Neasa Hourigan (Dublin Central, Green Party)
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154. To ask the Minister for Public Expenditure and Reform if his Department still supports the statement in the environmental impact assessment report to the River Bride (Blackpool) certified drainage scheme that flooding in Blackpool is primarily fluvial; if restricting the river channel in Blackpool by constructing hard flood defences will also restrict pluvial flow; if the scheme has been designed to meet the risks presented by pluvial flooding events, such as that of October 2022; and if he will make a statement on the matter. [21395/23]

Patrick O'Donovan (Limerick County, Fine Gael)
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Blackpool has a history of flooding and whilst not limited to river (or fluvial) flooding, the vast majority of major flood events have been due to river flooding. The primary purpose of the River Bride (Blackpool) Certified Drainage Scheme (Flood Relief Scheme) as described in the EIAR (Environment Impact Assessment Report) is to address fluvial or river flooding. The proposed Scheme does not propose to restrict the river channel but will increase the capacity in many areas by removal and ongoing management of sediment load, reduction of debris risk through addition of trash screens, and removal of local throttles at some undersized bridges. The purpose of the direct defences is to provide protection to properties and businesses and the road network.

Pluvial flood risk by definition arises when rainwater either cannot reach the drainage system or exceeds the capacity of the various gullies and surface water drainage elements, i.e. before it ever reaches the river system. The surface water drainage system in and around Blackpool is a combination of combined sewers, now managed by Uisce Éireann, and some discrete surface water systems which are the responsibility of Cork City Council. Uisce Éireann is currently finalising a detailed Drainage Action Plan for the area, following which, the need for any drainage network upgrades may be identified. OPW and Uisce Éireann are liaising closely so that the information and knowledge gained from both projects is shared and any opportunities for synergies can be determined.

Whilst the Blackpool Flood Relief Scheme does not seek to address drainage network capacity issues throughout the catchment, like all OPW flood relief schemes, it does include measures to ensure that pluvial flood risk immediately adjacent to the river corridor is not worsened and if possible is reduced. This will be achieved by including local pumping stations at the outfalls from the drainage systems into the river to ensure that the surface water can still be discharged even when river levels are high during river floods. In addition, in areas where construction works for the flood relief scheme are taking place, the reinstatement works will include local improvements to drainage features such as kerb lines, gullies, pipe replacements which details are being finalised in close collaboration with both Uisce Éireann and Cork City Council.