BEDLOAD

Photo Credit: Peter W. Fong

In the summer of 2018, Peter W. Fong led a first-ever expedition from the headwaters of Mongolia’s Delgermörön River to Russia’s Lake Baikal. Backed by substantial grants from the Transglobe Expedition Trust, the Trust for Mutual Understanding, and the Taimen Fund, his team travelled more than a thousand miles by camel, horse, kayak, and rowboat, collecting scientific specimens and interviewing local residents along the way. The following is an excerpt from a book-length manuscript entitled, Rowing to Baikal.

Rain in the night, tentative at first, then as insistent as freeway traffic, the noise of it thinning occasionally but still there in the background, until finally the stars appear and the temperature drops below freezing. The ducks and cormorants that flocked around our camp at evening have dispersed by dawn, gone with the storm.

The river is beyond bank-full. In some places, roiling clouds of sand and silt rise in visible swirls, churned from the bottom as if by some giant beast. In the larger whirlpools, I can feel the water sucking at the chines, trying to bear the boat downward like a twig or a leaf.

I am alone at the oars, with Lanie and Guido following in the other boat. Recalling our unscheduled portage a few days ago, I am all eyes and ears. Each time we encounter an island, I squint hard at the river’s dark waves, trying to gauge which channel is carrying more water. I don’t make this calculation out of idle curiosity. Under these conditions, the wrong decision can provide a visceral lesson in hydrology, the sort of failure that can fill your mouth with mud.

A river transports sediment in two basic ways: suspended load and bedload. The suspended load is what I can see: the fine particles that make the water look murky, the larger grains that swirl upward and around in boils and eddies.

As its name implies, however, bedload travels closer to the riverbed. These even larger particles are too heavy to rise toward the surface but not heavy enough to withstand the force of the current, and so they proceed downriver “by a combination of sliding, rolling, and saltation,” where saltation means “motion consisting of a series of short hops, often with temporary rests, before propulsion forward for another hop or short excursion.”[1]

I can’t see bedload in this flood, but I can hear it. Sitting in the middle seat of the drift boat is like sitting at the receiver of a dish antenna. The noise seems to come from the air: a distant rasping, whispery and fricative, not at all like the transparent murmur of water.

These are the sounds of collision—not only particle against particle but, in some cases, boulder against bedrock. The volume rises and falls with changes in depth and current and the composition of the river bottom, as if the Selenge is a living voice trying to warn me away from a risky decision. And yet it’s hard not to feel like I’m choosing at random. When two channels appear to be roughly the same size, does it matter which one we take?

Not usually. Most channels are short enough for me to see the next confluence, where the river rejoins itself. In these instances, both options are safely navigable. The uncertainty arises where the river braids, turns, then braids again – hiding the conditions of passage from my view while simultaneously subdividing the flow into smaller and smaller fractions.

Photo Credit: Peter W. Fong

In low clear water, it would be easy to avoid the too-shallow places. In an area of open banks, with grassy meadows or broad gravel bars, a wrong choice might mean merely having to drag the boat for a few yards.

This morning, however, the banks and islands support a heavy growth of willows, mature trees that rise 30 feet or more, interspersed with spreading poplars, their trunks as big around as my waist. And the water is so high that the willows’ lower branches sieve the surface, adding even more commotion to the flood’s clamour.

According to Luna Leopold, the author who introduced me to the word saltation, “The nature of a river channel is not closely constrained within a narrow range of characteristics by physical laws that must be fulfilled. The river responds to physics, but there remains much latitude in the morphology that a channel may assume.”[2] This is a scientist’s way of saying that a river’s reaction to flood can be unpredictable. It can flow fast and true, overtopping its banks and burying all obstacles conveniently beneath a cushion of water, or it can carve itself a new bed, uprooting trees and carrying off tons of dirt and rock.

As it turns out, knowing all of this doesn’t help me one bit. Eventually I find myself between two islands of unknown size, in a channel that I don’t like at all.

The problem is not lack of water. In fact, there is plenty more than enough – running deep and fast between opposing banks thick with willows.

The current is so strong that I can’t stop the boat by rowing upstream. The best I can do is keep the bow pointed down the centre of the channel. In some places, the trees are so large that their limbs create a canopy over the river. In others, the banks are so close together that I have to pull in the oar blades, lest they strike against a protruding branch and send the boat spinning out of control.

At one point, I notice with relief that Lanie is keeping her distance behind me. That way, if I run into trouble, she’ll have a few seconds to watch the results and weigh her options.

The worst moments come after I pass beneath a low bower of trees. Several are already leaning dangerously, their roots undermined by the river’s force. Any one of these, I think, is large enough to completely block the channel. And then the river turns abruptly, leaving me blind to what’s ahead. I sit up even straighter than usual, shoulders tense, oars at the ready.

The brown water hurries beneath the boat, anxious to reach its destination. The yellow leaves flutter in the wind. When the channel widens perceptibly, I steel myself for the next narrowing. Instead, the trees withdraw, like clenched hands relaxing.

Soon I can see blue sky overhead, and a low ridge of mountains on my right. A hundred yards later, we are back in the main river.


[1] Luna B. Leopold, A View of the River (Harvard University Press, 1994), p. 185.

[2] Ibid., p. 271.

Peter W. Fong

Peter W. Fong

Peter W. Fong is the author of the award-winning novel, Principles of Navigation, and a chapter book for children and adults, The Coconut Crab. His stories and photos have appeared in American Fiction, Gray's Sporting Journal, the New York Times Sophisticated Traveler, and many other publications. He lives in Tangier, Morocco.

Peter W. Fong is the author of the award-winning novel, Principles of Navigation, and a chapter book for children and adults, The Coconut Crab. His stories and photos have appeared in American Fiction, Gray's Sporting Journal, the New York Times Sophisticated Traveler, and many other publications. He lives in Tangier, Morocco.

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