Frequently asked questions

Why was Barmouth at risk from flooding in the past? 

Historic flooding in Barmouth has been caused by its geographical predicament. The town is nestled between the Rhinogydd hills and the Irish Sea, meaning when severe storms do occur, Barmouth is in the direction of the prevailing wind. When wave overtopping occurs, there is not much land space for the flood water to spread out, and thus flooding issues are concentrated along the thin strip of flat land which Barmouth is situated on.

Is Barmouth at risk from flooding today? 

Yes unfortunately. Overtopping occurs at the northern end of the promenade in ‘benign’ conditions i.e. median level tides, without tidal surge, swell, low pressure or high winds. The most notable recent storm event (January 2014) forced the emergency
evacuation of the Promenade café.

Overtopping from this frontage caused extensive damage to the Cambrian coastal railway. The northern area of the promenade is also at risk from the tide-locking of two watercourses. This means that when the sea rises during a storm, the water draining off the land from the two streams has nowhere to go. Flap valves on the exit-points of the two watercourses have also failed, risking sea water ingress.

In the absence of investment, 757 properties are predicted to have more than a 1 in 100 chance of flooding in any year. The rapid onset and depth of flooding presents a risk to life. Sea level rise due to climate change is predicted
to accelerate, increasing the likelihood and severity of coastal flooding. By 2069 mean sea levels are predicted to have increased by 0.42m and by 2119 by 1.1m.

What else are YGC and      ARUP doing for the community? 

In line with the various overlapping aims and objectives of the organisations and people involved in the project, the work will investigate both recreational and environmental enhancement of the shoreline area.

Will there be much disruption? 

As with all large construction projects, there is bound to be some disruption through traffic management, noise pollution, impacted view and lack of access to certain areas. However, all of these are temporary, and will be minimised to the best of our ability. It is difficult to say at this stage what the disruption is likely to be like as a final decision on the proposed works has not been reached yet.

How can I have my say as a local resident? 

Gwynedd Council and YGC are keen to hear from the residents of Barmouth and the surrounding area so we can understand what you’d like to see out of this project, or if you have any queries about our work. Visit our contact page to get in touch.

I’m interested in the specifics of the project… Where can I find this information? 

The technical information supporting this project can be found on the ‘Technical Documents’ page on this site. If you can’t find what you’re looking for, then please get in touch, or file a freedom of information request with Gwynedd Council.

What does a 1 in 100-year event mean?

The commonly used phrases of “1 in 100-year, 1 in 50-year flood” and so forth refers to the estimated probability of a storm event happening in any given year. A 1 in 100-year flood has a 1% chance (or 1-in-a-100 chance) of occurring in any given year.

The term “1 in 100-year flood” allows us to place a particular weather event in context with other similar events. It is wrong to think that a 100-year storm happens only once every 100 years.

While not likely, two 100-year storms can occur within a week of each other. In other words, over the course of 1 million years, these events would be expected to occur 10,000 times.

But, just because it rained 200 milimetres in one day last year doesn’t mean it can’t rain 200 milimetres in one day again this year. 

Barmouth flood alleviation scheme

YGC | Ymgynghoriaeth Gwynedd Consultancy


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