A proven weapon in the battle against pothole repairs

Road maintenance and repair specialists Velocity pioneered an innovative technique to tackle pothole repairs, using it to fix over 750,000 defects per year

Unclassified roads make up around 60% of the UK network, from rural lanes that keep communities connected to the residential streets of our towns and cities.

These are roads that Velocity Roads Group, a maintenance specialist, knows well, having helped local authorities across the country look after them for almost 30 years.

Since the 1990’s, Velocity has pioneered and evolved a new technique to repair potholes and other road surface defects, and prevent them from occurring in the first place – with the development of spray-injection patching.

Now widely used by local authorities and maintenance contractors, repairs are quickly carried out using specialised plant and operators:

  • A defect is blasted with dry, compressed air, removing loose material, dust and debris.
  • Next, a bitumen emulsion is introduced to the air flow. Forced into any cracks and crevices, the bitumen impregnates any voids, forming a seal around the base and sides.
  • Aggregate passes through a venturi and is added to the mix. Each granule is fully coated in emulsion and forced at speed into the defect, compacting from the bottom up.

The aggregate interlock means the repair is immediately ready for traffic, minimising disruption for road users. The binder fully cures, giving a strong, durable patch as the repair blends into the existing road surface.

Suitable for a wide range of road surface defects, the process is used for permanent reactive and preventative repairs, with the machines frequently deployed on a find-and-fix basis, carrying out any adjacent repairs alongside planned interventions to maximise efficiency.

Standards compliant

As an active contributor to the development of industry standards, Velocity operates according to a detailed quality plan.

With the process playing an important role in highway maintenance, the British Standards Institute Committee determined that the process was of sufficient interest to warrant a standard in its own right.

For that reason, BS 10947:2019 Spray injection patching for small-scale pavement repairs – Specification was developed to specify the performance requirements of the installed product and gives the necessary control procedures.

The standard sets out performance criteria for repairs, ensuring a high- quality, robust product is delivered for highways engineers and road users.

For permanent repairs, the performance of the repaired area is under warranty for one year to meet the criteria set out in the standard.

Working in accordance with the standard gives customers confidence, with compliant suppliers conforming to criteria defined in a Type Approval Installation Trial (TAIT).

Proof on the ground

Velocity Roads Group are the largest operator of spray-injection patching machines in the world. The company designs and manufactures the machines in Sunderland, UK. Following the acquisition of fellow spray-injection patching specialists Archway Roadmaster in 2024, the group now operates a fleet of over 50 machines nationwide.

Together, the group now repairs around 750,000 defects per year.

Importantly, Velocity’s in-depth operator training and support, transparent reporting and compliance with standards, fit with the criteria the UK Government imposes to ensure authorities spend money effectively on road maintenance.

“Our customers are well placed to meet the Department for Transport requirements”, explains Velocity’s Managing Director, Dominic Gardner.

“Spray-injection patching is a well-proven technique and an established weapon in the battle against potholes. Because of the speed and efficiency of the process, it represents outstanding value, helping local authorities keep the roads we depend on in good condition. The standards we operate to give them the confidence that they will stay that way.”

Long-term view

Adopting a ‘prevention is better than cure’ approach, use of the technique means that defects can be repaired before they become a bigger problem. Where once a crew would visit a site to carry out a single repair, the efficiency of the process means that a crew can intervene early and repair multiple defects on a road, improving public perception and saving money.

Because there is no excavation involved, no waste is produced, delivering an exceptionally low carbon footprint.

Keeping assets in good condition for longer

Alongside spray-injection patching, Velocity also offers a specialist service for asphalt preservation to protect roads that are in good condition.

Using a proven solvent-based preservative fortified with a naturally occurring bitumen, the treatment penetrates the surface and ‘locks-in’ the condition of assets that are in a good state. It prevents the ingress of water and stops defects from occurring.

Suitable for any asphalt road, preservation stretches the lifecycle of local roads, trunk roads and motorways without the need for costly and carbon- intensive interventions.

An expert partner

Velocity has grown hand in hand with local authorities in the UK and overseas, developing a package together that addresses the challenge of delivering a safe and sustainable road network.

Contributor Details