I admire films that dare to deal with specialised subjects like this. On the whole I think the film's portrayal of the lives of those involved in the Vajont disaster -- and of the events leading up to it -- was good. However, there are quite a few technical inaccuracies and some of the characters are partially fictionalised.
The film twists the facts a bit to follow a more stereotypical disaster movie plot & build up the tension, portraying the engineers as worried and afraid when in fact they were calm and confident that they were in control of the situation right until the end. The film makes a drama about the water level, and that the water level was slightly over the critical 700m mark when the landslide took place, suggesting this was the cause of the disaster. In reality the engineers had already taken the water down to SADE's critical level - 25m blow the dam crest. However, the problem was that the "critical" level simply didn't apply - the flood was caused by the speed of the landslide when if finally happened, which no-one had predicted correctly.
The special effects are best when they are subtle - for example in visualisations of the dam and the village of Longerone during the first ninety minutes or so of the movie. However, in the finale, they failed to convey a sense of the awesome power this flood really had. We are talking about a 150m high wave of solid water coming over the top of the dam, then being funnelled down the narrow gorge beyond at 140 km/h. In the film it initially looked like buckets of water being thrown at a model in slow motion. The spray particles were too large, and there was no dark mass of water behind the spray. The only time it looked frightening was when we were given a glimpse of the wave racing down the narrow gorge, preceded by an enormous, howling rush of air tearing the valley sides apart and carrying debris along with it. This air blast was also depicted arriving in the village below, like a sudden hurricane falling upon the bewildered villagers. Another nice touch was the blue flashes seen by the villages up in the valley at night, at the moment of the landslide, caused by the collapse of power lines. This was a frightening premonition of the destruction that followed.
The film twists the facts a bit to follow a more stereotypical disaster movie plot & build up the tension, portraying the engineers as worried and afraid when in fact they were calm and confident that they were in control of the situation right until the end. The film makes a drama about the water level, and that the water level was slightly over the critical 700m mark when the landslide took place, suggesting this was the cause of the disaster. In reality the engineers had already taken the water down to SADE's critical level - 25m blow the dam crest. However, the problem was that the "critical" level simply didn't apply - the flood was caused by the speed of the landslide when if finally happened, which no-one had predicted correctly.
The special effects are best when they are subtle - for example in visualisations of the dam and the village of Longerone during the first ninety minutes or so of the movie. However, in the finale, they failed to convey a sense of the awesome power this flood really had. We are talking about a 150m high wave of solid water coming over the top of the dam, then being funnelled down the narrow gorge beyond at 140 km/h. In the film it initially looked like buckets of water being thrown at a model in slow motion. The spray particles were too large, and there was no dark mass of water behind the spray. The only time it looked frightening was when we were given a glimpse of the wave racing down the narrow gorge, preceded by an enormous, howling rush of air tearing the valley sides apart and carrying debris along with it. This air blast was also depicted arriving in the village below, like a sudden hurricane falling upon the bewildered villagers. Another nice touch was the blue flashes seen by the villages up in the valley at night, at the moment of the landslide, caused by the collapse of power lines. This was a frightening premonition of the destruction that followed.