Clare River Flood Relief Scheme

Following extensive flooding in County Galway as a result of the November 2009 flooding event, a Joint Working Group, comprising of Office of Public Works (OPW) and Galway County Council officials was set up to identify flood mitigation measures for the region.

Ryan Hanley was commissioned to undertake a preliminary flood study of the Clare River. The study was prepared with the objective of identifying practical measures to address flooding on the Clare River and on its main tributary, the Abbert River, within a study area from Lough Corrib to Corofin in County Galway.

The Study recommended a major scheme of works on the Clare River in addition to advanced works including the construction of flood eyes at Crusheeney Bridge and one at Claregalway Bridge as part of a programme of viable measures to eliminate or reduce flooding from a similar sized flood event to November 2009.

Key Aspects of the Report include:

Flood Risk Assessment employing Hydrological and Hydraulic Analysis and Historical Flood Data Review
Community and Stakeholder Engagement through Public Consultations and Stakeholder Meetings.
Identification of Flood Mitigation Measures including both Structural and Non-Structural Measures such as embankments, flood walls, river channel modifications, and flood forecasting and warning systems.
Environmental and Regulatory Considerations.
Feasibility and Cost-Benefit Analysis evaluating the technical viability of proposed flood mitigation measures and ensuring that the proposed solutions provide value for money and are economically sustainable.

The Outcomes of the Report include:

Detailed Flood Risk Maps identifying vulnerable areas along the Clare River.
Proposed Mitigation Strategies tailored to the specific needs of the Clare River catchment area.
Enhanced Community Awareness through engagement and dissemination of information.
Foundation for Future Planning providing a robust foundation for detailed planning and implementation of a flood relief scheme project.

Project Details

The first stage of the project involved the construction of a flood eye at the N17 bridge in Claregalway. Three water mains (600mm, 250mm and 80mm diameters) traverse the location of the proposed flood eye. The 600mm diameter trunk water main supplements the Galway City Water Supply as well as supplying water to numerous towns and villages including Athenry, Oranmore, Clarinbridge, and Kilcolgan, and numerous group water schemes. The 250mm diameter water main supplies Claregalway and an area to the North of Claregalway which includes Slievefinn and Mullacuttra Group Water Schemes. The 80mm water main also supplies the Claregalway area, including two hotels. The purpose of this stage of the project was to construct temporary and permanent diversions of the 600mm, 250mm & 80mm diameter water mains to minimise the disruption of the water supply to the above-mentioned areas of County Galway during OPW construction works.

Additional works took place in parallel with this project including the diversion of the N17 National Primary Route via a temporary bailey bridge, installed to the West of the existing N17 bridge, and the construction of a flood eye to the South of the existing bridge. Consequently, the work was constructed in six consecutive sections to facilitate the parallel construction work.

The Ryan Hanley Study to identify practical measures to address flooding on the Clare River played a crucial role in shaping flood management strategies for the Clare River. By combining scientific analysis, stakeholder engagement, and sustainable planning, the study by Ryan Hanley serves as a critical foundation for developing and implementing effective flood relief measures on the Clare River, aiming to protect lives, property, and the environment from the impacts of flooding.