The only thing I can think of which comes close to that is https://storiesonline.net/series/639/echoes-in-time
The only thing I can think of which comes close to that is https://storiesonline.net/series/639/echoes-in-time
The description makes me think of https://storiesonline.net/s/71259/zombies-werewolves-vampires-and-other-improbable-things. The fit is rather loose though; you have to read 'bad guys' as zombies, I think there's a river but it doesn't feature prominently, 'girls college' is a sorority and even 'politician' is a little loose. It's a good story: I go back and re-read it every now and then, just for the fun of it.
Here. He pulled everything in August 2009. I don't know if he posted somewhere else as well.