Some munitions are at depths of 150 to 220 metres, but others in Lake Neuchatel are just six or seven metres below the surface. Now, the Swiss defence department is offering 50,000 francs (£45,000) in prize money for the best idea to get it out. The munitions pose two risks, he said. First, despite the fact it is underwater, there is still a risk of explosion, because in many cases "the army did not remove the fuses before dumping the munition".