The Columbia River estuary received most of its ecological damage from which of the following sources?
A) dikes erected by farmers to prevent flooding
B) dredging of the river to accommodate boat traffic
C) hydroelectric dams
D) pollution due to soil erosion from logging
E) poor farming practices

Question

Quizplus · Accepted Answer

The Columbia River estuary received the most ecological damage from hydroelectric dams, as they alter the natural flow of the river, impede fish migration, and change sediment deposition patterns, among other impacts. While the other options (dikes, dredging, pollution from logging and poor farming practices) may have caused some damage, they are not the primary source of ecological damage in the estuary.

The Columbia River Estuary Received Most of Its Ecological Damage