Author Question: How does urbanization of the upstream drainage area for a floodplain affect the 100-year flood ... (Read 26 times)

mrsjacobs44 · **on:** Jul 13, 2018

How does urbanization of the upstream drainage area for a floodplain affect the 100-year flood level?
a. It lowers flood height, since the water runs through faster.
b. It raises flood height.
c. It decreases duration of the peak flood level.
d. The downstream extent of the highest flood level will be less.
e. There is no change; the flood level only depends on the total rainfall upstream.

Question 2

Why are flash floods more common in dry climates than wet climates?
a. The rainfall intensity is greater.
b. Individual storms last longer.
c. The soil is less permeable.
d. The river channels are not as deep.
e. The channel gradients are steeper, so the water flows faster.