developments sea level rise
land subsidence
increase water supply
urban developments
consequences
water & dredge
risk of flooding, increased difference between land and sea level urban and agricultural areas prolapse and become saline
dredge soil types
waterlogged areas, risk of flooding limited water drainage and water storage
Figure 9 The dredge problem is related to global and national challenges such as handling sea level rise and land subsidence (causing saline seepage), increasing water discharge peaks (due to a more extreme climate), and spreading urbanization.
dredge pollution types
Figure 10 Location selection is based on overlay of soil types, pollution sources, saline seepage, transport infrastructure and spatial restrictions. The waste treatment site can be seen as part of large-scale landscape infrastructure providing green functions in the increasingly urbanizing Dutch Delta metropolis.
Figure 11 Deconstruction of the problem: Dredge can be separated into water and soil, wich is subsequently divided into sand, clay and peat. Different soil types contain different forms of contamination and require different cleaning processes, process times and process scale.
Figure 12 Thorough and detailed investigation of dredge problem’s diversity and quantification into exact numbers. pollution sources
amounts of dredge per dredge type in the Rijnland area
soil vs. dredge pollution type relation
cleaning method per dredge type
total amounts per dredge type
wherein natural and cultural forces and processes and time have a free hand to clean the soils and evolve the site into a park. The existing polder grid structure of fields surrounded by ditches is transformed into a new water system composed of ditches and separating dikes. The dikes devide the site into different contamination regimes, hereby creating a hierarchy in pollution with slightly polluted soils at the site’s borders and the most highly contaminated soils in the core of the site. Existing transport infrastructure is improved for importing dredge material by boat and truck. Within the outer ‘voids’ of the framework, dredge polluted by organic material is injected by sand-spraying the dredge onto the site. It separates heavy soils (sand) from lighter (clay and finally
peat) by a cleaning method called sand separation. A new and varied morphology automatically arises by differences in material gravity, subsidence and soil types, resulting in height and soil differences. Contamination is cleaned by oxygenation and landfarming: the cleaning of dredge specimen by biological breakdown of organic pollution. The core of the park is planned between the area where saline seepage exfiltrates and the supply channel. This second regime is separated from the outer area by a ring dike and ditch that hydrologically separate the two regimes. Here the more contaminated soils are cleaned. A mosaic is created by fields of different soil types. Combined with a variety of contamination, a multitude of milieus arise,
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