18(1)The navigation officer may give directions for all or any of the following purposes—E+W
(a)for regulating the time at which and the manner in which any vessel may enter, leave, or lie in the navigation area;
(b)for regulating the position, mooring, unmooring, placing or removing of any vessel while it is in the navigation area;
(c)for regulating the position in which any vessel may, while in the navigation area, take in or discharge cargo or ballast or take in or land passengers;
(d)for regulating the manner in which any vessel entering the navigation area may be dismantled, either for the safety of the vessel or for preventing injury to other vessels or property or to any part of the navigation area;
(e)for removing unserviceable vessels and other obstructions from the navigation area and keeping it clear;
(f)for prohibiting the mooring or anchoring of any vessel in any particular part or parts of the navigation area;
(g)for regulating the manner in which vessels are to navigate while within the navigation area.
(2)In any case which appears to the navigation officer to be an emergency, general directions given under this paragraph may be expressed to be applicable to all vessels or to all vessels of a particular class.
(3)Directions under this paragraph shall be communicated to the person having charge of the vessel concerned by being given to him in writing unless it is not reasonably practicable to do so, in which case they shall be communicated to him in such manner as the navigation officer considers appropriate.
(4)The navigation officer shall not exercise his powers under this Schedule in any way which interferes with the discharge by the Commissioners of Her Majesty’s Customs and Excise of any of their functions.
(5)Where a vessel is within the navigation area, the person who has charge of it shall comply with any direction given under this paragraph which—
(a)applies in relation to his vessel; and
(b)has been communicated to him by or on behalf of the navigation officer;
and any such person who fails (without reasonable excuse) to do so shall be guilty of an offence and liable on summary conviction to a fine not exceeding level four on the standard scale.