Subject
- Abandoned mined lands reclamation -- Social aspects -- Oregon -- Willamette River Valley1
- Aggregate industry -- Environmental aspects -- Oregon -- Willamette River Valley1
- Climatic changes -- Northwest, Pacific -- Evaluation1
- Climatic changes -- Oregon -- Evaluation1
- Climatic changes -- Oregon -- John Day River, Middle Fork -- Computer simulation1
- Columbia River Treaty (1961 January 17)1
- Floodplain management -- Social aspects -- Oregon -- Willamette River Valley1
- Land use, Rural -- Social aspects -- Oregon -- Willamette River Valley1
- Natural resources -- Multiple use -- Oregon -- Willamette River Valley1
- Stream restoration -- Oregon -- John Day River, Middle Fork1
- Water temperature -- Oregon -- John Day River, Middle Fork -- Computer simulation1
- Watershed management -- Columbia River Watershed1
- Watershed management -- Columbia River Watershed -- Government policy1
- Watershed management -- Columbia River Watershed -- International cooperation1