The Cressbrook Creek alluvial aquifer system, Southeast Queensland : hydrochemistry and isotopes to determine hydrological processes and response to floods

This study developed an understanding of hydrological processes within the Cressbrook Creek catchment of the upper Brisbane River, in particular for the alluvial aquifers. Those aquifers within the lower catchment are used for intensive irrigation, and have been impacted by long-term drought followed by flooding. The study utilised water chemistry, isotopic characters and hydraulic measurements to determine factors such as recharge, links between creeks and groundwater, and variations in water quality. The catchment-wide study will enable improved management of the local water resources.

Exploring association between perceived importance of travel/traffic information and travel behaviour in natural disasters : a case study of the 2011 Brisbane floods

A sound understanding of travellers’ behavioural changes and adaptation when facing a natural disaster is a key factor in efficiently and effectively managing transport networks at such times. This study specifically investigates the importance of travel/traffic information and its impact on travel behaviour during natural disasters. Using the 2011 Brisbane flood as a case study, survey respondents’ perceptions of the importance of travel/traffic information before, during, and after the flood were modelled using random-effects ordered logit. A hysteresis phenomenon was observed: respondents’ perceptions of the importance of travel/traffic information increased during the flood, and although its perceived importance decreased after the flood, it did not return to the pre-flood level. Results also reveal that socio-demographic features (such as gender and age) have a significant impact on respondents’ perceptions of the importance of travel/traffic information. The roles of travel time and safety in a respondent’s trip planning are also significantly correlated to their perception of the importance of this information. The analysis further shows that during the flood, respondents generally thought that travel/traffic information was important, and adjusted their travel plans according to information received. When controlling for other factors, the estimated odds of changing routes and cancelling trips for a respondent who thought that travel/traffic information was important, are respectively about three times and seven times the estimated odds for a respondent who thought that travel/traffic information was not important. In contrast, after the flood, the influence of travel/traffic information on respondents’ travel behaviour diminishes. Finally, the analysis shows no evidence of the influence of travel/traffic information’s on respondents’ travel mode; this indicates that inducing travel mode change is a challenging task.

Factors influencing vulnerability and positive post-disaster response following the Mackay 2008 and Brisbane 2011 floods

This project investigated which aspects of being flooded most affected mental health outcomes. It found that stress in the aftermath of the flood, during the clean-up and rebuilding phase, including stress due to difficulties with insurance companies, was a previously overlooked risk factor, and social support and sense of belonging were the strongest protective factors. Implications for community recovery following disasters include providing effective targeting of support services throughout the lengthy rebuilding phase; the need to co-ordinate tradespeople; and training for insurance company staff aimed at minimising the incidence of insurance company staff inadvertently adding to disaster victims' stress.

Floods and property values: A hedonic property and efficiency analysis

This study investigates the impact floods on property values using the hedonic property price approach and other relevant econometric techniques. The main objectives of this research are to investigate (1) the impact of the release of flood-risk information and the actual floods on property values (2) the temporal behaviour of negative impacts (3) the property submarket behaviour (4) the behaviour of flood affected vs flood non-affected areas and (5) the property market efficiency. The thesis expanded on the existing literature on natural disasters by applying a range of econometric techniques. Findings of this research are useful for policy decision-making which is aimed at minimizing the negative impacts of natural hazards on property markets. The thesis findings also provide a better framework for decision-making in the property insurance market. The methodological improvements that are made in the thesis will be invaluable for analysing the impacts of natural hazards elsewhere.

Impact of wildfires and floods on property values: A before and after analysis

One of the most evident casualties of a natural disaster is the property market. The private and social costs from such events run into millions of dollars. In this paper, we use a unique dataset to examine the impact on residential house prices affected by natural disasters using a hedonic property (HP) values approach. For this purpose, we use data before and after a wildfire and floods from Rockhampton in central Queensland, Australia. The data is unique because one suburb was affected by wildfires and another was affected by floods. For the analysis, three suburbs namely Frenchville, Park Avenue and Norman Gardens are used. Frenchville was significantly affected by wildfires in the latter part of 2009 and to a lesser extent in 2012, while Park Avenue was affected by floods at the end of 2010, January 2011–2013. Norman Gardens, which was relatively unaffected, is used as a control site. This enables us to examine the before and after effects on property values in the three suburbs. The results confirm that soon after a natural disaster property prices in affected areas decrease even though the large majority of individual houses remain unaffected. Furthermore, the results indicate that the largely unaffected suburb may gain immediately after a natural disaster but this gain may disappear if natural disasters continue to occur in the area/region due to the stigma created. The results have several important policy decision and welfare implications which are briefly discussed in the paper.

Flood risk information, actual floods and property values: A quasi-experimental analysis

Hedonic property price analysis tells us that property prices can be affected by natural hazards such as floods. This paper examines the impact of flood-related variables (among other factors) on property values, and examines the effect of the release of flood risk map information on property values by comparing the impact with the effect of an actual flood incidence. An examination of the temporal variation of flood impacts on property values is also made. The study is the first of its kind where the impact of the release of flood risk map information to the public is compared with an actual flood incident. In this study, we adopt a spatial quasi-experimental analysis using the release of flood risk maps by Brisbane City Council in Queensland, Australia, in 2009 and the actual floods of 2011. The results suggest that property buyers are more responsive to the actual incidence of floods than to the disclosure of information to the public on the risk of floods.

Urban Floods: Case Study of Bangalore

Bangalore is one of the fastest growing cities in India and is branded as ‘Silicon Valley of India’ for heralding and spearheading the growth of Information Technology (IT) based industries in the country. With the advent and growth of IT industry, as well as numerous industries in other sectors and the onset of economic liberalisation since the early 1990s, Bangalore has taken lead in service-based industries fuelling substantial growth of the city both economically and spatially. Bangalore has become a cosmopolitan city attracting people and business alike, within and across nations. This profile notes the urban setting and provides an overview of the urban fabric, while discussing various prospects related to infrastructure and governance (Sudhira, et al. 2007).

Bivariate frequency analysis of floods using a diffusion based kernel density estimator

Recent focus of flood frequency analysis (FFA) studies has been on development of methods to model joint distributions of variables such as peak flow, volume, and duration that characterize a flood event, as comprehensive knowledge of flood event is often necessary in hydrological applications. Diffusion process based adaptive kernel (D-kernel) is suggested in this paper for this purpose. It is data driven, flexible and unlike most kernel density estimators, always yields a bona fide probability density function. It overcomes shortcomings associated with the use of conventional kernel density estimators in FFA, such as boundary leakage problem and normal reference rule. The potential of the D-kernel is demonstrated by application to synthetic samples of various sizes drawn from known unimodal and bimodal populations, and five typical peak flow records from different parts of the world. It is shown to be effective when compared to conventional Gaussian kernel and the best of seven commonly used copulas (Gumbel-Hougaard, Frank, Clayton, Joe, Normal, Plackett, and Student's T) in estimating joint distribution of peak flow characteristics and extrapolating beyond historical maxima. Selection of optimum number of bins is found to be critical in modeling with D-kernel.

The floods of the Lake District - Part I

This report summarises the annual rainfall of the River Derwent catchment area and examines the floods of 1931 and 1932. The author uses data from the Meteorological Office to examine if the floods were extraordinary and takes into account local lakes in reducing the magnitude of the flood. Areas that are presented in more detail are Bassenthwaite Lake, Thirlmere, Cockermouth, Keswick, Newlands and Coledale Beck. (PDF contains 38 pages)

Anomalous atmospheric circulation and large winter floods in six subregions of the southwestern United States

EXTRACT (SEE PDF FOR FULL ABSTRACT): We examined atmospheric circulation conditions conducive to occurrence of winter floods that exceed the 10-year peak discharge on rivers in six hydroclimatic subregions in Arizona, southern Utah, Nevada, and California. ... This relationship between flooding and broad-scale atmospheric patterns in the modern record will aid in paleoclimatic interpretations of paleoflood records over the last few thousand years.

The top ten California floods of the 20th century

The purpose of this paper is to summarize the biggest northern California floods of the 20th century. Flooding in California can occur from different causes. At least three types of floods occur: 1. Winter general floods, which cover a large area. 2. Spring and early summer snowmelt floods unique to the higher-elevation central and southern Sierra Nevada, which occur about once in 10 years on the average. 3. Local floods from strong thunderstorms, with intense rain over a relatively small area. These originate in moist tropical or subtropical air and include the flash floods of the desert and other areas of southern California when remnants of eastern Pacific hurricanes get carried into the state.