Section 562(1) in The Calcutta Municipal Corporation Act, 1980
(1)Any improvement expenses under section 561 shall be a charge on the premises in respect of which or for the benefit of which such expenses are incurred, and shall be recoverable in such instalments and at such intervals as may be sufficient to discharge such expenses with interest thereon at such rate as may be determined by the State Government from time to time within such period, not exceeding thirty years, as the Corporation may in each case determine.