How are Fiber Optic Lines Installed Underground?

When constructing our fiber optic network, we use a combination of aerial and underground construction. While many customers understand how aerial construction works, we often get several questions about how we install underground. Here we’ll address some of those questions.

What to Expect During Installation

When installing fiber optic to your home, we generally follow existing utilities in the area, either aerial or underground. If it is determined that a new fiber optic cable needs to be installed underground, a technician will contact you to ask some questions about your property.

Some of these questions include:

  • Do you have a sprinkler system?
  • Is there an invisible dog fence?
  • Do you have private electric lines past the meter?
  • Do you have a septic system, tile drains, or sump pump drains?
  • Do you have any private utility lies like gas or water?

If the answer to any of these questions is yes, the technician must be notified, or the customer will need to mark the location of the private lines so that Mainstream Fiber Networks does not damage these during construction.  We use Dig Safe (811) to do locates in the area, but this service only covers public utilities.

After any the private lines are located, a request will be placed with the local Dig Safe (811) company to mark your public utilities. The utility companies’ locators will use flags, spray paint, or chalk that will eventually wash away. This step MUST be completed prior to the start of digging, as it helps ensure that we do not damage any utility lines.

Once utilities are marked, we assign our Underground Fiber Optic Cable Crew to install the fiber optic cable. If you have requested to be home for the work, or if you have pets or locked gates, we will contact you to schedule a time for your work to be completed.

Possible Delays

If there are no delays, it can take up to 14 days from the date the technician places the order for your new underground fiber optic cable to be installed. Unfortunately, we do encounter occasional delays such as:

  • Permits – In some communities, we are required to apply for and receive a permit before we can place the fiber optic cable. Permit approvals can take anywhere between 5 – 30 days.
  • Weather Conditions – Snow and rain can impact both the equipment used to bury the fiber optic cable and the ground conditions in such a way that we are unable to dig. Since the weather is often unpredictable, the amount of time these delays can last is as well. Typically, weather delays can last between 1-7 days. Extreme conditions such as the ground freezing or flooding can result in longer delays.
  • Underground Utility Locates – All utilities must either mark their lines, or let us know they have no lines where we are digging. If a utility is unresponsive, or if the response is unclear, a new request must be submitted. Normally this causes a 3-day delay but could be longer or shorter depending on the situation.
  • Other Issues – Other delays can be caused by events such as parades or festivals that may limit our access, or we may need other equipment to perform the work at your home. In the event of a delay other than the ones listed above, our Underground Fiber Optic Crew will explain the issue, as well as provide an estimated time for completing the work.

We hope this information helps answer questions about the steps involved in building an underground fiber optic line, but If you have any questions about this process, please give us a call at (844) 752 – 6736 or email us at