Severe restrictions for traffic going to and from Dublin Airport on the M1 are to begin tonight and continue for the next four weekends - the busiest time of year for passenger numbers through the airport.
The restrictions are due to essential work on the Dublin Port Tunnel and will involve closing a section of the N1/M1 motorway at Santry, with traffic diversions via Finglas and Malahide roads and the M50.
Aer Rianta which expects 1.6 million people - mostly holidaymakers from all parts of Ireland to use the airport this month - has expressed regret at the closure and advised motorists to allow extra time for their journeys, particularly those who are unfamiliar with the layout of surrounding roads.
The closure of the M1/N1 at Santry will begin at 10 p.m. to facilitate the building of the access portal for the Dublin Port Tunnel.
The Shantalla Bridge over the M1 at Santry will be demolished and replaced with a temporary structure just below the current bridge.
While building the portal will take nine to 12 months, Dublin City Council says replacing the bridge with the temporary structure will take four weekends at most, and maybe just three.
Work will be around the clock and the M1 will reopen to traffic each Monday morning at 6 a.m.
When the portal is completed, the Shantalla Bridge will be rebuilt.
Mr Tim Brick, an engineer with Dublin City Council, said he accepted that due to the airport traffic volumes did not fall on this road in August as they do in other areas.
But he said restrictions in place for a year at Whitehall had reduced the average annual daily traffic volume from 36,000 vehicles in September 1999 to about 26,000 now.
He also said it "would be unthinkable to do it at any other time of the year", particularly in wet weather with low hours of daylight, or during the Christmas rush.
Mr Brick said the closure was essential for building the tunnel access, which had a four year timetable that "fortunately" scheduled the bridge demolition in summer.
A temporary bridge will be built this weekend; links to the temporary bridge will open the following weekend; and the Shantalla Bridge will be knocked down on the third weekend.
The fourth weekend was described as "insurance in case things don't work out".
A spokeswoman for Aer Rianta said the company regretted the closures but could see Dublin City Council's difficulty.
The spokeswoman said Aer Rianta had been advised by the council of its intentions and while it did not suit the airport, she could see the difficulty in removing the bridge when the schools in the area are operational.
Aer Rianta expects up to 350 charter flights - most arriving at the weekends, to use Dublin Airport during the period of disruption.
Alternative routes are as follows: northbound motorists approaching Dublin from the south/west should use the M50.
Motorists travelling from the city should follow sign-posted routes and travel via Finglas Road to the M50 or via Griffith Avenue and Ballymun Road to the M50.
Motorists travelling to the south and west of Dublin should use the M50.
Motorists travelling to the city should use the sign-posted route via Malahide Road, Coolock and Fairview.
The southbound slip road from Shantalla Bridge onto the M1/N1 is a bus lane and will have restrictions.
To avoid unnecessary delays airport/city-bound traffic will be directed to use the sign-posted diversion routes.
Local access only will be maintained at all times.
Further information is available from the Dublin Port Tunnel Information Office at (01) 245-9999.
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