Marine VHF radio is unnecessary on most of Britain’s quiet inland canals. On tidal rivers, estuaries and commercial waterways, however, it can become an important safety tool—and may sometimes be compulsory.
The precise rules depend upon the waterway, the vessel’s size and the proposed passage. Requirements should therefore always be confirmed with the relevant navigation or harbour authority before setting out.
Tidal Thames
The tidal Thames is the clearest example of a formal carriage requirement.
The Port of London Authority requires vessels measuring 13.7 metres—approximately 45 feet—or more to carry operational VHF equipment on most passages through its waters. There are limited exemptions, including for narrowboats navigating only between Brentford and Teddington.
Smaller vessels are strongly advised to carry VHF. Those without it may need to report to London Vessel Traffic Services by telephone before entering the tidal river.
At 58 feet, Priscilla would exceed the normal VHF threshold.
Tidal Trent, Yorkshire Ouse and Humber
The tidal Trent leads towards the Yorkshire Ouse and Humber Estuary, where narrowboats can encounter powerful tides, exposed water and substantial commercial traffic.
VHF is highly advisable on the tidal Trent and becomes increasingly important when travelling beyond Keadby towards Trent Falls and the Humber. Carriage requirements can vary according to the vessel and the waters entered, so the intended passage must be agreed with the relevant authorities.
Even where it is not compulsory for a particular narrowboat, travelling without VHF would remove an important means of receiving traffic information and communicating with locks, other vessels and port control.
River Severn and the Severn Estuary
VHF is recommended for more demanding passages on the tidal Severn and around the Severn Estuary, particularly when approaching Sharpness.
Sharpness Radio maintains VHF communication on Channel 13. Boats can also make some required contacts by telephone, so VHF should not be described as universally compulsory throughout the tidal Severn.
The combination of strong tides, limited stopping opportunities and commercial movements nevertheless makes it a valuable part of a properly prepared passage.
Bristol Channel and tidal River Avon
The Bristol Channel has one of the world’s largest tidal ranges and should be treated as serious coastal water.
Marine VHF is strongly recommended for narrowboats attempting passages involving the Bristol Channel, Avonmouth, Portishead or the tidal Avon. Harbour and lock facilities use VHF, although telephone alternatives may be available at some locations.
The exact equipment requirement should be confirmed as part of the passage plan.
Manchester Ship Canal
Pleasure craft must obtain permission and make advance arrangements before entering the Manchester Ship Canal.
The canal authority prefers communication by VHF because transmissions are recorded, but its published small-craft guidance also accepts mobile telephones. VHF is therefore highly desirable rather than universally mandatory for every pleasure craft passage.
Crews must still comply with the authority’s current transit conditions and remain contactable throughout the journey.
River Medway and Thames Estuary
The tidal Medway is a commercial navigation managed by Peel Ports, with Medway Vessel Traffic Services operating on VHF.
For an ordinary narrowboat, VHF is not automatically compulsory throughout the river. However, it is strongly advisable when navigating the lower Medway, approaching Sheerness or entering the Thames Estuary.
Local directions, notices to mariners and reporting requirements should be checked before travelling.
Clyde and Forth
The Clyde and Forth include commercial ports, controlled areas and busy shipping channels.
There is no simple rule requiring every leisure craft throughout both estuaries to carry VHF. Requirements and recommended channels depend upon the harbour area and proposed passage.
A narrowboat undertaking either journey should carry suitable communications equipment and consult the relevant harbour authority in advance.
Other tidal and commercial waterways
VHF may also be required or strongly recommended on parts of waterways including:
- The tidal Great Ouse
- The River Witham and approaches to the Wash
- The River Mersey
- The Ribble Link and River Douglas
- The tidal Medway and Swale
- Major harbour and port approaches
The rules are not determined merely by whether a river is tidal. Vessel length, commercial activity, local directions and the precise route can all affect the position.
Where VHF is usually unnecessary
A marine radio is not normally needed on ordinary canal journeys along waterways such as:
- The Grand Union Canal
- The Leeds and Liverpool Canal
- The Oxford Canal
- The Kennet and Avon Canal
- The Shropshire Union Canal
A charged mobile telephone is generally more useful for contacting the navigation authority or emergency services on these waterways.
VHF should not be carried casually without the necessary licensing and knowledge. The radio equipment must be appropriately licensed, and the operator must normally hold a recognised certificate such as the Short Range Certificate.
Planning for Priscilla
Priscilla will spend much of her time on waterways where VHF remains silent.
However, she is being designed with more demanding journeys in mind. A fixed, DSC-capable radio supported by a waterproof handheld unit would give us reliable communication on tidal rivers, estuaries and commercial waterways.
It is equipment we may rarely need—but on the passages where it matters, it could be indispensable.
Some of those passages form part of a much bigger plan.
For now, the destination remains our secret.