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May 15, 2023

4 mins read


Thinking about a new dock? Beware of submarine cables.

Because safety is so important to us, we always stress the importance of contacting Ontario One Call when doing any project involving digging – even at the shoreline or underwater.

In addition to the land equipment most are familiar with, Hydro One equipment is also located in lakes and rivers. These are called submarine cables.

What's a submarine cable?

  • Submarine cables are submersed high-voltage underwater electrical cables used to bring power to your shoreline located across a body of water.
  • These cables often run in and out of the water up onto the shoreline feeding into green pad-mounted equipment.
  • This equipment's main function is to step down the voltage to bring service to your cottage or residence.

Underground cable locates are required for all projects big and small. This includes installing a new dock, building boathouse foundations or performing dredging in the water.

What happens if you make contact with a submarine cable?

Each year Hydro One responds to significant outages that are a result of contact damage to submarine cables.

If you sever or make contact with any of Hydro One’s submarine cables, you may not only cause a power outage to you and your neighbours, but it may also result in costly repairs or injuries.

Left undisturbed, these cables are safe in the water; however, damage to the cable could have very serious consequences.

When you plan ahead, you avoid potential power loss, damage liability and serious personal injury.

Example of submarine cable
Submarine cable diagram

Contact Ontario One Call before you begin any project big or small.

Before performing any work in and around the shoreline, be sure to contact Ontario One Call and clearly indicate where you plan on working. This service is available 24/7 through their website or by calling 1-800-400-2255.

You will receive information regarding the location of any submarine cables in and around the shoreline that may be present in your proposed work area.

Hydro One reminds customers and the community to keep safe distances away from our equipment and our crews while they’re working.