Mr. John Hegarty:

Save Cork City is a voluntary group. We started in January 2017 because we were concerned about the impact of the lower Lee flood relief scheme and that the majority of people in the city know nothing about the proposals for walls as flood defences within the historic centre of Cork. The Arterial Drainage Act has been used as a vehicle to implement the proposals, leaving many people uninformed.

We have found that, while everyone in Cork wants flood relief, most do not want the type of flood relief presented by the walls scheme. We also found that the OPW proposal had not adequately considered the negative impact of the walls on the environment of the city. The historic defences are an irreplaceable element of the character of the city. The walls scheme was designed as an engineering solution only and with little consideration of other issues.

The OPW's economic impact assessment of the walls scheme is inadequate and the cost-benefit analysis excludes economic loss suffered by businesses during construction as well as the long-term impact on the local economy. We found that many of those who supported the walls scheme were in fear of losing flood prevention funding. People had often been told by the OPW that the walls scheme was the only possible solution and that a barrier would be too expensive. The OPW's estimate of €1 billion for a tidal barrier was an exaggeration of cost for an outline and impractical solution involving two barriers on either side of Great Island. This was based on a 350 m tidal surge gate in Rotterdam from the 2014 rivers document, which also recommended a no-walls solution generally in Ireland.

We decided to investigate a more economical design and location for a tidal barrier for Cork. An independent report commissioned by us from HR Wallingford, experts in tidal barriers and climate change, has found that a barrier can be built for €140 million, approximately the same figure as the current walls proposal.

We are convinced that the walls would severely affect the local economy of the city, represent a significant waste of public funds and potentially be a dangerous flood relief solution for Cork. We want the right flood protection for the city and the River Lee. We want a solution that is climate change resilient and protects our valuable heritage. We call on the Government to adopt our proposals for flood protection and to investigate this matter in the national interest.

The walls scheme would lead to the mass destruction of significant, antique and rare items of heritage throughout the historic core of Cork city. Loss of heritage would affect the city's ability to attract investment and tourism as well as diminish the environment for those who live in the city and have already invested there. The World Bank states: "A city’s conserved historic core can also differentiate that city from competing locations - branding it nationally and internationally - thus helping the city attract investment and talented people." It also states: "In addition, heritage anchors people to their roots, builds self-esteem, and restores dignity."

Traffic diversions, dust, noise and the closing of roads and bridges would cause serious loss to the local economy during proposed construction of the walls. Many of our local family businesses would not survive the construction impact of the scheme. The factors of unmapped water mains and cables and unknown underground conditions within the city centre would lead to significant delays and budget overruns.

A tidal barrier report was commissioned by Save Cork City to determine the suitability of Cork for a tidal barrier and provide a reasonable cost estimate. It has been prepared by Mr. David Ramsbottom and Mr. Peter Hunter of HR Wallingford, international experts in flood management. Both authors have vast experience in flood relief and tidal barriers, having worked on the Thames, Cardiff and St. Petersburg barriers. The report reads:

The estimated cost of the barrier at 2017 prices is €140 million.... There is no doubt that a barrier could be built at the proposed location.... The alternative scheme [of the tidal barrier] has the major benefit of not requiring the construction of walls along the quays in the city ... the [tidal barrier proposal] would also avoid the scenario of overtopping or failure of flood walls in the city, which would cause a serious risk to life as well as damage to the city."

The report predicts that the tidal barrier could cost more or less than the €140 million figure, or between €110 million and €170 million.

HR Wallingford is a world leader in hydrology and climate change. The authors of the report have a combined experience of 80 years. They have studied the upstream conditions of the River Lee following the 2009 flood event that caused so much damage in the city. It is with this knowledge that they have written their report. The overwhelming evidence supports a tidal barrier solution at Little Island. HR Wallingford believes that the tidal barrier would minimise environmental impact on the river and avoid failure of flood walls.

According to Mr. Ramsbottom, the alternative solution for flood protection in Cork is viable and would have the major benefit of minimum disruption in the city. A tidal barrier is an effective means of preventing tidal flooding and providing storage for fluvial flooding, which would work in combination with dam management to protect the city.

In the OPW's walls scheme, all of the historic quay parapet walls of Cork's historic centre are proposed to be removed down to the current ground level. The walls scheme facilitates higher flood water levels that are above the ground floors of people's homes. This represents a new and dangerous precedent for the city and the people who know about it do not want it.

The walls scheme relies on extensive grouting with concrete by excavating miles of trenches and filling behind every quay wall in the city centre. We have witnessed that flooding comes up through the ground and drains in the city. What the OPW proposes would not be achievable and we are advised that it would dramatically affect the city's water table. It is like trying to stop time. This could lead to the widespread subsidence of historic buildings, alterations to the water table in the city and an increase in water levels and speeds in the river.

The walls scheme proposes 46 pump chambers to keep the city behind the walls from filling up like a bowl of water. The scheme proposes more than 8 km of walls and embankments. In the historic city, the OPW scheme includes 22 pump chambers and 5.7 km of concrete walls of varying height and width.

The HR Wallingford report makes a grave statement relating to the safety of the walls scheme where it outlines clearly that the tidal barrier solution would "avoid the scenario of overtopping or failure of flood walls in the city, which could cause a serious risk to life". The walls scheme has been highlighted by the HR Wallingford report as being a potentially dangerous solution.

The Dutch say that, when considering flood walls, it is better to choose the shortest form of defence, as it is easier to predict the outcome, more economical to construct and maintain and significantly less likely to fail. We refer the committee to Edgecumbe in New Zealand, which flooded extensively in April due to a small breach in a walls-based flood protection system. We also refer to New Orleans in 2017, which flooded due to its pump system not starting when required.

The walls scheme would cost much more than estimated based on the complexity of the proposal. The tidal barrier would protect far more of the city's area than the walls scheme would. If the walls scheme had to extend to cover the same area as the tidal barrier, it would cost more than €500 million.

A tidal barrier is a predictable, defined project in a defined place. Construction of a barrier, if managed correctly, provides certainty and predictability of outcome, including how much it would cost and how long it would take to build. The independent HR Wallingford report confirms this. A tidal barrier would protect vast additional areas of the city, including the docklands and vital infrastructure of roads and rail routes. Without the protection of a tidal barrier, the development of Cork's docklands is not economically viable.

Litigation arising from damage to property is inevitable if the walls scheme proceeds in the historic city. In addition, rebuilding the quay walls and cast railings that are proposed to be removed would cost hundreds of millions of euro. It would be like throwing out the family silver.

A tidal barrier could be constructed in two years following site investigation and design. It is a faster form of flood relief than the walls proposal. A tidal barrier is environmentally a better choice for Cork. This solution promotes slowing the absorption of rainwater into the landscape and thus slowing the flow of the river. We promote a more biodiverse landscape and better soil quality. The HR Wallingford report reads: "A tidal barrier is the preferred choice for Cork because the present tidal regime is maintained and the impacts on navigation, drainage, morphology, saline intrusion, water quality, fish passage and the environment are minimised by the barrier." We believe there to be a greater environmental impact from a walls-based scheme. We note the significant number of mature trees that would be lost in the city as well as the widespread disturbance of habitats and pollution on the river.

The tidal barrier solution can adapt to climate change, ensuring that Cork city would be safe for generations.

The walls scheme cannot adapt to sea level rise without significant use of demountables and-or major additional spending. The Thames Barrier has been closed 179 times since it became operational in 1982, protecting the city of London. Of these closures, 92 were to protect from tidal flooding and 87 to protect from combined tidal and fluvial flooding. These figures are from the UK Environment Agency.

HR Wallingford examined the upstream conditions of the River Lee following the 2009 flood event. It is with this knowledge that it has written its report. The Save Cork City tidal barrier location allows for the storage of water from upstream when the barrier gate is closed and thus the tidal barrier can protect against combined tidal and fluvial flooding. A recent proposal for a new form of dam at Dromcarra by Professor Philip O'Kane would add to upstream fluvial protection. The current upstream Carrigadrohid Dam, altered in 1991, may now be fitted with a responsive flood gate which would further increase fluvial protection for the city. The city is already protected from fluvial flooding and the capacity can be increased in many sustainable ways. The walls scheme actively facilitates increased water levels and increased flow rates in the river. The walls scheme promotes a dangerous, fast-flowing river in the city and considers the north channel of the River Lee as a drainage route. The OPW called the walls scheme "the Lower Lee (Cork City) Drainage Scheme" in its public consultation of December 2016.

We propose an economical tidal barrier for Cork in our solution document, Potential Cork, between Little Island and Horsehead on the edge of Lough Mahon. The 60 m wide gate is based on consultation with the Port of Cork authority. It referred us to the opening span of proposed bridges on the river at 50 m. By way of comparison, 60 m is also the width of the access gate in the Thames Barrier. The tidal barrier would allow for the development of the historic city centre in a manner that would give it a competitive edge and secure the well-being of residents and traders in the city. Repair and restoration of the historic quay wall defences combined with sensitive design addition would ensure that the city is viable socially and economically. Cork is a maritime city whose character has been influenced heavily by trading relationships with France and the Netherlands as well as the south of England. Many people came ashore in Cork and influenced the design of the city, where Cornish and French slate hanging, Dutch brickwork and Italian plasterwork are still in evidence.

The quay walls, railings and bridges of Cork allow for connection with the river, which is part of the daily lives of the people. The tidal barrier would allow for the maintenance of the historic quay walls in the manner of many historic European cities. We see this as a major advantage to Cork if it is to develop as a city capable of growing and attracting investment in the future. We believe that Cork's historic quays should be nominated for UNESCO world heritage status. We also believe that the OPW walls scheme contravenes the obligations of the Granada Convention. Liverpool's maritime port has UNESCO world heritage status. Cork was trading hundreds of years before Liverpool. The tidal barrier would mean faster flood relief for Cork and value for money for the taxpayer. The tidal barrier would allow the city to move forward now. Many improvements to the city and the river catchment can be achieved while a tidal barrier is being constructed. This is not possible with a walls scheme which may establish its goal only after six to ten years of construction.

The lack of investigation of a tidal barrier solution before now has let down the people of Cork. Years of pursuing a scheme that is not right for the city has delayed flood relief. The OPW should be considered protectors of our national heritage, not destroyers of it. The Save Cork City solution to flood relief works as part of an integrated flood defence system. It is the only solution for Cork if we are to have viable and extensive flood relief. A tidal barrier is the safest, most predictable, and most economical solution. It represents the best value for money. Our proposals are supported by academics and flood relief experts, flood defence agencies, environmentalists and many thousands of Cork citizens. Support for a tidal barrier is increasing in Cork and a forced walls solution would not represent fair play or fair local democracy. John F. Kennedy said: "An error does not become a mistake until you refuse to correct it." We formally thank our supporters here and thank the committee again for allowing us to present to it.