The Willamette River was a focal point for development because it provided transportation, energy, waste disposal, and water for crops and industry. In the 1860s, the federal government began eliminating side channels in order to improve navigability. As people built closer to the river, floods became a problem and so people armored the banks with rip rap and built dams.
Between 1850 and 1995, the total area of the river went from over 40,000 acres to around 20,000 acres.
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