Three submarine power cables cross Cook Strait between Oteranga Bay in the North Island and Fighting Bay in the South Island as part of the HVDC Inter-Island, which provides an electricity link between Benmore in the South island and Haywards in the North Island.
Fibre optic cables carry telecommunications across Cook Strait, used by New Zealand's main telecommunication companies for domestic and commercial traffic and by Transpower for control of the HVDC link.