When cameraman Hal Mohr was shown how the climactic flood scene was to be shot, he objected on the grounds that it would place many of the extras in jeopardy. Mohr told the executives that while the trained stuntmen knew what to expect and could prepare for it, the ordinary extras would have no idea what was coming, and many would be hurt. When his objections were overruled, he quit the picture, and was replaced by Barney McGill. During filming of the scene, the huge torrents of water overwhelmed the actors; three were drowned, one was so severely injured his leg had to be amputated and almost a dozen had broken limbs and other serious injuries.
Dolores Costello came down with pneumonia while working on this film. In later years she expressed the horrors of filming it as "mud, blood, and flood," having come close to drowning herself, in one sequence.
The "premiere" version, running 135 minutes, ran only at the opening engagement in Hollywood. By the time of the New York premiere some weeks later, the film had been trimmed by over 30 minutes. At least some of the cuts were of Vitaphone talking sequences that didn't work well. In particular, Paul McAllister (Noah/Minister) fared poorly, as all his talking scenes were removed.
In February 1956, Jack Warner sold the rights to all of his pre-December 1949 Warner Bros.-First National films to Associated Artists Productions. However, AAP edited the film down to 75 minutes, removing all the modern day sequences, and replacing the inter-titles of the biblical sequences with a pompous pseudo-biblical sounding narration. 100 minutes of the film have been restored, and the remaining 35 minutes are considered lost.