Celebrating water

Oldman River. Photo: Bob Costa

With our growing concerns around water, Lorne provides an inside view of our most precious resource.

The Geography of Water

by Lorne Fitch, P. Biol.

Water appears gentle, even delicate but is the moulder, polisher, manipulator, builder, and leveller of landscapes. At Dry Island Buffalo Jump, on the Red Deer River, this tableau revealed itself on the climb up to the island in the sky, the “dry island” of rough fescue grassland. These snapshots of the geography of water are everywhere.

Recent rains, probably aided by snow melt coalescing on the slopes have worked on, eroded, shaped, and transported soil, rock, and sand, depositing these materials downslope, storing them for future movement. Over time water has sculpted this plateau, creating a separate island of elevation, and continues to shrink it in size.

The materials on the alluvial fans where the drainages meld with the flats were, a short time ago, part of the slopes. In the exiting spaces are rills, gullies, and canyons, all thanks to water. Against water and often freeze/thaw action even the bedrock is not immune. As a liquid lever it undercuts, overwhelms, carries away, demolishes, builds, creates, and sustains landscapes. Water has time on its side, time beyond our estimation.

Over time and from countless tributaries and seemingly insignificant drainages, like the slopes of Dry Island, eroded materials are transported to rivers, like the Red Deer River. The water there expresses its thanks for the inputs by displaying a shade of the colour of the landscape eroded. The fine silts, clays, and sands stay in suspension with the current of the river. Given time to settle in a glass, you have a layered cocktail of landscape pieces.

You can hear the grinding of this aqueous sandpaper through the hull of the canoe. Rivers have abrasive tendencies. Over time, moving water is a belt sander, a reducer of big into little and the little ground into fine silts and clays. Resistance is futile. Water humbles the mightiest of mountains and the tiniest of hills by introducing the humility of erosion.

Rivers have momentum, as gravity gives them energy. That kinetic energy is translated into work, further eroding, transporting, and depositing eroded material, at least temporarily. There is a cumulative addition of the work done by the drainages that feed the river.

Sometimes there is a détente of sorts, as trees and shrubs, especially the cottonwoods and willows, bind the bank materials together in a matrix of kilometres of roots. They push back and resist the constant tug of the current which is implacable at eroding the bank. But it’s often a temporary win, maybe a measured retreat.

In the fullness of time, water’s arch ally, the river forecloses on the mortgages held on the land, especially during floods, and pieces of the floodplain built over time wash downstream. In the equivalent of riverine leapfrog, those materials will be redeposited, as the river slows and new stream banks and floodplains are built. And so the pattern repeats in meander bend after meander bend. Rivers not only convey water, but they also convey landscapes, each at different speeds.

Water, in its liquid form, is incompressible. This frustrates us because we would like, in flood times, to shoehorn more water into river channels, instead of having it spread out over the floodplain where we have inappropriately built. Floodplains are a river’s essential escape clause and safety valve. There, flood flows can be temporarily stored and slowed, allowing much eroded material to be deposited.

When water freezes it expands with a hydraulic force that shatters, belittles rock. Mountains crumble. Water in the solid state of glaciers formed so much of the Alberta landscape and beyond. In geological time, that happened just yesterday. The scars and marks of glacial action, of ice flows over a kilometre thick, are still evident as are the meltwater channels of current drainage networks.

A winter freeze creates an ice capstone to water. Yet it continues to flow in rivers, extracting from the shallow groundwater bank account laid away in the previous spring. That a river would flow, in the winter during subzero temperatures is a minor miracle. It’s a testament to the water we cannot see, an amount perhaps equivalent, maybe more, to the visible water in the channel.

There is an equal but opposite transformation during the spring thaw. Spring temperatures unleash the combination of a wrecking ball and a bulldozer of ice blocks wielded by flood flows. They scrape, abrade, and reconfigure with massive weight and momentum. River banks, trees, and shrubs have to reconcile with this irresistible force. When the ice chunks jam temporary dams are created, raising water levels to heights almost unimaginable. These create watery highways, overpasses for fish to circumvent otherwise impregnable waterfalls.

There is deep, subterranean water—fossil water—because of its great age. When it was stored, how much there is, and how it moves is its secret. What that water records in its chemistry is a world of long ago, a world untampered with by us.

Atmospheric water, the clouds, hold us in suspense—will it rain, hail, or snow? The delivery of moisture is essential to life but the frequency, intensity, timing, especially the amount, is out of our control. In whatever form—a gas, a liquid, or a solid—water reminds of essentials and humbles us.

Like the veins and arteries that transport our blood, water runs through, over, and under the landscape, bringing life. The circulatory system of water is complex, easily disrupted, compromised, and interrupted. We give water too much advice—go here, not there, be close but not that close, be available for our needs (but neglect the needs of water). We alternately control its flow or unleash it with both predictable and unforeseen consequences. Our appetite for water is insatiable, yet the supply and quality shrink, sometimes, or often, because of our folly.

As creatures mostly composed of water we might display some fealty to it, recognizing and protecting its virtues and mechanisms. We are water and could stand some of the humility water creates.

Lorne Fitch is a Professional Biologist, a retired Fish and Wildlife Biologist and a past Adjunct Professor with the University of Calgary. He is the author of Streams of Consequence, Travels Up the Creek, and Conservation Confidential.