go down the tubes
verb1
US, Euphemistic, Idiomatic Synonym of go down the toilet: to fail; to degenerate rapidly.
- The entire plan went down the tubes when they found they couldn't get strawberries in December.
- Meanwhile, Susan's own workplace shut down, and she found herself "on the street with no job and a two-year-old kid. I was trying my damndest and I was going right down the tubes."1990 February 4, Pam Mitchell, quoting Susan Moir, “Pro-Union And Queer”, in Gay Community News, volume 17, number 29, page 17: