Deliberate mistake: During the rescue of the car at the top of the draw bridge, The Boat approaches and radios in to say that they have a diver standing by. Then after Johnny shouts, "Are you all right?" the rescue boat is shown again, but this time it's a flipped shot - note that everything is reversed from the prior shot.
Deliberate mistake: When O'Brien shows up at the nurses' station for Dixie's answer, after she declines the offer Dixie walks off to a patient who's brought in by the police, and the last closeup that's shown of O'Brien is flipped - note his hair is parted the opposite way and the background is backwards.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy