From Longman Dictionary of Contemporary Englishbe up the creek (without a paddle)be up the creek (without a paddle) (also be up shit creek (without a paddle) not polite) spokenPROBLEM to be in a very difficult situationIf I don’t get my passport by Friday, I’ll be up the creek. → creek
Examples from the Corpus
be up the creek (without a paddle)• I'll really be up the creek if I don't get paid this week.• What he learned from that interview was that Graham Ross was up the creek without a paddle.• Chairmen of football clubs are only in the papers and on the radio when the team is up the creek. 