Where—
(a) land along the mean high water mark or the mark of mean high water springs of the sea, or along the bank of any river, or along the margin of any lake, has—
(i) been set aside as an esplanade reserve under this Part, or has been reserved for the purpose specified in section 289 of the Local Government Act 1974, or for public purposes pursuant to section 29(1) of the Counties Amendment Act 1961 or section 11 of the Land Subdivision in Counties Act 1946; or
then, notwithstanding that any land of the kind referred to in paragraph (a) has been previously reserved or set aside but subject to any rule in a district plan or any resource consent, there may, as a condition of consent under section 220(1)(aa), be set aside on the survey plan an esplanade reserve adjoining the land previously set aside or reserved, which shall—