Big Serge conducts a detailed analysis of the Russian dam break. From Big Serge at bigserge.substack.com:
A different kind of leak

It is probably safe to say that the current week (June 5-11, 2023) is shaping up to be one of the most significant of the entire Russo-Ukrainian War. On Monday, all eyes were on the Ukrainian Armed Forces and their much anticipated summer counteroffensive, which began with a series of battallion level attacks across the breadth of the theater. After these initial assaults in the Ugledar, Bakhmut, and Soledar sectors began to collapse with heavy losses, it looked like the topic of discussion for the forseeable future would be Ukraine’s prospects for breaching strongly held Russian defenses.
Instead, the entire Ukrainian offensive was overshadowed by the sudden and entirely unexpected failure of the dam at Nova Kakhovka on the lower Dneiper.
Let’s be clear about one thing: the destruction of this dam marks a qualitative change in the course of the war; a dam represents an entirely different tier of target. There is a broad sense that dams are not legitimate military targets, as they fall in the category of “objects containing dangerous forces”, along with things like sea walls, dykes, and nuclear power plants. However, attacks on dams are not without precedent, and the legality of such attacks is a complicated and thorny topic – it is not so simple as to say “attacking dams is a war crime” in all circumstances.