How Unique is Triple Divide Peak?

Most people familiar with Glacier National Park are likely familiar with Triple Divide Peak. The significance of this mountain, near Cut Bank, is that it's the point where rain water flowing down its slopes eventually ends up in the Pacific, Atlantic or Arctic Oceans.

Geographically, the summit of Triple Divide Peak lies at the point where the Northern Divide (or Laurentian Divide) meets the Great Divide (or, what many people call "The Continental Divide").

While hiking to Medicine Grizzly Lake last summer I wondered how many other triple divides existed in the world. After doing a little research on the internet I really couldn't find a definitive answer to this question. On its Triple Divide Peak page, Wikipedia states that it's "one of the few places on the Earth whose waters feed three oceans".

However, the article on continental divides on Wikipedia has a world map showing drainage areas into the major oceans and seas of the world. The map uses data from the USGS Hydro1k project from the Earth Resources Observation and Science (EROS) Center. Looking at the map below (click here for a larger version) you can see there are several places around the world that have triple divides. Look a little closer and you'll notice that most have drainage areas flowing into two oceans, but the third flowing into a sea, such as the Mediterranean, or the Gulf of Mexico. One such triple divide lies near Hibbing, Minnesota, where water either flows north into the Arctic Ocean, east into the Atlantic, or south into the Gulf of Mexico. In my view though, the Gulf and the Atlantic are one in the same.

I guess the real question I had was how many triple divides have water flowing into three of the four great oceans of the world. Surely there had to be at least two on the European-Asian continents. Again, looking at the map below, you'll see at least four triple divides on the Euro-Asian continents. However, in all four cases, one of the drainage areas flows into what is known as an endorheic basin, where water doesn't drain into an ocean. A perfect example of this is the Great Basin, which covers much of Nevada, and parts of Wyoming, California, Utah, Idaho, and Oregon. According to this map, most of south-central Asia doesn't drain into an ocean.

Therefore, from what I can gather, it appears that Triple Divide Peak is the only place in the world that has water flowing into three of the four great oceans of the world.

Before making this great assertion, however, there is one major caveat to consider. There seems to be a dispute as to whether waters from Hudson Bay discharge into the Atlantic Ocean or the Arctic Ocean. According to the article on the Hudson Bay page on Wikipedia:

Hudson Bay is part of the North Atlantic Ocean. Sometimes the Hudson Bay and Hudson Strait basins are considered part of Arctic Ocean despite that their waters flow predominantly to the Atlantic. Some sources describe Hudson Bay as a marginal sea of the Atlantic Ocean, or the Arctic Ocean.

Does anyone have any definitive information? Please let me know if I am incorrect on this assumption.


Jeff
Hiking in Glacier.com