Author(s)

J. C. P. Palma & C. A. O. Costa

Abstract

This paper presents an assessment to the contribution of a telematic Early Warning System (EWS) for reducing the risk of human fatalities due to dam floods. The telematic system consists of a supervisory control post with wireless connection to an array of remote warning units, and involves automation, data communication, acoustic and power supply equipment. The study combines both the modelling of the societal risk associated to flood scenarios and the analysis of functional safety of the telematic system. Both equipment dependability and human factors need to be taken into account in the safety assessment. Besides the calculation of societal risks, the proposed modelling helps by revealing weak points to consider in the design phase, or to review regularly, as well as the relative importance of different actors and resources involved. A case study shows quantitatively the magnitude of the benefits of a hypothetical telematic EWS in a lightly populated dam valley facing high severity and medium severity scenarios, for typical human action parameters. Keywords: dam failure, dam flood warning, early warning system, probability of failure on demand, societal risk reduction. 1 Introduction There is reported evidence that early warning systems (EWSs) can contribute to the reduction of risk in flood prone valleys, downstream of dams, namely in the case of dam rupture, dam overspill, and of unexpected or exceptionally large discharge operations. The conclusion of a real reduction in life loss by timely issued warnings arises from a considerable list of past dam floods in a wide variety of circumstances regarding dam type, number and location of people at

Keywords

dam failure, dam flood warning, early warning system, probability offailure on demand, societal risk reduction