Managing invasive species at a Wastewater Treatment Plant in Co. Cork

A major infestation of japanese knotweed was an unexpected surprise for the construction team working on the new wastewater treatment plant in Riverstick, Co. Cork. Rivus designed an underground barrier to prevent the spread of the plants' root networks and ensure works could proceed.

The Problem

Construction had already begun on the wastewater treatment plant at Riverstick, Co. Cork, when japanese knotweed was discovered on site. There was a significant risk of the knotweed spreading throughout the entire site and potentially off-site too. At the time, there was no plan in place to deal with the problem.

Japanese knotweed growing alongside the road at the entrance to Riverstick Wastewater Treatment Plant

Japanese knotweed growing alongside the road at the entrance to Riverstick Wastewater Treatment Plant, prior to construction

The Rivus Solution

Rivus surveyed the site and the potential risk areas, including a nearby bridge structure that had knotweed growing through its foundations. We implemented herbicide programme, based on recommendations from our Registered Pesticide Advisor, to treat the invasive species. It was impossible to dig up all the knotweed in the area, as it was underneath the road and in neighbouring land. Instead, we designed an anti-invasive barrier that was placed underground along the site boundary to prevent the spread of root networks back into the site. We also supervised works to place all the contaminated material in a sealed receptor cell. We then monitored and treated any subsequent growth for three years post-project.

The Result

Our work minimised the risk of spread within the site and ensured that the integrity of bridge was preserved. The contractor is now aware of the potential biosecurity risks for future sites.

WANT TO KNOW MORE ABOUT THIS PROJECT? CONTACT SIMON FURNEY

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