There is a small leak from the dam? Ruh Roh!
Astro tended to speak a kind of English except that words with beginning consonants were replaced with an "R," and "R" was inserted in front of vowels.
Scooby-Doo was less fluent, but was given "Ruh-roh" as a kind of running gag when things were going bad.
Now "Ruh-roh" is sometimes used as a jocular trope where dogs are concerned, as in a recent news story about a dog who was accidentally released by Air Canada from his cage at the San Francisco airport. Rough meaning: "I goofed" or "I'm in trouble."
"Alright Astro, you asked for it, no outdoor privileges all weekend."