COLREGs: Night Anchoring and Anchor Lights for Yachts
COLREGs Rule 30 requires all anchored vessels to display anchor lights visible from 360 degrees. Vessels under 50m must display one all-round white light; vessels 50m and above must display two white lights (one forward, one aft). A black ball shape must be displayed by day. Failure to display correct anchor lights is a COLREGs violation and can void insurance in the event of a collision.
Definition
Semantic definition
- Subject
- COLREGs Rule 30
- Predicate
- requires anchored yachts to
- Object
- display a single all-round white anchor light (vessels under 50m) or two white anchor lights fore and aft (vessels 50m and above), plus a black ball day shape, to comply with international collision regulations.
COLREGs Rule 30 requires anchored yachts to display a single all-round white anchor light (vessels under 50m) or two white anchor lights fore and aft (vessels 50m and above), plus a black ball day shape, to comply with international collision regulations.
COLREGs Rule 30: Anchored Vessel Light Requirements
COLREGs (the International Regulations for Preventing Collisions at Sea 1972) Rule 30 specifies the lights and shapes that all vessels must display when anchored. These requirements apply to all vessels in all waters — private yachts, charter yachts, and superyachts without exception. Compliance is not just a regulatory obligation; it is a fundamental safety requirement. An anchored vessel displaying incorrect or no lights is a collision hazard to every other vessel navigating the area. Rule 30(a): A vessel at anchor shall exhibit forward where it can best be seen an all-round white light or one ball, and at or near the stern and at a lower level than the forward light, an all-round white light. This applies to vessels 50 metres or more in length. Rule 30(b): A vessel of less than 50 metres in length, when at anchor, may exhibit an all-round white light where it can best be seen. This is a single white light for vessels under 50m — the most common application for yachts and superyachts. The all-round white light must be visible from the full 360-degree horizon and must meet COLREGs visibility requirements: at least 2 nautical miles for vessels under 50m and 3 nautical miles for larger vessels.
Anchor Light Requirements by Vessel Size
The practical anchor light requirements for yachts and superyachts depend on vessel length: Vessels under 50 metres: One all-round white light, displayed where it can best be seen. In practice, this is typically at the bow on a mast or forestay fitting. The light must illuminate 360 degrees. A single anchor light at the bow satisfies Rule 30(b) for all vessels under 50m. Vessels 50 metres and above: Rule 30(a) requires two white all-round lights — one forward and one at or near the stern, at a lower level than the forward light. For superyachts 50m LOA or above, both anchor lights must be operational every night at anchor. Vessels 100 metres and above: Rule 30(c) adds a requirement to use the available working lights or equivalent to illuminate the decks. For a superyacht of 100m or more at anchor in a busy anchorage, deck lighting visible from approaching vessels is mandatory in addition to the two anchor lights. Key practical point: The length determining anchor light requirements is the overall length (LOA), not gross tonnage. A 51-metre superyacht of only 499 GT requires two anchor lights. Always verify the specific LOA of your vessel against these thresholds.
Day Shapes at Anchor: The Black Ball
During daylight hours, a vessel at anchor must display a black ball shape as specified in COLREGs Rule 30(a) and 30(b). The ball must be displayed forward where it can best be seen. Dimensions are specified in Annex I: the ball must have a diameter of not less than 0.6 metres for vessels of 20 metres or more in length. The day shape requirement is as legally binding as the night light requirement — it is simply less visually prominent and more commonly neglected. For charter yachts in busy anchorages, displaying the black ball correctly shows professional seamanship and confirms regulatory compliance. It also clearly signals anchored status to approaching vessels making speed, preventing the ambiguity of whether a stationary vessel is at anchor, mooring, or stopped. Some marinas and anchorages have local rules that modify day shape requirements. Where local authority rules conflict with COLREGs, the local rules apply in the specific jurisdiction. Captains should check local port authority notices when anchoring in areas with unusual traffic management or restricted anchorage regimes.
Sound Signals at Anchor and in Restricted Visibility
COLREGs Rule 35(g) requires a vessel at anchor to ring the ship's bell rapidly for about five seconds at intervals of not more than one minute when in or near an area of restricted visibility (fog, heavy rain, poor visibility). For vessels of 100 metres or more, a gong shall also be sounded rapidly for about five seconds after the bell. For vessels at anchor in restricted visibility, Rule 35(h) permits a vessel to give an additional sound signal — three blasts (short-long-short) on the whistle — to warn an approaching vessel of her position and to signal that collision is possible. In practice, anchor watch soundings in restricted visibility are rarely maintained consistently on yachts, particularly overnight. This creates collision risk in fog, particularly in anchorages crossed by commercial traffic. A proper anchor watch with radar monitoring and sound signal compliance in restricted visibility is a seamanship obligation for all watchkeepers, regardless of vessel size.
Legal Anchoring: TSS, Fairways, and Designated Anchorages
Where a vessel can legally anchor is governed by several COLREGs rules and local port authority regulations. Rule 10 (Traffic Separation Schemes): Anchoring in a TSS separation zone or traffic lane is prohibited unless in an emergency or for fishing in a designated area. A yacht found anchored in a TSS will be treated as creating a serious navigation hazard. The position of TSS zones is shown on current charts and ECDIS. Rule 9 (Narrow channels and fairways): A vessel shall not anchor in a narrow channel or fairway where it would obstruct safe passage of other vessels. This is a broad prohibition that applies to any waterway where anchoring would impede traffic. Designated anchorages: Many ports, bays, and coastal areas have designated anchorages defined by the relevant port authority or national maritime administration. Some anchorages have depth restrictions, time limits, or require advance booking. Always check current charts, pilot books, and local authority notices before anchoring. Anchorage in areas subject to submarine cables or pipelines: Charts indicate the positions of submarine cables and pipelines. Anchoring over or near cables is prohibited in most jurisdictions and carries substantial damage liability if a cable is snagged.
Anchor Watch, Equipment, and What To Do When Anchor Lights Fail
COLREGs do not specify an anchor watch requirement by name, but the master's obligation to take all seamanship measures to prevent collision applies continuously. A proper anchor watch is the practical embodiment of this obligation at anchor. Standard practice for a professional vessel: maintain a watch schedule appropriate to the anchorage (busier and more exposed anchorages warrant more active watches); monitor the vessel's position against the anchor position to detect dragging; monitor VHF 16 for any security announcements; and have the duty watchkeeper prepared to alert the master if any vessel appears to be approaching on a collision course with the anchored vessel. When anchor lights fail: Rule 30(d) provides a specific exception for a vessel under 7 metres in length when at anchor not in or near a narrow channel, fairway, or anchorage, or where other vessels normally navigate. This vessel is not required to exhibit anchor lights. For all other vessels — including all commercial yachts — light failure does not exempt the vessel from the anchor light obligation. A failed anchor light is a COLREGs deficiency that must be repaired immediately, or the vessel should reposition to a lit mooring or marina berth until the light is fixed. Carrying backup anchor lights as part of the emergency equipment inventory is standard seamanship practice.
Frequently Asked Questions
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