A bill to authorize the Secretary of the Interior to construct, operate, and maintain an enlarged Bumping Lake, Supplemental Storage Division, Yakima project, Washington.

Authorizes the Secretary of the Interior to construct, operate, and maintain an enlarged Bumping Lake as part of the Yakima project, Washington, which shall consist of an enlarged Bumping Lake Dam, fish passage and protective facilities, fish hatchery, Tieton Dam modification, and other appurtenant water service facilities, necessary fishery equipment, and wildlife mitigation facilities.

Requires that: (1) the first 33,700 acre-feet of water from storage in the enlarged Bumping Lake be used for irrigation pursuant to exiting water rights; (2) 75 percent of any additional water from storage in the enlarged Bumping Lake be used for maintenance and enhancement of anadromous and resident fish resources in the Yakima River System; and (3) 25 percent of any additional water be used for irrigation, in integrating and coordinating the operations of the enlarged Bumping Lake into other features of the Yakima project, to effect the fullest, most beneficial and most economic utilization of the available water resources.

Directs the Secretary, prior to initiation of project construction, to: (1) secure the necessary permits from the State of Washington for water storage in, and operation of, an enlarged Bumping Lake; and (2) regulate releases from new storage to carry out the purposes of this Act through agreement with the State of Washington.

Directs the Secretary to prepare a detailed fish and wildlife compensation plan in coordination with the United States Forest Service and with appropriate agencies of the State of Washington.

Requires that irrigation repayment contracts shall provide for repayment within 50 years. Sets forth the formula to be used in determining the interest to be paid by non-Federal entities.

Authorizes appropriations as necessary to operate and maintain project facilities.

Provides that the feasibility study for the Kakima River Basin already authorized by law shall continue to include the Bumping Lake project, notwithstanding provisions of this Act.

Requires that the State of Washington be credited for funds it has provided for the project to satisfy any State matching fund requirements in any subsequently enacted legislation.