Climate change will have a significant impact on flood risk in Ireland. It is projected that the number of heavy rainfall days per year will increase, which would lead to an increase in flood risk. According to Met Éireann data, July 2023 was the wettest July that has ever been recorded, with prolonged heavy rainfall on 14th and 15th. July 2023 also had more than four times the amount of rain observed in July 2022 and more than twice that observed in July 2021.On a day to day basis, water levels on the Shannon River are managed in accordance with agreed protocols between Waterways Ireland and the ESB. The OPW has no role in the operation of sluice gates.The ESB and Waterways Ireland are in continuous communication and coordinate management of the eight sets of sluice gates impacting on water levels on the lake and river sections of the Shannon, seven days a week. Waterways Ireland and the ESB proactively monitor weather forecasts and use water level reading instrumentation to make informed decisions around sluice opening and closing procedures, whilst adhering to protocols agreed with the ESB.
Waterways Ireland have advised that on the 6th of July water levels recorded showed the water level 60mm below ordinary summer level at Banagher and 190mm below ordinary summer level upstream of Victoria lock. Waterways Ireland had 2 sluices open at both Meelick and the New Cut.
Waterways Ireland was aware through monitoring of weather forecasts that heavy rainfall was predicted. In anticipation of this and over the week commencing the 10th of July Waterways Ireland opened an additional 4 sluices in both Meelick and the New Cut on the 10th of July and an additional sluice at Meelick and 2 additional sluices at the New Cut on the 14th of July.Water level readings taken on the morning of the 14th showed the level in Banagher 70mm below ordinary summer level and upstream of Victoria Lock showing a level 340mm below ordinary summer level. Intensive rain fall began on the 14th July across many parts of Ireland. In response Waterways Ireland opened the following sluices over that weekend period:• 14-07-2023 – 2 sluices opened at the New Cut.• 15-07-2023 - 6 sluices opened at the New Cut. (Over two visits)• 15-07-2023 – 4 Sluices opened at Meelick Weir.(Over two visits)• 16-07-2023 – 1 Sluice opened at Meelick Weir.• 16-07-2023 – 2 Sluices opened at the New Cut.No further interventions could be undertaken by Waterways Ireland as all sluice were open from the 16th. Simultaneously to this the ESB closed all sluices on Athlone weir on the afternoon of the 14th July to limit the volume of water entering the Callows area. On Sunday, the 16th Water level readings taken at Banagher were 250mm above ordinary summer level with Victoria Lock upstream reading 210mm below ordinary summer level. This sluice arrangement remained in place until water levels had receded back to Ordinary Summer Level.
These operations influence the levels on the Shannon but due to the shallow gradient of the river and the many natural restrictions along its course, the levels cannot be fully controlled especially when the Shannon is in flood. The river level is primarily the result of the amount of rain that falls on the river catchment area. When all sluice gates are open, there is no further action available to prevent further rising water levels. Possible approaches to provide a long term solution to summer flooding in the Shannon Callows are being developed by the Shannon Flood Risk State Agency Co-ordination Working Group. This Group, which is chaired by the OPW, provides a forum where all statutory organisations with roles and responsibilities that involve the River Shannon catchment can further monitor and co-ordinate their respective work programmes to assist with managing flood risk along the Shannon catchment.Flood risk to communities on the River Shannon and elsewhere is being addressed through flood risk management plans. Flood relief schemes are the primary means of protecting cities, towns and villages from flooding. There are currently 13 completed schemes in the Shannon River Basin District and these schemes are already providing protection to over 2,600 properties. A further 36 flood relief schemes will be delivered as part of the Government’s €1.3bn investment in flood relief measures over the lifetime of the National Development Plan to 2030. 24 of these schemes are currently being progressed including Athlone and Springfield which are currently are substantially complete.A full list of flood relief schemes in the Shannon River Basin District is available here: www.floodinfo.ie/scheme-info/?r=7
