Wales underwater?

A map of Wales in the background with the text 'Wales under Water?' in the foreground, with small waves covering mid-Wales

The Wales of 2050 will be a very different place.

Our society, technology, culture and economy have always changed over generational timescales, so there’s nothing inherently original or insightful in my opening statement. However the changes to come will be manifestly different to those experienced by previous generations.

That’s because our current and future generations will experience profound geophysical changes, forcing society to react rapidly, and in some cases to discard long-loved, cherished and critical parts of our culture and infrastructure.

Sea level rise by 2050

Although it’s impossible to know which of drought, flooding or wildfires will bring most misery to Wales’ inhabitants by 2050 – and each of these are serious issues on their own merit – I hazard that coastal flooding exacerbated by sea level rise will eclipse all of them.

The latest data, published at the end of October, show graphically what happens to Wales’ coastal conurbations within the next generation. And the implications of this – the best of our global modelling on climate change impacts – deserves serious consideration within Welsh Government, within our local authorities and indeed by us as individuals, householders and communities.

The data is interpreted in a way that helps us understand the impact in a map format by Climate Central, an independent organisation reporting on the facts of climate change. The modelling is based on the most robust and evidenced data, and although the modelling outputs come with inevitable caveats, they are the best indication we currently have about coastal flood risk for Wales.

Whilst the modelling is highly customisable depending on your appetite for risk, the version I’ve used for this article is the central scenario for climate change, which incorporates:

  • ‘Average’ sea level rise plus annual flood
  • Moderate cuts to GHG emissions, consistent with 2 Celsius warming
  • Medium ‘luck’ (mid-range result from the range of possible projections of sea-level rise)
The model is highly customisable for your tastes

In the images that follow, anywhere coloured red is projected to be “below annual flood level” in 2050. That means that coastal flooding is anticipated to happen annually, with multiple flooding events also possible on an annual basis.

I’m going to take a place-by-place approach to the potential impacts, starting with my own hometown, Cardiff.


Areas of Cardiff which will experience coastal flooding on an annual basis by 2050 in red

By 2050, much of Cardiff’s urban area will be at risk of annual coastal flood events. Notwithstanding the resilience provided by the Barrage, coastal water ingress is likely to be an issue with much of the low-lying land along Cardiff’s wider seafront and the Afon Rhymni, leading potentially to widespread penetration.

Many of our institutions will have to consider how they manage this risk, including iconic landmarks such as Cardiff Castle, the Royal Welsh College of Music & Drama, the National Assembly, Sophia Gardens, the International Sports Village and the Principality Stadium.

The Bay and a huge swathe of West Cardiff, including Grangetown, Riverside and Canton, along with the city centre, Bute Park, and huge chunks of east Cardiff such as Roath, Adamsdown and Tremorfa are highlighted as facing significant flooding issues.

Nationally significant infrastructure such as major electricity substations and railway and road infrastructure is potentially at risk, as are the large chemical and industrial sites which lie along Cardiff Bay and the dock areas.


Newport's annual coastal flood risk by 2050

Newport’s famous hills, which provide spectacular viewpoints for the city and estuary and are a source of misery for casual cyclists, provide some resilience against coastal flooding.

Parts of the city centre, including the Royal Gwent hospital, escape the projected risk areas, but the Passport Office and Transporter Bridge, along with much of the riverside past Caerleon and beyond Newbridge-on-Usk fall into the annual coastal flood risk category.

The Gwent Levels along with several golf courses are at risk of regular inundation of salt water, with the natural habitat presumably being significantly more resilient than the leisure facilities.

Although not included in the image above, a large swathe of coastal land from Newport to Chepstow is at risk, including the whole of the mainline railway linking south Wales to Bristol and beyond.

The Vale of Glamorgan

The Vale of Glamorgan's flood risk by 2050

The Vale demonstrates more resilience than the coast further east, by virtue of high cliffs along much of the coastline. Penarth faces only a very modest impact at the harbour, but Barry Island, the docks and ports and the Dow chemical plant are all at risk. The danger zone for Barry extends along to Sully and up towards the lowest lying areas of Dinas Powys.

The most heavily industrial parts of the vale, including around the power station and cement works near Aberthaw are included within the at-risk areas.


Porthcawl's annual coastal flood risk by 2050

The misery of annual flooding for Bridgend County Borough appears to be concentrated on Porthcawl. The low-lying caravans of Trecco Bay are at risk, as are central residential areas of the town.

Neath Port Talbot

Flood risk for 2050 for Neath Port Talbot

The low coastline from Porthcawl to Swansea poses significant potential problems for transport infrastructure, as well as for some industrial and residential sites. Areas impacted include the Kenfig Industrial Estate, the Port Talbot town and the residential areas of Aberavon, Baglan Moor, along with the Tata steelworks.

The Afon Nedd carries the risk further upstream, potentially impacting settlements along the riverside in Neath itself, nearl as far as Aberdulais.


Swansea's annual coastal flood risk areas

The impact for Swansea is mostly felt around the lower part of the town – Sandfields and the Maritime Quarter – and at the new Bay campus to the east of the city. The Amazon distribution centre, along with incoming road and rail links could also be impacted.

Carmarthen Bay

The annual coastal flood risk areas around Carmarthen Bay

The estuary areas around Carmarthen Bay look particularly vulnerable, albeit in regions of low population density. The north Gower coast, along with swathes of the estuary ranging from Pontarddulais down to Pembrey and Kidwelly are at risk, as is the Pembrey West airport. The Afon Tywi is a flood risk factor for parts of Carmarthen and higher up the riverside. Further west Laugharne and St Clears are likely to be impacted.


A low coastal flood risk for Pembrokeshire

Pembrokeshire appears to be spared the worst of the coastal flooding risk, presumably because it has less land area at lower altitude than many other parts of Wales. The small but regionally significant populated centres of Pembroke and Haverfordwest will likely see some impact, and the campsite at Newgale – already a temporary lake-site during times of heavy rain – will be hit hard during high tides and storms.


Ceredigion's annual coastal flood risk

Whilst the southern part of the county escapes the worst of the coastal flood risk, the north will probably take quite a hit. Lower Aberystwyth, from the harbour up to Glanyrafon, could potentially be inundated, causing problems for transport infrastructure and for regulators and officials in Welsh Government and Natural Resources Wales.

Borth - a grim prospect by 2050

Borth is predicted to be particularly vulnerable, with the whole village – and the estuary right up to Machynlleth- predicted to flood on an annual basis. On the other side of the estuary (and into Gwynedd), Aberdyfi and Tywyn also face huge challenges.

Gwynedd and Ynys Môn

Gwynedd and Ynys Mon

Both these iconic counties face probably localised problems with coastal flooding in the decades to come.

Gwynedd’s problems are in pockets in the south (Aberdyfi, Tywyn) and west (Porthmadog). Môn’s issues will be felt strongest along the Afon Cefni, and in lower lying areas around The Valley in the west.


Conwy's annual coastal flood risk in 2050

The risks for Conwy are centred on the Afon Conwy, which could bring coastal floods upstream as far as Llanrwst, Llandudno, and the low-lying areas to the west of the Afon Clwyd. Large areas of agricultural land, as well as numerous coastal communities in this area and regionally significant transport and health infrastructure are vulnerable.


Denbigshire's flood risk

Denbighshire has a short coastline, but it is low-lying, and therefore all modelled as having a very high risk by 2050.

The communities of Rhyl and Prestatyn face severe hardship from the impact of coastal flooding on an annual basis in the absence of any major infrastructure to provide coastal protection.


Coastal flood risk for Flintshire

Flintshire’s coast is also modelled as having severe risk. Potentially significant energy and industrial infrastructure including power stations, Tata Steel, the Deeside industrial estate and park and commercial sites at Shotton.