PREPARING FOR THE WORST
NRW maps out areas at most risk as millions are spent on flood defences
FLOODING, as some communities are painfully aware, is often just a storm away.
A kink in polar or sub-tropical air can bring the jet stream over Wales and all of a sudden all hell lets loose.
Earlier this month, the country saw a month of rain in 24 hours, mostly in the south.
Wales’ mountainous topography means it is often river catchments that bear the brunt.
But with the right tidal and atmospheric conditions, the Irish Sea can surge and send water up estuaries and over flood defences.
Climate change may increase their regularity and amplify the magnitude of their effects. Seas may rise slower or faster than forecast, and when they do, coastal settlements will become more vulnerable and estuaries will back more run-off water into river catchments.
The Welsh Government and Natural Resources Wales (NRW) has published interactive maps showing predicted levels of risk of flooding across Wales. Some areas are currently being updated, including parts of Bangor and the Welsh Marches.
During the previous Senedd term, the Welsh Government spent £390million on flood and coastal erosion risk management, cutting flood risks for more than 47,000 properties. A similar number of homes and businesses are being targeted for protection this Senedd term.
Coastal schemes under construction include Colwyn Bay, Penrhyn Bay and Aberdyfi, while planned projects in Rhyl and Prestatyn were awarded a total of £92m for coastal defences in December.
Speaking in the Senedd, Climate Change Minister Julie James said: “We don’t just invest in large schemes. This year, our small-scale works grant received 90 different applications, totalling £3.8m. We estimate 3,100 properties will benefit from this funding.
“We are investing more than £3 million through our natural flood management programme, as we look to utilise natural processes to store, slow and infiltrate flood waters to reduce flood risk. We estimate this will benefit around 800 properties.”
Each year, NRW spends around £17m on flood defence projects, prioritising communities most at risk. Given the threats that lie ahead, there will never be enough money to safeguard everyone.
Currently, the environmental regulator has around 90 flood-related schemes ongoing in Wales, a third of which are in the six counties of North Wales. This excludes the ongoing development of management plans in places like Fairbourne, Gwynedd.
Many are relatively minor, others involve large-scale schemes.
In Porthmadog this week, NRW hosted consultation meetings to assess public sentiment and gain feedback on the threats facing the coastal town.
Analysis shows that up to 345 homes and 105 commercial properties in the town are currently at risk from a onein-100-year flood.
But our maps indicate that rivers, not seas, will probably pose a bigger risk for most built-up areas in the near to medium term.
For more extreme events (0.1%-1% probability), many coastal communities will be breached, some seriously.
The risk may be low, but that’s not to say it can’t happen in the near future – and as the climate warms, probabilities will rise.
Wales has many reservoirs, but NRW has not calculated the risk they pose in different scenarios.
It said: “We show (the worst-case scenario for the area that could be flooded if a large reservoir were to fail and release the water it holds.”
It goes without saying, the worstcase impacts would be dire.