November 2009 Galway and Western Floods

The same Atlantic weather system that triggered the Cork floods — the remnants of Tropical Storm Ida fused with a deep European low — swept across Ireland from southwest to northeast over 18–21 November 2009. The system was unusual in its breadth: rainfall totals exceeding 70 mm in 24 hours were recorded at multiple stations across Connacht and the Shannon basin.

Soil saturation across the west was extreme after a wet autumn. The Corrib system, which drains a large and already-saturated catchment including Lough Corrib — one of Ireland's largest lakes — responded rapidly to the rainfall input. The Shannon catchment, already running high after weeks of wet weather, could not absorb further rainfall and began spilling into low-lying farmland and settlements.

Galway city experienced significant flooding in the Claddagh and Salthill areas as the Corrib system reached high levels. Numerous roads across Galway, Mayo, Roscommon and Leitrim became impassable. Flooding of the N60, N63, and N17 effectively cut off large parts of Connacht by road.

The Shannon Valley saw widespread flooding from Lough Allen in Leitrim south through Roscommon, Athlone, Portumna and into Clare. Farmland was extensively flooded for weeks. Many rural homes in low-lying areas adjacent to the Shannon floodplain were inundated. Turloughs — the unique seasonal lakes of the Burren and Galway limestone landscapes — filled rapidly and expanded beyond their normal seasonal extent.

The event coincided with Cork and drew less national attention, but its economic impact on rural communities and agriculture across Connacht was significant. The Irish Farmers' Association estimated agricultural losses across the west at several tens of millions of euro.

Flooding in the Shannon callway persisted for several weeks after the initial November event, as the vast Shannon catchment drained slowly through the winter. Some roads remained closed well into December. Agricultural damage was extensive and many farmers received emergency payments through the EU Solidarity Fund.

The 2009 western floods contributed to the political pressure that eventually led to the Shannon CFRAM study and the development of a Shannon Flood Risk State Agency Co-ordination Working Group, which brought together the ESB, Waterways Ireland, the OPW and local authorities to better coordinate management of the Shannon in flood conditions.