A river divided
Yellowstone Park contains much of the headwaters of the river in the high plateau country that also gives rise to rivers such as the Snake, Madison and Gallatin. Because of its protected status, the Yellowstone flows relatively unsullied down from Two Ocean Pass and across the wilderness meadows of The Thoroughfare into Yellowstone Lake. From the outlet of that 136-square-mile body of water, the river roars through the Grand Canyon of the Yellowstone, over the famous and much-photographed falls, and exits the park near Gardiner, Mont.
While the river is wild in the park, it isn't free from controversy. Even there, contentious issues arise, such as how much the 1988 forest fires contributed to subsequent flooding, and whether elk are overgrazing the park and contributing to siltation problems downstream (HCN, 9/15/97).
While the river beyond Park County is more dominated by agriculture and faces less development pressure than the Livingston area, the Lower Yellowstone has its own set of challenges. Concerns include irrigation withdrawals from six major diversion dams below Billings, and the survival of several exotic fish species, including the pallid sturgeon, a fish with 150 million years of evolutionary seniority, but which hasn't managed any documented reproduction in 20 years.
Along the Lower Yellowstone, oil and gas refineries squat in the floodplains of both Laurel and Billings. Major livestock operations threaten water quality with their runoff, along with the assorted mix of pesticides, salts and heavy metals that pour back in with irrigation returns. Sewage effluents from a handful of Montana cities, including Billings (pop. 112,000) also wind up in the river.
The Yellowstone melds with the Missouri River in North Dakota, just across the Montana border. Some would argue, as John Neihardt did in his book, The River and I, that at that point, "the Yellowstone is the main stem and the Missouri a tributary ... All of the unique characteristics by which the Missouri River is known are given to it by the Yellowstone - its turbulence, its tawniness, its feline treachery, its grand caprices."