Boaters can still fill the domestic water tanks of their boats in areas where a hosepipe ban is in place. A Temporary Use Ban (TUB), often called a ‘hosepipe’ ban, does not prevent anyone from using a hosepipe to fill a domestic water tank that provides water for drinking, cooking, washing and sanitary uses.
The terms of a TUB or hosepipe ban are set out in law. The following activities are prohibited where a hosepipe ban is in place:
Watering a garden using a hosepipe
Cleaning a private motor-vehicle using a hosepipe
Watering plants on domestic or other non-commercial premises using a hosepipe
Cleaning a private leisure boat using a hosepipe
Filling or maintaining a domestic swimming or paddling pool
Drawing water, using a hosepipe, for domestic recreational use
Filling or maintaining a domestic pond using a hosepipe
Filling or maintaining an ornamental fountain
Cleaning walls, or windows, of domestic premises using a hosepipe
Cleaning paths or patios using a hosepipe
Cleaning other artificial outdoor surfaces using a hosepipe
In areas where a TUB has been imposed, restrictions are likely to remain in place until enough rain has fallen and river flows are back to a normal level. Most potable water taps on the waterways are supplied by the water companies that supply the rest of the local population and will be subject to any hosepipe bans. However, some water taps that boaters use are supplied from private boreholes or wells. The ability to continue to fill domestic water tanks from a hosepipe extends to boats, caravans, motorhomes and even tents, as long as the water is used domestically by the people who are living or holidaying in the boat, caravan etc. There are additional statutory and discretionary exemptions to the hosepipe ban set out in law, mainly to protect vulnerable and disabled people, Blue Badge holders, and the welfare of animals.
Most water company web sites have in-depth information about hosepipe bans; see for example
https://www.thameswater.co.uk/help/water-restrictions
and https://www.thameswater.co.uk/help/water-restrictions/legal-notice