1. Human Impact on Beaches

2. Erosion and the Outer Banks
Read the article on Outer Banks beach erosion
As you read, highlight words or things that you do not know.
Once you finish reading, write a summary of the article.

3. Longshore Drift
When swimming in the ocean, have you ever wondered why you tend to be carried down the beach, away from your towel in an undertow?
The transportation of sediments along a coast at an angle to the shoreline

4. Preventing Beach Erosion
Sea Wall – a structure to protect a coast from erosion
Built parallel to the shore
Designed to shield the coast and defend property from the force of breaking waves

5. Causes the sediments in front of the wall to be swept in the ocean.
Further loss of beach prompts people to build a bigger, “better” wall to stop the erosion caused by the original seawall.

6. Preventing Beach Erosion
Breakwater - sediment movement is blocked from continuing along the coastline, disrupting the longshore transport.
Built parallel to the shore line
Protects boats from the force of large breaking waves by creating a quiet water zone near the shore

7. Preventing Beach Erosion
Groin - designed to trap sediments in an area of the beach.
disrupt the longshore transport
Perpendicular to the shore
the beach on the other side of the groin will continue to loose sediments

8. Preventing Beach Erosion

9. Preventing Beach Erosion
Beach Nourishment – sediment lost through long shore drift or erosion is replaced
Beach nourishment video

10. Preventing Beach Erosion
Vegetation – helps hold sand in place