PA3660-Coastal Hazard Assessment - 4 arakoon

Project related

Proyat

HaskoningDHV

 

Figure 6-1 ETA 602 location in reference to 4-6 Arakoon Crescent, Sunshine Beach

6.2.2 Short-term Erosion (C)

The Department of Environment and Heritage Protection (2013) recommends the calculation of short-term
erosion based on a 100-year ARI storm event using the method developed by Vellinga (1983). The
equation developed by Vellinga is as follows;

 

(22)y= oa7|(28)'.( wr 13) -200 Equation 2

Hos Hos 0.0268.

Where

H,, = Deep water significant wave height (meters)
w= Fall velocity of sand (meters/second)

x= The distance from the dune foot (meters)
y= Depth below storm surge (meters)

The relationship between sediment grain size and fall velocity has been derived from laboratory tests and
is given by the following equation (Vellinga, 1983).

logio(4/w) = 0.476 (logig D)? + 2.18 logyg D+ 3.19 Equation 3

Where
w= Fall velocity of sand (meters/second) in still water of 10°C
D= The grain size of the sand (meters)

11 April 2024 4-6 ARAKOON CRESCENT, SUNSHINE BEACH PA3660-RHD-XX-ZZ-RP-Z-0001 26