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NSW Maritime Panel and PIANC Australia
Practical Adaption to Climate Change on NSW Coasts
Port and Harbour Considerations
Greg Britton, WorleyParsons
Monday 24th August 2009
9/09/2009
Focus of talk
� Adaptation, not mitigation� Not considering issues
such as carbon footprints and trading, sustainability of material inputs, energy use, etc
� Ports are considering these issues, eg Sydney Ports Green Port Guidelines
9/09/2009
Why are ports and harbours vulnerable to climate change?
� potential effects of climate change• sea level rise• increased rainfall intensity /
frequency• changes to ocean storm
intensity (increased wave heights)
• increased wind loads• ocean currents• acidification
� features of ports and harbours
Source: DECC (2009)Draft Technical Note: Scientific basis of the 2009 sea level rise
benchmark
Features of ports and harbours:
� location: connected to the sea (sea level rise)
• embayments : natural, man-made (relative protection)
• in the open sea (storminess)
• within river estuaries (rainfall / runoff, sedimentation)
Features of ports and harbours:
� channels, berthing basins, swinging basins• declared depth• water surface level variation• bed level variation
� land / water interface infrastructure: wharves, jetties, dolphins• functionality, eg deck level• uptime• susceptibility for damage• associated equipment, eg
shiploaders
Features of ports and harbours:
� protective structures; breakwaters, seawalls, revetments• depth limited waves, stability• overtopping performance• degree of exposure
� land-based infrastructure: hardstand, stockpile areas, buildings, roads, stormwater• flooding• drainage• water quality
Features of ports and harbours:
� planning life
• infrastructure
• equipment
� significance to the Australian economy
• ports act as the gateway for trade into and out of Australia andobviously have vast economic significance
• 83% of all our exports by value (about $100 billion)
• 70% of all our imports by value (about $80 billion)
Factors affecting climate change adaption methodologies for ports and harbours:
� uncertainty in the magnitude of climate change effects
� high natural variability in existing physical processes
� significant embedded infrastructure
� life of infrastructure, including variability of components
� infrastructure must be functional now as well as over its future life
Ultimately a flexible approach required, risk based assessment, often a low investment outcome adopted
Existing Guidelines:
� AS 4997-2005 Guidelines for Design of Maritime Structures. Focus on sea level rise.• amount of SLR depends on design life• does not necessarily mean raised decks• examples of allowance for SLR: raise heights of restraining
piles on floating structures at a later time, or install substructure of adequate strength to permit future topping slabs etc.
� Guidelines for Responding to the Effects of Climate Change in Coastal and Ocean Engineering (Engineers Australia, 2004 Update): retreat, accommodate or protect.
� International practice
Some examples of adaptive methodologies:
� Port of Newcastle maintenance dredging of shipping channels
� Sydney Harbour Ferry Wharves Upgrade
Port of Newcastle maintenance dredging:
� located on a major river estuary subject to flooding (Hunter River)
� ongoing requirement for maintenance dredging, commenced 1859, greater than 130 Mm3 to date, typically 200,000 to 300,000 m3 per annum
� two sources of sedimentation
• fluvial inputs
• coastal processes
Adaptive approach:
� retain NPC owned dredger
� seek permit for high range maintenance dredging quantity
� seek alternative disposal areas
� undertake regular hydrographic surveys including surveys beyond channel limits
� supplement NPC dredger with contract dredger as required
Sydney Harbour Ferry Wharves Upgrade:
� NSW Maritime has upgrade strategy for 46 ferry wharves over next 15 years
� WorleyParsons has undertaken review of standard concept wharf designs, addressing following issues:
• general design criteria, eg design life, sea level rise
• site specific environmental design criteria
• operational constraints, including disabled access
• value engineering review, including public safety
Sydney Harbour Ferry Wharves Upgrade:
Important design details
� design life 50 years
� fixed landing level
� hinged access ramp slope, length, width
� satisfying disability guidelines for accessible public transport
Adaptive approach
� fixed landing level 2.9m CD, longer ramps
Conclusion:
� ports are vital to the economy
� restricted attention has been given to date to impacts of climate change on port infrastructure, port operations and the environment
� attention is likely to have to escalate
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