Claire Kerrane
Question:197. Deputy Claire Kerrane asked the Minister for Public Expenditure and Reform the plans the OPW put in place for flood relief in the Shannon Callows for 2020. [40965/20]
View answerThursday, 3 December 2020
Questions (197, 198, 199)
Claire Kerrane
Question:198. Deputy Claire Kerrane asked the Minister for Public Expenditure and Reform the plans the OPW is putting in place for flood relief in the Shannon Callows in 2021. [40966/20]
View answerClaire Kerrane
Question:199. Deputy Claire Kerrane asked the Minister for Public Expenditure and Reform if the maximum amount of water has been safely released without flooding communities at Parteen Weir and Ardnacrusha in order to lower Lough Derg in anticipation of the next weather event. [40967/20]
View answerWritten answers
I propose to take Questions Nos. 197 to 199, inclusive, together.
The Government established the Shannon Flood Risk State Agency Co-ordination Working Group in 2016 to enhance the ongoing co-operation of all State Agencies involved with the River Shannon. It is co-ordinating the overall response to flood risk management on the Shannon informed by the assessment of flood risk carried out under the Catchment Flood Risk Assessment and Management (CFRAM) programme and it is taking forward other initiatives to mitigate flooding on the Shannon.
Since its establishment, the Group has produced annual work programmes, which include co-ordinated focussed and prioritised actions and activities to manage flood risk for the Shannon catchment. The work programme for 2020 is published and available at www.opw.ie. Preparation is currently underway for the work programme for 2021, which will be published following its approval by the Working Group.
The Group has taken a number of significant decisions since its establishment and the scope of work undertaken to date includes:
- Completed targeted maintenance at five locations on the River Shannon which has enhanced the conveyance capacity and halted further deterioration of the channel.
- Completed a study to examine the removal of constrictions resulting in lower summer water levels through the Shannon Callows, to help address the summer flooding in the area while maintaining the appropriate navigation requirements.
- Completed a study to examine the cause, degree and rate of restriction downstream of Parteen Weir in the Lower Shannon.
- Trialling the lowering of the lake levels on Lough Allen to help alleviate any significant flooding that may occur.
- Completed a preliminary assessment on the potential for strategic maintenance on the River Shannon.
In October 2019, the Group agreed to a €7 million strategic programme of maintenance works and the removal of constrictions or ‘pinch points’ on the bed of the River Shannon between Athlone and Meelick Weir, through the Callows region, to improve the conveyancing of the River Shannon. This work will involve the full environmental assessments required to progress to the planning process for consent to proceed. This may influence the order of priority for undertaking the proposed works by Waterways Ireland, as the implementing body for the works. The works will also be informed by public consultation.
Waterways Ireland has informed the OPW that it is advancing the various interventions, with work expected to commence at a number of locations in 2021.
The ESB manages the weirs, sluices and other works that are part of the Shannon Scheme, and the water levels on Lough Allen, Lough Ree and Lough Derg. The levels in between the lakes are managed by Waterways Ireland for navigation purposes. Both organisations are members of the Working Group and communicate on a daily basis to ensure a co-ordinated approach to managing water levels on the River Shannon.
I am informed by the ESB that it is continuously monitoring the water levels throughout the Shannon Catchment and continues to operate in accordance with its regulations and guidelines for control of the River Shannon. In times of flood, ESB prioritises the safe passage of water over the generation of electricity. There has been less rainfall over the past week throughout the catchment following a sustained wet period. This has resulted in a reduction in water levels in the River Shannon and its tributaries. Lough Derg levels have reduced to within its normal operating band.
Discharge at Parteen Weir down the old River Shannon Channel was reduced on Monday 30th November from 55m3/s to the statutory compensation flow of 10m3/s. Ardnacrusha Station is operating at full throughput; that is discharges are 350-400m3/s. Discharging more water than current would result in lowering water levels in Parteen Basin below safe operating limits with the risk of causing stability issues to the Earthen Embankment Dams that form Parteen Basin. ESB can only manage the flow of water as it arrives at Parteen Weir from Lough Derg. The water flow from Lough Derg to Parteen Basin is restricted by the flow capacity of the outlet channel from Lough Derg at Killaloe. The capacity restriction acts like a bottleneck limiting the discharge from Lough Derg. ESB is maximising the discharge of water from Lough Derg within the Dam Safety constraints.
Should further rain occur, water levels in Lough Derg will rise, which will result in increased water flow to Parteen Weir; that situation will necessitate further discharge from Parteen Weir down the old river Shannon channel. Predicted water levels and expected discharge amounts based on the latest Met Éireann forecast can be found on the ESB’s twice weekly Shannon Forecast available to view at: www.esb.ie/our-businesses/generation-energy-trading-new/hydrometric-information/river-shannon.