Switzerland is offering prize money to get munition out of its lakes. For decades, the Swiss military has dumped munitions in the lakes. The army earlier thought that dumping munitions underwater is safe. So now, Swiss lakes hold tens of thousands of tonnes of munition. But Switzerland is urging public to share ideas for munition clean up and the best three ideas will share the prize pot of $57,800. How will the clean-up work? How costly will it be? Why did the army not stop dumping ammunition in the lakes? Our report tells you.