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Severe unprecedented flooding of unprepared and inexperienced communities adversely affects community health, but the effect of severe flooding on well‐prepared and experienced communities is less certain. An answer was sought for the New South Wales coastal town of Lismore. Parts are flooded every year with the last major flood occurring in 1974. Hospital admission and death certificates were analysed for the years before and after that flood. Using this data and information from an earlier survey two types of analysis were undertaken: a comparison of mortality and hospital admissions before and after the flood; and a comparison of health effects between different levels of flooding, including residents whose properties were located outside the flood plain. Although the flood did not appear to increase the number of hospital admissions or deaths, the ratio of male to female admissions showed a significant change. For those severely flooded, male admissions doubled while female admissions halved. Analysis of the data in relation to flood risk showed that for both pre‐and post‐flood periods hospital admissions were closely related to the degree of flood risk. Those whose dwellings were subject to a metre or more offloodwater over floor level are twice as likely to be admitted to hospital as residents of the flood free areas.

A traversing microerosion meter (MEM) was used to measure the rates of surface weathering of limestones in southeastern Australia. There were two groups of MEM sites installed in 1978/9. The aim of the experimental design for the first type, the 13 sites at Cooleman Plain and Yarrangobilly Caves, was to obtain erosion rates for limestones of similar lithology exposed under comparable climate conditions. The sites were positioned to measure erosion over a range of microsolutional forms and with exposure to differing forms of erosion, i.e. subaerial, subsoil and instream. The second set, at Ginninderra close to Canberra, consists of nine limestone slabs of differing lithology, collected from different locations but exposed under identical climatic conditions. The number of individual measurement points at each MEM site varied from 24 to 68.There were major differences in erosion rates between subaerial bedrock and instream sites at Yarrangobilly and Cooleman Plain, but no evidence of differential erosion across the micro-forms. There were differences in the weathering rate for bedrock sites, due to climatic differences, and between the limestone lithologies exposed at Ginninderra. The average rate of erosion for the subaerial bedrock sites at Cooleman Plain and Yarrangobilly over the 13 years was 0.01 3 mm a-' and at Ginninderra 0.006 mm a-' . At some of the sites microflora (lichens and mosses) caused problems for field measurement.The weathering processes that contribute to the surface lowering are discussed in the accompanying paper by Moses et al.