In the Houtrak polder in the municipality of Haarlemmerliede and Spaarnwoude, Afvalzorg has constructed a large recreational area.

The area forms a natural border between the busy adjoining the Amsterdam western port area (Westelijk Havengebied) and the green buffer zone of Spaarnwoude.

The mounds of this work of art along the North Sea Canal attract recreational tourists. This project has been worked on since 2012, and a total of approximately 3 million m³ of secondary building material has been used. When het Groene Schip is completed, it will consist of 3 parts: a north, middle and south part. The north part of Het Groene Schip is now finished. It was largely constructed using Incinerator Bottom Ash produced by waste-to-energy plants.

According to the purpose of the buffer zone, the Houtrak polder will be reserved for extensive recreation. This involves a lot of nature, cycling tracks and pedestrian lanes (footpaths). Het Groene Schip will be delivered by Afvalzorg to Staatsbosbeheer, the Dutch forest management agency, with both a recreational design and a road to the top.

  • Period: 2013-2017
  • Tons supplied: 650.000
  • Material: AEC-bodemas
  • In cooperation with: Afvalzorg en Markus BV, Staatsbosbeheer en de gemeente Haarlemmerliede Spaarnwoude

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We are Rock Solid

From domestic waste to new raw materials


Since its establishment in 2006, Rock Solid has been a key player the Incinerator Bottom Ash (IBA) market. Applying bottom ash as a building material in groundwork and civic engineering projects results both in a reduction of the use of natural raw materials and in a cost reduction for contractors and waste-to-energy plants.

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