Oregon’s biggest mud puddles are once-and-future inland seas
Summer Lake, Abert Lake and Goose Lake were once all part of a vast network of seas surrounded by lush vegetation. In dry years they can evaporate completely — which led to some confusion on the Applegate Trail one year.
By Finn J.D. John — January 15, 2017
EDITOR'S NOTE: This column is a rewriting and thorough re-researching of a much shorter column first published in April 2009, which you’ll find here.
Westward bound on the old Applegate Trail in the early 1850s, the party of settlers halted in confusion at the shore of a vast, placid lake. Its waters stretched nearly all the way to the horizon, with just a thin rim of dimly glimpsed ridges beyond to indicate that they had not reached some sort of preternaturally calm ocean.
The settlers, by now, had passed a few of these alkali lakes as the trail brought them westward. This one was the biggest they’d seen.
Its size wasn’t what was startling about it, though. What confused them were the wagon ruts — the well established Applegate Trail was marked by a deep set of wagon-wheel grooves that carved a path across the high Southeastern Oregon plateau over which they journeyed. And those ruts led straight into the lake.
Of course they tried to follow them into the lake for a few hundred yards, but it quickly became clear that its water, in addition to being miles wide, was also deep — deep enough, at least, to stop a wagon train.
But the western sky lay on the other side of the big water, and there was nothing for them to do but to travel around it. They toiled their way north, and then west, and then south again, following the rim of the vast lake to its opposite shore, a journey of something like 100 miles.
Sure enough, when they got there, they found the heavy wheel ruts of the Applegate Trail climbing nonchalantly out of the waters of the lake and continuing on their way westward toward Eugene City.
Upon their arrival, the emigrants learned that nobody else knew anything about the vast lake they’d had to detour around. They wondered where it might have come from.
It remained a mystery until, several years later, there was another season of dry weather — and the lake dried up once again.
Today the disappearing lake is known as Goose Lake. It’s a vast shallow basin, shaped like an arrowhead, right on the Oregon-California border just south of Lakeview. And right now it’s as dry as it’s ever been … but that will probably change when this winter’s snows melt.
Several springs drain into Goose Lake; but Goose Lake drains nowhere. It merely collects rainwater and snowmelt during wetter years, and lies there baking in the high-desert sun, quietly evaporating away, until it’s either replenished by another year’s rainfall or dried up into a powdery moonscape.
The year 1846 must have been a dry one, because that’s the year the Oregon Territorial Legislature commissioned brothers Jesse and Lindsay Applegate, with eight other early Oregonians, to find a safer alternative to the Oregon Trail. For Jesse and Lindsay, the quest was personal. On their own journey several years before, they had lost two Applegate children, drowned beneath the roaring cataracts of the then-untamed Columbia as the party struggled to cross it in their caulked wagons.
The trail the brothers’ party blazed diverged from the main Oregon Trail path at Fort Hall in Idaho, and dove down into northern Nevada and California before dipping back up into southern Oregon, crossing the Cascades, and then turning north along roughly the same path taken by Interstate 5 today, en route to the southern Willamette Valley.
But apparently the late 1840s were pretty dry, and they unwittingly left a big, miles-wide obstacle squarely in their path.
The lakes of Lake County, including Goose Lake, are sort of unusual. They are, essentially, vast mud puddles, and their shores expand and contract according to climactic conditions.
During the last Ice Age, those mud puddles were more like a network of small inland seas, many hundreds of feet deep and covering hundreds of thousands of acres, surrounded by lush vegetation and home to a wide variety of animals as well as human communities. The shores of one such lake, which covered the future townsite of Fort Rock under several dozen feet of water, was the home of a community of people 14,000 years ago, who left behind a small trove of woven sagebark sandals and coprolites (very old dried-out or fossilized excrement) that form the oldest evidence of human habitation in the Americas. And you can still see where the shores of those old inland seas used to be, in wave-worn features in the surrounding rimrock. Fort Rock itself — the geological feature, not the nearby town named after it — is an especially good place to observe this.
With the changing climate, though, those seas literally dried up. Year over year, the water in them evaporated away. And thus, the dissolved salts and impurities of an entire small ocean wound up concentrated in the waters of a cluster of little lakes and ponds — many of them quite large in surface area, but relatively shallow.
Some of these dried sea-beds can be dangerous when conditions are bad; if one ingests enough alkali salts, either by drinking the water or by breathing the blowing dust, it can change the body’s acid-base balance in disastrous ways. It’s thought that the dusty bottom of one alkali lake, near the town of Jordan Valley close to the Idaho border, sickened and killed Jean-Baptiste “Pompey” Charbonneau, the frontier mountain man who had been the baby born to Sacagawea on the Lewis and Clark expedition in 1905.
Lake Abert in particular is very salty; it and Summer Lake are the remnant of an ancient inland sea called Lake Chewaucan. Abert’s waters are filled with a dense population of brine shrimp, which are an important food source for the migrating waterfowl that blacken the Lake County sky in the spring; but like Goose Lake, it, too, is drying up.
But this winter’s heavy snowfalls suggest that help, in the form of plenty of snowmelt to fill the lake and relieve the stressed brine shrimp, may be on the way.
And when the Earth enters its next ice age, those ancient basins will be ready and able to resume their old role as the containers of Oregon’s own network of high-elevation inland seas.
(Sources: Gulick, Bill. Roadside History of Oregon. Missoula, MT: Mountain, 1991; Orr, Elizabeth and William. Oregon Geography (6th Ed.). Corvallis: Oregon State University Press, 2012)