'Natural flood prevention' plan proposed for East Cork town 

Carrigtwohill plan includes directing water away from properties into underground storage tanks and onto earmarked green spaces to be deliberately flooded in emergencies

As well as previous devastating floods in Carrigtwohill, Co Cork, the 'work in progress' flood plan by McCloy Consulting comes against the background of zoning being approved for up to 4,000 new homes. Picture: Denis Minihane

A rapidly-growing East Cork town is to get “natural flood prevention solutions” in a bid to avoid future disasters amid rising concern about the impact of climate change.

McCloy Consulting has drawn up plans to protect Carrigtwohill from floods, which include installing channels to direct water away from properties into underground storage tanks and onto earmarked green spaces that will be deliberately flooded during emergencies.

While the outline of the plan has already been developed, the details are a “work in progress”, especially as Cork County Council has approved zoning for up to 4,000 new homes on the northern side of the town’s railway line.

The plan is to channel overflow water from the four streams/rivers “into managed temporary inundation of green spaces and from these and other flood-prone areas also into underground concrete storage tanks”.

There is also a possibility that stormwater will be channelled into Slatty Pond, an area on the southern side of the town close to Fota Island.

The consultants say they will plan for “a flexible approach, delivering catchment resilience to the changing climate, using nature-based solutions”.

To date, they have carried out flood risk assessments in the area, drawing from previous flood flooding events, and will assess ways to protect new homes and expected further commercial and industrial development.

Carrigtwohill suffered extensive flooding last year during Storm Babet, with residential, community, and commercial properties severely damaged.

Consultants confirmed the project will be the first rainwater management plan to be undertaken in the country under a new national strategy and guidance for local authorities.

The Carrigtwohill Rainwater Management Plan contains analysis of previous floodwater routes and will concentrate on these for solutions to protect existing properties and design likely rain runoff patterns for planned developments.

Plans are also being drawn up to ensure the railway line and the adjacent pedestrian/cycle corridor are protected from flooding.

The consultants, who laid out preliminary plans for the project to local councillors, said they did not yet have an exact timeline for its implementation.

Carrigtwohill-based Fine Gael councillor Anthony Barry has expressed concerns about the preliminary report. He said its focus seems to be primarily on slowing the volume and flow of water to the culverts in and around Carrigtwohill by natural methods.

Mr Barry said: “This is fine but will in no way succeed in stopping a repeat of the events of Storm Babet." 

The culverts will have to accommodate increased capacity in conjunction with the proposed measures. Also, the study area doesn’t include large areas of land to the north and east of Carrigtwohill. 

He is also concerned Slatty Pond will not have the capacity to act as a storage area for extreme rainfall run-off.

Fianna Fáil councillor Sheila O’Callaghan said there is a reason the town got its name. She said it refers to two hills overlooking the town which “have a funnelling effect” into the urban area. Like Mr Barry, she said significantly enlarging existing culverts has to be considered in the overall plan, as the current ones are not fit for purpose.

The consultants said the project will be implemented in stages and over a number of years as the town grows.