Rule 9: Narrow channels
- A vessel proceeding along the course of a narrow channel or fairway shall keep as near to the outer limit of the channel or fairway which lies on her starboard side as is safe and practicable.
- A vessel of less than 20 metres in length or a sailing vessel shall not impede the passage of a vessel which can safely navigate only within a narrow channel or fairway.
- A vessel engaged in fishing shall not impede the passage of any other vessel navigating within a narrow channel or fairway.
- A vessel shall not cross a narrow channel or fairway if such crossing impedes the passage of a vessel which can safely navigate only within such channel or fairway. The latter vessel may use the sound signal prescribed in Rule 34(d) if in doubt as to the intention of the crossing vessel.
- In a narrow channel or fairway when overtaking can take place only if the vessel to be overtaken has to take action to permit safe passing, the vessel intending to overtake shall indicate her intention by sounding the appropriate signal prescribed in Rule 34(c)(i). The vessel to be overtaken shall, if in agreement, sound the appropriate signal prescribed in Rule 34(c)(ii) and take steps to permit safe passing. If in doubt she may sound the signals prescribed in Rule 34(d).
- This Rule does not relieve the overtaking vessel of her obligation under Rule 13.
- A vessel nearing a bend or an area of a narrow channel or fairway where other vessels may be obscured by an intervening obstruction shall navigate with particular alertness and caution and shall sound the appropriate signal prescribed in Rule 34(e).
- Any vessel shall, if the circumstances of the case admit, avoid anchoring in a narrow channel.
What this means:
Rule 9: Narrow channels – Our plain English guide to help you understand & remember this rule.
Narrow channels are often found at the entrance to natural harbours and ports. They are usually buoyed, specifically to help commercial shipping navigate in and out safely.
We are not prohibited from using the channel, but we must do so without impeding vessels larger than 20 meters in length.
Rules for using a narrow channel
In addition to the requirement to keep clear of shipping confined to the channel, there are some core principles for anyone using them.
Specifically for small (less than 20m) vessels:
What constitutes a narrow channel?
The rule book doesn’t define a narrow channel, but we can be confident that any buoyed route into a harbour would be considered narrow. However, this does not preclude other sea areas from being deemed narrow. Of course, your view on this might change if you were the captain of a 300,000-ton oil tanker compared to a 25-foot sailing boat skipper. What is clear, though, is the English Channel does not constitute narrow, ever for the oil tanker captain.
Narrow channels in practice
Tap on the hotspots to explore three practical examples of a buoyed narrow channel.
Key Point:
Vessels less than 20m in length shall not impede a vessel confined to a narrow channel or separation scheme.
Always drive on the right, even if proceeding outside a main or defined channel.