Imagine pouring out a glass of water. Where does the water go?
After soaking your computer or floor, it would eventually flow to join a greater body of water and become part of a larger drainage system. Where I grew up, outside of Milwaukee, my water would join with Lake Michigan. In the Twin Cities, where I went to university, it would flow into the Mississippi River. From Jackson, Wyoming, where I’m writing now, it would combine with the Snake River and flow into the Pacific Ocean. But Glacier National Park, where I worked in the summer of 2017, has a unique little point called Triple Divide Peak. Triple Divide Peak marks the division of three major watersheds. If you poured out your water on top of Triple Divide, it would flow into the Columbia River watershed, and eventually the Pacific Ocean; it would flow into the Nelson River watershed, and eventually Hudson Bay and the Atlantic Ocean; and it would flow into the Mississippi River watershed, and eventually the Gulf of Mexico and Atlantic Ocean.
Triple Divide is commonly hailed as unique and significant because water from its peak flows into three oceans. That depends on whether you think Hudson Bay connects to the Atlantic or Arctic Ocean, and there is certainly some dispute surrounding that. There’s another triple divide peak in Canada that flows directly into the Arctic and Pacific Oceans, as well as into Hudson Bay. So, depending on what you think about Hudson Bay, either Canada or Montana has a triple ocean divide. The International Hydrographic Organization considers it to be in the Arctic division of oceans and seas, so that might be a win for Montana. The significance of these triple divides as possibly flowing into three oceans also depends on your definitions of oceans, which isn’t always straightforward. Regardless, though, they all flow into three distinct and major drainages. (As a side note, the naming schema for water around triple divides tend to follow a similar structure; surrounding rivers, streams, and glaciers are often named for the drainage they join. Triple Divide Peak in Montana has the Pacific, Atlantic, and Hudson Bay Creeks. Snow Dome has the Columbia and Athabasca Glaciers, as well as the Dome and Stuttfield Glaciers.)
As an exhibits specialist in Glacier, my job was to design interpretive wayside panels with our seasonal media team. One of our selected topics was Triple Divide Peak. (If you’ve ever been to a national park, or really any public land or well traversed road, you may have seen a wayside on the side of the road. They’re meant to be quick interpretations of what you’re seeing, an opportunity for visitors to connect to the place they’re in without necessarily interacting with a ranger.) I always thought I had a pretty good grasp of what a watershed was and how drainages worked from my time studying and living by the Mississippi, but I learned so much throughout the course of making this wayside.
Unique in its geography and the sheer size of its combined drainage, Triple Divide Peak drains into basins that cumulatively cover 1,823,000 square miles. It connects incredibly different portions of North America. To the east, the Great Plains lead into the agriculturally productive interior of the United States, and eventually the Mississippi Delta. The Flathead River joins with the Pend Oreille, then flows into the Columbia, where human influence has inspired massive dams and conservation, in turn. The northern rivers, despite historic use by First Nations, are now known for the presence of fur traders and hydroelectric development in more recent years (a common motif along rivers and land in North America).
Triple Divide Peak brings together three major drainages in northwestern Montana, almost in Canada. I knew this, I had told people this, and I thought it was a pretty neat concept. And I knew that continental divides acted as drainage divides. But I hadn’t reasoned through the idea that Triple Divide, in order to flow to three different oceans, must be a place where two continental divides meet, in this case the Great Divide and the Laurentian Divide. Snow Dome in Canada is at a similar intersection, where the Great Divide and the Arctic Divide meet. There are other triple divides that aren’t at the intersections of continental divides, though. In Wyoming, Three Waters Mountain marks the triple point where the Colorado, Columbia, and Mississippi watersheds meet. California has its own Triple Divide Peak in Tulare County, where the Kern River, the Kaweah River, and the Kings River watersheds meet. Europe has triple divides in Switzerland (Witenwasserenstock and Lunghin Pass, if you’re curious). Asia, interestingly, has no major triple divides because of the massive endorheic basin in its interior. Endorheic is one of my new favorite words. When water collects without an outlet to a river or ocean, it forms an endorheic basin. Much of the Sahara Desert is part of one endorheic basin, draining into Lake Chad. Antarctica is the only other continent with a multi-ocean triple divide, and that again depends on how you define oceans.
As singular as Triple Divide is, we wanted to emphasize connection over division in our wayside sign. The same drops that enter the water in Glacier will make their way to three oceans. They might flow past your house, or they might grow the food you eat. With so many points of connection and collection across the world, we have to consider the greater impact of our actions.
Melting snow and ice provide a critical source of water, sustaining habitats for countless plants and animals, here and downstream. Protecting these pristine waters also supports agriculture, recreation, and industry across the continent. As the climate warms and glaciers recede, the store of water that nourishes the continent will diminish. Though Triple Divide Peak seems far away, what happens here has effects that reach close to home.”
Feller, Quinn. 2018. “Where the Water Flows: Understanding Glacier’s Triple Divide Peak.” Open Rivers: Rethinking Water, Place & Community, no. 9. https://editions.lib.umn.edu/openrivers/article/where-the-water-flows-understanding-glaciers-triple-divide-peak/.
Download PDF of Where the Water Flows: Understanding Glacier’s Triple Divide Peak by Quinn Feller.