But by hanging over a boulder or bridge, trout can be observed, too. They are perfect creatures of their habitats, apex predators in a crystalline world of insects, dace, and crayfish. Trout are flawlessly hydrodynamic, with bullet-shaped snouts and skin so smooth that scales seem to vanish. They hover patiently behind rocks, dart into the swift current for food, or push upstream against massive currents.
Far more than a sportfish, the trout is a living filter, a sample, of the river itself.
It not only rakes hyper-oxygenated water over its gills but soaks up the river itself through the permeable membranes of its body. At the Glenwood fish hatchery in New Mexico, a second-generation hatchery worker, Laura Lee Hammer, explained how too much carbon from an old forest fire can kill. An unusual bloom of nitrogen will cause fish to crowd a raceway to avoid contact, she said: “They’re like sheep that way.” The hatchery assiduously maintains pH levels between 6.0 and 9.0 of acidity.
Yet across the West, thousands of old mines hang like chemical swords of Damocles over the clear, rushing world of the trout. The mine above Durango, Colorado—the Gold King—that spilled its contents earlier this month was shuttered in the 1920s. The mine is just one among 500,000 in the United States. The cost of cleaning them up fewer than 200 hardrock mines alone is estimated between $24 and $54 billion.
But no one—no humans anyway—wants to pay those bills directly, or even indirectly. So, some 50,000 mines linger in a federal backlog, namely in the West, and only one in 10 of these has been repaired. Old mine owners have vanished into history and new owners say they have no responsibility for what took place years ago. In Washington, the mining industry has even sought federal indemnity from future lawsuits.
Yet even before this disaster, the Gold King spelled trouble. The creeks connecting it to the Animas were frequently polluted as water interacted with toxic chemicals which, in turn, leached heavy metals from the rock. The Gold King was such trouble it was a candidate for federal Superfund dollars. But a coalition of local interests reportedly didn’t want the stigma that came with federal money; it might frighten off tourists and their money.
After all, the town and the river that ran through it made for a spectacular scene. Big waters teemed with rainbow, cut throat and brown trout just off, say, 32nd Street, a fishery so good that anglers would travel from all over the world. Nearly 100 feet wide in places, the water muscled its way over giant rocks and down into deep holes, so abundant with trout that the state awarded the river its coveted gold medal fishery status.
But trouble appeared last year and it was the trout that told it. Some fish, about 120,000 in recent years, were stocked and some were wild. In 2014, though, state game officials found that the population of fish—particularly young, wild brows, which are perfect monitors of a river’s health—had actually declined. This was the first time in nearly 20 years that the river did not meet the state’s gold-medal standard. And while the precise cause wasn’t clear the eyes of local conservationists turned upward toward the Gold King, by then a troubled wastewater treatment operation poisoning creeks.