Joseph Creek is a small creek located in Beaverhead County, Montana. It can be found close to Chief Joseph Pass and was presumably named after Chief Joseph. It rises at 7100 feet of elevation, and runs for about six miles, with a 1000 foot elevation drop, before joining Trail Creek, which later joins the Big Hole River. Like most creeks or rivers in Montana, Joseph Creek gets most of its water from snowmelt, and thus has its heaviest flow in May or June, as the snowpack melts, and becomes much smaller during other months, when it is fed off of residual groundwater or rainfall.
None of which separates Joseph Creek from any of the thousands of other small montane creeks that run through the Rocky Mountains.
But there is one very important thing about Joseph Creek: it is the west most tributary of the Mississippi River. Which also makes it the west most stream that feeds into the Atlantic Ocean in the United States. If Hudson Bay is considered part of the Arctic Ocean, it is also the west most tributary of the Atlantic Ocean in North America. All an impressive list of accomplishments for a stream that can be hopped across. Not that the technicality of the stream's westernmost position really makes it that special: it is not as if it makes it any different from the other streams that might start a few hundred feet or a few hundred miles to the east. While the specific geological history of the Big Hole Valley, which forms a large western bulge into the Continental Divide is interesting, it is not the real interest. The real point of interest in Joseph Creek is just how far-flung the watershed of the Mississippi River is. While the flow of Joseph Creek is minuscule, several cubic feet per second, literally one part in a million to the Mississippi's millions of cubic feet per second; it is still the output of thousands of tiny streams, rivulets reaching deep into mountains thousands of miles from the Gulf of Mexico, that shapes North America's hydrological picture. It is this long chain of interconnections that makes hydrology and geography such a complicated and beautiful science.