The Flow of Water

1. The Flow of Water

2. The Water Cycle http://observe.arc.nasa.gov/nasa/earth/hydrocycle/hydro3.html

4. What is Water Budget? • balance in the water cycle means the average annual precipitation over Earth equals the amount of water that evaporates • the worlds water budget is in balance because precipitation = evaporation • local water budgets (that of a particular area) are NOT balanced due to temperature, presence of vegetation, wind, and amount and duration of rainfall

6. Water Conservation • each person in the U.S. uses 575 liters of water each day on average • bathing, washing clothes, dishes, brushing teeth, watering lawn, carrying waste away, drinking

8. Agriculture and industry use the greatest amount of water

9. 90% of this used water is returned to rivers, lakes, oceans, etc.

10. http://wwwga.usgs.gov/edu/wwvisit.html

11. What are the 2 ways to ensure water is there tomorrow? • conserve, conserve, conserve! • desalination (removing salt from the ocean water) Desalination Plant in Key West, FL

12. What are the parts of a River Systems?

13. watershed • land from which water runs off into streams (drainage basin)

14. Surf your watershed http://www.epa.gov/surf/ Know your watershed http://ctic.purdue.edu/kyw/kyw.html

15. tributaries • feeder streams that flow into a main river

16. divide • ridges or elevated regions of high ground that separate watersheds headwaters • beginning of a stream

18. Stream Erosion

19. channel • the path that a stream follows

20. bank bed

21. headward erosion • process of lengthening and branching of a stream

22. What is stream piracy? • the capture of a stream in one watershed by a stream with a higher rate of erosion in another watershed

23. Stage 1 - Beaverdam Creek, Gap Run, and Goose Creek flow eastward through the Blue Ridge and enter the Potomac.

24. Stage 2 - As the land is eroded downward, the three east flowing creeks do not have the power to erode as far through the Blue Ridge as the Shenandoah, Potomac system. The Shenandoah extends itself southward by headward erosion through the relatively high land west of the Blue Ridge. It eventually captures Beaverdam Creek.

25. Stage 3 - The capture of Beaverdam Creek added more discharge to the Shenandoah which was able to therefore erode more. Headward erosion leads to the capture of Gap Run. The water gaps where Beaverdam Creek and Gap Run used to flow through the Blue Ridge are left as wind gaps.

26. Stage 4 - Eventually Goose Creek is captured as well. Snicker's Gap, Ashby Gap, and Manassas Gap are left as wind gaps. As the land on either side of the ridge is eroded down together with the ridge summit, the relative elevation of the wind gaps becomes higher and higher.

27. What are the types of channel erosion? stream load: material carried by a stream

28. dissolved load: mineral matter transported in liquid solution

29. suspended load: particles of fine grains and silt suspended in the water

30. bed load: large, coarser sand, gravel, and pebbles that move along the bottom

31. Bed

34. What factors affect stream erosion? discharge velocity • volume of water moved by a stream within a given time • distance the water travels in a period of time gradient • steepness of a stream’s slope

37. River Systems

38. What are the features of a Youthful river? • straight • erodes rapidly • V-shaped • few tributaries • has waterfalls and rapids

42. What are the features of a Mature river? • meandering (winding) • slow erosion • U-shaped • lots of tributaries • holds lots of water

48. What are the features of an Old river? • gradient and velocity decreases • no more erosion • more meandering

50. What is a water gap? • notch formed where the stream has eroded its channel