In April 2015 the Bureau of Meteorology warned of an East Coast Low that was to affect coastal NS... more In April 2015 the Bureau of Meteorology warned of an East Coast Low that was to affect coastal NSW bringing intense rainfall and likely flooding. This system led to record depths of inundation with devastating effects in Dungog, a small township located at the junction of Myall Creek and the Williams River in the Hunter Valley. This paper offers some early reflections on the tragedy from a flood risk management perspective, aiming to build resilience to future floods in Dungog and beyond.
This report extends, reviews and explains in detail the historical flood series for the Ba River ... more This report extends, reviews and explains in detail the historical flood series for the Ba River at Ba, Fiji, previously described by Yeo et al. (2007). It is the longest quantitative flood series for a river in Fiji, describing 32 floods that have inundated Rarawai Sugar Mill over the 123‐year period from 1892 to 2014, at an average of once every 3.8 years. The accuracy of each flood level is assessed, with 56% of these floods deemed to have a high rating and 34% a medium‐high or medium rating. Flood levels for 12 lesser floods are also estimated. This extended and verified flood series provides the basis for forthcoming statistical analysis.
Flood intelligence is the product of a process of validating and reviewing information about the ... more Flood intelligence is the product of a process of validating and reviewing information about the impacts of flooding on communities. The main report of the SES Flood Intelligence database is the Flood Intelligence Card, which relates flood heights at a stream gauge to consequences within the gauge’s reference area. Good flood intelligence is essential for implementing an effective emergency response including interpreting flood predictions, delivering meaningful warnings and public information, and informing decisions about resourcing and deployment. The SES routinely updates flood intelligence and emergency plans following actual flood events or when synthetic information becomes available in floodplain risk management studies. Following flooding of the Tweed and Richmond River Valleys in January 2008, and the Macdonald, Peel and Namoi River Valleys in November 2008, the SES commissioned flood intelligence reviews. This paper reports some of the key findings which have broad releva...
... The genesis locations are displaced southwestward relative to their El Niño counterparts, wit... more ... The genesis locations are displaced southwestward relative to their El Niño counterparts, with the maximum density centred near 15°S, 170°E. Tropical cyclones that form during La Niña are often steered over Fiji and Tonga with relatively little or no threat to the Samoa region. ...
The relationship between socio-economic factors and vulnerability to natural hazards is well docu... more The relationship between socio-economic factors and vulnerability to natural hazards is well documented in the literature [3]. In addition, it is often hypothesised that communities living in hazard-prone areas are dominated by those of lower socioeconomic status, who are less able to cope with a crisis. This study tests the hypothesis using several flood-prone urban areas of eastern Australia as sample communities. For each urban area, flood-prone and non flood-prone areas were determined using flood risk ratings calculated for individual addresses and derived using Risk Frontiers’ flood inundation risk model, FloodAUS. Socio-economic indicators are available from the Australian Bureau of Statistics (ABS), at the finest resolution of Collection Districts (CD). To determine socio-economic status, four indexes from “Socio-Economic Indexes for Areas 2001” (SEIFA) [2] and two census derived indicators extracted from CDATA 2001 [1] have been used. Six of the seven flood-prone urban area...
Community consultation is an essential component of the floodplain management process. The Floodp... more Community consultation is an essential component of the floodplain management process. The Floodplain Development Manual (p.6) recognises that ‘broad community involvement in the plan preparation, from the beginning, should produce the best prospect for community acceptance of, and commitment to, the resulting management plan’. But often the task of engaging communities proves difficult, and in the worst case, can create a backlash which threatens the integrity of the entire process. Sometimes a genuine commitment to community consultation is lacking. For communities with no recollection of flooding, it is often difficult to generate interest, until houses are designated flood-prone! Tensions in the community and on the Floodplain Management Committee can slow progress. In this paper we report some of the practical tips for successfully engaging the community that we have gleaned from our involvement in over 20 major floodplain risk management studies. Our suggestions cover the full...
The Australian journal of emergency management, 2003
The effect of disclosure of flood-liability on residential property values is of great concern as... more The effect of disclosure of flood-liability on residential property values is of great concern as it creates both positive and negative perceptions. One side the NSW State Emergency Service mandates the publicly dissemination of information relating to floods with the perception that it benefits the property owners, potential purchasers, lending institutions and insurers, however, this kind of disclosure of flood risk information is opposed by many people who perceive that disclosure may reduce the property values.
There are several other examples, however, where flooding was not found to decrease residential p... more There are several other examples, however, where flooding was not found to decrease residential property values. This was the case after the 1986 flood at Des Plaines (Box 2). After flooding at Cambridge in 1974 (Box 5) and at Paeroa and Thames in 1981 (Box 6), ...
This paper assesses the effectiveness of the planning system in relation to flood-prone caravan p... more This paper assesses the effectiveness of the planning system in relation to flood-prone caravan parks in New South Wales. The hazardous location of many caravan parks, allied with the typically high vulnerability to flooding of caravans and their occupants, represents a high risk situation. Reasons for this are explored, including the historical evolution of caravan parks and planning controls, councils’ implementation of those controls, and the role of the Land and Environment Court of NSW. It is argued that flood planning controls have failed to recognise the changing nature of caravan parks. Recommendations to improve flood risk management in caravan parks in NSW include using development controls to manage new developments and to require community awareness measures and emergency planning as a condition for granting approvals to operate parks.
At least 225 people in the Fiji Islands died as a result of the 1931 hurricane and flood, represe... more At least 225 people in the Fiji Islands died as a result of the 1931 hurricane and flood, representing the largest loss of life from a natural disaster in Fiji's recent history. This paper explores the causes of disaster and the potential for recurrence. The disaster occurred because a rare event surprised hundreds of people-especially recently settled Indian farmers-occupying highly exposed floodplains in northwest Viti Levu island. The likelihood of a flood disaster of such proportions occurring today has been diminished by changed settlement patterns and building materials; however, a trend towards re-occupancy of floodplains, sometimes in fragile dwellings, is exposing new generations to flood risks. The contribution of this paper to the global hazards literature is set out in three sections: the ethnicity, gender and age of flood fatalities; the naturalness of disasters; and the merit of choice and constraint as explanations for patterns of vulnerability.
A survey of 71 caravan parks in coastal NSW indicates a high exposure to flooding. Most parks in ... more A survey of 71 caravan parks in coastal NSW indicates a high exposure to flooding. Most parks in NSW are flood-prone. A growing number of long-term residents in the 1980s, and essentially immovable manufactured homes in the 1990s, significantly increased flood risk. However, many parks are ill-equipped to deal with flooding: a high turnover of park managers means that most
The diverse causes and styles, the frequency and the losses arising from five Australian floods i... more The diverse causes and styles, the frequency and the losses arising from five Australian floods in 1998 are reviewed in this paper. Though mostly rare, the floods were not as unprecedented as commonly supposed. Damages to agriculture and infrastructure were significant, and probably over 10,000 houses experienced over-floor inundation. Key lessons include: the need for detailed damage assessments as a basis for damage reduction, the need to maximise safety and minimise property exposure at caravan parks, and the need for floodplain management strategies that better address both existing and future risk. A greater recognition of the distinctive nature of each flood event is required for the improvement of official and unofficial flood warning systems. Educators need to address the dynamic nature of flood awareness, as it declines over time, and as it varies from one individual to the next. Insurers need to adopt incentives for risk-reducing behaviour, so that efforts to mitigate damages are encouraged, not undermined.
The economic impact of natural disasters on developing economies can be severe with the recovery ... more The economic impact of natural disasters on developing economies can be severe with the recovery diverting scarce funds that might otherwise be targeted at development projects and stimulating the need for international aid. In view of the likely sensitivity of low-lying Pacific Islands to anticipated changes in climate, a 122-year record of major flooding depths at the Rarawai Sugar Mill on the Ba River in the northwest of the Fijian Island of Viti Levu is analysed. Reconstructed largely from archived correspondence of the Colonial Sugar Refining Company, the time series comprises simple measurements of height above the Mill floor. It exhibits no statistically significant trends in either frequency or flood heights, once the latter have been adjusted for average relative sea-level rise. This is despite persistent warming of air temperatures as characterized in other studies. There is a strong dependence of frequency (but not magnitude) upon El Niño-Southern Oscillation (ENSO) phase, with many more floods in La Niña phases. The analysis of this long-term data series illustrates the difficulty of detecting a global climate change signal from hazard data, even given a consistent measurement methodology (cf HURDAT2 record of North Atlantic hurricanes) and warns of the strong dependence of any statistical significance upon choices of start and end dates of the analysis.
In April 2015 the Bureau of Meteorology warned of an East Coast Low that was to affect coastal NS... more In April 2015 the Bureau of Meteorology warned of an East Coast Low that was to affect coastal NSW bringing intense rainfall and likely flooding. This system led to record depths of inundation with devastating effects in Dungog, a small township located at the junction of Myall Creek and the Williams River in the Hunter Valley. This paper offers some early reflections on the tragedy from a flood risk management perspective, aiming to build resilience to future floods in Dungog and beyond.
This report extends, reviews and explains in detail the historical flood series for the Ba River ... more This report extends, reviews and explains in detail the historical flood series for the Ba River at Ba, Fiji, previously described by Yeo et al. (2007). It is the longest quantitative flood series for a river in Fiji, describing 32 floods that have inundated Rarawai Sugar Mill over the 123‐year period from 1892 to 2014, at an average of once every 3.8 years. The accuracy of each flood level is assessed, with 56% of these floods deemed to have a high rating and 34% a medium‐high or medium rating. Flood levels for 12 lesser floods are also estimated. This extended and verified flood series provides the basis for forthcoming statistical analysis.
Flood intelligence is the product of a process of validating and reviewing information about the ... more Flood intelligence is the product of a process of validating and reviewing information about the impacts of flooding on communities. The main report of the SES Flood Intelligence database is the Flood Intelligence Card, which relates flood heights at a stream gauge to consequences within the gauge’s reference area. Good flood intelligence is essential for implementing an effective emergency response including interpreting flood predictions, delivering meaningful warnings and public information, and informing decisions about resourcing and deployment. The SES routinely updates flood intelligence and emergency plans following actual flood events or when synthetic information becomes available in floodplain risk management studies. Following flooding of the Tweed and Richmond River Valleys in January 2008, and the Macdonald, Peel and Namoi River Valleys in November 2008, the SES commissioned flood intelligence reviews. This paper reports some of the key findings which have broad releva...
... The genesis locations are displaced southwestward relative to their El Niño counterparts, wit... more ... The genesis locations are displaced southwestward relative to their El Niño counterparts, with the maximum density centred near 15°S, 170°E. Tropical cyclones that form during La Niña are often steered over Fiji and Tonga with relatively little or no threat to the Samoa region. ...
The relationship between socio-economic factors and vulnerability to natural hazards is well docu... more The relationship between socio-economic factors and vulnerability to natural hazards is well documented in the literature [3]. In addition, it is often hypothesised that communities living in hazard-prone areas are dominated by those of lower socioeconomic status, who are less able to cope with a crisis. This study tests the hypothesis using several flood-prone urban areas of eastern Australia as sample communities. For each urban area, flood-prone and non flood-prone areas were determined using flood risk ratings calculated for individual addresses and derived using Risk Frontiers’ flood inundation risk model, FloodAUS. Socio-economic indicators are available from the Australian Bureau of Statistics (ABS), at the finest resolution of Collection Districts (CD). To determine socio-economic status, four indexes from “Socio-Economic Indexes for Areas 2001” (SEIFA) [2] and two census derived indicators extracted from CDATA 2001 [1] have been used. Six of the seven flood-prone urban area...
Community consultation is an essential component of the floodplain management process. The Floodp... more Community consultation is an essential component of the floodplain management process. The Floodplain Development Manual (p.6) recognises that ‘broad community involvement in the plan preparation, from the beginning, should produce the best prospect for community acceptance of, and commitment to, the resulting management plan’. But often the task of engaging communities proves difficult, and in the worst case, can create a backlash which threatens the integrity of the entire process. Sometimes a genuine commitment to community consultation is lacking. For communities with no recollection of flooding, it is often difficult to generate interest, until houses are designated flood-prone! Tensions in the community and on the Floodplain Management Committee can slow progress. In this paper we report some of the practical tips for successfully engaging the community that we have gleaned from our involvement in over 20 major floodplain risk management studies. Our suggestions cover the full...
The Australian journal of emergency management, 2003
The effect of disclosure of flood-liability on residential property values is of great concern as... more The effect of disclosure of flood-liability on residential property values is of great concern as it creates both positive and negative perceptions. One side the NSW State Emergency Service mandates the publicly dissemination of information relating to floods with the perception that it benefits the property owners, potential purchasers, lending institutions and insurers, however, this kind of disclosure of flood risk information is opposed by many people who perceive that disclosure may reduce the property values.
There are several other examples, however, where flooding was not found to decrease residential p... more There are several other examples, however, where flooding was not found to decrease residential property values. This was the case after the 1986 flood at Des Plaines (Box 2). After flooding at Cambridge in 1974 (Box 5) and at Paeroa and Thames in 1981 (Box 6), ...
This paper assesses the effectiveness of the planning system in relation to flood-prone caravan p... more This paper assesses the effectiveness of the planning system in relation to flood-prone caravan parks in New South Wales. The hazardous location of many caravan parks, allied with the typically high vulnerability to flooding of caravans and their occupants, represents a high risk situation. Reasons for this are explored, including the historical evolution of caravan parks and planning controls, councils’ implementation of those controls, and the role of the Land and Environment Court of NSW. It is argued that flood planning controls have failed to recognise the changing nature of caravan parks. Recommendations to improve flood risk management in caravan parks in NSW include using development controls to manage new developments and to require community awareness measures and emergency planning as a condition for granting approvals to operate parks.
At least 225 people in the Fiji Islands died as a result of the 1931 hurricane and flood, represe... more At least 225 people in the Fiji Islands died as a result of the 1931 hurricane and flood, representing the largest loss of life from a natural disaster in Fiji's recent history. This paper explores the causes of disaster and the potential for recurrence. The disaster occurred because a rare event surprised hundreds of people-especially recently settled Indian farmers-occupying highly exposed floodplains in northwest Viti Levu island. The likelihood of a flood disaster of such proportions occurring today has been diminished by changed settlement patterns and building materials; however, a trend towards re-occupancy of floodplains, sometimes in fragile dwellings, is exposing new generations to flood risks. The contribution of this paper to the global hazards literature is set out in three sections: the ethnicity, gender and age of flood fatalities; the naturalness of disasters; and the merit of choice and constraint as explanations for patterns of vulnerability.
A survey of 71 caravan parks in coastal NSW indicates a high exposure to flooding. Most parks in ... more A survey of 71 caravan parks in coastal NSW indicates a high exposure to flooding. Most parks in NSW are flood-prone. A growing number of long-term residents in the 1980s, and essentially immovable manufactured homes in the 1990s, significantly increased flood risk. However, many parks are ill-equipped to deal with flooding: a high turnover of park managers means that most
The diverse causes and styles, the frequency and the losses arising from five Australian floods i... more The diverse causes and styles, the frequency and the losses arising from five Australian floods in 1998 are reviewed in this paper. Though mostly rare, the floods were not as unprecedented as commonly supposed. Damages to agriculture and infrastructure were significant, and probably over 10,000 houses experienced over-floor inundation. Key lessons include: the need for detailed damage assessments as a basis for damage reduction, the need to maximise safety and minimise property exposure at caravan parks, and the need for floodplain management strategies that better address both existing and future risk. A greater recognition of the distinctive nature of each flood event is required for the improvement of official and unofficial flood warning systems. Educators need to address the dynamic nature of flood awareness, as it declines over time, and as it varies from one individual to the next. Insurers need to adopt incentives for risk-reducing behaviour, so that efforts to mitigate damages are encouraged, not undermined.
The economic impact of natural disasters on developing economies can be severe with the recovery ... more The economic impact of natural disasters on developing economies can be severe with the recovery diverting scarce funds that might otherwise be targeted at development projects and stimulating the need for international aid. In view of the likely sensitivity of low-lying Pacific Islands to anticipated changes in climate, a 122-year record of major flooding depths at the Rarawai Sugar Mill on the Ba River in the northwest of the Fijian Island of Viti Levu is analysed. Reconstructed largely from archived correspondence of the Colonial Sugar Refining Company, the time series comprises simple measurements of height above the Mill floor. It exhibits no statistically significant trends in either frequency or flood heights, once the latter have been adjusted for average relative sea-level rise. This is despite persistent warming of air temperatures as characterized in other studies. There is a strong dependence of frequency (but not magnitude) upon El Niño-Southern Oscillation (ENSO) phase, with many more floods in La Niña phases. The analysis of this long-term data series illustrates the difficulty of detecting a global climate change signal from hazard data, even given a consistent measurement methodology (cf HURDAT2 record of North Atlantic hurricanes) and warns of the strong dependence of any statistical significance upon choices of start and end dates of the analysis.
Serious flooding of Sussex Inlet and Lake Conjola in August 2015 provided the opportunity to asse... more Serious flooding of Sussex Inlet and Lake Conjola in August 2015 provided the opportunity to assess the effectiveness of flood emergency management plans (FEMPs) at flooded caravan parks. A survey of 16 caravan parks found that FEMPs were universally not enacted. Some park managers judged that the risk was low due to the low occupancy rates, and so did not need to enact their FEMPs. Others were not even aware of a FEMP. Various strategies to improve the effectiveness of FEMPs are proposed, including making the template more accessible by focussing on the key actions required, making the template more flexible, and mandating FEMP reviews as a condition of granting annual approvals to operate. In addition, and perhaps of most importance, greater investment in social and experiential learning approaches is required, to promote park managers' appreciation of changing flood risks and to facilitate sharing between park managers of innovative approaches to managing risk.
This paper provides a review of the international and local literature assessing the impact of fl... more This paper provides a review of the international and local literature assessing the impact of flood risk information on residential property values. We extend the findings of a previous review conducted over a decade ago when flood risk disclosure regimes in Australia were quite different. After a brief discussion of methods typically used for assessing the value of flood risk and their strengths and weaknesses, we examine three questions. On the question of the effect of being located in a floodplain there exists considerable heterogeneity in the empirical results, though flood-prone land is often discounted. The degree of discounting may be associated with the degree of risk, and the discount can often be traced back to a flood event. But sometimes positive attributes of a waterfront or coastal location outweigh any discount. On the question of the effect of an actual flood event on property values, the characteristic effect is discounting in impacted areas, exacerbated by multiple floods in a short time-span and even extending to areas not flooded. Property values typically recover in time. On the question of the effect of floodplain designation and its disclosure, we find it can initiate or increase discounting, or have no effect, or even reduce discounting. This relates to the different forms of disclosure, particularly whether it is mandatory and at what point in the transaction process the flood risk is revealed. We conclude with implications for flood risk managers in Australia.
The April 2015 flood tragedy at Dungog represents a microcosm of some of the ongoing floodplain r... more The April 2015 flood tragedy at Dungog represents a microcosm of some of the ongoing floodplain risk management (FRM) challenges confronting Australia today. This paper presents a preliminary assessment of the flooding, its impacts and implications for floodplain managers. It was evidently an extreme flood, without parallel in Dungog’s recorded history. The drowning of three older people in their dwellings is, nevertheless, unacceptable. Land use planning needs to take a greater share of the FRM load, including keeping seniors’ accommodation out of floodplains and ensuring that standard residential accommodation adequately manages risk-to-life in rarer events. The flood taught that whether because of the scale and speed of the event, split resources, declining volunteerism, leadership turnover, local road closures and communications difficulties, the emergency services cannot be guaranteed to rescue everyone in need of rescue. Many people based their perception of risk on their previous experience of flooding in 2007, which was metres lower. More attention is needed for residual risks (above the 1% AEP flood), requiring the application of controlled imaginations to assess and manage to an acceptable level what may appear to be the most unlikely of risk scenarios.
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Papers by Stephen Yeo