When I was growing up, this was something we said all of the time. Given that many small farm streams were crossed without bridges, which worked find most of the time, a swollen stream would cause problems. Most of the ones on paved roads had bridges or culverts by that time, but not all of them and everyone still clearly knew what that saying meant – even if the threat wasn’t very real anymore. Well, at least we thought we did….but maybe not.
Did you know the saying “God willing and the Creek don’t rise” was in reference to the Creek Indians and not a body of water? We didn’t.
It turns out that the phrase was written by Benjamin Hawkins in the late 18th century. He was a politician and Indian agent. While in the south, Hawkins was requested by the President of the U.S. to return to Washington. In his response, he was said to write, “God willing and the Creek don’t rise.” Because he capitalized the word “Creek” it is deduced that he was referring to the Creek Indian tribe and not a body of water.
January 2021: Hat tip to Maria whonotes that the collection of Benjamin Hawkins’s letters has now been digitized and can be read at this link. A search for the word “rise” does not produce this phrase, so it appears that the body of water theory was correct after all.
Native Heritage Project 
Actually this is not proven. There is a lot of controversy about this fairly common folk saying.
I doubt it will ever be possible to prove the source of some of these old sayings,but they sure are alot of fun…This post set me a thinkin bout some things we grew up saying that we took from our elders…for example when one is astonished you say ” Oh my Stars!” Or when you havent seen someone in awhile you say… “I aint seen Hide nor Hair of em since”..and there was plenty of times I was told…”quit rootin around an causin such a ruckass!”…usually refering to me being in Granmas garden…and one can never forget the simple…”Skeedaddle!” Now “the devil may know”Where those sayings come from…
False folk etymology. It is a paraphrase of a popular biblical saying from James 4:15, and while there are scores of citations to the phrase in the sense of the waters rising, in the US and Europe, there is not one shred of evidence of a reference to the Creek nation.
Take a look here Michael: http://www.genealogynation.com/creek/
Well, whether it’s Creek or creek, it would still have much of the same effect…you won’t be going where you thought you would or could. I grew up with that saying and I’ve said it more times than I can count. Be it God’s will, or, we go to war, my “plans” will go according to one of those two choices.
“Not one shred of evidence” is a clear invitation to fault the writer. From another source “Some historians attribute Benjamin Hawkins as having been the first person to ever say these words and he did so in a letter to the President of the United States.
Hawkins served under George Washington as General Superintendent for Indian Affairs (1796–1818) and had responsibility for the Native American tribes south of the Ohio River, and was principal Indian agent to the Creek Indians.
In a letter to the Commander in Chief, Hawkins stated that he would return to the nation’s capital, “God willing and the Creek don’t rise.”
“Hawkins, college-educated and a well-written man would never have made a grammatical error, so the capitalization of Creek is the only way the phrase could make sense… and the reference is not to a creek, but The Creek Indian Nation. If the Creek ‘rose’, Hawkins would have to be present to quell the rebellion.” writes one commentator.”
Had he written “… the Muskogee don’t rise!” ir “…if the streams do not rise!”We would not have an ambiguous statement