Greater London Authority Act 1999

9 (1) The designation of—

(a) the boundaries of the charging area, and

(b) the roads in that area in respect of which charges are imposed,

shall be such as the authority making the charging scheme may determine, subject to any modifications made by the Authority.

(2) A TfL scheme may apply to an area which consists of the whole or any part of Greater London.

(3) A borough scheme may apply to an area which consists of the whole or any part of the area of the authority (or, in the case of a joint charging scheme, the combined areas of the authorities) making the scheme.

(4) A road shall not be subject to charges imposed by more than one charging authority at the same time.

(5) In the application of sub-paragraph (4) above in relation to a joint charging scheme, the authorities making the scheme shall be treated as if they together constituted a single charging authority.

(6) A TfL scheme may impose charges in respect of roads in the charging area, whether or not Transport for London is the traffic authority or the highway authority for those roads.

(7) A charging scheme must not impose charges in respect of a trunk road except with the consent of the Secretary of State.

(8) A borough scheme may impose charges in respect of GLA roads.