1. The hydrologic cycle

2. Sources of Earth’s water

3. RIVER Features Headwaters
Beginning of a stream; high elevation.

4. Watershed
Land from which water runs off into a stream.

5. Tributary
Feeder stream that flows into a main stream.

6. Divide
Elevated region that separates 2 watersheds.

7. Coastal Plain

8. Flood Plain Delineation Flood Plain Formation
Part of the valley floor that may be covered with water during a flood.
Flood Plain Delineation
Flood Plain Formation

10. Meander - E
Wide curve in a stream channel.

11. Erosion & Deposition along a meandering stream

12. Oxbow

13. Cut Bank - E
The area of active erosion on the OUTSIDE of a meander.

14. Point Bar - D
A crescent-shaped accumulation of sand and gravel deposited on the INSIDE of a meander.

16. Oxbow oxbow lake formation
Water remaining in an isolated meander in a floodplain.
oxbow lake formation

17. Upper Mississippi River (Missouri)

18. Delta - D
Fan-shaped deposit of sediments at the mouth of a stream formed when rivers erode and transport sediments. When the river slows down, it deposits sediments.

21. Common stream measurements
Gradient/Slope = rise = change in elevation
run distance
Discharge - how much water flows through a river in 1 second
Discharge = (l x w x d) / time
Greater discharge = more sediment it can carry & more erosion it can cause
Stream Load – size of sediment

22. Describe sediment carried by streams
Bed load- heavy sediment, skips along bottom
Suspended load- small particles, makes water look cloudy.
Dissolved load- minerals (or pollutants) in solution
Load Animation
Another Animation!
Stream Velocity & Load Deposition

23. Describe the 3 ways rivers erode sediment.
Headward – stream lengthening
Downcutting – mountainous areas form v-shaped valleys
Meandering –
Lateral – stream widening (occurs more than downcutting in flatter areas).
Formation of a V-Shaped Valley

24. How river systems change from young to mature!
Wide Channels
Large floodplains
Lateral erosion
Gentle slopes
Meanders, oxbows
Fine sediment
YOUNG
Narrow channels
Small floodplains
Downcutting
Steep slopes
Rapids, waterfalls
Coarse sediment
Life Cycle of a River Overview

25. Trace the path(s) that 99% of water travels through the Great Lakes watershed.

27. CANADA WISCONSIN MICHIGAN NEW YORK MINNESOTA IOWA PENNSYLVANIA
Great Lakes drainage basin
Most polluted areas, according to the Great Lakes Water Quality Board
“Hot spots” of toxic concentrations in water and sediments
Eutrophic areas
CANADA
WISCONSIN
MINNESOTA
IOWA
ILLINOIS
INDIANA
OHIO
PENNSYLVANIA
NEW YORK
MICHIGAN
Nipigon Bay
Thunder Bay
Silver Bay
St. Louis R.
Jackfish Bay
St. Mary’s R.
Spanish R.
Penetary Bay
Sturgeon Bay
Saginaw
Bay
Saginaw R.
System
St. Clair R.
Detroit R.
Rouge R.
Raisin R.
Maumee R.
Black R.
Rocky R.
Cuyahoga R.
Ashtabula R.
Thames R.
Grand R.
Niagara Falls
Niagara R.
Buffalo R.
St. Lawrence R.
Fig. 19.7, p. 484

28. Great Lakes Watershed

29. FLOODS Stream overflows channel Causes
Weather events
Dams break
(+) Provides “fertilizer” for floodplain
(-) Most destructive of all geologic hazards

30. Missouri & Mississippi Rivers (Satellite view near St. Louis)

31. Same satellite view during flooding in 1993

32. Describe human decisions that increase the risk of flooding.
Disturbing vegetation that uses water and returns it to the atmosphere before flooding occurs.
Building
Grazing animals
Farming practices like clear-cutting land
Cutting down forests

33. FLOOD CONTROL
Dams

34. Figure 13.12
Trade-offs: advantages (green) and disadvantages (orange) of large dams and reservoirs (Concept 13-3). The world’s 45,000 large dams (higher than 15 meters or 49 feet) capture and store about 14% of the world’s runoff, provide water for almost half of all irrigated cropland, and supply more than half the electricity used by 65 countries. The United States has more than 70,000 large and small dams, capable of capturing and storing half of the country’s entire river flow. Question: Which single advantage and which single disadvantage do you think are the most important? Why?
Fig , p. 325

35. Glen Canyon Dam, Page, AZ
(Lake Powell in background, Colorado River in foreground)