The other reviewers are correct, it's bad. But for people, like me, who enjoy certain kinds of bad movies, it's a gold mine.
After the first shark attack scene, it goes on tediously for a bit, and I almost gave up on it. There is a lot of pointless dialogue, over explaining of things, etc... but if you can stay with it, it's got a lot of laugh out loud moments.
There is a non-sensical plot, TERRIBLE acting, writing and dialogue, laughable accents, baffling and unrealistic actions, attempts at touching & sentimental scenes for characters the audience cares nothing about, amateurish CGI, etc...
It's a real hoot if you're in to the that sort of thing. If you're wanting an actual "good" shark attack film, you should definitely avoid though.