Only with a Lot of Planning
The description of the vampire reads, "Each round of immersion in running water inflicts damage on a vampire equal to one-third of its maximum hit points—a vampire reduced to 0 hit points in this manner is destroyed." Emphasis mine.
I'll admit 12 gallons per person per round is a lot, but immersing--that is, submerging or completely covering the vampire beneath running water--is going to take a lot more than a few castings of the spell create water. You and your meddling friends are going to have to engineer a Scooby-doo style trap with dams and such to make the water actually run for that to work.
The Pathfinder vampire is killed by running water probably as a baptism metaphor, but also probably to give low-level players a method of destroying an otherwise powerful undead by bull rushing it into a river and winning grapple checks. The spell create water--a 0th-level spell usable infinitely in Pathfinder--I'm almost certain isn't supposed to nor intended to kill again Count Dracula or Baron Blood.