What is the role of a drainage basin?

2. What is the role of a drainage basin? Drain water from rivers or streams. Collect rain and other precipitation to drain into rivers or streams. Allow a place for flood waters to be absorbed instead of going into larger rivers. Hold water to evaporate instead of going into rivers or streams. Drain water into the ocean through an intricate series of underground tunnels.

3. What is the role of a drainage basin? Drain water from rivers or streams. Collect rain and other precipitation to drain into rivers or streams. Allow a place for flood waters to be absorbed instead of going into larger rivers. Hold water to evaporate instead of going into rivers or streams. Drain water into the ocean through an intricate series of underground tunnels.

4. The figure is most likely a cross section of a river at the base level. flowing uphill. entering the ocean. near its headwaters. where a tributary enters.

5. The figure is most likely a cross section of a river at the base level. flowing uphill. entering the ocean. near its headwaters. where a tributary enters.

6. Along the same river with no additions or deletions of flow, which situation has the greatest discharge? A narrow channel at the head of a stream A narrow channel at the base level of a stream Not enough information to tell A wide channel at the base level of a stream The discharge will be the same

7. Along the same river with no additions or deletions of flow, which situation has the greatest discharge? A narrow channel at the head of a stream A narrow channel at the base level of a stream Not enough information to tell A wide channel at the base level of a stream The discharge will be the same

8. The continual migration of meandering rivers is a result of the construction of floodplains. movement of Oxbow lakes. faster flow on the inside and slower flow on the outside of the bend. continual erosion of cutbanks and deposition on point bars. the creation of pools and riffles.

9. The continual migration of meandering rivers is a result of the construction of floodplains. movement of Oxbow lakes. faster flow on the inside and slower flow on the outside of the bend. continual erosion of cutbanks and deposition on point bars. the creation of pools and riffles.

10. Which does not play a role in flooding? The amount of humidity in the atmosphere How quickly surface runoff reaches the river The amount of moisture in the soil when the precipitation starts Presence of frozen ground or accumulated snow Rate of precipitation infiltration into the earth

11. Which does not play a role in flooding? The amount of humidity in the atmosphere How quickly surface runoff reaches the river The amount of moisture in the soil when the precipitation starts Presence of frozen ground or accumulated snow Rate of precipitation infiltration into the earth

12. Saying that a flood is a 100-year flood means that it takes 100 years for a flood of this size to develop in an area. there is a 1 percent probability that this size of flood will occur in any given year. it will occur exactly every 100 years in a specific area. there is no such thing as a 100-year flood, you cannot interpolate flood data that far out. every 100 years an area may be flooded.

13. Saying that a flood is a 100-year flood means that it takes 100 years for a flood of this size to develop in an area. there is a 1 percent probability that this size of flood will occur in any given year. it will occur exactly every 100 years in a specific area. there is no such thing as a 100-year flood, you cannot interpolate flood data that far out. every 100 years an area may be flooded.

14. What distinguishes flash floods from downstream floods? Flash floods are only common with large rivers. Flash floods are less dangerous than downstream floods. Flash floods are more dangerous than downstream floods. Flash floods occur in the upper part of the basin. Flash floods are commonly associated with long duration storms.

15. What distinguishes flash floods from downstream floods? Flash floods are only common with large rivers. Flash floods are less dangerous than downstream floods. Flash floods are more dangerous than downstream floods. Flash floods occur in the upper part of the basin. Flash floods are commonly associated with long duration storms.

17. With the addition of levees (see figure), how does the natural floodplain change? The floodplain area is increased. The area of wetlands is decreased. The floodplain does not change, there are just levees now. The discharge increases. The river channel remains the same.

18. With the addition of levees (see figure), how does the natural floodplain change? The floodplain area is increased. The area of wetlands is decreased. The floodplain does not change, there are just levees now. The discharge increases. The river channel remains the same.

19. The figure shows the change in flood damage and flood-control expenditures over the years. What has caused these trends? Rivers have flooded more often now than in the past. There has been an increase in development on floodplains. Not enough money has been spent on flood-control. There are more rivers and streams now than in the past. Political policies have not allowed much flood-control expenditures.

20. The figure shows the change in flood damage and flood-control expenditures over the years. What has caused these trends? Rivers have flooded more often now than in the past. There has been an increase in development on floodplains. Not enough money has been spent on flood-control. There are more rivers and streams now than in the past. Political policies have not allowed much flood-control expenditures.

21. Which is not a factor that affects the damage caused by floods? The time between floods Effectiveness of forecasting, warning, and evacuation Land use on the floodplain Season of the year the flooding occurs Depth and velocity of floodwaters

22. Which is not a factor that affects the damage caused by floods? The time between floods Effectiveness of forecasting, warning, and evacuation Land use on the floodplain Season of the year the flooding occurs Depth and velocity of floodwaters

23. Which is not an effect of flooding? Damage caused by swift currents or debris Considerable loss of soil and vegetation from erosion Disease Fires Earthquake

24. Which is not an effect of flooding? Damage caused by swift currents or debris Considerable loss of soil and vegetation from erosion Disease Fires Earthquake

25. What makes flooding a natural hazard? No levees built to protect the area If it is a flash flood People live or build structures on the floodplain Flood discharge greater than 15 cubic meters per second Flood stage over 3.5 meters

26. What makes flooding a natural hazard? No levees built to protect the area If it is a flash flood People live or build structures on the floodplain Flood discharge greater than 15 cubic meters per second Flood stage over 3.5 meters

27. Which is not a natural service function of a flood? Improve the fishing supply Create natural fertile agricultural land Help keep debris from accumulating Wash away fertilizer used in farming Move food downstream for aquatic life survival

28. Which is not a natural service function of a flood? Improve the fishing supply Create natural fertile agricultural land Help keep debris from accumulating Wash away fertilizer used in farming Move food downstream for aquatic life survival

29. How did the building of the Glen Canyon Dam affect the Colorado River? Made rapids more dangerous because boulders are not naturally moved downstream. Reduced the mean annual flood. Disappearance of sandbars. Growth of vegetation not previously present. All of these are affects of the dam.

30. How did the building of the Glen Canyon Dam affect the Colorado River? Made rapids more dangerous because boulders are not naturally moved downstream. Reduced the mean annual flood. Disappearance of sandbars. Growth of vegetation not previously present. All of these are affects of the dam.

31. What is a problem with urbanization when it comes to flooding? Bridges increase the flow of small streams. The impervious surfaces can increase the frequency of low and intermediate floods. It can increase the lag time between rainfall and runoff. The amount of runoff is reduced. Reduces the amount of algae in streams.

32. What is a problem with urbanization when it comes to flooding? Bridges increase the flow of small streams. The impervious surfaces can increase the frequency of low and intermediate floods. It can increase the lag time between rainfall and runoff. The amount of runoff is reduced. Reduces the amount of algae in streams.

33. Which is not a way that humans can increase the frequency and magnitude of flooding? Generate more erosion from creation of cropland from forests Build storm sewers to carry runoff to streams Create more green spaces in a city Build of low bridges with supports that are close together Paving almost everything in a city (roads, sidewalks, etc.)

34. Which is not a way that humans can increase the frequency and magnitude of flooding? Generate more erosion from creation of cropland from forests Build storm sewers to carry runoff to streams Create more green spaces in a city Build of low bridges with supports that are close together Paving almost everything in a city (roads, sidewalks, etc.)

35. Which is not a way we have tried to minimize flood hazards? Building levees and flood walls National adoption of strong floodplain regulation policies Straightening the river channel Building on-site storm water retention basins Widening the river channel

36. Which is not a way we have tried to minimize flood hazards? Building levees and flood walls National adoption of strong floodplain regulation policies Straightening the river channel Building on-site storm water retention basins Widening the river channel

37. What is a major problem with flood-control measures? There is not enough land to build them They never work to control the flooding They take away land for new development They tend to encourage more people to move into the floodplain They create a scenic eye-sore so no one wants to live there

38. What is a major problem with flood-control measures? There is not enough land to build them They never work to control the flooding They take away land for new development They tend to encourage more people to move into the floodplain They create a scenic eye-sore so no one wants to live there

39. Which is not an argument by opponents of natural stream modification? Cutting trees increases the aesthetics by permitting better views of the stream Straightening or modifying the streambed can affect peak flow Cutting tress eliminates shade important for aquatic life Draining wetlands can eliminate habitats for some animal species Converting a stream from meandering to straight, ruins the aesthetics

40. Which is not an argument by opponents of natural stream modification? Cutting trees increases the aesthetics by permitting better views of the stream Straightening or modifying the streambed can affect peak flow Cutting tress eliminates shade important for aquatic life Draining wetlands can eliminate habitats for some animal species Converting a stream from meandering to straight, ruins the aesthetics

41. What is a difference seen between a natural stream and a channelized stream? A channelized stream will have less riffles because there are no curves to create them. A natural stream will experience higher temperature changes since it is not exposed to the sun all day. A channelized stream allows for more aquatic life because there are few if any large rocks to take up space. A channelized stream will maintain a more consistent water depth throughout the year since its streambed is more level. A natural stream has a more diverse aquatic life since there are varying water velocities.

42. What is a difference seen between a natural stream and a channelized stream? A channelized stream will have less riffles because there are no curves to create them. A natural stream will experience higher temperature changes since it is not exposed to the sun all day. A channelized stream allows for more aquatic life because there are few if any large rocks to take up space. A channelized stream will maintain a more consistent water depth throughout the year since its streambed is more level. A natural stream has a more diverse aquatic life since there are varying water velocities.

44. The figure shows a zoning map before and after the implementation of flood regulations. What is most likely not a reason for the regulations? Reduce the loss of lives and property damage during an annual flood Could eliminate the need for other flood control measures Return the much sought after land to the government for their own development Removes development from areas most prone to flooding Restores the natural stream environment

45. The figure shows a zoning map before and after the implementation of flood regulations. What is most likely not a reason for the regulations? Reduce the loss of lives and property damage during an annual flood Could eliminate the need for other flood control measures Return the much sought after land to the government for their own development Removes development from areas most prone to flooding Restores the natural stream environment