As the Deputy is aware, Dúchas, the heritage service of my Department, is responsible for navigation on the River Shannon and one of its principal duties is to ensure that there is adequate water depth for the navigation of boats on the system. This activity applies almost exclusively to the cruising season, from mid-March to October, as only a few hundred of the 75,000 boat passages through the locks annually occur during the winter months.
Water levels in the three main lakes on the river – Loughs Allen, Ree and Derg – are controlled by the ESB. Water levels-depths in the river between these lakes are controlled by Dúchas for navigation purposes by means of a series of weirs with sluices.