To have your canal full

As in the sentence: "It's time to head back, you've got your canal full already"

German: "jemand hat den Kanal voll"

Meaning: "to get drunk". Refers unfortunately not to a Northern German obsession with man-made water channels but instead to the various components of one's digestive system (oesophagus, stomach etc) and their propensity to fill up after a night of chugging down booze (though the saying has featured in the headlines of many a German newspaper story about people falling into canals after a night out - who says the Germans don't have a sense of humour!). Perhaps comparable to the sayings "well-oiled" or "tight as an owl", though alas the imagery is less vivid in German. 

Variants: too plentiful to name.