1. Part 3

2. Terminology Oxbow Lake- A lake that forms when a meander is cut off.
The lake is shaped like a “U”
Created by erosion and deposition on the curves of the meander

3. Formation of a Cutoff and Oxbow Lake

4. Meanders can turn into Oxbow lakes…here’s how

5. Ox Bow Lakes Neck of meander is gradually eroded
Once cut off, the water takes the quickest/shortest route
What’s left behind is the Ox Bow lake

6. .
More common than straight channels, meandering streams tend to form in gently sloping areas of unconsolidated sediments. Meanders in the Sevier River west of Yuba Reservoir, Utah.

7. Erosion occurs faster on the outer bank while deposition takes place on the inner curve (to form point bars). An oxbow lake is formed when the stream eventually cuts through the meander neck. (W.W. Norton)

8. Terminology Deposition- Dropping or putting down soil
Occurs on the inside edge of a meander where water moves slower
Erosion- Taking away soil
Occurs on the outside edge of a meander where water moves faster

9. Carrying capacity
Carrying capacity: The ability of streams to carry materials as they flow over the land
Sand and sediments
Dissolved gasses in the water
Dissolved solids
Living components
Animals, plants, algae

10. Sediment Transport in Rivers
Rivers & Streams carry sediment in 3 ways:
In solution (dissolved load)
In suspension (suspended load)
Scooting or rolling along bottom (bed load)

11. 1. Dissolved Load
Sediments that are dissolved in river water

12. 2. Suspended Load
Fine-grained sediment (like sand, silt, clay) that remains in the water during transportation
Usually what you see that makes a river look dirty
Most sediment carried by a stream is suspended
This amount increases dramatically during floods

13. 3. Bed Load
Heavier, coarse grained sediments that travel along the bottom of a stream.
Causes the most stream erosion!
Sediment may not move frequently

14. 6.2 The Work of Streams Floods and Flood Control
 A flood occurs when the discharge of a stream becomes so great that it exceeds the capacity of its channel and overflows its banks.
 Measures to control flooding include artificial levees, flood control dams, and placing limits on floodplain development.

15. Ohio River Flooding