HOW CRESCENT BAR CAME TO BE
The road to CB doesn't fully reveal one of Washington’s most stunning destinations until you pass through 47° 13' 45.1"N, 120° 00' 57.6"W. And whether you’re surveying the area from this exact spot, or from your boat cruising the river with family and friends, most everyone who visits CB is captivated by the epic scenery here. From the wide-open views, to the dramatic basalt cliffs and powerful river, it’s a unique destination with a beauty all its own. But how did it come to be so awesome?
A VERY VIOLENT PAST
In a nutshell, CB has a very long and violent past, because it was forged by fire and water over millions of years. Both of these elements arrived in several great floods, which slowly built up, then rapidly scoured the landscape in massive displays of mother-nature’s power.
GIANT FLOODS OF LAVA
Starting about 17 million years ago, enormous amounts of lava flowed from huge cracks in the ground over 150 miles away from CB, near the present-day borders of Washington, Idaho and Oregon. The source of the lava was the same tectonic hot spot currently simmering beneath Yellowstone National Park in Wyoming. In case you’re wondering, the hot-spot didn’t move, the whole continent did, but that’s another story. Over the course of 11 million years, more than 300 of these lava floods covered nearly half of Washington State, large parts of Oregon and Idaho, and small parts of California and Nevada. Many of these fiery floods made it all the way to, and far beyond CB!
The scorching, slow-moving lava flows were nearly 2,000 °F, and hardened into basalt rock as they cooled, creating picturesque horizontal and vertical formations throughout the region. The horizontal lines, visible along nearby cliff faces clearly show the layers of lava deposited by individual flows. These layers average about 30 feet deep, but some are much deeper. The vertical formations visible within these layers are typically caused by the basalt cracking into tall five-sided columns as the lava cooled, a process which sometimes took 100 years. Here at CB, about a dozen of the newest lava flows are visible in the cliffs. The top layer of the cliffs is roughly 6 million years old, and reaches about 500 feet above the river, while the 17-million-year-old foundation lies a few thousand feet below the water line!
GIANT FLOODS OF WATER
Next came the water. About 15,000 years ago during the last ice age, a huge lake of glacier water formed near what is now Missoula, Montana. Glacial Lake Missoula grew to nearly 2,000 feet deep in places, and was contained for long periods by an ice dam in northern Idaho created by vast glaciers that extended from the north-pole, down through Canada and into northern Washington and Montana. Periodically, the ice dam broke, sending trillions of gallons of water, icebergs and rocks westward, across northern Idaho and down through parts of Washington, with some of it crashing right over the top of present-day CB! The Columbia River, also established from melting glaciers, was already flowing through here at the time, and some of the Missoula floodwaters took its path, roaring down the river and through this very spot at a depth higher than the cliffs, and as fast as 70 miles per hour! This happened as many as 100 times, and often the volume of water that blasted through here was greater than 10 times the flow of all the world’s rivers...combined!
AND THEN CB WAS BORN
The Missoula floodwaters were so powerful that they ravaged the ancient, cracked basalt landscape along their journey from Montana, forming huge gorges, canyons and coulees along the way. This is when the “bar” part of Crescent Bar came to be.
As the massive torrents of water raged across the land and down the river, huge amounts of rocks traveled with them. Powerful forces ground many of the rocks into smaller rocks and sand along the way, and this mixture became concentrated and deposited where the river turns, creating “flood bars”, in some areas hundreds of feet high.
Now, picture yourself at the top of the hill on Crescent Bar Road, where you ‘round the corner and catch that first awesome view of our favorite vacation spot. Geographically speaking, this happens at about 47° 13' 45.1"N, 120° 00' 57.6"W, and you’re now directly atop geologic Crescent Bar! The “bar” is the crescent-shaped flood bar formed by the enormous amounts of sand and rock deposited here as the river took a giant turn southward. From this vantage point, “Crescent Bar” can be seen in all the sand that surrounds you…to your right, in the steep shoreline that extends up this side of the river as far as you can see, and to your left, down river to the southeast, along the signature basalt cliffs that Crescent Bar visitors never forget.
AND WHAT ABOUT ALL THOSE RIPPLES ACROSS THE RIVER?
From atop Crescent Bar road, the rippled landscape across the river is nearly impossible not to notice or wonder about. That’s also a flood bar, called West Bar, and what you’re seeing are “current ripples” created by the huge, fast-moving currents of water raging through here when Lake Missoula drained. Most of us have seen small current ripples maybe an inch or two high in creeks, in streams or at the beach. But… the ripples at West Bar are around 30 feet high, enabling us to visualize that the scale and ferocity of the Columbia River ice-age floods must have been colossal!
So now you know how CB came to be, and if you’re like us, knowing this makes it way more fun to travel here, and to BE here!
Special thanks to Nick Zentner, Central Washington University professor of geologic sciences, for leading us to information that he and many others have put a tremendous amount of work into…and for giving us a passing grade on our paper! Here are some of his videos that are definitely worth watching. We're convinced this information will enhance your CB and eastern WA experiences for years to come.