From Guardian blog of J.Lovelock.

[Akkuratix]

There is a phrase "be up to creek", can´t find explanations from my dictionaries. Could you help, please?

[amigos4]

There is a phrase "be up to creek", can´t find explanations from my dictionaries. Could you help, please?

I believe you might be thinking of the idiom "up a creek". The idiom is similar to being "up a river without a paddle";
If you are up a river without a paddle, you are in an unfortunate situation, unprepared and with none of the resources to remedy the matter.

[Tdol]

Or up the creek.