This paper develops an analytical framework to investigate the relationship between water and armed conflict, and applies it to the ‘Summer War’ of 2006 between Israel and Lebanon (Hezbollah). The framework broadens and deepens existing classifications by assessing the impact of acts of war as indiscriminate or targeted, and evaluating them in terms of international norms and law, in particular International Humanitarian Law (IHL). In the case at hand, the relationship is characterised by extensive damage in Lebanon to drinking water infrastructure and resources. This is seen as a clear violation of the letter and the spirit of IHL, while the partial destruction of more than 50 public water towers compromises water rights and national development goals. The absence of pre-war environmental baselines makes it difficult to gauge the impact on water resources, suggesting a role for those with first-hand knowledge of the hostilities to develop a more effective response before, during, and after armed conflict.