The National Cycle Network is a much‑loved lifeline - linking communities, supporting active travel, and offering peaceful green spaces for people and wildlife. Yet the recent landslide on the Swiss Valley path (Route 47) shows how increasingly extreme weather is putting these treasured routes under real pressure.
Infrastructure, like the one on the Swiss Valley, which was built for a very different climate, is struggling under modern weather extremes. Credit: Rafael Bastos.
Extreme weather is putting cherished cycle routes like Swiss Valley at risk.
It shows how the unseen work by our maintenance teams is vital to keeping people safe and routes open.
In this blog, we're sharing how climate change is driving more events like it, and how Matthew and colleagues across the Network are working tirelessly to protect the places you love.
Climate change and the National Cycle Network: A rising challenge across the UK
Intense weather, such as storms and heavy rainfall are becoming more frequent and more severe, fuelled by a warming atmosphere that can hold and release more moisture.
According to the Met Office, six of the UK’s ten wettest years on record have occurred since 1998, and heavy rainfall events are increasing in both intensity and frequency.
There is an urgent need for climate-resilient infrastructure across the nation to combat this.
Climate change is amplifying storms, with human-induced warming increasing rainfall during major weather events by around 20%.
Wales, in particular, is already experiencing disruptive weather extremes, according to the National Infrastructure Commission for Wales.
These changes pose significant challenges for the National Cycle Network, much of which relies on historic railway embankments, Victorian bridges, culverts and waterways, none of which were designed to withstand today’s extremes.
What Happened at Swiss Valley?
On 4 November 2025, the Swiss Valley path in Carmarthenshire experienced a major embankment failure following extremely intense rainfall, which caused flooding across the region.
Flooding overwhelmed a Victorian-era culvert that carries a small stream beneath the embankment.
Once the culvert reached capacity, water backed up behind the embankment until it burst, leading to a landslide that destabilised and destroyed a significant section of the path.
To protect public safety, the route was immediately closed between the B4306 and U2263 bridges.
While this event was local, it reflects a nationwide trend.
The infrastructure, which was built for a very different climate, is struggling under modern weather extremes.
The recent landslide on the Swiss Valley path (Route 47) shows how increasingly extreme weather is putting treasured routes under real pressure. Credit: Rafael Bastos.
What we’re doing now at Swiss Valley
Repairing a failure of this scale is complex, costly, and technically demanding, especially on a 200 year old foundation.
Our engineering and ecology teams have already taken several major steps:
1. Full topographical survey complete
We now have precise measurements of the landslip area and a mapping of the embankment’s failure zone.
2. Geotechnical specialists
We are working with an expert consultant who is producing an outline engineering design to reinstate the embankment safely and sustainably, ensuring it will last for future generations.
3. Ecology
We’re identifying any species, habitats, or seasonal constraints that must be protected during construction, to make sure we are looking after the world around us as best we can.
4. Making the most of your support
We’ll compare reinstatement designs and costings so we can make sure we apply the most cost effective, long‑term solution; making your donations go further, and last for years.
Due to the high cost of reinstatement, we will do our best to also seek financial support from partners and funders.
One thing we can’t do yet is confirm a reopening date.
With such a significant structural failure, timelines depend on funding, ecological constraints, and engineering requirements.
Matthew is an Estate Supervisor at Walk Wheel Cycle Trust, working on many routes in the area, including Route 47.
A day in the life of an estate worker: Matthew’s story
Although spectacular infrastructure failures make headlines, most of the key work that protects the Network happens every day, quietly, by the hands of our maintenance teams.
Estate worker, Matthew, describes his team’s role as 'keeping the paths accessible, safe, and alive with nature.' That includes:
Keeping the network safe and open
- Cutting grass and managing vegetation so routes don’t become overgrown or hazardous.
- Repairing path surfaces built 25–40 years ago on former railways.
- Monitoring and maintaining centuries‑old Victorian structures, bridges, culverts, embankments, many of which are becoming harder and more expensive to repair due to age.
Protecting and growing biodiversity
- Planting trees and hedgerows.
- Creating ponds and seeding wildflowers.
- Installing bird, bat, and bug habitats.
Matthew explains that many routes were originally built on tight budgets by volunteers.
Today, his team faces the challenge of maintaining this legacy infrastructure under weather that is far more extreme than what it was designed to endure.
Much of the National Cycle Network relies on historic railway embankments, Victorian bridges, culverts and waterways, none of which were designed to withstand today’s weather extremes.
Why our work matters more than ever
Climate change means:
- More frequent and intense rainfall.
- More storm damage to paths, culverts, bridges, and embankments.
- More long-term closures if repairs can’t be funded quickly.
The success of the National Cycle Network is the story of countless people whose time, passion and collaboration went from building and maintaining 318 miles in 1995 to now over 12,500 miles across the UK.
But currently, there are areas which are at risk if we don’t act soon; they may face closure.
Protect the National Cycle Network
Extreme weather is threatening community lifelines across the UK. Will you help protect the most vulnerable routes before it's too late?
Without ongoing support, more sections may face the same fate as Swiss Valley.
We rely on your kind donations and generous funding from partners to repair routes after weather events, and future‑proof the Network, to make it more resilient for generations to come.
As climate change accelerates, your support becomes essential to keeping paths open and safe for everyone.
