Glacier National Park - Rivers and Streams (U.S. National Park Service)

NPS photo

McDonald Falls

There are 1,557 miles of perennial streams in Glacier. McDonald Creek is the longest stream (over 25 miles) inside of the park boundary, but the North Fork and Middle Fork of the Flathead River, much larger streams, bound the park on the west and south. Countless other intermittent streams exist during melt-off, some raging torrents at times, but many dry up as quickly as they started.

Glacier's water can be considered the headwaters of the entire continent. From Triple Divide Peak, a droplet can theoretically split 3 ways and eventually make it to the Pacific, Atlantic and Hudson Bay watersheds. As part of the source water for North America, its cleanliness is important to everyone on the continent. And it is, relative to nearly everywhere else, clean. Hopefully, the protection given Glacier since 1910 ensures that quality for future generations.

Streams are corridors for spawning fish, a huge and relatively unknown diversity of aquatic invertebrates, water ouzels (dippers), harlequin ducks, beavers, otters, kingfishers, and numerous other animals.

Riverbeds are superficial boundaries of a stream. In many places, water moves through porous gravels and pebbles underground, and emerges again farther downstream. Recent research at the edge of Glacier in the Middle Fork Flathead River has turned up entire "interstitial" ecosystems, permanently underground, containing over 80 organisms. So far, nearly 50 of these creatures of the dark were previously unknown to science.