Significant design changes have been made to the controversial plan to create a cluster of high-rise buildings behind George's Quay, in Dublin, including a further reduction in the height of its tallest tower, in a final bid to secure planning permission.
As envisaged originally by the Cosgrave Property Group, this curving glass tower was to be 102.3 m high. But Dublin Corporation, in its decision to approve the scheme last September, reduced the height to 80 m. Now, it is down to 73.7 m - some 15 m higher than Liberty Hall.
International architects Skidmore Owings and Merrill (SOM), who are acting for Cosgraves, frankly admit that scaling down the tallest tower - with a corresponding reduction in the other building heights, as required - represents a "vast improvement" on the scheme they submitted in May, 1998.
The architects had an opportunity to return to the drawing boards and redesign the £180 million project after An Bord Pleanala exercised its discretionary power to request an environmental impact statement from the developers. The board is dealing with a record 12 appeals against the corporation's decision.
An EIS had been sought by Lancefort Ltd, the company set up by conservationists to fight high-profile planning cases through the courts, if necessary. It argued that the scheme would have such a significant impact that an EIS was warranted.
The developers were obviously keen to retain approximately the same amount of floor space, so the revised scheme involves an increase in the footprint of the development to compensate for the reductions in height. It would provide 27,942 sq m (over 300,000 sq ft) of offices and 166 apartments. The scheme also includes a large atrium of more than 1,000 sq m, two pedestrian piazzas, a "dynamic pedestrian street" flanked by retail uses and a three-storey fitness centre, as well as a new entrance to Tara Street station, which directly adjoins the site, and the restoration of its railway viaduct.
According to the EIS, which was prepared by McHugh Consultants, the overall objective is to create "a vibrant downtown infill project" that would "provide a landmark for Dublin on the basis of its quality and its sculptural forms rather than on the basis of height" - an interesting way to phrase a climbdown. While the earlier scheme would have read as a tower flanked by somewhat lower buildings, the latest version is extolled by the architects as "a cluster of building forms that create a sculptural massing" because of their shapes, with clear glass giving them "a unique crystalline character". As redesigned, the George's Quay scheme consists of a grouping of glass towers with curving floor-plates and rooflines that are said to relate to significant landmarks in Dublin. Each of the curvilinear towers would rise from a heavy granite base similar in expression to the railway arches on the site.
They are also more sharply defined, seeming to swirl to a series of points. These harder edges are emphasised by the positioning of the penthouse levels, with the result that the roof plan resembles a scattering of petals. Another change introduces a slight outward splay in the top storey of each tower.
It is proposed that the two air-conditioned office buildings would be faced entirely in frameless clear glass with a low reflectivity to minimise glare. The interlinked apartment blocks would also be clad in glass, although as residents would be able to open the windows, these would hardly appear so crystalline.
According to SOM, the "sculptural quality" of the buildings would be re-inforced by defining the edges with a ceramic "frit-dot" screen to create a "gauzy effect". Sloping roofs in pre-finished metal would enclose all plant areas, leaving nothing protruding, to emphasise the scheme's "dynamic surfaces".
The overall effect, the EIS maintains, would be to "highlight the historic setting of the Custom House by providing a dramatic contemporary foil to it in the form of five glass sculptural towers" on a key site which could be seen as "a gateway location between the city centre and Docklands".
It suggests that the revised version, with the tallest tower reduced by a quarter of its original height, has "significantly less impact on the quality of the existing streetscape" than the earlier scheme and says it has been designed to minimise the impact on prominent historic buildings, such as the Custom House.
Building heights have been "dramatically reduced" so that the principal tower is now just eight m higher than a scheme by architects Keane Murphy Duff for Irish Life, sanctioned by An Bord Pleanala in 1991. But the EIS warns that, since the 1991 permission remains "live" until 2001, it "may still be implemented in full".
This is the Cosgrave Property Group's fall-back position if the appeals board rules against the current scheme. The alternative would provide 66,000 sq m of offices in seven interlinked blocks, the tallest of them some seven m higher than Liberty Hall, with almost no residential content and few public spaces.
The latest scheme, in the seductive language of the EIS, "treats the buildings as sculptural objects with commanding city views and spaces of light between them, not as a wall of bulky reflective building forms massed together. It creates a true landmark development rather than an expedient one".
In height terms alone, the impact of the revised proposal on the skyline, roofscapes, landmarks and city views is much reduced, according to the EIS. However, the authors concede that shadows would still be cast on the Custom House for up to an hour a day in mid-winter, though not at other times of the year. There would also be "shadow effects" on two existing office blocks on the George's Quay frontage of the site, occupied by Ulster Bank and Coopers and Lybrand - the only elements of the 1991 scheme to be completed. The predominantly residential area to the east would also experience some overshadowing.
As well as sun path diagrams, to indicate the scheme's shadowing potential, the EIS includes a visibility study from 31 locations which shows a "significant" impact on three of them - the Custom House, Lower Gardiner Street and TCD's College Park - and a "moderate" impact on O'Connell Bridge.
The final design was also subjected to a wind tunnel investigation by the Department of Aerospace Engineering at Bristol University. The calculations in its 44-page report suggested that the platforms and entrance to Tara Street DART station would have to be enclosed to eliminate "unacceptable" wind conditions.
Ultimately, whether any new building is regarded as appropriate in its setting is bound up with cultural values.
AS the EIS says: "For the whole of the 20th century, the making of tall buildings has been an important part of architectural endeavour. They have often been adopted as symbols of civic pride. In the 1960s, Cork and Dublin competed for the tallest building in Ireland, with Liberty Hall losing out by a few feet to Cork County Hall," as the EIS says. "It would not be surprising if tall buildings were again seen as symbols of progress and of the nation's success," according to the EIS.
However, it concedes this is "unlikely to be a universally accepted view . . . as current debate would indicate". And what the debate revolves around in George's Quay is not so much the architectural quality of the scheme, which is unquestionably of a high standard, but whether this is the right site for it.
Michael Smith, of An Taisce and Lancefort, believes the project is premature. "We shouldn't be thinking about granting permission for any skyscrapers until the Corporation does a scientific planning study to ascertain which parts of the city can take them."
In the meantime, An Bord Pleanala has a decision to make . . .