Background

Scottish Water undertook a major infrastructure upgrade to install a new water main, improving services for more than 200,000 people across the region.

The scheme, delivered by alliance partner Caledonia Water Alliance (CWA), required the installation of drainage infrastructure beneath the Kilmarnock to Dumfries railway line. Given the sensitivity and operational importance of the route, the works needed to be completed without any disruption to rail services.

The challenge

The project presented a unique combination of technical and environmental challenges:

  • Installing a new drainage pipeline beneath a live railway line
  • Avoiding any disruption to rail operations
  • Accommodating non standard access requirements, necessitating bespoke components
  • Working within a highly sensitive archaeological area

During the installation works, previously undiscovered sections of a 2,000 year old Roman wall, part of the historic settlement of Trimontium (80–211 AD), were uncovered. The presence of this nationally significant archaeology introduced additional constraints governed by Scottish Planning Policy and Historic Environment Scotland.

The solution

Marshalls supported CWA by supplying precast concrete drainage products, including bespoke cover slabs manufactured to meet the project’s non standard access hole requirements. These were produced to specification and supplied via Keyline Builders Merchants in Glasgow.

To protect the archaeological remains and prevent damage during construction, CWA implemented a carefully planned access strategy. This included the construction of a 5 metre wide, 1.6km long stone haul road, enabling construction plant and machinery to access the site without disturbing the underlying Roman wall.

The drainage installation beneath the railway line was completed ahead of schedule, with rail services remaining fully operational throughout the works

The outcome

The project delivered a successful drainage and water main installation under challenging constraints.

  • No disruption to live railway operations
  • Bespoke precast cover slabs met site specific access requirements
  • Nationally significant archaeology preserved in line with planning and heritage regulations
  • Infrastructure upgrade completed ahead of programme

The scheme demonstrates the value of combining bespoke precast manufacture, sensitive construction planning and close collaboration between client, contractor and supplier on complex infrastructure projects.