DESIGN AGENDA FOR WESTERGASFABRIEK

In 1997 landscape architect Kathryn Gustafson together with Francine Houben of Mecanoo Architects, won the competition to design the masterplan for Westergasfabriek.

Gustafson Porter + Bowman’s design, ““Changement,” demonstrates a delicate balance between contamination and accessibility, invention and interpretation, restoration (of contaminated land) and revelation (of the potential of a post-productive site),” (Gustafson Porter + Bowman, 2006). 

Central to the design approach was the necessity to treat the contaminated soil onsite instead of transporting it offsite where it could create problems elsewhere. A cut-and-fill balance was calculated, bringing in new soil to displace polluted soil, retaining existing ground levels around the buildings and creating a new undulating terrain that was the consequence of surplus soil (Gustafson Porter + Bowman, 2006) (Landzine, 2015).

monitoring, maintenance & effectiveness

The success of the project can be attributed to an effective design process which incorporated public input and site-specificity from its inception. The use of the park is varied and intensive. Information markets and neighbourhood parties are held frequently on the Market Square which enable the constant involvement by locals. Westergasfabriek has transformed into one of Amsterdams main cultural venues. This is largely due to its availability for temporary cultural uses following the closure of the gas works. Today the combination of permanent tenants in the form of cultural enterprises, temporary rentals for festivals and events, and commercial and cultural letting provides a good basis for successful operation of enterprise within the park. (Project Westergasfabriek, 2008).

CONTEXT OF WESTERGASFABRIEK

Westergasfabriek was formerly one of Amsterdams two coal gas factory complexes and was completed in 1885 by the Imperial Continental Gas Association (ICGA). It was strategically located near waterways, the rail network and access roads. The buildings were designed in Dutch Renaissance style.

The gas produced at the plant was originally utilised for the city’s street lighting. In 1898 ICGA’s concession was withdrawn and the city council took over running the factory, expanding the site as production increased. 

The site was left heavily polluted, particularly with heavy metals, tar, cyanide and asbestos (Land8, 2015), making it difficult to repurpose the site. The the Municipal Energy Company (GEB), continued to use the site for storage and a repair workshop until the early 1990’s.

CONTAMINATION AND REMEDIATION

Westergasfabriek required separate contamination management plans for the buildings and the external environment and was designed by Arup Engineers (Land8, 2015). 

The remediation plan that was ultimately employed  was the ‘isolation-plus variant,’ approach designed by Arup. The polluted ground would be isolated beneath a layer of cloth with a ‘living layer’ of 1m deep, clean soil above. In total 35,000m³ of clean soil was brought into the site and 65,000m² of geotextile was used to cover approximately 51,000 m³ of polluted, redistrubutd soil. Where there was no planting, the ground was paved (Project Westergasfabriek, 2008). 

Willows and water loving plants including reeds are used in phytoremediation installations around and in water bodies and in plantings throughout the park to act as a vegetation cap, restricting the flow of groundwater (Land8, 2015).