Developing an early warning system to strengthen disaster risk resilience: experiences from flood-prone areas of KwaZulu-Natal province.

Abstract

Globally, the frequency and intensity of extreme weather events including flash floods, rising sea levels, and storms is increasing. Poorly planned informal settlements have become more vulnerable. In most regions, infrastructure to cope and protect the vulnerable from such impacts is inadequate. This article aimed to elucidate the main issues faced by South Africa in terms of flood forecasting as well as present an innovative method to assess exposure to floods. A qualitative approach was utilized to gather data during interviews with community leaders and residents of Quarry Road informal settlement. A flood hazard index was developed in a GIS environment. Distance from rivers was calculated, and rainfall intensity and water table level were estimated from metrological measurements, groundwater logging data, and SAR data. A spatial analysis evaluated each grid-point on every parameter and according to the local conditions and each point was assigned values on a scale between 2 and 10. The findings revealed areas most prone to floods in the settlement and the need for a comprehensive post-flood damage database meant for validation purposes and calibrating future prediction models.