Nant y Wedal river restoration

Overview

Click to read this page in Welsh / Cliciwch i ddarllen y dudalen hon yn Gymraeg

Natural Resources Wales (NRW) is continuing work to improve the natural character of Nant y Wedal in Heath Park, Cardiff.

Nant y Wedal ('nant' is the Welsh word for stream) is a tributary of the Roath Brook. The stream is culverted (hidden underground) for much of its length but flows openly in Heath Park. It is this stretch through Heath Park which is the focus of this project.

Building on feedback received during our consultation at the end of 2024, we are now progressing the next design stage of the restoration project.

Why we want to restore Nant y Wedal

Nant y Wedal is currently in a heavily modified and degraded ecological condition, with the upper stream deeply incised and largely disconnected from its floodplain. The channel was historically straightened resulting in the lack of natural features such as river bends and depositional areas. In the downstream woodland section, bare and shaded banks are contributing fine sediment to the stream, while footbridge damage and bank poaching affect channel stability. Several ageing structures, including footbridges, a timber flume, and a pipe culvert interrupt the natural movement of water and sediment.

What we want to achieve

Through this project, NRW aims to:

• Restore more natural river processes and improve overall habitat condition
• Reduce erosion and siltation, helping to protect local infrastructure
• Create better habitats for fish, insects, and other wildlife
• Increase resilience to climate change and extreme weather
• Enhance the river corridor as a valued green space for the community

The designs we are developing focus on practical, sustainable measures that balance environmental needs with the way people use the surrounding area.

What are the restoration options

The restoration proposals for Nant y Wedal include:

• Channel re-meandering
• Channel shape restoration/ Reprofiling banks
• Footbridge replacement and upgrade
• Riparian zone planting
• Natural woodland creation
• Woodland management
• Addition of in-channel woody material
• Remove timber flume and reprofile banks
• Remove twin culvert and upgrade footbridge

Who we are working with

Natural Resources Wales and Cardiff Council are working in partnership to progress the project. Other project stakeholders include the University Hospital of Wales, Dŵr Cymru Welsh Water and local community groups such as the Friends of Heath Park, The design work is being completed by JBA Consulting, supported by a team of consultees as required.

How we used your feedback

In December 2024, we carried out an online consultation and a public drop-in event to gather views on the initial concepts for the Nant y Wedal restoration. We received valuable feedback from residents and local groups.

We have carefully considered all comments as we developed the new updated design.

Read the Nant y Wedal Outline Design Report, which includes a summary of the survey responses.

Design overview

Concept designs

Pedestrian footbridges – Concept design examples

Here are four example footbridges that could be used as part of the restoration works.

Source: CTS Bridges | Details, information & images of Steel & Timber Bridges

Consultation

We are now ready to share the updated design and gather further views before moving into the final design stage.

You are invited to join us at a public drop‑in event:

Date: Tuesday 17 March
Time: 3pm – 7pm
Location: Heath Park Miniature Railway (Lecture Room), King George V Drive East, Cardiff, CF14 4AW.

Members of the project team will be available to talk through the design in more detail, answer questions, and listen to any further feedback.

Project timeline

2023/24: Initial design development.

December 2024: Public consultation and online survey on early concepts for the restoration work. Feedback gathered from residents, community groups and stakeholders.

2025 – Early 2026: Development of the updated design, incorporating public feedback.

March 2026: Further public consultation on the updated design.

Spring–Summer 2026: Refinement for the final design, submission of any required permissions and consents and preparation for construction.

2027: Subject to approvals and continued funding, construction and restoration work planned to begin. Ongoing communication with residents before and during works.

Reporting pollution

Although improving water quality is not the primary focus of the project, we know it is an important concern for local people and for NRW. Your reports help us identify issues quickly and take appropriate action.

If you see anything that looks like pollution in or around the watercourse, please report it 24/7:

• Online: naturalresources.wales/reportit
• Incident hotline: 03000 65 3000

Signs of pollution to look out for may include:

• Unusual discolouration of the water
• Sudden or strong odours
• Dead or distressed fish or wildlife
• Excessive foam, oil-like sheens, or thick scum on the water surface
• Sewage debris or suspected spills
• Sudden drops in water levels or cloudy/milky discharges

If it’s safe to do so, please provide details such as the location, what you observed, and when it happened. This helps us respond more effectively.