The original Traffic Separation Scheme (TSS) for the Strait of Hormuz was jointly proposed by Iran and Oman and adopted by the International Maritime Organization (IMO) in 1968. It established separate inbound and outbound shipping lanes, each approximately two nautical miles wide, separated by a two-nautical-mile buffer zone, creating a predictable and internationally recognised transit corridor through one of the world's most critical maritime chokepoints. Originally, significant portions of these established shipping lanes passed through Omani territorial waters, providing the deepest, safest and most practical route for commercial traffic. Under the traditional arrangement, westbound traffic utilised the northern lane while eastbound traffic utilised the southern lane, with the separation zone reducing the risk of collision in a waterway barely 30 miles wide at its narrowest point. The situation now represents a dramatic departure from that long-established system. During the 2026 conflict, Iran laid naval mines within or adjacent to sections of the recognised shipping corridor. Western maritime authorities, insurers and shipping companies have repeatedly warned that substantial mine threats exist along the traditional route, with some reports suggesting as many as 80 mines remain to be cleared. Clearing the minds could take two months (intensive operations) - however, its not the clearing of existing mines which is the issue - Queshm remains the issue: It sits directly astride the northern side of the Strait of Hormuz and is only a short transit from the shipping lanes. A small IRGC fast craft carrying a handful of moored mines can leave a sheltered harbour, lay mines at night, and return within hours. This is precisely this asymmetry that Iran relies upon, the cost of laying them is tiny compared with the cost of finding and removing them - its why Qeshm is so strategic and ultimately why Iran can hold Gulf Shipping hostage whenever it wants until Qeshm is obliterated. Its also worth noting that Iranian naval mining is not a new. Iran first employed mines extensively during the so-called Tanker War phase of the Iran-Iraq conflict in the 1980s, culminating in the mining of international waters in 1987-88 and the strike on USS Samuel B. Roberts in April 1988. The tactic has therefore formed part of Iran's maritime playbook for nearly four decades. Below is the original 1968 Traffic Separation Scheme. Below that is the contemporary hazard picture. The mining of the traditional transit corridor has forced vessels away from established routes and towards channels closer to Iranian-controlled waters, placing Tehran in a position to exert greater influence over maritime traffic through a waterway it is now seeking to regulate, administer and potentially monetise through permits, fees and transit controls.
