Bury cables from 12-36 inches (or 30-90 cm) deep. Where plant life, sidewalks, and other utilities already disrupt earth, it's safer to bury at as little as 24 inches or 60 cm, using protective conduits to limit the likelihood of damaged cables by inexperienced maintenance or. Bury cables from 12-36 inches (or 30-90 cm) deep. By understanding these principles, network operators, engineers, and contractors can make. Fiber optic cables transmit data as light pulses through a core, offering bandwidths up to 400 Gbps via wavelength-division multiplexing (WDM). 2 meters (3-4 feet) deep to reduce the likelihood of accidentally being dug up. Shallower depths are permissible when individual lengths are placed within conduits. However, it has been known that some cables might.