Raw sewage flowed into Cork reservoir source river for five months

Raw sewage was flushed for five months into a source river for one of Cork’s main reservoirs.

While Uisce Éireann insisted the reservoir's water quality was not affected, the utility only notified the Environmental Protection Agency (EPA) of the incident after being contacted by The Echo.

In March, a new 30-apartment development in Glanmire was connected to the storm drain on East Cliff Rd instead of to the adjacent sewage mains.

Sewage from the Ashbrook apartments was then flushed at intervals into the storm drain, flowing in turn into an overflow pipe on the Butlerstown bridge, and down to the water below.

The Butlerstown river feeds into the Glashaboy reservoir, which produces approximately 20m litres of water per day and serves Glanmire, Glounthane, Carrigtwohill, Little Island, and Cobh, an area with an estimated population of 40,000 people.

Normal water levels in the Butlerstown and Glashaboy rivers masked the sewage, but the recent hot weather caused levels to drop significantly. As a result, in the past month the water treatment plant was forced to cease operations three times due to dangerous levels of ammonia caused by sewage.

On August 13, members of the public walking on the new Glanmire greenway noticed the smell and saw clumps of toilet paper and human excrement falling into the river.

The Ashbrook sewage pipe was disconnected from the East Cliff Rd storm drain in the past fortnight, with the sewage being stored at the development’s holding tank, and removed periodically by private contractors.

Strong smell of sewage

There was a strong smell of sewage around the apartment development’s holding tank this week.

Uisce Éireann said drinking water supplied from the Glashaboy water treatment plant remained safe to drink.

“At no time was there any impact on the quality of drinking water supplied to customers or any risk to public health,” a spokesperson said.

They said water treatment plants are equipped with continuous monitoring and automated protection systems to safeguard drinking water quality.

“As designed, these systems temporarily suspend treatment operations when changes in raw water quality are detected, ensuring the continued protection of drinking water supplies.

“Upon becoming aware of an issue relating to a wastewater connection at a private development which resulted in wastewater entering a local watercourse, corrective works were undertaken and the matter has since been resolved,” they said.

Workers’ Party councillor Jerrica Struthers said successive governments had created a situation in which, rather than work directly for Uisce Éireann, public water workers were moving to other departments.

When you push out local council workers who know the area, you lose decades of expertise, meaning disasters like this become our daily reality.

A spokesperson for Inland Fisheries Ireland said it had not received reports regarding pollution of the Butlerstown river but would carry out an inspection.

The EPA said it was informed of the incident in Glanmire by Uisce Éireann last Tuesday afternoon — three hours after The Echo had asked for comment on the situation.