; or (II) the CAP system. (ii) Method of delivery The Secretary shall authorize the delivery of Hualapai Tribe CAP water under this clause to be effected by the diversion and use of water directly from the Colorado River in Arizona. (C) Contractual delivery The Secretary shall deliver the Hualapai Tribe CAP water to the Hualapai Tribe in accordance with the terms and conditions of the Hualapai Tribe water delivery contract. (D) Distribution of CAP NIA priority water (i) In general Except as provided in clause (ii), if, for any year, the available CAP supply is insufficient to meet all demands under CAP contracts and CAP subcontracts for the delivery of CAP NIA priority water, the Secretary and the CAP operating agency shall prorate the available CAP NIA priority water among the CAP contractors and CAP subcontractors holding contractual entitlements to CAP NIA priority water on the basis of the quantity of CAP NIA priority water used by each such CAP contractor and CAP subcontractor in the last year in which the available CAP supply was sufficient to fill all orders for CAP NIA priority water. (ii) Exception (I) In general Notwithstanding clause (i), if the available CAP supply is insufficient to meet all demands under CAP contracts and CAP subcontracts for the delivery of CAP NIA priority water in the year following the year in which the enforceability date occurs, the Secretary shall assume that the Hualapai Tribe used the full volume of Hualapai Tribe CAP water in the last year in which the available CAP supply was sufficient to fill all orders for CAP NIA priority water. (II) Continuation The assumption described in subclause (I) shall continue until the available CAP supply is sufficient to meet all demands under CAP contracts and CAP subcontracts for the delivery of CAP NIA priority water. (III) Determination The Secretary shall determine the quantity of CAP NIA priority water used by the Gila River Indian Community and the Tohono O’odham Nation in the last year in which the available CAP supply was