طغیان رودخانه

Question

رودخانه طغیان کرده است .

Answer 1

The river has burst its banks

Answer 2

The river has outpoured." 

The Verb form is extracted from American Heritage Dictionary:

out·pour ( out-pôr“, -p ½r“) v. tr. out·poured out·pour·ing out·pours 1. To flow out rapidly; pour out. n. ( out“pôr”, -p ½r”) 1. A rapid outflow; an outpouring: an outpour of sympathy. out·pour “er n. 

"Spate" and "Overflow" are two other synonyms for that word.