Section 32(2)(a) in Tamil Nadu Town and Country Planning Act, 1971
(a)Once in every ten years after the date on which the regional plan for an area comes into operation, the regional planning authority may, and if so directed by the Government shall, after carrying out such fresh surveys as may be considered necessary and in consultation with the Director, review the regional plan and make such modifications in such plan wherever necessary and submit the modified regional plan for the approval of the Government.