At its 32nd session (Quebec City, 2008), the World Heritage Committee urged the State Party to halt the construction of the 100m high building of the Vienna Central Train Station project, the height of which would protrude above the trees on one side of the Belvedere Palace Park, and further, to carry out, in collaboration with the World Heritage Centre and ICOMOS, a comprehensive visual impact assessment of the entire project, fully sensitive to impacts on the Outstanding Universal Value of the property.
The State Party provided a report on 26 January 2009 which addresses the concerns raised by the Committee. The report notes that the Austrian authorities have succeeded in reducing the height of the tower from 100m tower to 88m. The report notes that this will reduce the height of the building by more than the one or two storeys previously noted by the State Party as the height reduction necessary to ensure that the building will not be visible from the park of Belvedere Palace.
The State Party report also emphasizes that the height reductions and relocations of the high-rise buildings made in the course of refining the master plan for the Vienna Central Train Station project are such that none of the 11 buildings would be visible from the park of Belvedere Palace. Presumably due the height reduction noted, the State Party report does not make reference to the “comprehensive visual impact assessment of the entire project, fully sensitive to impacts on the Outstanding Universal Value of the property”.
However, the state of conservation report of 2008 demonstrated the necessity for such a visual impact assessment to be carried out utilising a transparent and objective methodology to permit assessment of visual impacts; which would:
- define all visual axes;
- define all view points from which visual assessments would be important, including the south front of the Upper Belvedere Palace, and the area of the park (part of the World Heritage property) immediately adjacent the Vienna Central Train Stationproject grounds;
- measure impacts during all seasons including both winter (when the loss of foliage will make high rise construction more visible), and evening (when illuminated towers may increase visibility).
The World Heritage Centre and ICOMOS consider that carrying out this assessment would serve several purposes, including:
- involvement of all parties to collaborate in developing an appropriate methodology to preserve the Outstanding Universal Value of the property;
- definition of permissible heights within a mutually agreed objective, and transparent process, on the basis of this agreed methodology;
- the opportunity given to the World Heritage Committee to review the methodology proposed and its results in this context;
- the opportunity to share methodological lessons learned with other World Heritage properties where similar visual impact issues are emerging.
While the World Heritage Centre and ICOMOS appreciate the voluntary reduction by the State Party of the controversial high-rise building from 100m to 88m, they reiterate their earlier contentions that a comprehensive visual impact assessment of the entire project as requested by the World Heritage Committee at its 32nd session, would be the best basis for establishing such height parameters.
The World Heritage Centre and ICOMOS further note that any visual impact assessment of this project has to assess these impacts along all view axes, important views and view points, and in all contexts (season, time of day) which could affect the Outstanding Universal Value of the property.