1. Beach Protection Notes

2. Causes of Sand Depletion
1. Waves
2. Wind
3. Storms Hurricanes & Nor’easters cause the most erosion.

3. When storm waves carry sand off of the beach and deposit it in an offshore sandbar, it results in a very narrow beach. When gentle waves carry offshore sand back to the beach, it results in a wide, broad beach.
Winter Beach
Summer Beach

4. Winter Beach
Summer Beach

5. Average rate is 25-30cm per century, if current studies are credible.
Rising Sea Level
Average rate is 25-30cm per century, if current studies are credible.
Global Warming
The melting of glaciers & ice sheets would causes a rise
in sea level, should a sustained global warming occur.
Longshore Current
A current that flows parallel to the coast, which
transports sand down a beach in the same direction
as the current.

6. Beach Erosion Solutions
Groin or Jetty
Description A structure protruding into the
ocean perpendicular to the coast.
Pros Stops longshore drift from carrying sand away from a localized area of beach.
Cons Causes severe depletion of sand on the downside of the structure.

7. Groin or Jetty

8. Jetty at Rudy Inlet - Virginia Beach, VA

9. Description An upright wall that runs parallel along the coast.
Seawall
Description An upright wall that runs parallel along the coast.
Pros Intended to protect uplands from wave erosion.
Cons Causes severe erosion of the beach in front of it.

10. Seawall

11. Description An offshore barrier. Japan has many.
Breakwater
Description An offshore barrier. Japan has
many.
Pros Protects the shore from the full
impact of waves.
Cons Not very pleasant to look at.

12. Breakwaters

13. Breakwaters at Willoughby Spit - Norfolk, VA

14. Description A breakwater that does not break
Underwater Breakwater
Description A breakwater that does not break
the surface & acts as a coral reef.
Pros Protects the shore from wave
energy.
Cons Presents hidden obstacles to surfers & boaters.

15. Underwater Breakwater

16. Description Pumping offshore sand back to the beach.
Beach Nourishment
Description Pumping offshore sand back to the beach.
Pros Presents no problems to the beach.
Cons Very expensive & needs to be done about every 5 years. The U.S. spends $1.25 billion/year.

17. Beach Nourishment