Do you think it would be okay if I....?

I have an interview tomorrow for a 6th form college placement and the dress code there is a suit so obviously I was going to wear one to the interview. However, I was trying it for size and spilt a drink on it damaging it and the dry cleaners aren't open and I now don't have a suit to wear. I'm thinking about going in smart casual clothes and explaining the situation to them. Or do you think I should try and rearrange the interview?