It's How You Play the Game - S4-E19
Character mistake: On scene at the vehicle accident, John palpates a pulse on the driver's leg and tells Roy that he's got a good strong foot pulse. Then when Roy's on the line with Rampart we hear him say, "He has a strong fetal pulse," but presumably Roy certainly must have meant to say, "strong pedal pulse."
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy