Dublin will need improved land zoning and new infrastructure if it is to accommodate the continuing urban sprawl, according to a report by the European Environment Agency (EEA).
The study - entitled Urban Sprawl in Europe - The Ignored Challenge- predicts the Greater Dublin area will need to accommodate up to 480,000 additional residents by the year 2020.
It said high house prices in Dublin have driven the population towards the rural fringes of the city where it is cheaper to buy or build a house.
The EEA suggests that the small size of apartments in the city centre has forced families with children needing more space to move out of the city where prices are lower and housing is more affordable.
The report contends the urban sprawl has been facilitated by the planning regime, which it says imposes few constraints on the conversion of agricultural areas to low-density housing areas.
It said the observable preference was for single-family houses in open countryside with the benefits of the proximity to the capital or other urban areas.
The growth of residential areas around Dublin appears to follow the line of road and rail transport, suggesting a preference for rural living but with the benefits of proximity to urban areas including employment.
The agency said commuting times are long and the lack of orbital roads and rail networks means a journey through the centre is needed to get from one side of the city to the other.
By 2025, it predicts the outward expansion of residential areas in the Greater Dublin area to increase by 110 per cent.
The main development axis, it suggests, is to the north from the Greater Dublin area along the line of the Dublin-Belfast corridor.
It recommends that future development should encourage Dublin City to develop from a monocentric to polycentric relationship with the neighbouring cities of Dundalk, Newry and Drogheda.
The report pinpoints Dublin as a typical example of the problem of urban sprawl in Europe which it says is the most urbanised continent on the globe, with approximately 75 per cent of its population living in urban areas.
By 2020, approximately 80 per cent of Europeans will be living in urban areas and as a result, the demand for land in and around cities is becoming acute.
The report warns that sprawling cities demand more energy supply, require more transport infrastructure and consume larger amounts of land.
"This damages the natural environment and increases greenhouse gas emissions," it said. "Among the consequences are climate change, increased air and noise pollution. As a result, urban sprawl impacts directly on the quality of life of people living in and around cities."
