Motorists commuting into Dublin city this morning are advised to avoid the quays because of new bus priority measures.
Sections of the north and south quays have been reduced to one lane for private cars which are also prohibited from turning right from Bachelor's Walk onto O'Connell Bridge - informed rte.ie.
The city council said it wanted to introduce the permanent changes now so that they are in place for the introduction of the Luas Cross City in December.
Testing and driver training are also due to start next month.
They are also designed to ease delays for buses on Bachelor's Walk which has been the worst bottleneck in the city for public transport.
Motorists travelling along the north quays from the west and north of the city will be the most affected this morning in what is the first real test of the changes.
Two lanes of traffic will be mostly reduced to one for cars from near the Four Courts.
There will also be a traffic light 100 metres from O'Connell Bridge giving priority to buses.
Cars will then only be allowed to travel straight ahead to Eden Quay or to turn left onto O'Connell Street.
The city council had previously warned that there is likely to be congestion if the same number of motorists use the quays rather than taking orbital routes or switching to public transport.
The changes have been condemned by the Irish Parking Association while Dublin Chamber has urged the city council to be prepared to alter the plan if problems develop.
However, the measures have been welcomed by Dublin Bus which said they highlight the importance of buses in tackling congestion in the city.
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