Massive gas pipeline to be laid under River Foyle

A massive gas pipeline will be laid under the River Foyle tomorrow in a £3.1m project which is the first of its kind ever undertaken in Ireland.

Firmus Energy is planning to lay the 660 metre pipeline in the early hours of tomorrow morning after years of planning and months of preparatory work.

Journalists and MLA's at the specialised drilling rig used in the construction of teh River Foyle Crossing which will see gas piped 30m underneath teh River from Strathfoyle to Thornhill. Picture Martin McKeown. Inpresspics.com. 03.10.18

Journalists and MLA's at the specialised drilling rig used in the construction of teh River Foyle Crossing which will see gas piped 30m underneath teh River from Strathfoyle to Thornhill. Picture Martin McKeown. Inpresspics.com. 03.10.18

This has included drilling a hole in the rockbed under the River Foyle from Culmore to Strathfoyle and beneath the Derry rail track, using a 50 tonnes drilling machine to accommodate the new gas line.

Those involved in the project have said that the new pipeline will ensure the growing number of homes and businesses across Derry City are supplied with gas for the next two decades.

At present the only pipline to serve the 10,541 households and local businesses which have already switched to gas is located on the Craigavon Bridge.

The new specially manufactured two-inch thick pipe, which is currently laid out from Pitchers’ Restaurant to Thornhill College, will be fed through the drilled hole from the old Thornhill College site to Strathfoyle once final checks are completed today.

At a special briefing and site visit attended by MLAs, business figures and local journalists on Wednesday, Firmus Director of Engineering, Eric Cosgrove, said the project was a massive undertaking.

“This weekend is the big push,” he said. “We will hopefully be pulling the big pipe in underneath the Foyle in one go over about 10 hours, starting at 3am on Saturday morning.

“Derry is our biggest city for connections. They are all supplied with one pipe at the moment. What we have to do now for future expansion of the city, for Skeoge, for new housing, is to keep the gas supply going, so we need another supply undernealth the Foyle.

“We have been talking to the Utility Regulator now for three to four years about this and the Utility Regulator gave us permission to do this work approximately seven or eight months ago.

Main contractor, Kier and a County Derry firm, McCormack and Sons, a specialist directional drilling sub-contractor from Maghera, have been chosen to carry out the works.

Explaining the preparations leading up to this week, Mr. Cosgrove said: “Essentially what we do is we dig a big pit on one side of the Foyle on the grass. We did another pit on the other side at the old Thornhill College site and we put 700 metres of steel rods underneath the river bed, approximately 25 metres underneath the sea bed. What we do then is join the pipe and those rods then get retracted out and that pulls the pipe out. So this pipe is one big length of polyethylene pipe welded together.”

At present, he said, there are roughly 200 kms of gas mains in Derry, installed over the last 10 to 12 years. The new pipeline will link into the existing network. Due to salmon arriving in the river by the end of October, the project must be completed before then and the gas supply will be ready by the end of the year.

Jonathan Strain, Construction Manager, said: “We would like to say a special thanks to the Derry Port Authority, Thornhill College, Strathfoyle residents and Diocese of Derry for their continued help and support throughout the project.”

WWII DEVICE

Mr. Cosgrove confirmed that a World War II explosive was found on the riverbed during preparatory radar exploration work for the gas line project, which is located close to the old World War II jetty on the Foyle. “By bad luck we were pulling in the sound monitor and we snagged an old World War II projectile that was in the river,” he said. “The workers were pulling out the sound monitor when the rope snapped and the device fell back into the river.”

Mr Cosgrove then phoned the coastguard and PSNI and specialist teams came and carried out a controlled explosion.