Trenchless installation refers to a group of advanced techniques that allow for the installation of underground utilities without a traditional open trench. The most common method is Horizontal Directional Drilling (HDD), which uses a steerable drill head to bore a pilot hole along a predetermined path.

• When to use: Trenchless methods are ideal for crossing rivers, roads, railways, and environmentally sensitive areas. They are also essential in densely populated urban environments where open excavation would cause significant disruption to traffic and businesses.

• Benefits: Minimizes surface disruption, reduces environmental impact, and is often the only feasible option for complex crossings.

• Drawbacks: It is a more specialized and expensive process, and it requires careful geotechnical surveys to avoid existing underground obstacles.