ISP 203B FINAL UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
COMPLETE STUDY GUIDE
●● How do levees change rivers/streams? How do they impact
flooding?
Answer: They prevent floodwater from spreading over a floodplain.
They trap water inside a river channel. Levees protect areas behind
them.
●● What does a "100-year flood" really mean? What does "1% annual
chance flood hazard" mean?
Answer: Doesn't mean the flood will happen once every 100 years, it
means a flood of that size has a one percent chance of happening in any
year.
●● What are recurrence intervals?
Answer: The average time between floods of a given size
●● The three flood causes:
Answer: Heavy rainfall
Snowmelt
Storm surges/blocked rivers
, ●● Velocity
Answer: The speed that the water is moving in a river
●● Discharge
Answer: The amount of water flowing in a river at one specific time
●● Hydrograph
Answer: Graph that shows how a rivers water level changes over time
●● Flashfloods
Answer: Flash floods happen very quickly, caused by heavy rain, and
can be extremely dangerous.
●● Regional floods
Answer: Regional floods happen slowly and are caused by long periods
of rain.
●● Are wildfires natural? What impacts do they have on ecosystems?
Answer: Yes, wildfires are natural. They thin closely spaced trees,
reduce understory fuel, and allow different trees of different species and
ages to grow.
QUESTIONS AND CORRECT ANSWERS
COMPLETE STUDY GUIDE
●● How do levees change rivers/streams? How do they impact
flooding?
Answer: They prevent floodwater from spreading over a floodplain.
They trap water inside a river channel. Levees protect areas behind
them.
●● What does a "100-year flood" really mean? What does "1% annual
chance flood hazard" mean?
Answer: Doesn't mean the flood will happen once every 100 years, it
means a flood of that size has a one percent chance of happening in any
year.
●● What are recurrence intervals?
Answer: The average time between floods of a given size
●● The three flood causes:
Answer: Heavy rainfall
Snowmelt
Storm surges/blocked rivers
, ●● Velocity
Answer: The speed that the water is moving in a river
●● Discharge
Answer: The amount of water flowing in a river at one specific time
●● Hydrograph
Answer: Graph that shows how a rivers water level changes over time
●● Flashfloods
Answer: Flash floods happen very quickly, caused by heavy rain, and
can be extremely dangerous.
●● Regional floods
Answer: Regional floods happen slowly and are caused by long periods
of rain.
●● Are wildfires natural? What impacts do they have on ecosystems?
Answer: Yes, wildfires are natural. They thin closely spaced trees,
reduce understory fuel, and allow different trees of different species and
ages to grow.
