What are Multi Utility Tunnels (MUTs) or UTILIDORS or Utility Corridors?

A utility tunnel is “any system of underground structure containing one or more utility service which permits the placement, renewal, maintenance, repair or revision of the service without the necessity of making excavation; this implies that the structure is traversable by people and, in some cases, traversable by some sort of vehicle as well” (APWA 1997).
Internationally there are many names given to MUTs, such as;
  • CSTs or Common Service Tunnels (Singapore),
  • CUTs or Common Utility Tunnels (Malaysia),
  • CUEs or Common Utility Enclosures (Hong Kong),
  • Les Galeries Multiréseaux (France).
Underground utilities include storm sewer, electric, sanitary sewer, gas, water, telephone and cable. Utility conflicts are typically avoided during the design process. However, in some cases, existing utilities are not properly identified or located during the design process. In other instances, the location of the utility is known, but adequate construction controls are not in place. Both can result in a negative impact to an existing utility when installing a new utility. A utility tunnel is considered an optimal solution to avoid underground crowding of utilities in narrow lanes. Shared infrastructure can save significant costs, especially when provision is made for maintenance, upgrade and growth over the lifecycle. It mainly requires cooperation among stakeholders.

The Necessity of Utilidors

At the start of the 21 st century, ‘quality of life’ is considered to be strongly dependent on an invisible utility infrastructure (i.e. electricity, gas, communications, water and wastewater) and a visible transport infrastructure (i.e. that which facilitates worker migration and passage of goods). When roads are resurfaced they are inevitably dug up too soon by utility companies and when utilities are maintained they consequently interrupt traffic flow; in short the maintenance provision for each clearly conflicts. Traditional methods are becoming un-economical, socially disruptive and environmentally damaging, or in broad terms unsustainable. A sustainable approach is much required to utility installation through the use of multi-utility tunnels (MUTs), which are “smart” (facilitating utility installation, maintenance, renewal, condition monitoring, asset location and leak detection) and open-ended (allowing for additions).
The following attributes can serve as an example which emphasizes on the development of Utility Corridor Systems.
  • Advancements in Communication
  • Material of Supply Pipelines
  • District Heating & Cooling Systems
  • Storm water Management
  • Cargo Tubes
  • Potable and Reclaimed Water
  • Limited space at surface (Utilization of subsurface is important)
  • Easy Access to installations
  • Isolation and protection from natural disasters
  • Environment protection


  • Provides easy access and known location for all utilities
  • Provides space for future utility additions without significant additional cost
  • All lines under one channel, therefore (Requires less space , Reduce overall cost of multiple installations)
  • Highly beneficial in urban areas where surroundings need not to be disturbed
  • Minimum surface trenching leads to minimal impact on roads and thus reduces asphalt overlay costs
  • Simplified and continuous access to utility
  • Better preparedness and quick pin pointing of problem during disasters and emergencies
  • Minimizes environmental impacts like noise, vibration, dust, disruption to traffic and services
  • More efficient use of underground space than separately buried utilities
  • Optimal solution to avoid underground crowding of utilities
  • Reduced damages or influences to above ground facilities
  • Long life, Sustainable and Cost Effective


Source: Sustainable Utility Infrastructure via Multi-Utility Tunnels (D.V.L Hunt and Chris David Foss Rogers – May 2006)