Fears that knotweed will delay flood works

Engineers have attempted to allay fears about major Japanese Knotweed infestation delaying a €8.1m flood prevention project in a Cork satellite town.

Residents in Glanmire are concerned the invasive plant’s infestation in the area could lead to a hold-up of planned flood prevention works, especially as the knotweed is visible appeared along sections of the Glashaboy River.

In particular, the plant has taken hold along the riverbank within the public-owned John O’Callaghan Park.

It sweeps especially from the deep pool area down to the weir where, in places, it has formed ‘hedging’ topping 10ft high.

The council has, in recent years, sprayed some plants in the area.

But, in other sections, the weed has grown dramatically and locals are concerned more infestation may occur as there are no warning signs advising the public the plant is dangerous.

However, interference with the plant can have implications for the control of the weed’s growth.

Locally-based county councillor Padraig O’Sullivan said, in Britain at present, insurance companies were not offering policies to homeowners in areas where the plant was found, primarily as it can damage and undermine buildings.

The councillor said he was keeping a close eye on the situation and he was also concerned there seemed to be no definitive policy in place by the local authority to tackle the problems.

Cork Co Council, it emerged, has asked its Environmental SPC (Special Purposes Committee) to draw up a plan to tackle the plant countywide.

Council chiefs have admitted they do not have the resources to tackle the growth of the knotweed which is noticeable along many public roads, the countryside, towns and villages.

It has called on the government to provide special grants to ensure its destruction.

Experts insist it can take up to three years to destroy the plant as it has to be treated on a regular basis to stem growth and kill the roots.

Cutting it is lethal, some experts also claim, as small slivers carried on the wind can quickly regenerate into new plants, spreading the problem further afield.

“It has become a serious problem in Britain and I hope it will be treated with the intensity it deserved in the Glanmire area,” said Cllr O’Sullivan.

Meanwhile, the flood prevention project is being led by Cork County Council in association with the Office of Public Works (OPW).

The county council’s project manager, acting senior executive engineer Colm Brennan said the local authority had been treating Japanese Knotweed in the Glanmire area for the past two years.

Treatment of the plant, he said, was primarily in the area where flood prevention works were due to take place. He said the council was designating, as a priority for treatment, riverside areas where embankments and walls are to be erected.

“It shouldn’t slow down the delivery of the flood prevention scheme,” he advised. 

“We will treat it in the John O’Callaghan Park and in some more areas around Glanmire.”


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