Carbrook Golf Club in Queensland, Australia, probably has the most dangerous water hazard around. Their golf course lakes have several bull sharks swimming in them which means you won't find me fishing after any lost balls on that course! How did the sharks get into the lake? According to Carbrook's website, "In the early 90's, the Logan River burst its banks, resulting in large volumes of water covering the course for an extended period of time. As the water level dropped, large volumes of fish species were contained in the many creeks and lakes of Carbrook. For years, rumours abound of a shark in the lake. It was rarely sighted but often talked about. In more recent years, sightings have become a regular occurance, often more than one being seen at a time."
Seeing is believing, so check out this video for yourself:
