Haw. Rev. Stat. § 174C-57

(a) A permittee may seek modification of any term of a permit. A permittee who seeks to change the use of water subject to the permit, whether or not such change in use is of a material nature, or to change the place of use of the water or to use a greater quantity of water than allowed under the permit or to make any change in respect to the water which may have a material effect upon any person or upon the water resource, shall make application pursuant to section 174C-51 in respect to such a change. Modification of one aspect or condition of a permit may be conditioned on the permittee's acceptance of changes in other aspects of the permit.

(b) All permit modification applications shall be treated as initial permit applications and be subject to sections 174C-51 to 174C-56; except that if the proposed modification involves an increase in the quantity of water not exceeding an average amount per month to be established by rule, the commission, at its discretion, may approve the proposed modification without a hearing provided that the permittee establishes that:

(1) A change in conditions has resulted in the water allowed under the permit becoming inadequate for the permittee's needs; or

(2) The proposed modification would result in a more efficient utilization of water than is possible under the existing permit.

(c) County agencies are exempt from the requirements of this section except where the modification involves a change in the quantity of water to be used or where the new use would adversely affect the quality of the water or quantity of use of another permittee. [L 1987, c 45, pt of §2]