We have had very pleasant, dry weather in Galway while the east of the country suffered under a deluge. It does give us pause for thought about whether Galway is ready for the inevitable increased rainfall.
Most of the flooding in Galway has historically been driven by storms that coincide with high tides. This is the hazard that is being addressed by the ‘Coirib go Cósta’ program which is proposing walled flood defences for some of the coastal areas of Galway City.
The flood defences do not address the issue of how surface rainwater is managed. Ideally the network of storm drains directs water to the Corrib or the sea. However, for historical reasons, the storm drains are interconnected with sewage drains. And the sewage drains are limited by the capacity of the pipes and the capacity of Mutton Island. During high rainfall events we already discharge the sewage and rainwater mix into the sea near the long walk. Apart from this pollution risk, if we get higher volumes of rainfall then there is a risk that the drains back up, causing localised flooding. It is very difficult to predict which areas might be at risk, especially when storm debris can cause a temporary blockage.
We absolutely need Uisce Éireann to upgrade the capacity of the sewage system – something that was needed to support new housing developments even before we consider the rain hazard – but there was a lack of funding for this in the recent National Development Plan. Galway needs to be sure that the OPW, City Council and Uisce Éireann are all sharing a view of dealing with flooding, and are funded accordingly.
The city council do deserve credit for incorporating a rain garden into recent road improvements at Sea road. It is vital that some of the water soaks into the ground in order to reduce the volume that enters the city’s drains. This project is only one small step on the path to improving the city’s ability to soak up some of the rain.
Another contributor to flooding is the planning decisions we make. Last year, while updating the city development plan, councillors voted to rezone to residential use in four locations which were on flood plains, against the advice of the city engineers. The Green Party and Social Democrat councillors were consistently opposed to such decisions, but were heavily outnumbered in votes by other councillors.
ortunately the minister for housing overturned four of these decisions, and those lands will not be built on and will continue to provide a buffer against future flooding. The next revision of the Galway City Development Plan will be drafted over the next two years. It is way past time that we listen when the engineers say ‘Don’t build on flood plains’.
