This section has effect where, whether before, on or after the commencement date—
If and so far as a claim in respect of the highway or other public works relates to depreciation that would not have been caused but for the alterations or change of use, this Part of this Act shall, subject to subsection (3) below, have effect in relation to the claim as if the relevant date (instead of being the date specified in section 1(9) above) were—
as the case may be.
Subsection (2) above shall not by virtue of any alterations to an aerodrome apply to a claim in respect of physical factors caused by aircraft unless the alterations are runway or apron alterations.
Where a claim relates to such depreciation as is mentioned in subsection (2) above the notice of claim shall specify, in addition to the matters mentioned in section 3 above, the alterations or change of use alleged to give rise to the depreciation; and if and so far as the claim relates to such depreciation—
For the purposes of this section the carriageway of a highway is altered if, and only if—
and the reference in subsection (2) above to depreciation that would not have been caused but for alterations to the carriageway of a highway is a reference to such depreciation by physical factors which are caused by the use of, and the source of which is situated on, the length of carriageway which has been altered as mentioned in paragraph (a) above or, as the case may be, the additional carriageway and the corresponding length of the existing one mentioned in paragraph (b) above.
In this section "runway or apron alterations" means—
For the avoidance of doubt it is hereby declared that references in this section to a change of use do not include references to the intensification of an existing use.