As the Deputy will be aware, Japanese knotweed was first introduced to Ireland over 100 years ago. It forms dense thickets along roadsides, waste-grounds and waterways, reproduces by vegetative means and is difficult to kill off once it becomes established. This plant is included among the list of the 100 most invasive alien species of the world.
I am assured that Waterways Ireland takes the presence of Alien Invasive Species (AIS), including Japanese Knotweed, extremely seriously and is actively working towards the prevention, early detection and eradication of AIS along the various navigations.
In relation to the Deputy's specific query, I am advised that following the recent relining works on Level 6 of the Royal Canal, some knotweed was found on the newly landscaped soil. On foot of this discovery at the initial stand near the approach to the lock gate, operational staff of Waterways Ireland carried out systematic spraying of the infected area at the Lock and another section of knotweed on open ground at the opposite end of Level 6 beyond Coke Ovens Cottages (which was not connected to the relining works). On a follow up site visit on 11 September 2013, it was observed that the small stand of knotweed at the edge of the water had been eradicated by the effective spraying regime. I am advised that Waterways Ireland staff will continue to monitor the area for any reoccurrence of the infestation on its property.
The Deputy will also be aware that a wall separates the canal property from Irish Rail property and material overhanging the wall has recently been trimmed due to the impact on members of the public on the canal towpath. I should say that Waterways Ireland’s operational staff will systematically and safely spray and eradicate any identified patches of knotweed found on the canal property. It may also be noted that training in the identification, suitable control and management of AIS is given to Waterways Ireland's operational, technical and engineering staff as part of their regular tool box talks.
I am advised that Waterways Ireland works very closely with Inland Fisheries Ireland in the control and management of AIS, particularly aquatic species, including research into new methods of control. Waterways Ireland also works with Invasive Species Ireland and other relevant bodies in the dissemination of information and practices in the control of AIS and will continue to liaise with Irish Rail to devise a management plan for AIS in areas of common interest.