Missouri River Enhancement and Monitoring Act of 2004 - Directs the Secretary of the Interior, acting through the Biological Resources Division of the U.S. Geological Survey, to establish a program at the River Studies Center of the Biological Resources Division to: (1) determine and monitor the biological and chemical characteristics of the Missouri River; (2) determine and monitor the interrelationship of those characteristics with the hydrology and geomorphology of the River; and (3) monitor and assess the biota, including threatened or endangered species, habitats, and water quality of the River.
Directs the Secretary of the Interior (the Secretary) to: (1) establish a database on River biota; and (2) make such database readily available to specified entities, including the Governors of affected States, the Secretaries of Agriculture and the Army, the Fish and Wildlife Service, the Administrator of the Environmental Protection Agency, the Missouri River Basin Indian tribes, and the public.
Requires the Secretary, acting through the Director of the Geological Survey, to: (1) review the program; (2) establish and revise the program's objectives, as necessary; and (3) report to Congress on the environmental health of the River.