Precast Concrete Box Culverts

What is a box culvert?

A box culvert is a monolithic, flat-sided precast concrete structure with walls at 90 degrees to the floor and roof.  Box culverts were introduced to provide an easily-installed conduit for culverting of watercourses where construction can create an obstruction to the natural flow path.

Box culverts can also be used for attenuation of surface water as part of a sustainable drainage system (SuDS), horizontal tunnels and subways, sewers and access shafts. Smaller box culverts can also be used for dry networks including cabling.

Box culverts are available in many different size and shape configurations. Square or rectangular units can be used as single or multi-unit runs, giving excellent structural and hydraulic performance. Extensive design possibilities can be achieved with the use of end walls, access points, vent holes, inlets, outlets, double rungs, splayed ends, starter bars and threaded sockets, a range of different inverts, low-flow channels and dished inverts.

 Box Culvert Applications

  • Watercourse diversion
  • Attenuation and storage of surface water
  • Open channels and sewers
  • Pedestrian and vehicle subways
  • Access shafts
  • Service tunnels and ducts

 Why use precast concrete box culverts?

  • Concrete box culverts are resilient against damage from high pressure water jetting, a commonly used process for cleaning and blockage removal in sewers.
  • Precast concrete box culverts are a low carbon, sustainable product made from local materials that can be recycled end of life.
  • Precast concrete box culverts can be designed to withstand full highway vehicular loadings and can be constructed in shallow or deep fill installations.
  • Precast concrete box culverts require minimal maintenance and are able to retain their shape over their long service life, preserving structural integrity and hydraulic efficiency.
  • Precast concrete box culverts can be manufactured in a wide range of sizes and can accommodate many different features.
  • The self-weight of box culverts provides natural resistance to flotation in high groundwater and during flooding.
  • Precast concrete is strong and durable, providing asset owners with low whole life costs and a proven service life of more than 100 years.