Thrill of Multnomah Falls (Troutdale, OR)


There are few things more thrilling than standing near a stupendous waterfall. The feeling is almost visceral, mesmerizing. Some people claim that they feel better when standing next to a waterfall, maybe having something to do with the production of enormous amounts of negative ions (oxygen molecules with an extra electron) that research has shown improves mood and rids the air of pollutants.

As our previous visits to Multnomah Falls were under less than ideal weather conditions, we decided at the last minute to take another trip there since there was little chance of rain today. Along the way, we also stopped to see Wahkeena Falls.

After Yosemite Falls, Multnomah Falls just outside Troutdale has been identified by the U. S. Forest Service as the tallest year-round waterfall in the nation. It can easily be reached from the Historic Columbia River Highway, only a half hour outside Portland. A short trail leads to a footbridge from which you can observe the upper falls more closely.

There would not have been such a spectacular attraction were it not for many major lava flows during the area’s geologic history. The devastating Missoula Floods that reshaped much of Washington State did much to create Multnomah’s present form. They ripped away the fractured basalt, leaving behind steep cliffs and cataracts.

multnomah falls

Burney Falls


Often described as one of the most beautiful falls in the world, 129-foot Burney Falls is accessible in a state park far removed from a major thoroughfare. Continuing northward along Highway 89 in California, we wanted to make the falls a stopping point. Meltwater from Burney Mountain makes its way down through the porous volcanic rock (basalt) down into underground aquifers. Some of the water is forced above ground about a mile up from the falls and forms Burney Creek, while the rest of it moves through the underground reservoir and out the openings in the cliff face. If you look squarely at the falls, the water seems to originate not only from above but also from the rock wall. Even when the creek dries up during the summer, water continues to flow because of these underground channels. The flow rate is estimated to be 100 millions gallons per day.

On the Trail of the Pacific Northwest’s Ice Age Floods


A rendering of an Ice Age flood (image usage permission granted by Stev Ominski)

One of the biggest surprises about Northwest natural history is that there were many catastrophic floods during recent geological times that dramatically altered the landscape of Washington state. Almost half the state was inundated. This hypothesis was first put forward by geologist J Harlan Bretz in the 1920s.

These floods are thought to have swept through the state many times during periodic ice ages. During the last ice age, a lobe of a Canadian glacier blocked the Clark Fork River drainage in Idaho, causing glacial meltwater to fill up the valleys of the Mission, Bitteroot and Rattlesnake Mountains to form Glacial Lake Missoula, estimated to have been 3,000 square miles. High above Missoula, along the  mountain slopes, there are strandlines of many prehistoric lakes. More than once, when the water level became high enough, the ice dam would be breached and let loose 500 cubic miles of water in 48 hours, a cataclysmic megaflood that drained to the southwest into eastern Washington, down through the Columbia gorge, into parts of western Oregon, even extending as far south as Eugene, and out to the Pacific Ocean via the Columbia River. At one time, present-day Portland was buried under 400ft of water. It is estimated that the flow rate was ten times greater than all of the world’s rivers combined. The onrushing deluge carried with it not only unimaginable amounts of water and debris but enormous boulders, some rafted on icebergs over hundreds of miles before being deposited (glacial erratics). The Willamette Valley in Oregon has erratics up to 40 tons. These repeated inundations stripped off the topsoils of eastern Washington to lay bare the hard basaltic layers underneath (from previous volcanic lava flows as early as 17 million years ago) that earned this area its name, the  channeled scablands (coined by Bretz). To this day, after many thousands of years, you can still see evidence of the flood(s).

The scablands would not be as spectacular if not for the basalt layers. One common form that appears in the Northwest is columnar basalt, vertical cracks forged in the basalt layers as they cooled very slowly. Less resistant to erosion is basalt entablature, usually on top of  columnar basalt, that has cooled more rapidly and therefore don’t readily form clean vertical cracks but show a more random fracture pattern. When monstrous floods attack these layers, columnar basalt can more easily be plucked away, leaving behind steep, vertical channels in the landscape, called coulees. Most coulees are dry, unlike canyons that still have rivers flowing in them.

Example of columnar and entablature basalt, ingredients for creating the flood landscape of the channeled scablands

My wife and I set out on a road trip to see firsthand some of the spectacular evidence that these floods left behind. I picked out a few important sites that we could fit into a three-day trip. Going by car is a great way to visit these places, especially with the help of references such as Bruce Bjornstad’s classic book as a guide. This book

Our first stop was an overlook just outside Quincy. A short half-mile hike to the edge of Babcock Ridge gave us a stunning view of the resort of Crescent Bar over 600ft below and giant flood-produced current ripples on a bar across the Columbia River. These ripples are gigantic in scale, about 20-50ft high and spaced over 300ft apart, estimated to have been submerged under 600ft of water. At that height, the waters overtopped portions of the ridge that we were standing on, carving out the gigantic Potholes Coulee just to the south.

Giant current ripples on West Bar along Columbia River. (Note water vessel for scale)

Another phenomenon that fast-moving water creates are potholes. High-energy tornadoes of water (or kolks, as they are called) tore out huge holes in the bedrock, sometimes more than a mile wide. Some are now lakes and ponds, but most of them are dry. There are many examples of this, including the gigantic one we saw north of the Frog Lake trailhead on Morgan Lake Road in an area called the Drumheller Channels and the lakes below Dry Falls.

A kolk created this giant pothole in the Drumheller Channels. (Note that I’m in the center of the photo which only shows a portion of the pothole.)

Drumheller Channels are an amazing network of interconnected, braided channels that were sculpted out of the earth by the deluges from the northeast. Below is a panorama that I spliced together from seven photos taken along our drive on Morgan Lake Road.

A glimpse of the Drumheller Channels from Morgan Lake Road (click to enlarge)

As dramatic as the landscape looked from the road, we just couldn’t visualize what this area looked like from above. With the help of Google Earth, it can clearly be seen. This area was unique enough that it was designated a National Natural Landmark by the National Park Service.

Drumheller Channels looking northwest toward Potholes Reservoir (Google Earth)

Along the northern shore of Lake Lenore are a series of caves that were carved out by the swirling flood waters, plucking out the looser columnar basalt more easily than the more resistant entablature above it. You can see them as you’re driving along Hwy 17. A turnoff for the attraction leads to a parking lot where the trailhead is located. Beyond the stone staircase up a short distance, the trail divides to the left and right. Some of the caves were large enough for prehistoric people to have used as shelters.

One of the many flood-cut caves along Lake Lenore

Further, just before Coulee City, is Sun Lakes-Dry Falls State Park, an area used for recreation and a showcase for observing the handiwork of ancient floods. Spanning 3.5 miles wide and averaging 400ft in vertical drop, Dry Falls is the remnant of the largest falls that the world has ever seen, ten times the size of Niagara Falls, but now a dry cataract. You can try to envision this cataclysmic spectacle from the Dry Falls Interpretive Center on Hwy 17, two miles north of the main park entrance. (Un)luckily for us, the center was closed for the entire day due to staff meetings. But, the overlook is open year-round (weather permitting). From here, you can gaze at the immense cataract and the plunge pools, now lakes and ponds, that the waterfalls created.

Satellite view of Dry Falls cataracts  looking south (Google Earth)

Dry Falls panorama from Interpretive Center overlook (click to enlarge)

As we drove past Ephrata toward Moses Lake on Hwy 17, we couldn’t help but notice the vast flood plain littered with boulders. When the flood waters broke free from the Grand Coulee, they spread out into the Quincy Valley and deposited these boulders knocked free from the Grand Coulee and sources upstream, some as high as 60ft. This area is known as the Ephrata Fan, an expansion flood bar, where there is little productive farming.

Glacial erratics along Hwy 17 between Ephrata and Moses Lake (Google)

While almost all flood-cut waterfalls in the channeled scablands are now dry cataracts, there is one that remains, a whisper of its former self, but spectacular nonetheless. Palouse Falls flows year-round, but its most impressive displays are during spring melt when the volume is greatest. At the foot of the falls is a large plunge pool. The falls are part of the Palouse River system, which continues through the breathtaking Palouse River canyon downstream to join the Snake River. Unlike typical canyons, these coulees were sheared by the ice age floods.

The best place to see it is at Palouse Falls State Park, accessed by a spur road from Hwy 261, 17 miles from Washtucna. We enjoyed a picnic lunch here (there are nice picnic tables) and hiked a trail that hugged the edge of the coulee, including one that led to a very narrow ridge directly above the pinnacles to the left of the falls.

Palouse Falls used to tumble over the entire gap but is now a shadow of its former self.

Beyond Palouse Falls lies the Palouse River canyon. Note the vertical walls typical of flood-sculpted coulees.

This illustration by artist Stev Ominski dramatizes what the event probably looked like.

A rendering of the flood through Palouse River Canyon (image usage permission granted by Stev Ominski)

Interestingly, ninety percent of Washington’s vineyards are planted in soil deposited by or as a consequence of the ice age floods. Almost all the silts and minerals that used to cover the scablands got stripped away and laid down in the Columbia and Walla Walla valleys where the state’s finest vineyards are located. The Willamette Valley in Oregon, known for its pinot noir, also has soil similar to that from Lake Lewis, the temporary 1,200-foot flood-produced backwater lake that rose behind Wallula Gap in eastern Washington and covered the Tri-Cities area (Pasco, Richland and Kennewick).

Only three days long, our road trip was certainly not comprehensive enough to see even a fraction of the geological evidence of a megaflood. But, with a new understanding of what took place, I will never look at eastern Washington with the same eyes as before. It was worthwhile and humbling to take the trip.

Update (8-4-15): Lying between McMinnville and Sheridan near Oregon’s Highway 18 are glacial erratics that were left behind by one of the Missoula floods. Erratic Rock State Natural Site showcases a 36-ton argillite specimen that is presumed to have been encased in an iceberg that got rafted by a flood and deposited here when the water receded. It is the largest erratic in Oregon. What makes this particular set of rocks so unusual is that they came from Canada, the only ones known to have traveled beyond our neighbor’s borders.

erratic rock

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Rainbow Bridge National Monument (Utah)


The last time we were in Page back in 2008, we decided against visiting Rainbow Bridge because it seemed pricey just to look at a natural bridge, even if a spectacular one. Ever since, I wondered if we’d missed an opportunity, not knowing if we’d ever return to Page. As luck would have it, we did come back, and this time we were going to go, as much to see this natural wonder as take the cruise on beautiful Lake Powell.

It is easily accessible by boat tours on Lake Powell. Although the monument itself is located in Utah, the tour’s starting point is Page in Arizona. Tours also originate from Bullfrog Marina in the northeastern part of the lake in Utah. We took the half-day cruise from Page.

It took two hours to reach Rainbow Bridge. Once we got near, the boat slowed down and maneuvered into a small canyon, one of countless others along the lakeshore. It’s an entirely different sensation to move through these canyons on boat instead of on foot. The burnt orange walls glide past.

Side canyon

Because the water level of Lake Powell has been receding, what used to be just a short walk to the monument’s base from the boat landing now is about a mile away. In one sense, it’s more dramatic when the entire span of Rainbow Bridge suddenly appears as you round the final bend in the hiking trail.

Rainbow Bridge
At the monument site itself, there was a very entertaining park ranger who had no end of fascinating stories and facts to tell. We could’ve listened to him for hours. Imagine a natural rock bridge almost as high as the Empire State Building. Imagine too that it is the largest natural bridge in the world, standing at 290 feet tall and 275 feet across. This is Rainbow Bridge.

Rainbow Bridge

The story of its creation is the part of the story of the entire Colorado Plateau. Here, a stream undercut a fin of Navajo sandstone and started the process of bridge-building through water erosion. Eventually, like all such bridges, Rainbow will collapse as other bridges are being created.

The weather had been overcast almost the entire day, with forecasts of heavy rains. As we were returning to the boat from the monument, an epic rainstorm opened up. All around us were deafening claps of thunder and bright flashes of lightning. The rain was so heavy that we got to experience something rarely seen on tours, ephemeral waterfalls by the dozens, cascading down the sandstone mesa tops, some so voluminous that they were spewing out like hydrants and some so choked with red earth that they were rusty in color.

rainbow-bridge-waterfall
While we were away from the campsite, that same rainstorm practically blew our tent away. Luckily for us, a neighbor was good enough to re-stake everything and gather our camp chairs that had blown away. We learned from another couple at dinner that their 4WD slot canyon tour was visited by a tremendous hailstorm that covered the ground in several inches of white.

The tour lasted about 5 hours in total. A long day, to be sure, but worth the experience of the monument and the thrilling storm afterward.

Manoa Falls (Honolulu)


A hike through lush rainforest is the one to Manoa Falls, about 1½ miles from the bus stop to a viewing area of the falls. At the foot of the trailhead is a parking lot where a snack shop also was selling mosquito repellent. We decided to take our chances. As soon as we started the hike, we were beset by the tiny buzzers, so we hightailed it back to the shop and swallowed our pride.

The hike itself is easy, gaining elevation gradually, but recent rains made the path very muddy. Boardwalks on portions of the path helped. In many places, exposed tree roots will force you to consider where you plant your feet. Along the way, there are many flowers and plants, giant ferns, mosses, wild guava trees, bamboo forests, and more. The falls, 150 feet tall, are not approachable beyond a protective fence, where a sign warns of danger beyond.

In all, the hike is a pleasant one when the weather is nice and rewards hikers with many visual splendors.

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