A brief pictorial history of Noosa Main Beach and Estuary reviewing coastal management from first nations through first settlement to current day - with a brief overview of coastal management theory. Sources include Nancy Cato's Noosa Story and other publications featured in slides.

1. The Shifting Sands of
Noosa
Estuaries & Coasts
Did we manage in the past?
Are we managing now?
Can we manage in the future? 1

2. OUTLINE
 Geologic and historic timeline of Noosa
coasts and estuaries
 Geo 100 – Understanding coastal and
estuary processes
 The past and present of coastal
‘management’ interventions
 The future challenges for Noosa coasts
and estuaries
2

3. The Story Line
Apologies to Jules Verne
3
YEARS

4. Mixing the Metaphor
Captain Nemo Lost Nemo
4

5. 20 000 years Over the Sea
5
The oldest dated evidence of occupation in South East
Queensland comes from Stradbroke Island 20,560 +/-250
BP – Pleistocene, when this area was part of the mainland;

6. Geologic Sea Level Rise
6

7. Aboriginal Use of Coast
7
 There is evidence of aboriginal
occupation in the Great Sandy Region
for at least the past 5,500 years.
 Transformed around 3000 BP with
climate induced changes in rainforest
resources
 Demographic and technological
changes occurring approximately 1500
BP may have been triggered by key
areas such as SEQ
 Semi-sedentary aboriginal villages and
huge gatherings of several thousand of
people being supported by migratory
fish runs

8. 1871 Map
8

9. 1876 Harbour
Map
9
 River mouth
appears to be
closer to First
Point

10. 1920s
10

11. 1920 map
11

12. 1930s Sea is Beyond First Point
12

13. 1935 Hastings St
13

14. 1938
14

15. 15
1940s ORIGINAL NOOSA SPIT
Large sand bars shifted up
and down the coast with the
channel.
Main Beach, Noosa Woods
and Noosa Spit in the
1940s show a very different
landscape to that of today.
The promontory of the Spit
was less than half its
current size.

16. Before 1947 Cyclone
16

17. 1947- 48 Cyclone Major Erosion
17

18. 1960s
18

19. 60s early 70s
19

20. 1971 Map
20

21. 1971 at High Tide
21

22. August 1977
22

23. August 1977
23

24. May 1978
24

25. 1979
3 metre sea
cliff
25

26. August 1977
26

27. Coastal Observation
Programme (COPE) 1977-80
27

28. COPE Report
28

29. High Seas in 1988
29

30. February 1989 (after pumping)
30

31. GEOGRAPHY 100
31
Sediment Plume-Burdekin River (CSIRO)
Erosion Alexandra Headlands and
Maroochydore (Sunshine Coast Daily)

32. Estuaries
 Include deltas, tidal marshes and mangrove swamps
 Partially enclosed
 Mixing of fresh and salt water
 Highly productive
 Strongly affected by tides and flows from catchments
MacroalgaeGroundwater
Mangroves
Seagrass
Meadow
Phytoplankton
Terrestrial
Vegetation
Salt marsh
Estuary conceptual model - http://www.ozcoasts.gov.au

33. Typical Beach System
33

34. Processes in the Coastal Zone
© 2012 John Wiley & Sons, Inc.
All rights reserved.
Wind Waves
Friction between air and water
and wind pressure transfers
energy to water – form wave
• Fetch-length of water
exposed to the wind
• Wavelength – distance
between wave crests
• Wave trough - depression
between crests

35. © 2012 John Wiley & Sons, Inc.
All rights reserved.
Waves
• Swash – forward surge of wave
• Backwash – return flow of wave
• Undercurrent (undertow) – force of the backwash carries both
material and people
Processes in the Coastal Zone

36. Coastal Dune Systems
 Dunes are part of the active beach system that helps
protect against storm events
Cross-section of a
sandy beach showing
the significant
difference in the
volume of sediment
eroded in high-
magnitude storms
(1:100 year)
compared to seasonal
erosional events.
http://www.ozcoasts.gov.au

37. Beach Profile Dynamics
37

38. © 2012 John Wiley &
Sons, Inc. All rights
reserved.
Processes in the Coastal Zone
Littoral Drift
• Littoral drift = The transport of sediment parallel with the shoreline by the
combined action of beach drift and longshore current transport Longshore drift
Beach drift – waves reach
beach on an angle the
swash pushes sand up the
beach sand - backwash is
perpendicular to beach
carrying material back out
Long shore Drift - zigzag
path that transports
sediment long distances
along the beach

39. 39
Evidence of
Longshore
Drift
Kirra
1933 and 1973
after the first
groyne was built
Source:
http://www.tweedsandbypa
ss.nsw.gov.au

40. 40

41. Tweed Sand Bypass
41

42. Post Bypass 2004
42

43. Coastal Morphodynamics
43

44. 44

45. Dunes and Beach Erosion
 Clearing and development
on coastal dunes
 Coastal engineering –
groynes, retaining walls
interrupt natural sediment
transport
 Loss dune vegetation
 results in beach erosion
and loss of property
45

46. © 2012 John Wiley &
Sons, Inc. All rights
reserved.
Processes in the Coastal Zone
Wave Refraction
• Headlands - Wave energy concentrated at Headlands where sediment is
eroded
• Wave refraction- Wave fronts slow at headlands and wrap around
headlands
• Pocket beaches – Sediment carried by littoral drift deposits at head of the
bay – crescent shaped beach – long term straightening of the shore

47. © 2012 John Wiley &
Sons, Inc. All rights
reserved.
Human Interactions with Coastal
Processes
Coastal Engineering
• Rip-rap
• Artificial beach nourishment

48. 1960s
48

49. The First Rock Wall
 Following cyclones in 1967–68, panicked
beachfront property owners began dumping
rock in front of their properties to hold back the
sea. With approval from the state
government’s Department of Harbours and
Marine, Noosa Council constructed a boulder
wall that permanently fixed the shape of the
bay. The wall broke up during subsequent
storms, thus requiring further work. 49

50. Noosa Buffer 40m,
North Shore 150m
50

51. Straight Sea Wall 1970
51

52. 3. Hays Island becomes Noosa Sound.
52
In 1972, Noosa Council
approved an application to
develop Hays Island as a
canal estate. It was habitat for
inestimable numbers of crabs,
birds and reptiles, and its
mangroves provided essential
shelter for fish fingerlings.
 The 144-acre development, called Noosa
Sound, stretched from the bridge behind what
is now the Sheraton Resort all the way to
Munna Point.

53. The Sound
Sand was pumped from
the river to raise the
land by one metre and
natural channels were
widened to create
artificial waterways.
53
Following the cyclones of 1974 and 1976,
there was panic about the possible
consequences of a cyclonic event combined
with high tide and river surge. At the time some
of Noosa Sound was in direct line of sight to
the open ocean.

54. 1977 study Flood
Discharge
Volume
54

55. 1978 Estimates
Longshore Transport
55

56. Beach Protection Scheme
1978
56

57. Works in Progress
57

58. Before and After Relocation
58

59. The Spit Extended
In 1977 a scheme for the
“protection” of Hays Island
and “restoration” of Noosa
Beach surfaced, jointly
funded by state and local
governments plus Noosa
Sound’s developers. The
design provided for a
relocation of the river
mouth further northwards
59
The Spit Scheme was
completed in December
1978. Significant erosion
appeared at the southern
end of Noosa Main Beach
only a few months later.

60. New Groyne in 1988
60

61. Softer Beach Nourishment
61

62. 1999 Study
62

63. 63

64. 2001
Study
64

65. Wave Conditions
with and without artificial reef
65

66. Modelled Reef Designs
66

67. Wave Heights
with different
Reef Designs
67

68. New Coastal Management
Option in 2001
68

69. Why wasn’t the Reef Built?
69

70. Sand Pumping
 Trials with a submerged sand-pump began in
December 2004 while plans were developed for
a permanent installation.
70

71. Pumping Statistics
 Approx 1000 cubic metres per day ( 100
truckloads)
 Cost $3.50per cu m ( alternate $15-20 cu
m) (Hastings Street Business levey)
 Aims to achieve a 1:7 gradient to dissipate
wave energy
 On average only need to pump a couple of
times a year , if profile is OK no need to
pump
71

72. 72

73. 73

74. 74

75. Spit ‘Dog’ Beach Erosion and
Management 2010
75

76. Doggy Beach Reclaimed
Even though the hydrologists had not modelled their
proposal beyond the Noosa Spit area, council chose to
proceed with the project at an estimated total cost of
$3.6 million. Due to concerns about stream power
some of the planned submerged geotextile bags were
substituted with rocks.
76

77. Before and After
77

78. Munna Point Erosion 2012
78

79. 79

80. 80

81. NOW & INTO FUTURE
81

82. Ocean acidification
Tracking an Ocean of Carbon FEB 2012 4:02min
Acid Test: The Global Challenge of Ocean Acidification 21:35min
82

83. OCEAN ACIDIFICATION
 the name given to the ongoing decrease in the pH and
increase in acidity of the Earth's oceans, caused by the
uptake of anthropogenic carbon dioxide (CO2) from
the atmosphere.
 About a quarter of the carbon dioxide in the atmosphere
goes into the oceans, where it forms carbonic acid.
 As the amount of carbon has risen in the atmosphere there
has been a corresponding rise of carbon going into the
ocean
 Between 1751 and 1994 surface ocean pH is estimated to
have decreased from approximately 8.25 to
8.14, representing an increase of almost 30% in "acidity"
(H+ ion concentration) in the world's oceans.
 This ongoing acidification of the oceans poses a threat to the
food chains connected with the oceans. 83

84. Coral Reefs
 A rock like accumulation of
carbonates secreted by corals and
algae along marine shorelines
 Largest variety of species of marine
life in a very tiny area
 Produce more living biomass than
any other marine ecosystem
 Remove CO2
 Protect against wave action
 Very important to fisheries
and tourism industries
 Problems: very slow growing
and easily damaged
Great Barrier Reef
GBRMPA

85. Mixing the Metaphor
Captain Nemo Lost Nemo
85

86. Sea Level
Rise
Projections
86
Figure: Estimated
increases in the
frequency of extreme sea
level events (indicated by
the diameters of the
circles), caused by sea
level rises of 10
centimetres (left) and 50
centimetres (right).

87. 1990 - Baseline Summer
Maximum Temperature
2100 – Summer
Maximum Temperature A2

88. CHANGES TO CONDITIONS IN
SEQ
Most Likely Scenario
More frequent and severe droughts.
Increased intensity of storm events
3-5% decrease in rainfall
Increased flooding and erosion

89. Increase Nutrient & Temp
driving Algal Blooms?
89

90. The Story Line
Apologies to Jules Verne
90
YEARS

91. 91