Restoring blanket bogs could improve tap water

Glens of Antrim scheme to re-wet bog also expected to help wildlife and environment

Merlin: the area is home to threatened birds such the merlin, hen harrier, golden plover and red grouse and rare plants such as the marsh saxifrage and bog orchid. Photograph: iStock

Merlin: the area is home to threatened birds such the merlin, hen harrier, golden plover and red grouse and rare plants such as the marsh saxifrage and bog orchid. Photograph: iStock

 

A project in Co Antrim has established that restoring blanket bogs in Ireland could be an important factor in improving the quality of water flowing from household taps while also helping the environment and wildlife.

Environmentalists and water treatment experts are now examining the project which is being conducted on a 2,000 hectare (4,942 acres) blanket bog site in the Glens of Antrim owned by Northern Ireland Water.

The Northern Ireland Environment Agency and the Royal Society for the Protection of Birds are also involved in the scheme to re-wet the bog. As well as providing cleaner water, the project at Garron Plateau blanket bog should maintain and improve the flora and fauna in the area, according to Northern Ireland Water’s catchment manager Roy Taylor.

The area is home to threatened birds such as the hen harrier, merlin, golden plover and red grouse and rare plants such as the marsh saxifrage and bog orchid.

Irish Water is also keeping an eye on the project although it hasn’t made any comment about whether it could be applied in the South as it is at an “embryonic” stage. Nonetheless while this experiment is very much in its early days, Mr Taylor is confident that it will be successful and could have wider application across the island. He said that it has also been done successfully in some water companies in England. “I am confident that in the long term this will pay. Certainly other water companies have seen it pay,” he said.

Damaging drainage

He explained that previously excessive drainage going back a number of decades had damaged the blanket bog, with the result that dirty, discoloured, peaty water was flowing into NI Water’s Dungonnell Reservoir on the site. “The bog was drying out and beginning to erode. Then when you got heavy rain storms it washed the peat down into the reservoir, leaving it a lot more difficult, and expensive, to treat the water,” said Mr Taylor.

He said that the peaty water going through the treatment plant from the reservoir required the use of a considerable and expensive amount of chemicals to clean the water.

Restoring the bog however resulted in cleaner, clearer water entering the reservoir from the bog and less need for cleaning chemicals. Mr Taylor explained that the bog is being restored by building a series of small dams throughout the site resulting in the raising of the water table.

This led to the re-growth of sphagnum moss and heather and other vegetation which helped absorb and filter the water. Using an analogy of the sponge he said: “Imagine a cup of water and you pour it onto a piece of plastic. It flows straight off. But if you pour it onto a sponge it soaks it up and it does not spill everywhere. That is what we are doing.”

Reducing chemicals

Mr Taylor said that the bog also sequestered carbon which was an added environmental benefit. “Removing pollutants at water treatment works involves using costly chemicals and our aim is to help improve land management so that water quality and quantity is improved at source, long before it reaches our works,” he added.

“This blanket bog restoration is not only a win in terms of raw water quality which is so vital for NI Water, but it is also a win on carbon, the environment and wildlife conservation,” he said.

The project was discussed during a recent environmental conference in Dublin. The author and environmental campaigner Tony Juniper noted how “for a long time, nature was valued for its spiritual, aesthetic, moral and scientific value” but that now the “conservation agenda is beginning to embrace the monetary value of nature too”. And this was apparent in the experiment at Dungonnell.

“The blanket bog looked like a wasteland until it was discovered that its restoration would improve the quality of the water,” he told the Making Nature Count conference in Dublin.