Client: Swansea City Council
Contractor: Knights Brown / Gwendraeth Valley Tarmacadam
Location type: Coastal Promenade
Completion: August 2025

The challenge
This £26m coastal protection scheme was developed to help protect residents and businesses in this popular area of Swansea Bay from the risk of flooding and coastal erosion. The existing sea defences, consisting of a 0.5km-long vertical concrete sea wall and a 0.7km sloping revetment, had deteriorated over time and required significant improvement.

Alongside strengthening the sea defences, the project also aimed to enhance the promenade as a key leisure destination. Plans included new decorative surfacing, landscaping, lighting, seating, litter bins and improved links to Mumbles Road.

The works involved raising the promenade by approximately half a metre through the central section, reinforcing the coastal defence structure and revetment, replacing railings with a low pedestrian wall, and widening the promenade to create a shared pedestrian and cycle route.

The project also presented several logistical and environmental challenges. Access for HGV deliveries to this part of the bay was limited, requiring careful coordination of material deliveries to minimise disruption to local residents, businesses and road users.

Construction teams also needed to carefully manage works adjacent to a Site of Special Scientific Interest (SSSI), an important habitat for local and migratory bird species.

Tarmac's solution
Tarmac became involved early in the project as a key supply partner, initially providing aggregate and concrete solutions for the sea wall and associated structures, before supporting the delivery of a decorative asphalt surface that aligned with the client and designer’s vision for the promenade.

Following discussions with the client and contractor, alongside the review of product samples, ULTICOLOUR was selected in a light buff finish for the promenade surfacing.

ULTICOLOUR combines a clear polymer modified binder with pigment and colour-matched aggregates to create brighter, longer-lasting colours with excellent resistance to surface wear.

The client required a durable, low-maintenance solution with a proven track record, and ULTICOLOUR offered over 20 years of performance across the UK, including use on coastal promenades in Blackpool, Morecambe Bay and Whitley Bay.

The surfacing also complemented the surrounding coastal environment while providing the durability required for high-traffic public spaces.

For the sea walls, stairs and slipways, the concrete specification needed to deliver high strength, abrasion resistance and rapid early strength gain to support the contractor’s construction programme.

The design also incorporated detailed patterns and textures cast into the sea wall and low pedestrian wall surfaces. Tarmac supplied a specialist C40/50 micro-silica concrete mix for the sea wall works, with tight slump tolerances required due to the steep gradients involved.

Results and benefits
The project was successfully completed on time and within budget during summer 2025. Tarmac supplied approximately 16,500m³ of concrete throughout the scheme, including around 10,500m³ of specialist high-strength micro-silica concrete.

In addition, 660 tonnes of ULTICOLOUR Light Buff asphalt were supplied and installed by Gwendraeth Valley Tarmacadam.

Despite the complexity of the decorative paving layout and intricate surfacing patterns, the contractor achieved a high-quality finish throughout the promenade.

The successful delivery of the scheme relied on close collaboration between Tarmac’s asphalt and concrete supply networks, the contractor team and wider project partners.

Careful planning and coordination ensured materials were delivered efficiently while minimising disruption throughout the programme.

The completed sea defences are expected to significantly reduce the risk of coastal flooding for 126 properties, including residential homes and more than 50 businesses along the Swansea Bay coastline.

Improvements to the appearance and functionality of the promenade are also expected to further support the local tourism industry, which already contributes around £660m annually to Swansea’s economy.

Having reviewed the long-term performance of ULTICOLOUR on previous coastal projects, the client was also confident in the durability and lifespan of the new surfacing solution.

The final result demonstrates the value of a collaborative approach between all project stakeholders.