Beach Nourishment

Question 1

Beach nourishment cycles exist because…

Answer 1

There is a chronic erosion problem in an inhabited area.

Question 2

Good definition for a need for human-landscape coupling?

Answer 2

Strongest where fluvial, oceanic or atmospheric processes render significant stretches of human occupied land vulnerable to large changes and damage, and where market processes assign value to the land and drive measures to protect it from damage.

Question 3

How long do these processes of human-landscapes tend to operate?

Answer 3

Over the (human) medium scale of perhaps many years to decades, over which landscapes become vulnerable to change and over which markets drive investment in structures, evaluate profits from those investments, and respond to changes in conditions.

Question 4

Netherlands -> national scale intervention

Answer 4

9 M people, 400 B euros (65% GNP), most @ elevations < SL
Dykes + dunes + BN + barrages + barriers + “engineered” marshes
Big Flood of 1953 -> Dutch Delta Plan
“And of course, the number of people and the value of property that need to be protected from flooding has grown steadily.”

Question 5

Netherlands beach nourishment programme

Answer 5

Expand northern coastward seaward by ~km -> land for beach reserves, nature and recreation (worth around 3B euros/ yr)

Cost of doing nothing = 3.7T euros; single dyke failure could = 10-50B euros…

Question 6

With beach nourishment, you always have to have….

Answer 6

Re-nourishment

Question 7

Masked erosion

US East Coast SLR

Answer 7

SLR acceleration since 1990

SLR acceleration -> (more) coastal erosion…right

Question 8

According to Hapke et al., 2013, what influence appears to override the geomorphological signal of shoreline behaviour?

Answer 8

The influence of development- reduction in the percentage of eroding coast in the past two to three decades.

Question 9

Miami example

Answer 9

Dramatic example

Before and after beach nourishment

Had a very narrow beach with waves almost up to the hotel fronts

Sediment was then deposited on the beach generating a wide beach
There is a groyne field – but this is buried when the beach has just been replenished

Methods - A slurry pipe distributed sediment which is then ploughed around by diggers – can also be done with a barge right inshore

Because of the salt water and risks – there is a pretty short lifetime for the machinery

Question 10

Florida example

Answer 10

Florida – From no beach to a beach after beach nourishment
Implications – During the construction, the machinery isn’t very good for habitats

Few people have studied the ecology of beach nourishment
Why – People use beaches, so by nourishing them they can use them

Beach tourism is a big financial and economic engine
Partly why it exists as a management practice

Question 11

What do they do in North Carolina?

Answer 11

You cant pour concrete onto the ocean side
So they put massive sand bags down in front of real estate
It prevents erosion etc

Question 12

Netherlands example

Answer 12

– they are a hold the line program
Trying to input artificial dunes
The largest beach nourishment in the world – mega nourishment