An approach to natural hazard assessments and hazard reduction

Abstract

This thesis endeavours to develop and demonstrate a procedure for the assessment of flood and erosion related natural hazards and prescribing means by which hazard reduction can be achieved. In the context of this study any natural hazard is assumed to fit the definition prescribed in the Resource Management Act 1991 ie it is an adverse effect on humans arising as a consequence of their presence in an area which experiences an atmospheric, earth or water related natural occurrence.

The principal thrust of the Thesis is that a fundamental requirement in assessing a natural hazard is the need to clearly understand the limitations posed by the given natural, setting. In the context of flooding and erosion hazards this approach requires a careful evaluation of the land form and processes (physical setting) and the climatic factors operating in the study area. It follows from this that the community needs to then appreciate the relationship that they have to the natural settings and the constraints on them which are induced by the dynamics of the physical and climatic factors. The challenge is to work within these constraints and in doing so seek to develop sustainable resource management practices designed to avoid or mitigate natural hazard in the chosen setting.

The success of this approach will be largely determined by the skill of the engineer and other managers in accurately portraying to the community the known characteristics of the hazards and the limitations of this knowledge. Equally it is recognised that the community needs to assume some responsibility for ownership of the problem and to actively seek suitable responses. Knowledge, dialogue, responsibility and commitment are key factors in the strategy.

The thesis comprises two parts:

(a) Thesis proper.

(b) Compendium of three natural hazard assessments (case studies) designed to show the methodology in practice.