IMPACTS OF TROPICAL CYCLONES ON COMMUNITIES

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1 IMPACTS OF TROPICAL CYCLONES ON COMMUNITIES I M P L I C AT I O N S F O R C O M M U N I T Y H E A LT H Geoff Boughton and Debbie Falck TimberED Services

2 OUTLINE OF PRESENTATION Tropical cyclones Wind actions on buildings Damage Risk Role of buildings Implications for community health

3 TROPICAL CYCLONE VANCE Exmouth, March, 1999 Category 5 Largest recorded wind speed over land in Australia km/hr 87% design ultimate wind speed Severe structural damage to older houses Water ingress to newer houses

4 TROPICAL CYCLONE GEORGE March, 2007 Category 3 in Port Hedland (Region D) Peak gust up to 205 kph 65% of design wind speed Structural damage to 2% buildings mainly older houses Rail Camp 1 (Region B) Peak gust around 180 kph 88% of design wind speed 2 deaths

5 TROPICAL CYCLONE OLWYN Exmouth, March, 2015 Category 3 Peak gust 185 kph 67% design wind speed Little structural damage Significant damage from wind-driven rain

6 TROPICAL CYCLONE WINDS 267 km/hr

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8 WATER EVERYWHERE Storm Surge low pressure lifts water surface Flooding watercourses swollen debris can block drainage Wind driven rain flows up walls, windows enters buildings through doors and windows, flashings

9 WIND ACTIONS ON BUILDINGS

10 WIND CAN MAKE ROOFS FLY

11 PRESSURE ON WINDWARD WALLS Wind direction Pressure

12 SUCTION ON ROOF, SIDE AND LEEWARD WALLS Suction on roof surfaces Wind direction

13 INTERNAL PRESSURES Windward wall PRESSURE inside Side wall Suction inside Leeward wall Suction inside Roof space PRESSURE in roof

14 STRUCTURAL DAMAGE Roofs Walls Foundations

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16 FAILURE OF WINDOWS AND DOORS Glass breakage due to wind Failure of frames Debris pushed screens onto glass

17 NON-STRUCTURAL DAMAGE

18 WATER THROUGH WINDOWS

19 DAMAGE TO LININGS AND CONTENTS

20 VULNERABLE MATERIALS Ceilings plasterboard Wall linings plasterboard Floor coverings carpet, timber overlay

21 MINOR DAMAGE, DISASTER OR DEVASTATION? Community function significantly disrupted Deaths Injuries Homelessness Infrastructure Isolation Economic loss

22 AIM TO MINIMISE RISK TO COMMUNITY RISK EVENT ASSETS vulnerability PROTECTION

23 ROLE OF BUILDINGS IN RISK MITIGATION Prevention buildings built to withstand wind Preparedness essential shelter during and after the event Response medical, organisational, accommodation functions Recovery rebuilding community functions

24 BUILDING PERFORMANCE Bad building performance can turn an EVENT into a DISASTER Good building performance can make a potential disaster not even newsworthy!

25 DEMONSTRATING PERFORMANCE Design wind loads from AS or AS 4055 Capacity of connections and members from Framing Codes Material codes - Timber/Steel/Concrete/Masonry Over-loading and/or Under-performance DAMAGE

26 Improving Building Performance prior to event Resilience Redundancy Ductility Regular inspection and maintenance Supervision and inspection during construction Special attention to buildings with post-disaster function Details, details, details

27 Improving Building Performance after the event Supervision and inspection during reconstruction Retrofitting resolve existing problems Details, details, details

28 RETROFITTING Now that we know of some systems with problems implications for undamaged buildings? implications for similar buildings in cyclone areas?

29 IMPLICATIONS FOR COMMUNITY HEALTH Perceived safety of buildings Water penetration Ponded water Asbestos Loss of power and water Green waste and building waste Roads and transport Storm surge Evacuation Mental health/well-being issues Pets and animals

30 Perceived safety of buildings Confidence in the buildings previous performance preparation strong compartments Cyclone shelters Reinforce safety procedures mopping up during the event stupidity vs heroism Risk of death or injury

31 DEBRIS

32 WATER PENETRATION Water flows upward design ineffective gutters, flashings, windows into roof and wall cavities Plasterboard internal linings bacteria and fungi health risk less effective as structural bracing element Corrosion of connectors and metal framing elements Fungal growth

33 Ponded water Ideal breeding ground for disease-carrying insects Ineffective drainage Disease Blocked water course

34 ASBESTOS Risk Costs Licenced contractor

35 Loss of power Refrigeration Medical services Water and sewerage Computer systems Communication systems Commercial activity Industry Disease, death, injury

36 STORM SURGE Rise in sea level Flooding Collapse of structures Corrosion Poisons the land Erosion Drowning, injury

37 EVACUATION Before or after event? Safety Reduce demand on damaged infrastructure and depleted resources Well planned and executed Anger, stress, trauma Keep families together Secure premises and possessions Drying out belongings

38 WELL-BEING AND MENTAL HEALTH ISSUES Recovery Insurance Financial assistance WANDRRA Inflation Time Grief, loss Anger Frustration

39 IMPLEMENT RECOVERY MANAGEMENT STRATEGIES QUICKLY AND EFFECTIVELY Evacuation procedures Inform and involve the community Vector control Expert assistance Counselling Control of looting Avoid complacency for future events Effective education preparedness, retrofitting

40 FINAL COMMENTS Life and expectations are changing Damage patterns have changed Higher reliance on infrastructure Perceptions of safety Cyclone shelters Efficient and effective recovery People learn from own experiences but not those of others Education the key

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