U5L2 Shorelines Management Strategies Flashcards
What is the dentition of beach erosion?
The movement of sand and sediment from off the shore to deeper waters
What are some beach erosion management strategies?
- jetties
- groins
- seawalls
- coconut coir logs
How are jetties and groins similar?
They are both hard structures built perpendicular to the shorelines and they both protect erosion caused by waves and currents.
How are groins and jetties different?
Groins tend to be smaller and shorter structures, while jetties can reach farther out into the ocean.
What are the downside of jetties and groins?
While both are viable management options, they can actually cause some erosion in places as sand piles up on the updrift side of the structure, resulting in less sand on the downdrift side.
How to combat the downside of jetties?
Erosion caused by jetties can be severe with unintended consequences for beaches on the downdrift side of the jetty. Because of this, multiple jetties have to be built to help reduce this effect.
What are seawalls?
They are structures built at the water’s adage or slightly inland.
What do seawalls protect beaches from?
Rising tides, strong waves, and tsunamis.
How does a seawalls work?
As a wave crashes into a sea wall, the energy of the wave is reduced causing it to pick up and erode lass sand.
What are coconut coir logs?
They are placed along shorelines to help reduce beach erosion.
What are coconut coir logs made out of?
They are round logs made of coconut fibers. They are biodegradable, safe for the surrounding wildlife.
How do coconut coir logs help sea grass form?
They can help to stabilize the area long enough for natural seaters to establish a strong root structure. However, this can take a while.
What is beach nourishment?
Adding sand and sediment to a beach.
What does beach nourishment help with?
Create new natural environments, rebuild sand dunes, and protect sediment volume during sea level rise.
What are the downsides of beach nourishment?
Beach nourishment is a very expensive strategy. It requires the pumping or trucking of sand onto beaches. In some cases, this can cost millions of dollars. It is also not a long-term solution to the problem of erosion.
