The increasing number of dams built in the last century has underlined the necessity of these constructions to the all-round development of a country. The advent of rock mechanics, engineering geology and a better understanding of materials have made it possible to construct higher and larger dams and to tackle more difficult sites. The assumptions and risks used in the theory of dam design include such unpredictable events as earthquakes, floods, and geological faults or soft seams, which may be either underestimated or completely missed during initial exploration. Incidents relating to dams are manageable at an early stage, whereas accidents, which are largely unforeseen, result in unexpected behaviour of dams and in catastrophic failures. Investigations conducted to determine the cause of a failure may not reveal the true sequence of events, while expert analyses are often controversial. From the dams that do not fail, of course, we learn nothing. Systematically monitoring the dam’s behaviour from the potential risk stage to the accident event, would allow a hazard-management programme to be implemented, minimising loss of life and property, and provide useful data.

A Stewart Whitley, Radiology Advisor, UK Radiology Advisory Services, Preston, Lancashire, UK and Former Director of Professional Practice, International Society of Radiographers and Radiological Technologists (ISRRT)

Charles Sloane, Principal Lecturer and Professional Lead for Health Sciences, Institute of Health, University of Cumbria, Lancaster, UK

Gail Jefferson, Senior Lecturer and Programme Lead for Diagnostic Radiography, Institute of Health, University of Cumbria, Lancaster; Reporting Radiographer, North Cumbria Integrated Care, Carlisle, UK

Ken Holmes, formerly Senior Lecturer, Institute of Health, University of Cumbria, Lancaster, UK.

Craig Anderson, Senior Lecturer, Institute of Health, University of Cumbria, Lancaster; Clinical Tutor and Reporting Radiographer, Furness General Hospital, Cumbria, UK