Movie about a serial killer who drowns his victims

I have seen this movie on HBO, between 10- 12 years ago. At that time I was not a Hollywood movie buff but I really liked the story. This was a suspense movie and am guessing it must have been made in between 1990 -2000.

There was a killer in the movie who drops live girls with heavy weights tied to their legs into a river. One lucky girl is saved by some cops driving by the river. Then they create a life size dummy of the girl and put cameras in the dummy's eyes. When the killer comes back to the river to check the girl's body, cops get his picture.