Telecommunications cables are critical to everyday life, so protecting their physical security is a priority for engineers and designers. It can be a challenge, however, to know just how deep to bury telecommunications cables. While every installation is unique and presents its own set of challenges in determining the proper burying depth, but some considerations can be universal.

Planning the depth

Telecommunications cables are considered low voltage and do not need a specific burying depth like higher voltage cables. Burying depth is still a crucial factor in keeping the cables safe, though.

The first step in planning a cable installation should always be to check both city and county regulations to plan the proper depth and adhere to those regulations.

Most requirements will indicate that telecommunications cables should be buried a minimum of 24-30 inches from the ground’s surface and five feet from the pavement’s edge. If the cables are buried in any of the following scenarios, the minimum burying depth requirements may be affected:

  • Under roads or railroads
  • Under ditches or drainage areas
  • Near road crossings
  • In an area with high seismic activity
  • In a cropland or pasture

Depth can also be influenced by the installation route.

Planning the route

Knowing the installation’s route is paramount to determining burying depth, as the route can introduce new factors to consider.

As engineers or designers plan cable installation routes, they should draw from several sources of information. Some sources include:

  • Visual inspections
  • Record drawings (often available from facility owners or local utilities or municipalities)
  • Scaled drawings from land surveyors

During this fact-finding mission, engineers or designers should look for anything that could impact the installation, such as:

  • Underground obstacles
  • Building foundations
  • Exposed features
  • Changes in elevation
  • Relative distances

All these factors can influence both the route and the burying depth of the cable installation and should be considered for any calculations.

The bottom line

When determining the proper burying depth, engineers and designers should remember their main goals are

  1. Adhere to local regulations
  2. Protect the telecommunications cable from outside elements.

Keeping those guiding principles in mind will help them make the right decisions about burying depth on future projects.

Burying depth isn’t the only factor engineers and designers have to determine when planning telecommunications installations. Check out ways to maximize conduit capacity for more considerations.