The Cork-Dublin Transmission Pipeline and Gas Distribution to Kilcullen

Gas distribution network in central Kilcullen from the Dial Before You Dig website. Image courtesy Gas Networks Ireland.

On 4th March last year, a press release was issued by Uisce Éireann to media and local public representatives to the effect that:

“Civil Engineers are carrying out pre-work activities on the 225mm pipeline, which involves a localised crossing over the High Transmisison (sic) Gas main under the supervision of Gas Networks.”

That line is the Cork-Dublin gas transmission pipeline, and the work was being carried out at Kennycourt, just after the right-hand turn for Kilgowan when heading towards Dunlavin. The 225 mm pipeline was a water main which was being installed for the Dunlavin Water Supply Rationalisation Project.

The gas transmission network in Ireland. Image courtesy Gas Networks Ireland.

The Kinsale Head Gas Field was discovered in 1971 by the US Company Marathon Oil Corporation. Gas well heads were installed in 1977 and production began in 1978. Construction of an 18-inch (450 mm) diameter pipeline to Dublin by Bórd Gáis Éireann began in 1981 and was completed in 1983. The pipeline runs cross-country through the Kennycourt, Mooretown, Carnalway, Harristown area on its way to Dublin. It passes under the river near Ardenode. It operates at 70 bar, or approximately 1015 psi (pounds per square inch). For comparison, your car tyres are pumped up to about 2.2 bar. 
Gas Networks Ireland doesn’t publish a fixed burial depth for transmission pipelines. High-pressure gas transmission pipelines in Europe are designed in accordance with standards such as EN 1594, which set out functional requirements for pipelines operating above 16 bar. EN 1594 sets out functional requirements for high-pressure gas pipelines above 16 bar, including protection from external interference. Burial depth is determined by design and risk assessment and varies depending on location, with greater cover typically used at road crossings, railways, and other high-load areas.
You’ve probably seen the white poles along roads with what look like cowls on top, marking the line. I erroneously thought these were some type of safety vent, but when I reported a damaged one near Coghlanstown, which had probably been cut by a tractor during autumn hedge cutting, I learned they’re simply markers, and what looks like a cowl is in fact a disk which helps aerial survey teams, including helicopter patrols, identify the pipeline route. A Prior Information Notice (PIN) for Gas Networks Ireland’s aerial surveillance services was published in June 2024 on the Irish Government’s eTenders portal which stated that:

“Gas Networks Ireland requires the provision of an aerial surveillance patrol service of their gas pipeline system in the Republic of Ireland and Northern Ireland to ensure there are no works or digging being carried out on or near the pipeline and no excessive vegetation growth on or near the pipeline.”

Kilcullen’s gas supply comes from a hub connection on the Cork-Dublin pipeline located north of Ballymore Eustace. You can register and view an interactive map of the transmission and distribution network, with detail down to street level, on the Dial Before You Dig website here.

Further Reading