A Dublin metro will only work if the suburbs it serves are replaced by apartments, writes Frank McDonald, Environment Editor
Cabra, Dundrum, Finglas, Kimmage and even parts of Tallaght will inevitably end up on the chopping board if the next government proceeds with the plan for a metro in Dublin. This is because such a high-volume public transport system would only work in a high-density urban environment.
Low-density suburban housing with front and back gardens and, in most cases, an ageing population that is also falling steadily, could not provide the numbers to make a metro pay. So, for a kilometre on either side of the proposed lines, the housing will have to be replaced with clusters of apartments.
This is not something which the politicians who say they support a metro are crowing about (or have even considered). Far from it. That would raise too many hackles in the areas most directly affected. However, the demolition of suburbs along the route of the metro is a prerequisite for the project.
The metro would have a capacity of up to 50,000 passengers an hour, yet the highest level of travel demand on any corridor in the Dublin area is 15,000 an hour - by bus, train, bicycle, motorbike and car. In other words, the metro would be able to carry nearly four times as many, if they all travelled by public transport.
The outgoing Government is working on the assumption that the private sector would invest substantially in the €8 billion project, through a public-private partnership (PPP). If so, the only way it could be made to pay is by boosting demand - and, therefore, potential profits - along the entire length of the metro lines.
The Dublin Transportation Office, whose Platform for Change strategy forms the basis of the metro plan, has been reticent in highlighting its knock-on consequences in terms of urban density. However sources say it is inevitable as land values rise in areas served by the metro that developers would move in to capitalise on it.
"Look at what's happening already on Sandyford Industrial Estate," said one transport expert. "Just because Luas is coming, they are pulling down perfectly good buildings and developing the sites for six-storey office blocks. Why wouldn't the same sort of pattern be repeated in residential areas on the route of the metro?
"That band of low-density suburbs like Cabra, Crumlin and Kimmage with ageing, declining populations will have to be redeveloped. They're not attractive areas for younger people and they have no architectural value."
After the DART service began in 1984, property values rose all along the line from Howth to Bray and under-used sites were developed for apartments or offices. The difference now is that, under section 49 of the 2000 Planning Act, the public authorities would be able to recover a proportion of the increase in values.
The DTO is working with the Dublin local authorities on integrated framework plans for the metro. Digital aerial photographs of the city, with the metro lines superimposed on them, are being examined to identify under-used areas with the highest development potential - and these include low-density housing.
The inner city has been divided into 10 or 12 zones. The 90-acre Grangegorman site is a prime candidate for redevelopment as it is located right behind Broadstone, one of the key points on the proposed metro. So is the area around Heuston Station, including a large part of the 60-acre Guinness site.
A study by Iarnród Éireann and the DTO is examining alignments for the proposed tunnel between Heuston and Spencer Dock - not just the geological and engineering issues, but the potential along the line for higher-density development. "It's releasing potential we never knew existed," said John Henry, the DTO's director.
"What we're finding is that the overall transport network we have proposed in Platform for Change is bang on and in the right place," he declared.
"And that wouldn't have been the case if we had taken an incremental approach by merely putting in bus corridors, upgrading existing rail lines and adding to them here and there."
The DTO aims to create a dense public transport in the Dublin area - a "walk and ride system", as Mr Henry calls it - so that everyone would be within walking distance of the DART, Luas, a QBC (quality bus corridor) or a metro line.
But with a price-tag of €8 billion over 15 years, was the strategy not driven by a perceived availability of unlimited funds when it was drawn up in 2000? "We weren't restrained in our thinking because of the cost of it," he conceded. "What we wanted to find out was what was the right answer to Dublin's transport problems."
Asked whether the Department of Finance had bought into the metro plan, Mr Henry said its officials had raised issues about costings before it was adopted as Government policy in July, 2000. However, he cautioned that the Department was probably expecting more private-sector funding from a PPP than it would get.
Noting that there was now cross-party support for the metro, he said nobody has challenged the concept. "We're saying we can solve the problem of Dublin traffic if you do what we say should be done. If you don't do it, the problem will get worse and worse and then the economic life of Dublin would be at risk."