(1) A local planning authority shall at all times keep under review the desirability of preparing a local plan for any part of the area for which it is the local planning authority and—
(a) may prepare a local plan for any part of that area:
Provided that—
(i) no local plan shall be prepared in respect of any part of an area for which a local planning authority has been appointed in terms of paragraph (d) of subsection (1) of section ten until the master plan prepared by that authority has become operative;
(ii) a local planning authority, other than a scheduled local planning authority, shall not prepare a local plan for any part of an area for which there is no operative master plan without first consulting the Director;
(b) shall, if so directed by the Minister, prepare a local plan for any part of such area:
Provided that the Minister may not issue a direction in terms of this paragraph without first consulting the local planning authority;
(c) shall, as soon as practicable after a master plan has become operative, prepare a local plan in respect of any area selected in terms of subsection (4) of section fourteen.
(2) Local plans may be prepared for different purposes for the same part of any area.
(3) A local plan shall, in relation to the planning area—
(a) formulate proposals for the coordinated and harmonious development, redevelopment or improvement and other use of land in that area, including measures for—
(i) the regulation of the use of land and the construction and use of buildings; and
(ii) the conservation and improvement of the physical environment, including the preservation of buildings of special architectural merit or historic interest; and
(iii) the movement of traffic therein, including the closure and diversion of any road; and
(iv) the phasing of any development, redevelopment or improvement; and
(b) concentrate on particular aspects or issues within the area that require attention and indicate the manner in which these are to be treated; and
(c) where a master plan has been prepared, set out in detail the manner in which the policy and general proposals of the master plan are to be implemented within that area.
(4) In formulating its proposals for a local plan the local planning authority shall— (a) ensure that the proposals conform generally with any regional plan or master plan, whether in operation or in the course of preparation; and
(b) have regard to any information and other considerations which appear to that authority to be relevant; and
(c) indicate the manner in which such proposals are justified by the studying terms of section thirteen. (5) A local plan shall consist of—
(a) a map of the planning area showing topographical details and property boundaries; and
(b) a written statement; with the proposals being illustrated by such additional maps, diagrams, illustrations and descriptive matter as the local planning authority considers appropriate.