Traffic separation schemes, deep-water routes, and areas to be avoided do not appear on a nautical chart by accident. Every one of these routeing measures is adopted by the IMO and published in a single reference: Ships' Routeing.
The 2025 Edition is the current version, incorporating all routeing measures adopted before September 2025. For navigating officers, passage planners, and fleet managers, the publication is the definitive guide to the IMO-adopted measures that organize vessel traffic in the world's busiest and most hazardous waterways.
What Is Ships' Routeing?
Ships' Routeing is an IMO publication that presents individual descriptions of every routeing measure adopted by the Organization. The publication provides the detailed specifications that hydrographic offices use to chart these measures and that navigating officers use to comply with them.
COLREGs Rule 10 prescribes the conduct of vessels navigating through traffic separation schemes adopted by IMO, and UNCLOS designates IMO as the competent international organization for matters of navigational safety. Ships' Routeing is where those adopted measures are officially documented.
The publication is organized into eight parts:
- Part A: general provisions on ships' routeing.
- Part B: traffic separation schemes and inshore traffic zones.
- Part C: deep-water routes.
- Part D: areas to be avoided.
- Part E: other routeing measures, including recommended tracks, two-way routes, and recommended directions of traffic flow.
- Part F: associated rules and recommendations on navigation for specific traffic areas and straits.
- Part G: mandatory ship reporting systems, mandatory routeing systems, and mandatory no-anchoring areas.
- Part H: archipelagic sea lanes.
What's in the 2025 Edition?
The 2025 Edition incorporates all routeing measures adopted before September 2025. At 874 pages, the publication reflects the cumulative body of IMO-adopted measures across every ocean and major waterway.
Key content areas in the 2025 Edition include updated traffic separation schemes in congested waterways, revised deep-water routes for draught-restricted vessels, new or amended areas to be avoided for environmental or navigational safety reasons, current mandatory ship reporting systems, and archipelagic sea lane designations.
Each routeing measure is described individually with its geographic coordinates, boundaries, traffic flow directions, and any special rules that apply. The descriptions are the source material that hydrographic offices use when charting the measures on nautical charts and electronic chart data.
Why Ships' Routeing Matters
Routeing measures exist to reduce collision risk in congested areas, protect environmentally sensitive zones, manage vessel traffic in areas where navigation is restricted by depth or obstruction, and organize traffic flow through international straits. Without these measures, vessels transiting chokepoints like the Strait of Malacca, the English Channel, or the approaches to major ports would have no agreed framework for traffic separation.
For the navigating officer, Ships' Routeing provides the authoritative description of each scheme. While the general shape of a TSS appears on the chart, the publication contains the precise coordinates, the associated rules, and any seasonal or conditional restrictions that apply. During passage planning, consulting Ships' Routeing ensures the planned route complies with the adopted measure and that the bridge team is aware of any special navigation rules for the area.
Who Needs Ships' Routeing?
The publication is a carriage recommendation for vessels on international voyages. Vessels transiting traffic separation schemes, mandatory reporting areas, or deep-water routes benefit from having the full text available aboard rather than relying solely on chart depictions.
Passage planners, fleet managers, and maritime training institutions also use the publication as a reference for voyage planning, risk assessment, and navigation instruction. The combination of Ships' Routeing with corrected nautical charts and current ADMIRALTY sailing directions gives the bridge team the complete picture of any routeing measure along the intended voyage.
Navigate the World's Busiest Waterways With the Right Reference
Ships' Routeing is the single publication where every IMO-adopted traffic measure is officially documented. The 2025 Edition is current, comprehensive, and essential for any vessel operating in managed waterways. ANS carries the Ships' Routeing, 2025 Edition alongside the full range of IMO publications, charts, and bridge resources. Contact American Nautical Services at +1 (954) 522-3321 or sales@amnautical.com.
Frequently Asked Questions
Q. What is Ships' Routeing?
Ships' Routeing is an IMO publication that presents individual descriptions of every routeing measure adopted by the Organization, including traffic separation schemes, deep-water routes, areas to be avoided, mandatory ship reporting systems, and archipelagic sea lanes.
Q. What is new in the 2025 Edition?
The 2025 Edition incorporates all routeing measures adopted before September 2025, including updated traffic separation schemes, revised deep-water routes, amended areas to be avoided, and current mandatory ship reporting systems.
Q. What is a traffic separation scheme?
A traffic separation scheme (TSS) is a routeing measure that separates opposing flows of traffic using separation zones or lines, traffic lanes, and established directions of traffic flow. COLREGs Rule 10 governs the conduct of vessels navigating through a TSS.
Q. Is Ships' Routeing required aboard vessels?
Ships' Routeing is a recommended carriage publication for vessels on international voyages, particularly those transiting traffic separation schemes, mandatory reporting areas, or deep-water routes. Flag states and company policies may make it a requirement.
Q. How does Ships' Routeing relate to nautical charts?
Hydrographic offices use the descriptions in Ships' Routeing as the source material for charting routeing measures on nautical charts. The publication contains the precise coordinates and rules that the chart depicts graphically.
Q. How many parts does Ships' Routeing have?
Ships' Routeing is organized into eight parts: general provisions, traffic separation schemes, deep-water routes, areas to be avoided, other routeing measures, associated rules and recommendations, mandatory ship reporting systems, and archipelagic sea lanes.
