Wallowa Lake Dam Rehabilitation and Water Management Act of 2004 - Authorizes the Secretary of the Interior, acting through the Commissioner of Reclamation: (1) to provide funding to the Associated Ditch Companies, Incorporated, to plan, design, and construct facilities needed to implement the Wallowa Lake Dam Rehabilitation Program; and (2) in cooperation with tribal, State, and local governmental entities, to participate in the planning, design, and construction of facilities needed to implement the Wallowa Valley Water Management Plan.
Limits the Federal share of the cost of activities authorized under this Act to 80 percent and prohibits the Federal Government from holding title to any facility rehabilitated or constructed under this Act. Permits only the Nez Perce Tribe to own and operate any facility located at the Dam for trapping and transportation of migratory adult salmon.