Mangawhai-pakiri Flashcards
What is sand used for
Construction,glass manufacturers,beach replenishment
Where is the Mangawhai- pakiri coastline
East coast of new Zealand s north peninsula in Auckland
What is ten sand from Mangawhai- Pakiri used for
Construction
What is the population of Auckland
1.5 million 1/3 NZ population
How much GDP does Auckland count for
35 percent
How many people visited Auckland in 2015
2.3 million foreign visitors
How long is ten Mangawhai-pakiri coastline
20km
How long has dredging on the coastline gone on for
70 years
How much sand has been extracted between 1994 and 2004
165,000 m^3
When did mining stop at Mangawhai beach
2005
How much sand was extracted at Pakiri beach
75,000 m ^ 3
When did mining stop on Pakiri beach
2020
What is some of the sand used for
Replenishing Auckland’s tourist beaches
Do rivers provide any sediment at mangawhai and pakiri
No there are very few rivers
What type of system is Mangawhai-Pakiri (open or closed)
Closed as there are no rivers adding sediment
How much do extraction rates exceed deposition by
5x
How are coastal land forms affected
Beaches are wider and flatter don’t absorb energy as well. More susceptible to wind erosion as the vegetation goes
What happened in 1978 mangawhai and pakiri
28 metre breach at the base of the Mangawhai beach led to sedimentation of the harbour (shallower water) more risk of flooding
By the end of the century how much will the coast retreat by
100 metres
