Wrapping the machine.

The product of progress has turned out to be overwhelming waste. Vast public incinerators on the urban perimeter were thought to solve the problem but only transferred pollution into the stratosphere. There is also the visual impact of a structure, as big as a power station, which casts a shadow over a whole district.

In 1912 Rotterdam chose the site on the south bank of the Maas for their public incinerator because of the ease of rubbish delivery by water. Over time housing gradually encircled the site so that in 1989 a law had to be passed setting standards to reduce and control harmful emissions from the incinerator chimney. This required an additional building, a `smoke cleaning machine', almost as big as the original incinerator plant. It filters out heavy metal, ash, acids and organic carbon hydrates and processes them using river water which is later purified and returned to the Maas. The remaining toxic material is then rendered harmless by chemical processing. This machine, rising through 10 levels of working platforms, like a living body, needs a skin for weather protection and sound insulation to protect the neighbourhood.

The idea of wrapping the machine was politically sensitive and much criticised, an alternative suggestion had been to relocate the incinerator. At the same time there was controversy over Rotterdam's new city bridge. For these reasons very little design time was available. Inception to completion took only three years. Unlike designing a building of volumes, from the inside out, the architect was presented with a fixed mass for which he had to design an elegant facade. Location was also influential. Residents nearby would be confronted by the structure daily and not only its size makes the machine prominent but its landmark position at the entrance to the Maas Tunnel.

In search of an image the architect took inspiration from a book, The Discovery of the Sky by one of the Netherlands' most famous authors, Harry Mulisch: `... the building stood like a clock--a sun dial, which showed the time not by shadow but with the help of light itself'. The changing play of sunlight on the building and the light reflected from the sky and water, depending on weather, season and time of day, led to the choice of Hoesch Isowand standard steel panels, which would be most reflective, maintain their appearance over many years, and accommodate windows and barred openings within their steel support frame. Uncoated metal also reflects more neutrally the changing whites, greys and blues of sky and water. At night the substance of the building dematerialises but the illuminated openings give motorists flashing past on the tunnel road glimpses into the machinery behind the screen.

The facades stand away from the edges of the floor plates so that escape stairs, all edge service ducts and sound insulation can be enveloped behind what, from the outside, appears to be a continuous curving wall. The east facade is a flat backdrop to the silhouette of the incinerator next door, with its large scale pipes and services exposed. Every other facade has an 80 m bow in plan and all corners have 4 m radii.

In Maythe Dutch artist Lydia Schouten, commissioned to design the site boundaries, constructed a three metres high Art Fence of red roses in front of the `Smoke Cleaner'. A comment, perhaps, on our propensity to simultaneously destroy nature's balance and make amends.