Rastrick Bridge Emergency Scour Repairs
Rastrick Bridge – Emergency Scour Repair & Structural Stabilisation
Location: Rastrick, West Yorkshire
Sector: Highways / Structures / Flood & Scour Protection
Services: Scour Repair | Civil Engineering | Commercial Diving | Temporary Works | Environmental Permitting
Emergency Response Following Severe Flooding
Following severe flooding across the UK in early 2020, Rastrick Bridge required urgent intervention after significant scour damage was identified around one of its masonry piers.
The three-span masonry arch bridge carries the A643 over the River Calder. During the flooding, a shipping container was swept downstream and became lodged against the upstream face of the structure. The obstruction altered river flows around the affected pier, contributing to significant localised scour.
Once river levels had subsided and the container was removed, an underwater inspection identified areas of concern around the pier. As a result, the bridge was immediately closed while its condition could be assessed and an appropriate repair developed.
With the closure causing significant traffic disruption and increasing pressure to reopen this important route, Kaymac Marine & Civil Engineering was approached to interpret the existing survey information, develop a practical repair methodology and deliver the works within a challenging programme.
Developing the Solution
Following an initial site assessment, Kaymac’s engineering team developed a bespoke underwater repair solution that allowed the works to be undertaken predominantly through commercial diving operations.
Our methodology incorporated Kaymac’s modular steel pontoon system to provide safe working access within the river, alongside specialist plant and temporary works required to complete the repair.
A key consideration was protecting the River Calder throughout construction. Kaymac worked closely with the Environment Agency to demonstrate that the proposed methodology would minimise the risk of pollution and prevent construction-generated suspended material from being dispersed downstream.
Through early engagement and close liaison, the necessary Flood Risk Activity Permit was secured within approximately one week of the initial application.
At the same time, Kaymac progressed material procurement, temporary works planning and buoyancy calculations for the floating plant. This concurrent approach meant mobilisation could commence as soon as the environmental permit was received, helping minimise the overall duration of the road closure.
Delivering the Underwater Repairs
Kaymac constructed a temporary access ramp to enable its modular pontoon system to be safely installed within the watercourse.
Working from the pontoon, Kaymac’s directly employed dive team excavated loose riverbed material from around the affected pier to the required formation level, assisted by an excavator operating as part of the coordinated works.
Underwater formwork was then installed by Kaymac’s divers in preparation for the structural repair.
An approved underwater concrete mix was placed using a concrete boom pump positioned away from the bridge structure to avoid imposing additional loading. The concrete filled the scour void and stabilised the affected pier.
Rock armour was subsequently installed around the pier cutwater to provide additional long-term protection against future scour.
All temporary and permanent works associated with the underwater repair were undertaken by Kaymac’s directly employed workforce, providing the client with a coordinated solution from methodology development through to delivery.
Quality Assurance Below Water
Underwater construction introduces particular challenges around inspection, verification and quality control.
Drawing on extensive experience delivering submerged structural repairs throughout the UK, Kaymac developed a project-specific Inspection & Test Plan covering each stage of the works.
Hold points, inspections and quality records were incorporated throughout delivery to demonstrate that the repair had been completed in accordance with the approved methodology and specification.
The Outcome
Through early engineering input, environmental liaison, temporary works planning and specialist self-delivery, Kaymac was able to turn existing survey findings into a practical construction solution and rapidly mobilise the required resources.
The completed works stabilised the scour-affected pier, provided additional protection against future erosion and enabled the asset owner to progress towards reopening this strategically important highway structure.
Key Capabilities Demonstrated
- Emergency response following flood and scour damage
- Interpretation of underwater inspection and survey information
- Development of bespoke construction methodologies
- Temporary works and floating access systems
- Flood Risk Activity Permitting and Environment Agency liaison
- Commercial diving and underwater construction
- Excavation and riverbed preparation
- Underwater formwork and concrete placement
- Rock armour scour protection
- Directly employed specialist workforce
- Inspection, testing and quality assurance
- Delivery under significant programme and stakeholder pressure
