Poolbeg chimneys may have to be encased in fibreglass, says council

Medium-term maintenance programme for structures to cost several million euro

Dublin’s Poolbeg chimney stacks may have to be encased in fibreglass or concrete to ensure their long-term survival, according to Dublin City Council.

A maintenance programme to ensure the chimneys’ medium-term stability, which included placing steel caps on top of the structures in 2015, is expected to cost several million euro.

The twin chimneys, with their distinctive red and white paintwork, were built in the 1970s with a planned operational lifetime of 30-40 years. The associated power plants ceased production about 10 years ago and the chimneys were decommissioned in 2006 and 2010.

In 2017, ESB gave a written commitment to the chimneys’ ongoing maintenance for a period of 10 years. But measures to ensure the long-term survival of the 207m tall structures, such as encasing them in concrete or fibreglass, could change their appearance.

In response to a question from Green Party councillor Claire Byrne about the chimneys being placed on the Record of Protected Structures, Dublin City Council said the purpose of the maintenance programme was to stabilise the deterioration of the chimneys since they were decommissioned.

“The ESB state that in order to prevent further deterioration of the chimneys, steel caps were erected in 2015 and that the ongoing cost of the maintenance programme, which includes the removal of hazardous material and the decarbonising of the inner thermal lining, will run to several million euro, and that this will secure the chimneys in the medium term,” the council said.

Iconic feature

The council said the chimneys had now become an iconic feature in the Dublin skyline but their stability in the longer term “may give rise to the need for the structures to be encased in a new concrete or fibreglass casing”.

“These interventions are likely to alter the appearance and integrity of the structures as originally designed. ESB is concerned that adding the chimneys to the Record of Protected Structures will not provide any additional security to that provided under the maintenance programme, and may actively impede any ongoing structural interventions or necessary external cladding in the future.”

The ESB said it continued to work closely with the council on the future of the Poolbeg chimneys. A spokesman said if fibreglass were to be used to protect the chimneys, it would likely involve encasing sections of the chimneys in the material, rather than the entire structures.

“ESB also commissioned specialists to carry out a condition assessment of the chimneys. This included an assessment of the foundations of the chimneys. As the findings are still under consideration, we have deferred any further works until we have established with greater certainty how they will impact on the remaining lifetime of the chimneys,” the spokesman said.

ESB declined to give an exact figure for the cost of the medium-term maintenance programme beyond “several million euro”.

The site at Poolbeg continues to be an operational power station; though the power station does not use the chimneys for its 470MW gas turbine combined cycle plant which generates electricity for more than half a million homes in Dublin and beyond.