Section 3(b) in The Bihar Irrigation and Flood Protection (Betterment Contribution) Act, 1959
(b)in respect of an irrigation work or part of such work -(i)no betterment contribution shall be leviable except after four years of the completion of the irrigation work or part of such work, as the case may be; and(ii)no betterment contribution shall be levied if the cost of such work, not being a reservoir or storage dam, is less than rupees ten lakhs; and
