This study evaluated the association between flood-related variables and morbidity. Since Typhoon Morakot affected entire Taiwan, the Morakot flood data and the geographically-coded morbidity data were analyzed together to examine the effect of flood and flood-control engineering on morbidity. It was concluded that the Morakot flood was associated with increased eczema morbidity. River landscape construction was associated with a decrease in adult eczema morbidity cases after the Morakot flood. However, depressive disorder, anxiety disorder, pneumonia, septicemia, cellulitis and abscess, and atopic dermatitis were not associated with the Morakot flood and river landscape construction.