Jim says he used to work "for the Johnstown Company" - likely a reference to Bruce Springsteen's song, "The River" which itself is quoted moments later by Ray. Johnstown, Pennsylvania, is most famous for an 1889 flood, caused, like the flood in this film, by a dam failure.
A teaser trailer touting its original title, The Flood, was released months before its original May 2, 1997 release date. However, the film was delayed till January 1998, not only allowing for more time in post-production but an overhaul in the film's marketing campaign. As the disaster movie had found renewed interest in the late 90's with films such as Twister (1996) and Dante's Peak (1997), Paramount wanted to differentiate the now-retitled Hard Rain from those by focusing new trailers on the action and crime elements rather than the storm at the center of the plot.
The trivia items below may give away important plot points.
There are quite some similarities between this movie and Broken Arrow (1996): both have Christian Slater as the main lead, who receives help from a local woman; in both movies, he finds out that his colleague is abusing his job to commit a crime, and he is forced to keep an object out of the hands of his assailants, who chase him through a deserted area. Both movies also contain a scene where Slater nearly drowns. Both films were written by Graham Yost, and John Woo, who directed Broken Arrow, was considered as director for this movie before Mikael Salomon took over.
Christian Slater gets knocked out and wakes up in a jail cell. In real life, Slater was convicted of assault while under the influence of alcohol and drugs, and sentenced to three months in jail before the movie was released.