Developmental activities become the cause of disasters when human beings intensify their activities in disaster-prone areas, increasing their vulnerability. Technological power has given humans large capacity to intervene in nature, leading to increased disaster risks.

One major cause is the colonisation of flood plains and river-beds. The development of large cities and port-towns like Mumbai and Chennai along the coast makes them vulnerable to cyclones, hurricanes and tsunamis. High land values often drive such development in fragile areas.

Deforestation and unscientific land use are significant contributors. Indiscriminate deforestation, unscientific agricultural practices, and disturbances along natural drainage channels accelerate disasters like landslides and floods. Construction activities in fragile areas further intensify these risks.

Some developmental activities directly cause disasters, such as the Bhopal Gas tragedy and Chernobyl nuclear disaster. The release of CFCs, increase in greenhouse gases, and environmental pollution (noise, air, water, soil) are examples of direct human actions leading to disasters.

Previously, people avoided tampering with the delicate balance of ecosystems in hazard-prone areas. However, modern development tends to ignore these natural vulnerabilities, making developmental activities a significant cause of disasters.