Week 6 Quiz: Floods

Which of the following loads are most likely to consist of heavy rocks and boulders? A) Bed load B) Suspended load C) Dissolved load D) Structural load E) Buoyant load

A) Bed load

What should you do during a flood? A) Move to higher ground away from the river B) Wade into the water to see how deep it really is C) Drive your car through water to get to safely D) Swim across water to a safe location E) Go to a bridge and watch the water rise

A) Move to higher ground away from the river

Where does a meandering river run the fastest? A) On the outside of a bend B) On the inside of a ben C) All parts of a meandering river run at similar speeds D) Near the point bars

A) On the outside of a bend

If you are standing of the middle of a river and look at either side, you might see tall earthen hills. What are they and what do they do? A) They are levees and they hold in floodwaters B) The are drains and they drain water to the city C) They are dams and let water out slowly D) The out cutbanks and they hold in water

A) They are levees and they hold in floodwaters

What is the role of a drainage basin? A) Rivers empty into a drainage basin, which represents a lake or an ocean B) A drainage basin is the area drained by a river and all its tributaries C) A drainage basin is very permeable soil into which flood waters seep instead of going into the river D) A drainage basin is very impermeable soil, where flood waters are held and eventually evaporate instead of going into a river E) A drainage basin is a set of underground tunnels that drain water into the ocean

B) A drainage basin is the area drained by a river and all its tributaries

What is the floodplain? A) The area around a river that is the ultimate limit to how far it will ever flood B) A flat area next to the river carved out by the rivers C) The steep sides of the river channel that holds in the water D) Earthen mounds that run parallel to the river and hold the water during floods E) A triangular shaped depots that forms when a river flows into the ocean

B) A flat area next to the river cared out by the rivers

What distinguishes flash floods from downstream floods? A) Flash floods are caused by thunderstorms, downstream floods do not involve lightning and thunder B) Flash floods occur in the upper part of a drainage basin, downstream floods occur in the lower part of the drainage basin C) Flash floods don't really involve any danger, downstream floods are extremely dangerous D) Flash floods are only common with large rivers, downstream floods generally involve much smaller rivers

B) Flash floods occur in the upper part of a drainage basin, downstream floods occur in the lower part of the drainage basin

What is the stage of the river? A) Volume of water that flows past a point over time B) Height of water that is flowing C) Age of the river D) Elevation of the top of the river valley E) Length of the river

B) Height of the water that is flowing

How would a river in an area changed from forest to farmland react to changes? A) Decreased amounts of sediment would increase the gradient of the stream B) Increased amounts of sediment would increase the gradient of the stream C) Decreased amounts of sediment would decrease the gradient of the stream D) Increased amounts of sediment would decrease the gradient of the stream E) The change of the land use would have no effect

B) Increased amounts of sediment would increase the gradient of the stream

Living near a dam is very safe because you will never have to worry about flooding. True or false

False

Tributaries are smaller streams which drain into larger rivers. True or false

False

A narrow river usually runs faster than a wider one. True or false

True

After a flood, you should be sure to wash everything that has been in touch with river water. True or false

True

If the discharge of a river is constant and the river channel suddenly widens, then the velocity of the river will decrease. True or false

True

Insurance and building codes are two important ways that government can protect property from disaster in a flood. True or false

True

Virtually all areas of the U.S. have some risk of flooding. True or false

True

What would the longitudinal profile of a river flowing from a gentle valley into an ocean look like? A) A steeply downward sloping line B) A steeply upward sloping line C) A gently downward sloping line D) A gently upward sloping line E) An upward sloping and then downward sloping line

C) A gently downward sloping line

What two parameters are plotted in a hydrographic? A) Cross-sectional area vs. stage B) Stage vs. elevation C) Discharge vs. time D) Stage vs. gradient E) Velocity vs. discharge

C) Discharge vs. time

Which homes built on the floodplain are most likely to sustain the greatest damage? A) Houses outside the floodplain B) Houses within the 100 year floodplain but outside the 20 year floodplain C) Houses within the 20 year floodplain D) All houses within the floodplain have an equal chance to sustain similar amounts of flood damage

C) Houses within the 20 year floodplain

Which rivers have the highest gradient? A) Rivers near their base level B) rivers near the ocean C) Rivers in gentle valleys D) Rivers moving down mountains

D) Rivers moving down mountains