IJburg is an urban development district in the eastern part of Amsterdam. Once the project is complete, it will comprise around 18,000 homes. IJburg is located and is being built in the IJsselmeer. This means that the existing natural functions and requirements of the water system needed to be taken into consideration in the realisation of the district. Both the first phase of IJburg and the second phase, in enhanced form, seek to realise natural values, an extraordinarily high density of 71 homes per hectare on average (in the second phase this number rises to 90 homes per hectare), preservation of the quality of the water in the IJsselmeer, as well high aesthetic appeal.
Water can be experienced almost everywhere on the islands: along the edges of the islands of course, but also near almost every single home at the middle of the islands, because of the waterways. One of the islands, Haveneiland, has a more stony and urban character and the largest proportion of multi-level construction. On Steigereiland the focus is on living on and around the water: experiments with architecture and private projects are also permitted. The reed islands hold primarily ground-level homes.
Pursuant to the introduction of stricter national and European laws, improvement of the natural values in the immediate vicinity of the new islands will require attention in the second phase.
The IJsselmeer is a Natura 2000 area. Its shallow, sheltered, nutrient-rich character and the abundance of crustaceans and water plants make the area attractive for waterfowl. Around 100 species of birds are found in the IJsselmeer, a number of which are protected. Although IJburg itself is situated just outside the protected zone, the construction of the new islands must be conducted in such a manner that they do not have any significant impact on the protected area. Moreover, IJburg is situated in the main ecological structure between the Vecht River region and Waterland areas. Creating islands proved to be a better solution than draining land, both for environmental reasons and in terms of the quality of life. The plans devote a great deal of attention to natural shores and proper water flow. The realisation of IJburg does not necessarily mean that the natural values will be diminished: the new district will offer more shores and shelter, and the water will become clearer because the sludge will settle. However, the construction of the new islands will cover mussel beds, and so the source of food for many types of waterfowl; this will be compensated by creating new mussel beds.
To compensate the construction of IJburg, Amsterdam is working together with a large number of other parties to create three new nature areas: Hoekelingsdam, Diemer Vijfhoek and Zuidelijke IJmeerkust.
Water system
The water system for the first phase of IJburg is unlike the water systems in other land reclamation projects in the IJsselmeer: it was decided that IJburg would be raised rather than drained. This extraordinary approach to land reclamation was chosen because of, among other reasons, the standstill principle, which states that the creation of new land areas may not impact the quality of the surrounding water. As such, precipitation on the IJburg islands is retained for as long as possible and treated. Most of the impervious surfaces are not connected to surface water. The runoff is allowed to infiltrate into the ground via special drains. Once it has infiltrated, the water passes through reed banks that further purify the water and into the island’s surface water. The clean water can then be discharged into the surface water of the IJsselmeer.
Traditional polders require continual close monitoring of the pumping of water from the drained area. The quality of the water that is discharged cannot be controlled, or only to a limited extent, particularly during peak drainage periods. Conversely, the system used for IJburg offers the possibility of treating the water before it is discharged. Projectbureau IJburg, 2007 Lang, 2009
Steigereiland in IJburg, Amsterdam
On one of the IJburg islands, Steigereiland, all utilities (gas, electricity, drinking water, sewers, telephone, cable) are supplied on the central platform designed specially for that purpose.
To ensure that the utility connections also function without difficulty in winter, pipelines heat the zone in winter to prevent the drinking water pipes from freezing. In the summer, they are cooled to prevent Legionnaires’ disease in the drinking water. Although a lock prevents the water from entering the IJsselmeer, the water level fluctuates by up to 60 cm. The platform has piles as its foundation, giving it a fixed level. The floating homes move up and down according to the level of the water; the connections between the platform and the homes are flexible. Meter cupboards are situated on the platform rather than in the homes. The homeowners are responsible for the flexible connections between their meter cupboards and their homes; the responsibility of the utility companies ends at the meter cupboard.
Since planning utility connections for floating or amphibious homes requires additional consultation and coordination with the various utility companies, more time will be needed in the planning phase of such projects. Projectbureau IJburg, 2003 Pötz et al., 2009
Literature
- Lang L. de & Milanovic M.; De afronding van Amsterdam (in PlanAmsterdam nr.2); DRO, Amsterdam, 2009
- Projectbureau IJburg; Waterbuurt West Steigereland - Stedenbouwkundig deelplan; Amsterdam, 2003
- Projectbureau IJburg; IJburg - De kracht van water; Amsterdam, 2007
- Pötz H. & Bleuzé P.; Vorm geven aan stedelijk water, SUN architecture, Amsterdam, 2009