Just in case you chaps hadn't noticed, there was an interesting and relevant letter in 'The Times' on Saturday last about the rights of way between boats and vehicles.
Assuming that the flooding is ' the high seas or WATERS CONNECTED THEREWITH' under the International Regulations for Preventing Collisions at Sea, then there are clear rules.
Road Vehicles, being confined to the submerged roadway, shoud be regarded as being "Restricted in their ability to manoeuvre" and should therefore display from a mast three shapes in a vertical line: ball over diamond over ball. At night these are replaced by a vertical line of lights: red over white over red.
Immobilised vehicles would be treated as "vessels aground" and would be required to display three balls or three red lights in a vertical line.
Other vessels underway are then obliged to take avoiding action.
I trust that the above is of use to the general Mayhem Data Bank>>>>>>>>>>>>>>>>