Effects of Glacial Development on Dam Safety in Norway

Dams in Norway, as many others across the world, are susceptible to a multitude of different hazardous glacial mechanisms. These can have serious consequences on downstream communities and populations and must be considered to retain a high level of dam safety practice. They can range in severity and origin, but are possible to assess through a properly applied risk analysis process following their identification. Although these hazards are numerous, focus is placed on three specific mechanisms; the first bound from climatic conditions with increased precipitation and rapid melt of ice, the second from glacial lake breaching or drainage, and thirdly, calving and icefall processes. Multiple mechanisms can intertwine and lead to dam failure or catastrophic events, most of which have not been considered or researched to great extents within Norway, as compared to other regions. As the climate continues to change, and new hazards are presented at a more frequent rate, these perspectives are needed more than ever. This paper will employ several empirical and qualitative methods to determine characteristics of various glacial lakes, probabilities leading to dam failure, and eventually outline the assessment procedures for 12 different dam cases investigated across Norway, distributed amongst different glacial systems. The risk analysis method of choice are event trees, which can be developed in both a quantitative and subjective manner without the requirement of immense data. These analyses have their limitations that will be discussed, but as a high-level screening, resulted in the findings of dams characterized by high-risk in all three primary focuses.