What Physical Effect Do Most Bridges Have on the Streams

question 22

Multiple Choice

What physical effect do most bridges have on the streams they cross?

• A) They restrict flood flow on the floodplain, so water under the bridge is deeper and faster.
• B) They minimize flooding upstream because the water upstream moves more slowly.
• C) They decrease erosion under the bridge because they slow the water.
• D) They decrease water level just downstream because the water there moves more slowly.
• E) They cause vehicles crossing the bridge to get swept up in the flood.

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Definitions:

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