What it involves

Any combination of techniques and products used to rehabilitate a pipe or establish a new pipe using trenchless techniques. Often a problem is considered and trenchless solutions will be ruled out because no one technique will deliver all elements of the project; in these scenarios however McAllister Bros. would advocate using a combination of systems such as making use of spot excavation or ‘key hole’ repairs to allow customers to attain the benefits of utilising No-Dig techniques.

Our Service 

  • Concept design is a key element, establishing what is known/unknown and the potential of integrating solutions
  • If the concept combined solution offers you benefits and value for money, we would move towards constructing a detailed design working with an appropriate consulting engineer and where appropriate product manufacturers
  • The installation methodology is then established, if appropriate trialled and then installed
  • Often the installation is relatively straightforward once the right methodology is established and the ‘right’ people work as an integrated team to ensure no ‘boundary’ handover problems occur

Our Process

  • A simple example would be the use of guided auger boring followed by CIPP lining. When boring from a shaft to a tunnel, it may not be possible to remove the casings and jack in a PE pipe. One solution could be to use UV cured CIPP lining to provide the structural pipe with an appropriate design life
  • A frequently occurring problem is how to deal with collapses in runs where excavation is prohibitively expensive. The McAllister Group frequently uses combinations of solutions by adding strategic new chambers then pipe reaming through partially collapsed sections and CIPP lining ‘newly created sections’ that have no significant deformation but require long-term structural rehabilitation


  • Pipes where there is an overwhelming need to minimise excavation and trenched solutions
  • The flexible nature of deriving the most relevant and effective solution means there are no hard and fast requirements

When to use combination solutions

When single / traditional solutions have been discounted and the benefits of no-dig solutions for any or all of the solution are significant

Why choose the McAllister Group for Combination Solutions

Experience – Since starting working on waste water infrastructure in 1974, the McAllister Group has routinely considered, created and delivered solutions using integrated processes and products. Our collaborative approach and strong relationships with manufacturers, designers and supply partners has evolved to empower us to quickly build integrated teams to generate and deliver combined solutions

Approach – Draw on experience, think laterally within the bounds of the infrastructure issue, collaborate and share information, focus on securing the right solution for the client. Advances in technology and a burgeoning experience curve allow us to create more advanced and effective solutions for our clients utilising a combination of individual trenchless solutions.