Finalists

_{Think, before settling down}

_{Bangladesh, Dhaka, Kamrangirchar, along the Buriganga river… in close future, a fringe of land where dwellings have been swept away. With increasing frequency and intensity of storms and floods , most inhabitants definitely left this area, instead of coming back once water level was back to "normal". They progressively tried to reach more secured spaces, though Dhaka is already overcrowded as it concentrates – at least in emigrants minds – most economical opportunities in this agricultural country.
Newcomers kept trying to settle down, during the dry season, but the red sails network that now spreads over the borders of this dangerous area notifies they would better find their way around the green sails. Stressed by cables linking masts, these reused tarpaulins, sheets and actual sails look explicit enough with their colour code, but neighbours are still here to confirm and relate previous disasters.
Monsoon ambiguously became a regular deadly phenomenon as much as a yearly blessing, adding risks to the constantly raising water level.
The coloured beaconing evolves, depending on the expansion of the city, floods, climate change, etc.
Nevertheless apparent leftover spaces are not sterile stigmas, they become social, economical and ecological places for the neighbourhood. Taking advantage of the agricultural knowledge of many inhabitants, they gradually transformed to cultivated fields and gardens that can directly benefit to the poor urban population living next to them.
But these fields also ensure better infiltration of flood water and stabilisation of this exposed soil. They create new resources, usually far from the city and its massive food needs, and offer another chance for slum dwellers to be sustainably involved in economical life.}

_{Tank, meanwhile ...
Chronic drought, insufficient water supply in Dhaka, increasing salinity of deep soils and arsenic pollution of Bangladeshi groundwaters are other reasons to implement this project. The network is not a mere didactic beaconing, the strange artificial trees formed by the sails and masts indicate flood risks but also capture and store rainwater.
This water, far less contaminated than Buriganga river and abundant during extended monsoon season , hits the spread sails and pours through the mast, acting like a simple gutter. Then water falls on a large sand filter to slowly get cleaned up and reach a buried concrete-tank. Such a simple mechanism can save and supply healthy water during dry season, both for domestic use and agriculture. Depending on tank capacities and network density, it could be locally seen as a long-term substitution where no water supply is available.
The whole installation can be used as a support for other light networks, such as electricity or telecommunication lines, towards isolated neighbourhoods.
The first "think tanks" are an opportunity to experiment an autonomous water management ensured and assumed by inhabitants. All this is made possible thanks to a simple and low-tech project, simple in its design, understanding, implementation (traditional construction process, available materials, recycling, etc.) and maintenance.
These interventions aim at a materialised and local approach of global climate change challenges. They are based on climatic, geographical and socio-economical specificities of Kamrangirchar and Dhaka, but they could be adapted to cities sharing main features, a fragile deltaic position and a monsoon climate where water management is an ever growing issue.}

_{INTRODUCTION TO SANTOS: Santos is a delta city satellite of the megacity São Paulo, the largest city in the southern hemisphere with 25 million people living in the metropolitan area of the city. Whilst São Paulo is located on a high plateau 700m above sea level, Santos at the river mouth is located in a low-lying basin and houses the largest trading port in Brazil. Exportation and importation through its port have made it the modern city one finds today and turned it into the indispensable outlet for the production of the powerhouse that is São Paulo. Brazil is an emerging world economy with a pioneering position on renewable energy. As the host of the Amazonian Rainforest, Brazil is the earth’s lungs. Santos as a result is an important case study of the challenges facing developing world delta cities, where the complex co-existence of the influential and the vulnerable, challenge us to consider how these cities respond to the challenges of city planning and climate change.}

_{CHARACTERISTICS AND CHALLENGES FACING SANTOS: The distinctive environment of Santos is characterised by its delta location. Santos is situated 2m above sea level where 6 rivers discharge into the Santos Estuary. The city society is like that of many Brazilian cities; characterised by disparity between wealth and poverty, and it suffers from significant problems of pollution of the waterways. Slums, known as favelas, occupy the banks of some rivers as well as on the hillside perimeter of the city, where land prices are low and land is unoccupied. Some dwellers of the favelas are located in areas of high risk where sea-level rises will undermine the river bank and heavy tropical rainfall will affect the hillside stability. The solution proposes building quality housing designed to function in the context of increasing flooding events, which would assist any civic slum clearance strategy. These communities would also be developed with the need for employment and amenity that currently is lacking in the favela. The delta city also uses its location to optimise the opportunity to generate growth and employment through the management of waste produced by São Paulo and as a world port to generate growth in world waste management industries.}

_{THE MANGROVE ECOSYSTEM UNDER THREAT: The delta’s natural ecosystem is Mangrove, and whilst much of this has been lost in Santos, remnants still remain in the north region of the island. Mangroves – the coastline guardians - are an often-neglected ecosystem acting as nurseries for fish and invertebrates, providing a refuge for wildlife, controlling water chemistry along the coast, managing coastal erosion, and serving as storm buffers. The mangroves also provide a mesh of roots where organisms that filter water dwell, including algae, barnacles, oysters, sponges, shrimps, crabs and bryozoans. The mangrove is at risk from upstream pollution from São Paulo, rising sea levels, coastal landfills, unsustainable wood harvesting, and development pressures from the city. The loss of mangrove will reduce the atmospheric CO2 sink and reduce essential oceanic carbon. As both Santos as a port and São Paulo grow these threats will increase. The solution is to build Mangrove resilience through innovation.}

_{Santos ‘Floating Mangroves’ > A climate-proof bio-engineered city: A natural challenge facing the Delta City is the effect of rising sea levels on both the natural and man-made environment. A pragmatic position is to acknowledge that in developing world cities, resilience is unlikely to be very deliverable. The vulnerabiliity of the delta to rising sea level requires that power, sanitation, transport, communications, food supply and security are also considered. Consequently, the understanding of how the mean sea level changes will change the landscape of naturally occuring deltas, can inform a holistic approach to future urban planning in Delta Cities.
Our considerations of the context of Santos has led us to assume that the rise of 1m in sea level will cause the rivers of the estuarine system to be consumed by sea, with much of the immediate floodplain to be permanently transformed into tidal lagoons. A rise of 2m would subsequently consume the remaining floodplain as it rises to the level of the city. As a result, most of the mangrove ecosystem would remain underwater for most, if not all of the time.
Bio-engineered floating mangroves are envisaged as part of a holistic solution to improve the environment and manage the unregulated growth of the city. This holistic approach to city design enables the development of a sustainable Delta City, that addresses both local and global issues. Platforms of plastic/ bouyant waste in the proposals are imported to Santos by cargo ship into the busy port as well as using the refined waste from the city of São Paulo itself. Brazil has already developed the capacity in this area of waste management. These recycled platforms from around the world will form the base of the bio-engineered city. Floating platforms will be formed from bundles of recycled plastics restrained within timber rafts. These will form a buoyant base to support a bed of silt and estuarine mud just below the water level, in turn supporting growth of new mangroves above the existing riverbed.
The existing port infrastructure supports a viable waste stream for a global problem, aiming to reduce harmful plastic pollution within the world’s oceans that has lead to environmental disasters such as the Great Pacific Garbage Patch. If the Amazon are the earth’s lungs, the delta city of Santos has the potential to pioneer waste management through the constuction of these bio-engineered cities.
The Floating Mangroves employ ancient principles reminiscent of the floating gardens of Xochimilc (Mexico), Inle (Myanmar) and Nagin (Kashmir), where communities have developed solutions that engage with water. The development of new communities that incorporate local construction materials, environmental design, rainwater collection/ filtration, and agriculture, are an ecological and current response to the issue of climate change that adopts ancient world-wide precedent as its inspiration. At a larger scale the inland plateau provides potential for hydro power generation for the wider city, while collection from hills and buildings could provide more localized opportunity with less environmental impact. The hills and cliffs could also be harnessed to support large solar arrays surrounding the city. The ‘Floating Mangroves’ will gradually replace the mangrove lost to the rising sea, whilst retaining its functions of filtering water, harbouring communities and providing storm protection to the existing city.}

_{NATURAL AND ENGINEERED DIVERSIONS STABILIZE THE DELTA LANDSCAPE:The proposal addresses the conflict of freshwater scarcity in delta cities and the abundance of fresh drainage water that is not utilized as a resource.The energy and costs for the everyday drainage activity are discussed as resource, that is not deployed to its full potential. Similar to new diversions projects in the Mississippi the fresh water can be used for many productive purposes to enhance the biodiversity in a saline environment. The workshop will explore the capacities to project this model from Louisiana onto the Dutch polders and their specific relationship to the North Sea or inner saltwater lakes.}

_{CASE STUDY ORLEANS: The geomorphology of the Mississippi Delta Fan is a product of multiple past natural diversions. Historically, the river replenished the delta with freshwater, nutrients and sediment. The “levees only” policy has resulted in channelization of the river and redirection of valuable sediment to the Gulf of Mexico. The loss of this supply of sediment and dewatering of the city results in subsidence: the delta and he city Polder are sinking into the Gulf. At the same time millions of gallons of fresh groundwater are pumped up and out of the city polder daily. This valuable flow of fresh water is discharged into the brackish water of Lake Pontchartrain without further use. Can this freshwater stream be utilized as a new productive diversion project for the delta? The engineered drainage system of the city polder provides an existing water management infrastructure that can be reinterpreted as a source of pseudo-natural river baseflow – a precious resource. How can we re-engineer the drainage and pumping infrastructure to support a new, sustainable and productive ecosystem?}

_{MULTIPLE LINES OF DEFENSE: A multiple levee line can accommodate productive bayous along the levee at a range of elevations that are fed by the drainage water. The diversified levee section provides better flood protection and supports fish farms and oyster-beds. Fresh drainage water can modulate the salinity of the basins. The constructed topography of the super levee provides opportunities to manage water flows: using elevation and gravity to facilitate movement and storage of water, controlled inundation, and management of salinity levels. The given binary “stand or fail” levee concept is expanded and widened to a “landscape super levee”. In between the levee lines are a series of ponds and bayous that convey and utilize the fresh drainage water. The “wet” levee landscape helps to control the subsidence of the structure itself by maintain saturated pore space. The Bonnet Carre spillway is a source of mineral wetlands substrate and construction materials, with particle sizes ranging from fine silts and clays to sands. Analog to the natural levee it is critical to structure the profile of the ecological diverse boundary.}

_{ECOLOGICAL DIVERSE BOUNDARY: The new landscape levee interprets the self-regulating geomorphologic principles and qualities of the delta landscape. In Louisiana this new productive landscape can compensate for some of the lost fishing grounds due to the oil spill at the shore of the Gulf of Mexico. Instead of a mono-functional technical piece of infrastructure the new super levee becomes an amenity for recreation and as well as a productive landscape. In this sense it represents an older idea of public infrastructure being a piece of civic art.}

_{Port Harcourt, Nigeria encompasses a metropolitan area approaching 5.7 million people in the Niger Delta. Our focus is on the waterfronts, the flashpoint for cyclical social and ecological tensions in the region. The delta is the hub of the Nigerian oil industry with the largest oil refining capacity in sub-Saharan Africa. This abundance of oil has attracted many multinational corporations to Port Harcourt, however, in a highly unregulated system reminiscent of the colonial past, only a fraction of that wealth is invested locally with most of the extracted petroleum is piped directly to coastal export terminals. This combination of rapid industrialization with unparalleled environmental destruction has effectively ended a rural way of life and catalyzed explosive urban growth. With an average of one oil spill a day since 1970, the devastation on the landscape ecology has placed Port Harcourt residents among the most vulnerable to rising sea levels associated with Global Warming.}

_{IDEA: Our design is a system of adaptable, floating, modular platforms supported by reused oil barrels that integrate the social and ecological functions of the cityscape into the wetlands ecosystem. In addition to modules for housing, cooking, and bathrooms, there are floating gardens which employ bio-remediative technology consisting of specifically chosen of aquatic and semi-aquatic plants to absorb heavy metals and toxins. Inspired by similar systems used on canals in Baima, China, this detox allows for a regeneration of mangrove rhizomes, the aquatic habitat which supports subsistence fishing and a fundamental part in preventing flooding and erosion. Guiding principles of our design were taken from the “Abonnema Wharf Community's Proposed Alternatives to Waterfronts Demolition”, as well as principles of mangrove ecology – the glue that binds the Niger Delta wetlands ecosystem. As a synthesis of these ecological and social principles, our design can be seen as a manifestation of Integrated Coastal Zone Management (ICZM) techniques, modeled in Bangladesh.}

_{IMPLEMENTATION: Process is a key part of the design. Floating platforms are immediately inhabitable and modularity allows for communities and extended families to remain intact. This incremental process minimizes social disruptions associated with conventional massive slum clearance . Once waterfront restoration has been completed, modules can be permanently moored closer to the shore within the mangrove corridor. A cornerstone of this wetland ecosystem, mangroves prevent erosion, provide habitat, as well as process carbon dioxide and other pollutants. Under normal conditions, mangroves respond to rising sea levels by retreating inland to a location where the water is sufficiently brackish. However, the current static, hard urbanism of Port Harcourt is incompatible with mangrove ecology and prevents the rhizomes from penetrating the urban fabric with rising salt water tides. This condition, combined with reckless oil spilling put the vital wetlands ecosystem in jeopardy. Beyond merely an architecture of compromise and coexistence, our proposal is for an urbanism of symbiosis that recognizes the importance of the mangrove rhizome as fundamental to the survival of all life in the Niger Delta. Floating module assemblages mimic mangrove ecology, and floating gardens aid in water purification. Further, corridors penetrate Port Harcourt's urban grid to allow mangrove rhizomes to reclaim space in the existing park system.}

_{CONSEQUENCES: According to the recommendations by the Abonnema Wharf Homeowners, our modular design encourages urban decentralization and economic autonomy of homeowners' and residents, while providing acceptable levels of sanitation and other amenities unseen in slum development. As cited in the Homeowner's proposal, the heavy hand of modern architecture has proven ineffective in long-term social change unless it addresses the root causes of poverty. Because the centralized, rationalist organization of the Modern city cannot not account for the dynamism of its environment, or even inhabitants, we embrace a solution of informality and flux.
Our intervention is not a panacea for the social and environmental crisis in the Niger Delta. However, by developing and highlighting conditions of interaction and interdependence between social and ecological systems, a landscape of destruction can be overcome and the effects of rising tides associated with climate change mitigated.}

<sub>Almost every year for long periods of time, Dhaka city in Bangladesh suffers from flooding. Dhaka is yet known for its poor drainage, but due to climate change it will become even more susceptible to extreme rainfall. Taking into consideration that Bangladesh is one of the most densely-populated, poorest, and severely corrupted nations, its capital city asks, more than any other delta city in the world, for a sustainable, pro-poor solution to flooding.
Mere technical approaches towards Dhaka’s problems, such as the construction of dykes or drains, will not suffice. Past experiences of proposed technical solutions in (the western side of) the city failed as no attention was paid to the existing logistic and housing challenges of the city, dwellers’ perception of flood risk, and their tradeoffs between losses and benefits of flood protection measures.
A new perspective on urban planning for Dhaka is presented: a participatory process to tackle flood management. We propose creating multi-use spaces within the city’s flood prone areas. Instead of being used for housing or permanent economic activities, regardless different levels of flood risk, sites mostly prone to flooding are to be reinterpreted for flexible and temporary uses, while reserving less flood prone to housing. These various uses are to be negotiated by the residents and landowners of these areas. We suggest combining temporary flood water storage and drainage facilities with diverse (seasonal) socio-economic beneficial uses and efficient housing. Being able to use and decide upon the use of these flood prone areas in dryer times provides an incentive for residents to participate in urban planning. On one hand, the focus is on training and awareness raising about flood management/adaptation measures, discussion forums for flood-related problems (water scarcity, water quality supply, drainage, livelihood provision, housing etc), and ensuring sustainable solutions and strategies are developed. On the other hand, the proposed participatory plan also promotes local income generation activities, such as banking, sale of products and possible small-scale gardening. Evacuation shelters with appropriate sanitation facilities are created for times of emergency times during periods of extreme flooding.

Sites will be selected to run pilot projects in high risk areas in (the eastern part of) Dhaka city. The selection will be based on technical information and on workshops in different resident communities. Once the pilot locations are identified, workshops will be run with community representatives on each site, to identify major problems related to floods. These identified problems form the basis to develop scenarios about the designation of these multi-use spaces, activities to mitigate flood effects, and incentives for operation and maintenance of the sites. During these workshops land rights, land lease, ownership of public spaces, concessions for use (e.g. prioritising access for use to displaced groups), possible relocation requirements, and maintenance of the space (e.g. if communities meet “good management” criteria, concessions can be prolonged; involvement of Municipality) should be revisited. In this process of site selection and developing scenarios for these sites, we envision an important role for students of the University of Dhaka. The selected scenarios will be a result of a contest among student teams of various backgrounds (social science, architecture and environmental science, etc).</sub>

_{To finance the multi-use spaces, we propose collaboration with the Grameen Bank (or similar bank) to do micro-mortgages. Micro-credit already proved to be successful in Bangladesh and investments by means of micro-credit are known to create a basis for ownership and long term sustainability in relation to maintenance. Micro-mortgages are based on a similar principle, however their advantage is that the multi-use space could be developed right away, while people can pay back the investment together step-by-step, for example at the start by contributing with local materials and non-skilled labour and later on by paying money they make out of socio-economic beneficial uses of the space. The local government or donors could accelerate the process by facilitating transport and constructing vehicles and take care of public infrastructure (water storage, drainage and emergency sanitation).
To conclude, we want to emphasize that negotiation processes amongst stakeholders within the city about the flood adaptation measures, reallocation and uses of the proposed multi-use spaces will require efforts and patience. For example, landowning elites will be only willing to collaborate when they will receive something in return, like for example the possibility to market products. As these negotiations are of high importance, we stress that adequate time and resources are to be allocated to the process of negotiation.
The described participatory process above is aimed at establishing efficient use and proper maintenance of the city through time and in turn, creates the basis for the project’s sustainability.}

_{The sea and the city: The Delta Wall is located on the North Sea shore, buffering the delta of the river Meuse. It functions as a chain of uniform multifunctional volumes that contains dams, sluices, dikes and locks. It is the project’s ambition to research whether the Maeslantkering can be reinstalled further up north, to shorten the Dutch coastline even more and to decrease the risks of flooding. The main goal of the Delta Wall is to keep the Rotterdam city centre free from climate threats instigated by the rising of the sea-level. In addition the Delta Wall offers space for water bound functions, alternative energy supply (windmills, hydropower stations, etc.) and city life program such as apartments, offices and public space. Thus, the Delta Wall guarantees not only safety for the existing city, it also provides a matrix for an entire new settlement that counters the ongoing expansion of the Dutch population.}

_{SEA BOUND PROGRAM: The Delta Wall consists of a chain of several similar U-shaped elements that can be positioned in two ways. Between each two elements of the Delta Wall a sea lock is installed to protect the other Delta Wall functions and the hinterland areas. The locks close whenever the sea reaches a critical level. The basement and courtyard of each element can be organized differently. If the high end of the U-shaped element is directed to the sea it can be used as a transfer zone for large cargo ships. The elements provide enough storage room for containers and also an immediate transit to barges and freight trains is possible. The goal is to reduce the traffic in the Rotterdam harbor and to accelerate the concept of Short Sea Shipping. Other sea bound functions are: a nursery for aquafarming, a pond for recreational purposes,inner canals for local and public transport and a marina for residents’ boats or for water-taxis.}

_{CITY LIFE PROGRAM: Parts of the Delta Wall chain can be doubled by stacking two rotated elements. In this manner the upper volume can contain additional program: apartments with an exceptional seaside view or open-floor offices adjacent to the courtyard. The upper volume consists of a collection of standard units that have a maximal flexibility: small studios, lofty apartments or large office spaces can be organized within this single building. Between the two stacked elements public spaces emerge. Spatially defined by large trusses these collective zones are connected continuously by bridges between the several elements. Together with fountain squares on the basements and panorama decks on the rooftops they form an omnipresent, transparent and sustainable platform for new city life in the Delta Wall.}

_{Bangladesh is almost entirely lying on the Gangetic Deltaic plain, and Dhaka, its capital city, one of the fastest growing urban centres in the world, is a highly flood prone region . The Region of Keranigunj, which lies on the urban fringe of Dhaka, is a frequent victim of seasonal flooding. Houses, lives and livelihoods are majorly affected in this region. The government funded Jilmil housing project in Keranigunj, aimed at providing shelter to the lower income groups who are the worst affected by flooding, is proposed to come up on a highly flood prone site, close to the Buriganga river.}

_{ISSUE: Floods severely affect structures, especially the lower income group shelters closer to the rivers. This group of people depend on the river and surroundings for their livelihood. The livelihood of lower income groups is highly dependant on the little open space that they can access close to their shelter. Lives and livelihoods are lost due to floods, mainly owing to the fact that there are no immediately accessible higher terrain regions available in deltaic plains. Income generating opportunities closer to the shelter, ensure the prevention of migration, which eventually result in slums and squatter settlements. Traditional living patterns in Bangladesh are characterized by communal interactions and activities. It is this sense of community along with livelihood opportunities that lend a to the sense of association to a place. The design intends to offer a possible solution of flood resistant community housing to the Jilmil Housing proposal. The proposed solution is a holistic one, which aims to create a community that retains the traditional social character of the region, and in times of floods, the design allows the community to help itself out to sustain and survive.}

_{SOLUTION: Borrowing from the age old tradition of constructing the shelter on stilts. Strategic stagger of units, each around 25 Sqmt, to yield terraces, some shared, some private. Terraces, a consequence of the design strategy, double up as flood or cyclone relief points. The free ground space, a consequence of the design strategy, can double up as an informal market, or can absorb other income generating functions. Strategic allignment of the modules to arrive at spaces of varying scales, that would respond to interactions of varying degrees, thus enhancing the communal integrity of the inhabitants. The design intends to offer a possible solution of flood resistant community housing to the Jilmil Housing proposal. The proposed solution is a wholistic one, which aims to create a community that retains the traditional social character of the region, and in times of floods, the design allows the community to help itself out to sustain and survive.}