Willow Creek Winter Livestock Water Supply Act

Willow Creek Winter Livestock Water Supply Act - Authorizes the Secretary of the Interior to make payments to certain claimants relating to the loss of winter stock water from Willow Creek, Idaho.

Requires the Secretary to make such payments only if: (1) the claimant notifies the Secretary of the claim within one year of enactment of this Act; (2) the claimant was entitled to use, and did use, such water prior to December 31, 1979; (3) as a result of the operation of the Ririe Dam and Reservoir, the claimant may no longer take water from such channel during winter seasons; and (4) the claimant has not settled a claim against the United States for such loss.

Provides that the claimant may receive an amount equal to the costs incurred by such person in construction of a replacement water supply system.

Provides that acceptance of a payment under this Act shall constitute a full settlement.

Authorizes appropriations.