It sounds hardly credible but it's true - no fewer than 540 new bridges are to be built over the next five years as part of the £4.7 billion roads programme in the National Development Plan. And the National Roads Authority is under such political pressure to deliver on this programme that the issue of design quality is being sidelined.
With 630 kilometres of new road construction in the pipeline, there is an understandable impetus to get on with it - using public-private partnerships (PPPs) and design-and-build contracts to speed up the process.
And everybody involved knows deep-down that such forms of procurement tend to put design way down the list of priorities.
The NRA came under considerable pressure to face this issue at a day-long conference in Dublin recently, held in collaboration with the Arts Council. But its representatives stopped short of conceding that the speed and cost of constructing new motorways were impediments to making any commitment to place more emphasis on design quality.
Even though it's highly improbable that the NRA will complete every element of the National Development Plan's accelerated roads programme by 2006, we must take it that these roads - and the bridges that go with them - will be built at some stage.
The real issue, as always, is what legacy might be left for future generations.
Pat Maher, the NRA official in charge of bridges, put them in three categories. Apart from the basic "bread-and-butter" motorway overbridge (or underbridge), there will be new bridges for traffic and/or pedestrians in urban areas as well as major river and estuary crossings. And the design requirements differ in each case.
Obviously, in the latter two categories, siting and visibility would be more important, which is why Dublin Corporation commissioned Santiago Calatrava, the world's best-known bridge-builder, to design two new bridges for the Liffey - one in the Docklands area and the other further up-river at Blackhall Place, near Heuston Station.
But under a PPP arrangement, design quality ranks last on the list of priorities. The way the NRA sees it, the package deal on offer from private interests tendering for the various schemes must score highly on financing and delivery, long before a judgement is made on what any particular bridge might actually look like when it is constructed. Even before PPPs became ideologically de rigeur, the design of road bridges was a hit-and-miss affair. In most cases, county councils engaged several firms of consulting engineers to design bridges for the same road scheme. What this produced, arguably, was visual chaos - as seen, for example, on the N3 Blanchardstown bypass.
Where new roads or motorways are planned, the NRA should consider holding competitions to design a generic overbridge for each national route, adaptable to the local topography as required, instead of commissioning a plethora of consulting engineers to design multifarious bridges, often within sight of each other.
Some of the motorway overbridges built during the past decade or so are positively hideous. The worst pair, perhaps, span the N7 in the Curragh. Designed to provide horses being exercised with a traffic-free way to cross this busy dual carriageway, they are clad in pre-cast aggregate and constitute a visual horror for motorists with sensibilities. By contrast, one of the overbridges on the N11 at Killarney Road, near Bray, has been widely praised for its elegance.
Designed by consulting engineers Roughan O'Donovan in collaboration with Grafton Architects, it is a classic example of what can be achieved when these two professions break down the barriers between them.
According to Joe O'Donovan, one of the keys to success in such a collaboration is to forget about the issue of "ownership", in terms of architect versus engineer. His firm has certainly had no qualms about bringing architects on board for the design of bridges; unique among engineers in Ireland, it has been doing so for the past 15 years.
Internationally, it is much more common for architects to be involved in bridge design. One of Santiago Calatrava's great strengths is that he qualified as both an architect and engineer, so he is in a position to offer clients all-in-one advice - not just on design concepts for new bridges but also all the calculations required to ensure that they stand up.
But collaborations between architects and engineers on bridge design don't always work out. When London's Millennium Footbridge linking St Paul's Cathedral with the Tate Modern wobbled embarrassingly on opening day, the PR firm acting for its architect, Lord (Norman) Foster, referred all queries to the structural engineers, Ove Arup and Partners.
Dutch architect Ben van Berkel has collaborated with a team of professionals, ranging from engineers to graphic designers, to produce such spectacular works as the Erasmus bridge in Rotterdam. And the graphic designers are not brought in as an afterthought; they are part of the orchestra, involved from the outset of the design process.
One of van Berkel's major projects, the Propendorpse bridge in Utrecht, which is currently under construction, is the product of a design-and-build contract. What this shows, according to Antoinette O'Neill, architecture adviser at the Arts Council, is that PPPs can be quality-controlled where there is a real commitment to good design.
In Ireland, however, the danger inherent in our narrow interpretation of design-and-build PPPs is that they effectively "sign over" a bridge at tender stage. And because the PPP partner is in the driving seat, the bridge designer has no control over the quality of its construction, as Joe O'Donovan warned those attending last month's conference.
Shelley McNamara, of Grafton Architects, stressed that the goal all bridge designers should be striving for is beauty, which could only be achieved by treating design and structure as integral elements. That's how the masonry arch bridges of the 18th century were built, not to mention the great railway viaducts of the Victorian era.
Prof Seβn de Courcy (former professor of engineering at UCD), who knows more than most about the bridges of Ireland, suggested that their successors are likely to be constructed of prefabricated concrete units. But he is not alone in believing that the durability of concrete as a material can be complemented by good design to achieve a successful result in terms of visual expression.
Though the NRA seems unfamiliar with the concept, what's clearly needed is an "aesthetic review" of bridge designs - as proposed by Rachel MacRory, architecture adviser to the Department of Arts and Heritage. This would involve some form of external assessment along the lines adopted by Dublin Corporation for major projects in the city.
It is simply not enough that the NRA and the various local authorities should cover up for poor design with such figleaves as the "1 per cent for art" scheme. Though this has produced some fine pieces of work, notably Remco de Fouw's traffic-mad globe on the Naas bypass, it cannot be expected to compensate for poor infrastructural design.
Ironically, it is an award-winning Irish architect who has been making waves in integrating at least one motorway with its environment. Tom de Paor's work on the A13 in Dagenham, east of London, manipulates the road edge in a strategic way, with lighting and other effects, to create a cohesive and meaningful visual experience for its users.
If de Paor receives a similar commission at home, it will show that the relevant authorities - not least the NRA - have travelled some distance in terms of visual awareness. But unless immediate action is taken at the highest political level, there will be no control over the PPP process to ensure a minimum standard for the 540 bridges we now plan to build.