For those in peril of the rising sea

28 Oct 2021 Nick Garbutt    Last updated: 28 Oct 2021

Many of us feel overwhelmed by the climate crisis, helpless at the scale of it, unsure of what we can do, and yet shocked by the complacency of some and terrified by the apocalyptic pronouncements of others.

It is a global problem and that can lead to some believing, especially in a very small place like Northern Ireland, that whatever we do will not make any difference.

The complexity of the issues at stake acts as a barrier to understanding, and if we do not know what is required and why. it is very hard to mobilise public support for change. And public support is necessary given the inevitable costs and lifestyle changes that reducing global warming demand.

But if we look at some of the specific impacts of global warming on a local scale we can start to see what needs to be done and how local policies can have an impact. We live on an island and have a beautiful coastline so coastal erosion is as good a place as any to start.

Much public debate has been about how we limit global warming to 1.5C, rightly so. Just as important is what we can do to adjust and adapt to the impact warming is having and will continue to have. Dealing with coastal erosion comes into this second category.

Global warming has two major repercussions for our coasts. The first is rising sea levels and the second is increasing instances of extreme weather the most relevant of which for coastal communities is stormier seas.

Historically coastal erosion has not been a major problem in Northern Ireland. This is because, strange as it may seem, the land is actually rising.

During the Ice Age the northern part of the island was covered by a massive sheets of ice up to three kilometres thick. This literally pushed down the land beneath, causing it to sink. After the ice melted, the land slowly started to rise again and as a result the area around Belfast is rising up at around 0.4 mm per year.

This serves to slow but not stop rising sea levels - the sea is rising at a rate of 3.4 mm per annum around the Irish coast, meaning that our net rise in levels is around 3 mm per year.

A further protection is the geology of our coast. Scientists state that the two highest categories of erosion risk are associated with the two youngest ages of sedimentary rocks. In Northern Ireland, these ages of rock are only present on the coastline from Cushendall to Belfast.

All this means that we are in a much better place than England, for example, where 7,000 homes are at risk of falling into the sea and 520,000 in danger of coastal flooding by the end of the century without intervention.

Here 20% of our coast is under threat, a manageable figure.

However the dreadful storms of January 2014 which saw widespread devastation, including the destruction of a section of the main coast road on the Ards peninsula outside Ballyhalbert was a wake-up call.

It raised attention to the growing threat and served to highlight that for more than half a century there is no legislation in place in Northern Ireland to either address coastal erosion or assign responsibility for it.

Instead it is dealt with by the “Bateman Formula” which was brought in in 1967 by Sir Cecil Bateman, then Permanent Secretary of the Ministry of Finance in the old Stormont regime.

This gives responsibility to protect at risk properties on the coast to the government department whose remits are most relevant to the properties concerned.

Therefore there is no overall strategy to manage coastal erosion – instead a patchwork of authorities from DEARA and DFI to local authorities are left having to protect their properties with no requirement to consider how their interventions effect those of others.

So for example if a sea wall is planned in a particular location you should really be factoring in the impact this will have further along the coast. And as we share an island and the sea does not respect political boundaries we should also be considering the impact of measures taken on either side of the loughs Foyle and Carlingford.

This lack of co-ordination needs to be fixed and appropriate legislation introduced.

But a new approach also needs to look at how we deal with what will be an increasing threat.

The traditional method has been to “hold the line” - building sea walls along the shore and groynes on the beaches.

However, as the sea continues to rise these measures ultimately fail and the defences need to be rebuilt and every time this happens the new structures are even more prone to fail.

An alternative approach is to work with nature. An example is regenerating sand dunes, which are an effective natural barrier to the encroaching sea.

Whilst natural techniques are being increasingly deployed in other parts of the world they will still not be enough. In England some authorities have conceded defeat to holding the line and are adopting a managed retreat from the advancing waves. In both parts of Essex and Sussex land at risk of erosion is abandoned because it is no longer considered economically viable to protect it.

In America and parts of the Caribbean they go even further. In vulnerable coastal areas they calculate how far back the shore will erode in the future. This determines where new buildings and roads can be built with construction banned in the buffer zone, eliminating the need for sea walls.

Closer to home the National Trust – which manages 108 miles (22%) of Northern Ireland’s coastline is advocating a fresh approach. Its seminal Shifting Shores report concludes: “as a nation we can no longer rely solely on building our way out of trouble on the coast…Where we can, recreating a naturally functioning shoreline will free us from the sea defence cycle of construct, fail and reconstruct.”

Coastal erosion due to rising sea levels is only one of many threats posed by climate change. It will be an increasing problem in the years to come, but there are ways of reducing its impact on our lives. Measures can and must be taken by our executive to construct a coherent strategy, introduce legislation and prepare for what is to come.

It should be noted that erosion is just one of 61 opportunities and risks which climate change poses to Northern Ireland. There’s a lot to be done.




Join the Conversation...

We'd love to know your thoughts on this article.
Join us on Twitter and join the conversation today.

Join Our Newsletter

Get the latest edition of ScopeNI delivered to your inbox.