The short answer, based on general industry standards and the National Electrical Code (NEC), is that fiber optic cable is typically buried between 24 inches (60 cm) and 30 inches (76 cm) deep. However, simply hitting this depth isn't enough to guarantee your network survives. Factors like the. Our underground cables are protected by renewable or permanent agreements with landowners or have been laid in the public highway under our licence. 8 million km in scope by 2025 (per TeleGeography), burying these cords of light comes with the benefits of avoiding cable damage, decreasing downtime, and extending their operational lifetime. Use this page to plan trench depth, compare conduit options, and prepare for inspection conversations.