Even after an investment exceeding €800 million in new interchanges and extra traffic lanes, Dublin's M50 motorway will remain congested, an environmental impact statement (EIS) on the "upgrade" concedes. Frank McDonald, Environment Editor, reports.
"It is accepted that to protect the benefits of the scheme, it will be necessary in the future to implement specific demand management measures to control the level of traffic growth on the motorway", according to the EIS, prepared for the National Roads Authority.
In an oblique reference to congestion charging, it says "the need for, and the precise nature of, these measures will be considered following the opening of the scheme" in 2008 - assuming it is approved by An Bord Pleanála after an oral hearing due to open on December 14th.
The EIS predicts that traffic levels on the M50 will soar following its upgrade from around 80,000 vehicles a day at present to between 194,100 and 203,700 a day on different sections of the route - in both cases above the congestion threshold.
These levels do not take account of any increased demand arising from new motorways, such as the M3, feeding into the M50. Long-term forecasts to 2023 also assume that major public transport projects, such as the metro, will help to relieve it.
By then, according to charts in the EIS, there would be a huge reduction in average speeds on roads approaching the M50.
On the N3, speeds would drop from 45 k.p.h. in 2008 to some 25 k.p.h. in 2023, while on the N4 they would drop from 60 k.p.h. to just 10 k.p.h.
On most of the inbound roads into the city from the M50, the prognosis is even worse. By 2023, most cyclists would be overtaking cars stuck in "crawling gridlocked traffic despite all the new lanes and flyovers", according to Mr Eamon Ryan TD, of the Green Party.
Mr Ryan also queried how the cost of the M50 upgrade had risen from €316 million when mooted by the NRA in October 2003 to €580 million, after the inclusion of upgrades to the N2 and N3 interchanges, to €807 million, the figure given in the EIS.
Mr Michael Egan, the NRA's head of corporate affairs, said the main reason N2 and N3 interchange upgrades had not been included in the original package was that the NRA "didn't have the money". Since then, the "more elaborate plan" now being pursued had become feasible "on the back of West Link tolls".