Speeding motorists using Dublin’s Port Tunnel will be caught using a new safety system which tracks their average speed through the urban motorway.

Automatic fines of €80 plus three penalty points will be applied if motorists are found to be taking less than 3.30 minutes to travel through the 4.5km tunnel.

The distance is calculated from the position of both cameras at the mouth of the tunnel, and the new system will go live from the autumn.

The move was announced by Transport Infrastructure Ireland (TII) and An Garda Síochána which said it would be the first average speed camera enforcement system in Ireland.

“We welcome this enhancement to the operations of the Dublin Port Tunnel,” Chief Superintendent Aidan Reid from the Garda National Traffic Bureau said.

“Due to an increase in traffic travelling through Dublin Port Tunnel this new enforcement system provides additional support toward maintaining a safe travel experience for all users.”

Traffic levels through the tunnel have increased by 40pc over the last five years which means that statistically, there is a greater chance of collisions and accidents.

Around 24,000 vehicles use the tunnel every day, and research suggests that use of the average speed detection system can reduce collision rates by as much as 50pc.

The average speed camera enforcement system monitors a driver’s average speed and if a driver is above the 80kmh speed limit, they will be hit with a fine and penalty points.

Once the system determines that a vehicle has exceeded the speed limit, it will automatically create a record of the violation which will then be transmitted to Gardai.

Drivers will notice large yellow poles with cameras being installed from tomorrow. These poles will support the average speed camera enforcement system. Once the cameras are mounted testing will commence. Upon completion of system testing it is anticipated that the system will go live later this year.

Average speed is recorded between two camera positions covering all lanes therefore switching lanes will have no effect on average speed monitoring.

The system will not have flashing lights or other operational indications, but it will be monitoring at all times.

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