In this method, a series of pipes or ducts are first laid in a trench. The cables are then pulled through these ducts from a manhole or pulling pit.

• Benefits: This method offers superior protection for the cables and greatly simplifies future repairs or replacements, as new cables can be pulled through the existing ducts without further excavation. It also provides a clear physical separation from other utilities.

• Drawbacks: The initial installation cost and time are higher due to the need for duct installation, and heat dissipation is not as efficient as with direct burial, potentially requiring a larger duct or specific thermal backfill.