western and an Eastern part. The island covers about 10,000 ha and most of the Western part consists of dike ring 22. Basically only part of the Nature Park Biesbosch in the South of the island and the historical center of the city of Dordrecht in the North are situated outside the dikes.

Urbanisation along the river Merwede – Old Meuse

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The river Merwede was most probably a narrow and shallow river during the Roman period and of limited importance for navigation (Hoog de, 1987). Due to several floods, like the flood in 1150, the river Merwede became better navigable and urban areas were founded along the river. The city of Dordrecht was founded on a small branch of the river Merwede and on the northern bank of the river Merwede the village Zwijndrecht was founded.

The inhabitants of Zwijndrecht mainly lived from fishing industry at first, but later on they mainly lived from agriculture and after that from horticulture. The change from agriculture to horticulture was the result of the construction of dikes which protected the city against floods but made natural irrigation impossible (Municipality of Zwijndrecht, 2008). In the second half of the thirteenth century the river courses in the region of Zwijndrecht and Dordrecht changed drastically.

At the city of Heusden the river Meuse was dammed. As both rivers, the river Meuse and the river Merwede, were connected this measure caused a higher discharge on the Rhine branch Merwede (Herwaarden van, Boer de et al., 1996). This measure eventually

resulted in the creation of an extra river course: the river Old Meuse between the city of Zwijndrecht and the city of Dordrecht. Before the disastrous St.-Elisabeth flood of 1421 the cities Zwijndrecht and Dordrecht were connected during low discharges and low tide and were separated during high discharges and high tide. Hence it was possible to cross the tidal trench (Municipality of Zwijndrecht, 2008).

Due to St.-Elisabeth flood this setting changed; the river Waal and Merwede got a higher discharge and the river IJssel a lower discharge which caused silting up of the IJssel in the following years. Cities like Dordrecht took advantage of this development and became prosperous trade cities. The markets of Dordrecht gave the inhabitants of Zwijndrecht the opportunity to sell their products and the horticultural activities expanded rapidly.

Since the nineteenth century, the industry flourished in cities like Dordrecht and Zwijndrecht and the industrial revolution intensified this development. Around 1900, several chemical plants and a rice company came to the city of Zwijndrecht. These factories were mainly constructed along the river outside the dike whereas the construction of new living districts happened within the dikes in the polder (Visscher, 1998). The location for industries along the river was ideal for transportation. Additionally, this development shows that the municipalities had less interest at that time in using the urban riverfront as an urban quality in their city planning. In the twentieth century, especially in the second half, the industry was less flourishing in Zwijndrecht.

Cities like Rotterdam grew tremendously and attracted many companies. Many industrial areas along the river Old Meuse became abandoned. Nowadays, there is the tendency for river cities to embrace water in their urban development plans. For instance harbour areas are re-developed into new residential areas, such as in Dordrecht (Hooimeijer, Meyer et al., 2005).

Highway ad Railway

Primary and secondary dike

urbanised areas

Farmlands

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Wetlands

Water networks

Layers of the island of Dordrecht

The city of Dordrecht along the river Merwede The city of Dordrecht was not founded along the river Merwede, but along the creek Turedri(c)ht. This creek was connected with the river Dubbel and the river Merwede and turned into an important stream due to the floods around 1150. This event made the count Dirk VI van Holland decide to found the city of Dordrecht on both riverbanks of the creek Turedri(c)ht (Hoog de, 1987). This location was perfect to stimulate navigation in both north-south and east-west direction. Goal was to turn Dordrecht into a successful trade city. Already around 1250 this goal was achieved; Dordrecht became the most important city of the region of Holland. At that time the city had a population of only 5,000 inhabitants, but this number was doubled within a hundred years.

Dordrecht was the first city in which the tax system was implemented and it received more privileges in 1284 (Herwaarden van, Boer de, et al., 1996). Products like wood, salt and oat, which were supplied along the river Merwede or river Lek had to be sold at the market of Dordrecht. In 1338 same regulation became operational for the river Meuse. Dordrecht became the mercantile city of the Golden Century with a lot of warehouses. In 1655 the harbour area of Dordrecht got its final shape. Nowadays the harbours are mainly used for small-scale pleasure boats so unload of products is rarely seen.

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In the seventeenth century, Rotterdam and Amsterdam became the main trade centres of the Dutch Republic, but Dordrecht remained an important trade centre for especially inland navigation (Frijhoff, Nusteling, et al.,1996). One of the reasons was that the harbour of Dordrecht was not accessible for large sea vessels due to the limited water depth. Besides the strong trade position, the city of Dordrecht became a regional market for agricultural products around 1740. This lasted until the industrial revolution. During the industrial revolution Dordrecht changed from a trading city into an industrial city and Rotterdam developed itself into an all-round harbour city. In the Twenty-First Century, the city centre of Dordrecht developed into an important shopping area and nowadays it fulfils a social economic function on a regional level.

Due to the easy connection of the city centre by car and train, the river side was neglected and the heart of Dordrecht moved more inland. However, this shift has been partly undone due to the reintroduction of the ferry. Also in the northern part of the city a shift towards rediscovering of water is seen. This area, called Stadswerven, used to be an industrial site and is currently redeveloped into an area were people can live, work, and relax.

Urban flood control along the river Merwede – Old Meuse Along the river Merwede – Old Meuse, the city of Dordrecht and the city of Zwijndrecht are investigated on the development of urban flood control and their current FR measures. Both cities experience tidal influence of the North Sea, so both storm surge and fluvial floods are a danger. This is different from the other Dutch Rhine branches.

Dordrecht protected by sand dunes Dordrecht was founded on both sides of the riverbanks of the creek called Turedri(c)ht. As the settlement grew, better protection against fluvial floods became important so the river banks were heightened and transformed into dikes. In the thirteenth century, the area between these dikes and the river Merwede - Old Meuse mainly contained a marshy area with sand banks. In 1410 the first expansion towards the river was made by constructing a harbour; more expansions were carried out in the following years. These harbours were and still are unprotected against floods. Around 1917 the dike needed heightening, but this was easier said than done.

By then, many houses were built on both sides of the dike and the crest was used as an important shopping street of the city. Stop logs in doorways and alleys were used for achieving a sufficient height.

Unfortunately, the improved housing fronts could not resist the disastrous flood of 1953. Sheet piles were added and the houses were strengthened with extra concrete walls. The doorways and alleys remained closed by stop logs during flood conditions. These stop logs were stored in these houses. Unfortunately, local residents had used them for timber wood or for fire wood. This is why the water board organises a simulation of a flood event every year. It keeps the awareness amongst the residents alive. During the last decades the river discharge has increased and the sea level has risen.

The consequence was that the flood defence in the city of Dordrecht needed further improvement. Since the nineteen seventies many committees were challenged to find a solution to this problem. The city centre is listed as monumental so it is impossible to heighten and widen the existing dike. The solution to the threat of storm surges was sought in the construction of a storm surge barrier that was completed in 1996. The storm surge barrier reduces the water levels during storm surge conditions. A solution for the increasing flood discharge on the river Merwede – Old Meuse has not been found yet.

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Figure showing the ensuing lost relation of the city with water upon further urbanization

Interaction along the river Merwede – Old Meuse: Dordrecht Year 1300

Year 1600

The navigability of the river was the main motive for the foundation of the city of Dordrecht. The city was founded on both sides of the riverbanks of the creek called Turedri(c)ht. So, landscape features that could provide flood protection were used in the choice in where to found settlements. The river Merwede – Old Meuse gave the city the opportunity to turn into a successful trade city. As the settlement grew, better protection against fluvial floods became important so the river banks were heightened and transformed into dikes. In the period of 1540 – 1655 harbours were dug outside the flood defence. Remarkable is that the city of Dordrecht is one of few trading cities that has always been protected against floods by dikes and not by city walls. Since the twentieth century the harbour areas have been transformed into living districts; until today these areas are not protected against fluvial floods. The urban activities have left no space for FR structures. The result is that people have to endure floods every few years. The main flood defence faces a challenging problem. Many houses were built on both sides of the dike and the crest was used as a shopping street which did not leave any space for improvement of the flood defence. Compromises are made to protect the hinterland against floods to a certain amount while respecting the urban activities adjacent to the flood defence.

Criticism

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Year 1900

The interaction between the city and water has been reduced to specific urban spots unlike the city centre. The spatial coherence evident in the city centre is absent in the rest of the city. In the urban development of the rest of the city, the avoidance of conflict among the functions led to a homogeneous urbanization that is indifferent to the dynamics and challenges that the river can offer. The little variation in internal build up has led to spatial incoherence. The existing main infrastructure does not cater equally to all parts of the island. The water networks are also not used to potential.

Expansion Scenario

Evolution of the city centre of Dordrecht showing the strong relationship of the city centre with water

The urban consolidation of the island is bordered by the wetlands on the east and farmlands on the south. The east has potential to become a recreational zone combining varied living environments in water. The south has potential for urban shuffling to reduce the high density in the north. This area can be fragmented by means of creek restoration and artificial sedimentation to create mounds. Further expansion will consider a long term transformation of the island to prevent monotony of functions.

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Historical evolution of the city of Dordrecht. Source: Delta Programme, Rhine - Meuse delta

Experiencing cultural landscape, living in the polders and farmlands as opposed to the urban areas

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Landscape living, with building typologies of lesser density and varied spatial environment

Cross - section showing drain, retain and store

Estuary restoration to enable water transport

Heightening of ground by artificial sedimentation

Dwelling on mounds

Estuary restoration for ecological benifit

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Approach The new approach for river city interaction would be a long term transformation by fragmentation of the island by creating mounds and restoring the creeks. This enables the creation of a diverse urban environment, one where people adapt to living in water.

Reason for Approach The reason for adopting a resilient soft approach were many. People do not have to live with the fear of evacuation several times a year or leaving their homes and starting all over again in flood free areas.

Also, the cost of maintenance, improvement and construction of flood retaining structures and and conversion of flood endangered areas into flood resilient areas for a period of 100 years are lower than that of migration to flood free areas. Estuary restoration also brings ecological benefit to the area. It enables the testing of various types of dwellings depending on the flooding situation.

It is a shift away from conventional urbanised areas and facilitates experiencing the cultural landscape.It enables living in wetlands and marshes. It enables a co-existence and integration of functions.

Reference Case study Hafencity (Hamburg, Germany)

FIGURES: Borough: Hamburg-Mitte 98District: Hafencity Founded: 1997 Population: 1428 (in 2011) Area: 157 ha Location: Elbe river island River: Elbe Height: 8 meters above sea level Public investment ca. € 2,4 billion Private investment: € 8,0 billion Number of new jobs: 45000 Number of completed projects: 51 Number of planed or under construction projects: 35 Gross floor area new buildings: 2.32 million m2 New dockside promenade: 10,5 km Number of new housholds: 6000

The German city of Hamburg is situated about 110 kilometres from the mouth of the river Elbe. The city has developed itself between the river Elbe and the reservoir of the Alster. Only a small part of the city is threatened by floods, but this lower part can be inundated within six hours. This area is protected by dikes and quay walls. Since 1990, a height of nine meters above the German water level standard is obliged for flood defences in the area of Hamburg. Unfortunately, the former harbour areas did not reach this protection level. At this moment, these former harbour areas are transformed by implementing the redevelopment project called ‘HafenCity’. The harbour islands have a surface of 150 hectares which could create a large extension of the current city centre. Goal is to develop large amounts of residential blocks combined with offices and tourist attractions. This redevelopment is allowed under the condition that improvement of the flood defence is incorporated.

Conventional methods like heightening of the dike or quay are not feasible due to lack of space and the restricted strength of the foundation of the existing quay. That is why another strategy is applied that implies the combination of heightening of the quays and singular protection measures. The existing quays are given a second life. The singular protection measures are obligatory for every building that is built outside the flood defence system. Every ground floor which is located below the level of nine meters above German water level

standard, needs to be constructed as waterproof. Windows need to withstand the high water pressure and steel shutters, which need human action to provide safety against floods, have to prevent damage on the glass windows that could be caused by floating debris. The function living is prohibited on the ground floor. In the project ‘HafenCity’ the ground floors are used for car parks, restaurants and offices. The residential blocks have different access levels. Along the waterfront the original height is preserved which keeps contact to the harbour water. The entrances to the blocks on the other side are on a higher level. The ground floor of these blocks is waterproof and is part of the flood defence.

Escape routes are also important in the ‘HafenCity’ project because the region is not heightened entirely. Roads and bridges are constructed on different heights, so an escape route is always guaranteed.

This realised project shows that the integration of urban functions and flood protection is possible if extra measures, such as escape routes, additional legislation on for instance allowed activities on ground level, are taken and formulated. It shows that such multifunctional structures are feasible in a transition zone water – earth that has fluctuating water levels. The uncertainties that are caused by climate change are also taken into account. The waterproof housing front and the escape routes on different heights can cope with increasing water levels.

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Sentum utescivere cludem inumena, oc, Cateraectu misquam auspimm orituam vignost a nim pribus omnissi lintrate ternict orudem conimih illestemus

Pole Dwelling

Floating Dwelling

Shift in living environment

Green networks

Co - existence of different environemnts

Hollow dike dwelling

Safe living environment

Mound dwelling

Existing dike line

Proposed restructured dike line

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Delta urbanism toolbox

Blue network

Expansion scenario

Aim of the project

Water as a tool and design principle for shaping land. This will lend more identity to the delta landscape and also provide storage and detention purposes in case of rainfall and water level rise.

• Safe Living environment: Hard and Soft measures • Estuary restoration and foreshore tidal wetland for ecological benefits • Experiencing cultural landscape: Creek restoration and polder landscape. This is essential to counter the effects of climate change in water management in The Netherlands. Water retention is most convenient in existing grassland since it is close to the creeks and farmlands.

• Penetration : Living in water. A unique landscape can be generated with different typologies for a coherent urban and landscape network.

The existing compact urban expansion is transformed via fragmentation of the island and lead to different living environments.

This would lead to a dense network of water courses with maximum number of dwellings with direct contact with water. River basins and canals create a base where other developments can be positioned.

The Southern part of the delta is transformed into an area where people would be accustomed to living with water. This would be done by restoring a part of the natural conditions and exploiting the opportunities this would offer to redefine the relationship between natural and urban dynamics. It would result in an alternative urbanised area.

Areas between the polders are returned to the river streams.

Natural processes like sedimentation and natural vegetation are enhanced.

The water dynamics, polder structure and tidal landscape form basis for a resilient interactive city. With a timeline of 100 years, the rigid structure is transformed into a naturally integrated one.

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Figure showing existing segregation between the city, port, farmlands, wetlands and water networks

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Figure showing proposed transformation of Dordrecht by integrating of functions and elements

Map showing the proposed area for transformation

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EXISTING PHASE

The map on the right documents the existing canals, creeks, ditches and streams. The historical process of reclamation and draingae lead to extensive poldering which shifted away from the natural process.

The existing primary dike forms a hard border which cuts off the relation of the city with the water. Te secondary dike divided the city into the urban north and natural south. The transformation calls for a more integrated Dordrecht where the environments would follow a more nuanced urbanization with varying densities.

The Bovenpolder is geographically positioned north of the southern part of Dordrecht. This enables it to be transformed into a safe evacuation high ground zone which will get flooded only once in 2000 years. The Zuidpunt polder can make use of the existing defence to create a medium density controlled flooding zone.

De biesbosch polder which used to be part of the Biesbosch can be returned to nature to make room for the river. This area would have minimal urbanization. It would be characterised by floating or amphibious houses adapted to gearing with flooding. The intensity of flood may vary from once every year to once in 10 years.

104 Existing urban area

BovenPolder

Nieuwe Merwede

SECTION A -A

Existing Infrastructure lines

SECTION Existing urban area

De Zuidpunt polder

Primary dike

C-C

De Biesbosch Polder

Nieuwe Merwede

BovenPolder

Nieuwe Merwede

+ 1.5 +0

Vierpolders

Bovenpolders

Secondary Dike

Buitenpolder

Primary dike

De Biesbosch Polder

Nieuwe Merwede

SECTION B-B Existing Infrastructure lines

De Zuidpunt polder

Primary dike

De Biesbosch Polder

Nieuwe Merwede

Map showing existing dikes, ppolders and creeks

B

A Bovenpolder

A Buiten polder

+ 1.5 +0

De biesbosch polder

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C Zuidpunt polder

B

+ 1.5 +0

LEGEND

+0

Existing railway line Existing creeks Existing secondary dike

e

e

C

Wetlands and marshes Existing ditches Existing highway Existing primary dike Polder divisions

+0

+0

PHASE 2

To initiate the gradual transformation, the creeks and canals which have potential to be widened are identified. In de Biesbosch polder, current moulding of terrian used to be under the influence of the sea.

Transformation is accelerated by breaching the dike.

existing infrastructure lines which are to be the new primary dike are to be raised. Green boulevards are introduced on the infrastructure line and the actualmlines are carried underneath to enhance the slow networks in the city.

By simultaenoulsy widening the exisitng streams, the natural transformation is enhanced. In the Zuidpunt polder, to enable a controlled flooding situation, sluices are introduced in the primary dike. The

To enable the formation of the safe zone in the Bovenpolder, mounds are deposited by artificial sedimentation. The material obtained from widening the canals is used for the purpose.

Existing urban area

BovenPolder

Existing Infrastructure lines

De Zuidpunt polder

106

Primary dike

Existing urban area

Nieuwe Merwede

De Biesbosch Polder

Nieuwe Merwede

BovenPolder

Nieuwe Merwede

SECTION A -A

+ 1.5 +0

Vierpolders

Bovenpolders

Secondary Dike

Existing Infrastructure lines

Buitenpolder

De Zuidpunt polder

Primary dike

De Biesbosch Polder

Primary dike

Nieuwe Merwede

De Biesbosch Polder

Nieuwe Merwede

SECTION C-C Existing urban area

BovenPolder - Heightening the ground

Nieuwe Merwede

+0

Vierpolders

Bovenpolders

Secondary Dike

Buitenpolder

Primary dike

De Biesbosch Polder

Nieuwe Merwede

SECTION B-B

Green boulevard above new primary dike

De Zuidpunt polder

Primary dike

De Biesbosch Polder

Nieuwe Merwede

Phase 2 showing the creeks which are to be widened and breaks in primary dike

+ 1.5 +0

B

A

A

+ 1.5 +0

+0

e

107

C

B

+0

LEGEND

+0

Green Boulevard over Infrastructure dike

e

e

C

Widened Creeks Existing secondary dike to be raised Wetlands and marshes Area to be raised Existing creeks & ditches Rainwater retention basins

+ 0 (once in 2000 years) + 3.4 + 2.4 (one time a year) + 1.3 (average high water level) +0

Existing primary dike Polder divisions Sluices in dike

Existing urban PHASE area

BovenPolder

3

Existing Infrastructure lines Existing urban area

Nieuwe Merwede

Most of the transformation is done on existing farmlands. To compensate for this, farms of various scales are introduced in the three areas.

Farming in the city, and community farms are enhanced. De biesbosch polder is depoldered through a gradual transformation. This means it will be subject to frequent floods. So crops and biomass which thrives even during floods can be farmed there.

The widening also means the water bus network which currently connects the shores of Dordrecht, Papendrecht and Zwijndrecht can be extended throught the restructured south of Dordrecht as well.

This is to enhance slow network accessibility of the south. Material is taken out from the area and used to heighten the mounds in the Bovenpolder.

There is also potential for fish and algae farms in the newly restructuredDede Biesbosch polder. There is also the need to restore the estuPrimary Zuidpunt polder dike BovenPolder ary running through de Biesbosch polder. The widening of the estuary has multifold advantages. It enhances ecological benefits.

The Bovenpolder eventually reaches a height of 3.4 m so it would be very safe and subjectPolder to floods only once every 2000 years. Natural De Biesbosch processes will transform de Biesbosch polder into a naturally resilient area.

Nieuwe Merwede Nieuwe Merwede

+ 1.5 +0

Vierpolders

Bovenpolders

Secondary Dike

Existing Infrastructure lines

Buitenpolder

Primary dike

De Biesbosch Polder

De Zuidpunt polder

Primary dike

Existing urban area

Nieuwe Merwede

De Biesbosch Polder

Nieuwe Merwede

BovenPolder - Heightening the ground

Nieuwe Merwede

108

SECTION A -A

+0

Vierpolders

Bovenpolders

Secondary Dike

Green boulevard above new primary dike Existing urban SECTION C-C Rainwater area Mounds

Buitenpolder

De Zuidpunt polder Mounds

storage

Primary dike

De Biesbosch Polder

Community farms

Primary dike Mounds

Nieuwe Merwede

De Biesbosch Polder

Nieuwe Merwede Nieuwe Merwede

BovenPolder Mounds

Rainwater retention

Mounds

Rainwater retention Community farms

Mounds

+0

Vierpolders

Bovenpolders

Secondary Dike

Buitenpolder

Primary dike

De Biesbosch Polder

Nieuwe Merwede

SECTION B-B

Existing Infrastructure lines Green boulevard above new primary dike

De Zuidpunt polder Living in pastures and meadows

Primary dike Restructured primary dike

De Biesbosch Polder Widened creek Water bus route

Nieuwe Merwede

Phase 3 showing transformation of farmland into wetland, infrastructure line as dike and raised mounds

B

A

+ 1.5 +0 +0

A

e

+0 +0

e

109

C + 3.4 (once in 2000 years) + 2.4 (one time a year) + 1.3 (average high water level) +0 +0

B LEGEND Green Boulevard over Infrastructure dike

e

e

C

Widened Creeks Mounds as evacuation ground Cutting from ground

+ 3.4 (once in 2000 years) + 2.4 (one time a year) + 1.3 (average high) +0

Wetlands and marshes Area to be raised Existing creeks & ditches Rainwater retention basins Mounds in meadows Proposed primary dike

PHASE 4 Existing urban area

BovenPolder

Nieuwe Merwede

LIVING ON MOUNDS Room for the river in combination with working with nature is used for the transformation of Dordrecht.

The intended transformations only showcase possible ad potential outcomes. The actual spatial outcome is uncertain. It is intended for the water system to have a clear functional task to counter water nuisance now and in the future.

Controlled flooding conditions would be initiated in the northern BovenPolder inner city. Tidal landscapes would demarcate the southern part of the island. The south and eastern part of the island would be more natural.

In this way, the flood endangered areas would be transformed into

Existing urban area

110

Existing urban area

flood resilient areas.

The section below shows the desired transformation of Bovenpolder.

Mounds of various levels are established. Since the ground is relatively safe, the urbanisation here can be dense. Mixed use facilities and mid - rise buildings form the urban typology here. The valleys that are formed as a result of the transformation are used as retention for rainwater basins.

Community gardens and farms are enhanced for localised farming. Living on the mounds means a safe area which doubles up as evacuation zone in case of high floods. This area relates to the water by means of terraces leading to the wetlands and marshes. IThe buildings also have balconies which overlook the area.

BovenPolder - Heightening the ground

Nieuwe Merwede

Nieuwe Merwede

SECTION A -A

Existing urban area

BovenPolder Mounds

Rainwater storage

Mounds

Community farms

Mounds

Mounds

Nieuwe Merwede Rainwater retention

Mounds

Rainwater retention Community farms

Mounds

Phase 4 showing urbanisation of three diverse environments with appropriate typologies

+0

B

A

A

+0

111

C + 3.4 (once in 2000 years) + 2.4 (one time a year) + 1.3 (average high water level) +0

B LEGEND Green Boulevard over Infrastructure dike

C

Widened Creeks Mounds as evacuation ground Wetlands and marshes Existing creeks & ditches Rainwater retention basins Mounds in meadows Proposed primary dike Proposed water bus route

112

Image showing converted mounds and ensuing urbanization, the area overlooks the proposed wetlands

113

+0

PHASE 4

Vierpolders

Bovenpolders

Secondary Dike

Buitenpolder

LiIVING IN WETLANDS AND MARSHES

De Biesbosch Polder

This area is subject to floods in frequent intermissions. This forms the terrian of the area. The restored estuary enhances the ecological aspect. It provides an additional route for the water bus.

Aquaculture by means of biomass in introduced. Fish and algae farms are also new means of wetlands farming. This area is reached through gradual levels from the mounds.

Vierpolders

Bovenpolders

Secondary Dike

The transition area between the mounds and wetlands is envisaged as the buffer zone. This buffer zone is multi - functional. It has recreational zones on various levels. Promenades which connect to the water Buitenpolder the relation of the city with the water.

De Biesbosch Polder establishes

Primary dike

Existing Infrastructure lines Nieuwe Merwede

Certain areas which are subject to floods only once in every 10 years can be used as grazing gounds or for fruit orchards. The heightened mounds also provides space below for parking thereby effectively utilising the levels.

The building typology in the wetlands are characterised by dwelling on poles and amphibious housing. People living here would be adapted to the idea of floods and would be prepared for it. It enables living in nature and close to it.

+0

Since the area would be subject to tidal influences, living here would Existing Infrastructure lines mean being witness to various fluctuating and ever - changing landPrimary Nieuwe Merwede dike scapes.

The primary dike is longer a hard barrier or defence line.

+ 3.4 (once in 2000 years) + 2.4 (once a year) + 1.3 (avg high) +0

114 Vierpolders

Secondary Bovenpolders Buitenpolder Dike Heightened mounds P + R Crop Public terraces Algae/Fish lands farms

Aquaculture/ Biomass

De Biesbosch Polder Widened creek

Living in marshes and wetlands

Primary dike Restructured primary dike

Green boulevard above new primary Nieuwe Merwede

SECTION B-B

Existing Infrastructure lines Green boulevard above new primary

+ 1.5 +0

De Zuidpunt polder

Primary dike

De Biesbosch Polder

LIVING IN PASTURES AND MEADOWS This area is charcterised by a mid - way between the mounds and the wetlands. The Zuidpunt polder is subject to controlled flooding. The widened canals and creeks form the spine for decing the course of urbanization here.

It is composed of medium density low rise buildings. Neighbourhoods arranged in clusters around the waterways form the primary typology.

This area co- exists with the farms and croplands. The experience enables a return to living in the countryside.

De Zuidpunt polder

Primary dike

Nieuwe Merwede

environment. It also means that it can alleviate the density in the north of the city by distributing the urbanization. The new areas provide the means to restructure the north in a similar manner. Neighbourhoods which need improvement can be restrutured using similar pronciples.

The focus would be brought back to the water and the ensuing urbanization would be oriented with respect to water.

The green boulevards also helps slow down urbanization. The whole process can be characrterised by speeding up the process in the south and slowing down in the north.

In this way, the island of Dordrecht is transformed to a delta city De Biesbosch Polder Nieuwe Merwede gradually through natural and non - natural methods by 75 years.

+0

The three restructured areas thus provide a diverse alternate urban

+0

115 dike

De Zuidpunt polder

Primary dike

De Biesbosch Polder

Nieuwe Merwede

+ 3.4 (once in 2000 years) + 2.4 (one time a year) + 1.3 (average high) +0

dike

De Zuidpunt polder Living in pastures and meadows

Primary dike Restructured primary dike

De Biesbosch Polder Widened creek Water bus route

Nieuwe Merwede

SECTION C-C

116

117

Image showing converted wetlands, fish farms and floating dwellings

118

119

Image showing living in pastures and meadows, dwellings alongside farmlands

EMU spring semester 2013 TUDelft