A practical, engineering-focused guide to planning and installing underground fiber optic cables with the right cable structure, trench design and protection level for long-life, low-risk networks. 2 meters (3-4 feet) deep to reduce the likelihood of accidentally being dug up. It forms a critical backbone for modern communication networks across both urban and rural environments. FO-VC2 JOINT USE - VERICAL MIDSPAN CLEARANCES 48. APPENDIX A - COVER SHEET / TOC 52. This document discusses techniques for trenching and laying optical fiber ducts. Microtrenching has been. Underground placement is necessary and unavoidable in certain areas for various reasons such as nature and heritage conservation, natural obstacles, aesthetics, space and safety. Placing cables underground has the added benefits of reducing transmission losses, aiding planning consent and reduced.