Drivers in Dublin, already being encouraged to leave their cars at home by the prospect of more quality bus corridors, now face being "actively diverted" from travelling through the city centre.
Under Dublin Corporation's new "traffic cell" plan, it is proposed to change the radial pattern of traffic movement in the capital to an orbital one. This involves closing off many of the through routes across the city centre, while still allowing access to a number of "cells" to facilitate shopping and residential needs.
The corporation is working on the introduction of the Clarendon Street cell, a move which would see the banning of left-hand turns at the bottom of Dawson Street in conjunction with the banning of right-hand turns at the bottom of South Great George's Street.
A large volume of traffic coming from St Stephen's Green would thus find it difficult, if not impossible, to take a straight route through the city centre and would be forced to divert along Cuffe Street and Kevin Street. Buses and taxis would be exempted.
In addition the corporation is examining the traffic which comes down Dame Street to the city centre and turns right at Trinity Street, moving through South William and Clarendon Streets. Banning the right turn at Trinity Street would remove this traffic, the corporation considers.
In the north of the city a small cell is already operational, bounded by Mountjoy Jail, Dorset Street, the canal and the North Circular Road, said Mr Eoin Madden, of the corporation's environmental traffic planning division. The Clarendon Street cell is waiting on the construction of a new link road between Mercer Street and Longford Street, which is to be ready by February.
A "city ring" is being developed which would see traffic circling the inner city rather than passing through it, Mr Madden said.
It will include Parnell Street, North King Street and Church Street.
"Traffic would be able to get into Dublin and into each of these cells, but would not be able to cross from cell to cell without first going back to the ring route."
An outer ring based on the "ferry routes" would see southbound traffic approaching the city from the west diverted along the traditional ferry routes to Dun Laoghaire. Northbound traffic would be encouraged to move similarly and not head for the city centre before turning north, as happens at present.