Lesions in the Land:

The Ragged Edge Between Streamflow, Watersheds, Land Use and Salmon

A transcript of an address delivered to the Annual Meeting of the British Columbia Salmon Foundation, May 14, 2001 by Will Marsh

British Columbia is facing a monumental problem. Its salmon populations are declining precipitously and it has everyone – politicians, fishermen, scientists, environmentalists and citizens in general – in a tailspin. What’s causing the change? Fingers are being pointed in every direction. Candidate causes include ocean warming, overfishing, long-term biological cycles, water pollution and abuse of watersheds.

In general the candidate causes fall into two classes; (1) those that can not be addressed by groups such as yours – these include ocean warming and long-term biological cycles – and (2) those that can. Among those that can, streamflow and stream pollution are within your reach. These you can do something about. Are they the leading causes? We don’t know. But they are certainly significant contributors.

To address these problems we must understand the relationship between a stream and a watershed because watersheds are the sources of stream streamflow. In other words streams are the products of the watersheds in which we find them. It follows that as watersheds change so change their streams.

But herein lies a fundamental problem. Believe it or not, we don’t have a good understanding of the watershed – stream relationship especially among those who work with the land, clearing forest, building roads and developing communities and farms. Just how does the watershed feed the stream with water? What processes are involved and how are they changed by land use? Are there ways of making land use more compatible with those processes and the needs of streams as fish habitat?

As a boy, I was intrigued by streams. I held them in mystical awe...they were spiritual places for me. When I approached one with my fishing pole, my pulse quickened and the rest of the world fell behind me.

In the woodlands of the south shore of Lake Superior where I was raised the streams were small, clean and quick. They were habitat to brook trout, mink, otter, muskrat and beavers. In the summer I fished in them and in the fall and winter I ran trap lines along them.

As I grew older and listened to the stories about the woods from my father, grandfather and uncles I became more curious about streams themselves – where did they begin and end; why were some large and others small? Their names still ring clear in my mind: the Stuts, the Big Indian, the Hurricane, the Fox, the Seven Mile.

The question of stream sources caught my fancy and I searched out the origin of several small streams near home. Near our ball field was a small creek – the Mill Yard Creek. One day I followed it into the hills beyond our village and found a single spot where its flow emerged from the foot of a large hill. There it was, clear and simple – water discharging from the earth. Beyond this hill my uncle told me about a creek called the Boiling Springs. I set out to find it and did. It literally boiled out of the ground and flowed into a small lake that emptied into Lake Superior.

Much later in life I had come to more or less the same conclusion as the ancients had – the Greeks of Pericles time argued that streams originate from springs in the ground. But what fed these springs was a mystery. The Greeks had an idea – which turned out to be wrong – but I hadn’t a clue. Like the ancients I didn’t understand groundwater. In addition I made No connection between streams and the geographic area that feeds them, the area we call a watershed. The basic concept of a watershed is based on observable run-off and never once in all my time in the woods did I see surface run-off - water pouring over the ground and into stream channels. The sandy, forested soils of Lake Superior apparently took in all the water rain and snow could deliver and left none to run to find its way over the ground and into the stream channels.

Roll the film of life ahead a decade or so... I’m in the university and there I learn about the American Western Surveys of the late 1800’s where field scientists reached the remarkable conclusion that the surfaces of the continent are shaped by run-off – that is simply by water pouring off the land in sheets, rivulets, gullies and streams.

The evidence was compelling – look at the Dakota Badlands where George Custer chased the Lakota Sioux, the Grand Canyon where John Wesley Powell made his famous float trips and Palo Duro Canyon where the US Army ousted the Comanches – all carved by run-off. Watersheds in this vast open prairie are easy to see; the stream – land connection is a simple concept to anyone caught out there in a rainstorm.

J. W. Powell, leader of the Western Surveys, returns to Washington DC and tells congress that the West should be organized politically according to watersheds – not on a square grid like Thomas Jefferson advised. Nothing comes of it.

Forty years later the hydrologist, Robert Horton, defines the critical processes of watersheds drawing attention to overland flow – the run-off generated by stormwater. Stormwater becomes central in our vocabulary and we define streams according to the area of ground that feeds them – overland flow – the watershed. Engineers take charge of watersheds. Watersheds and their streams became overwhelmingly stormwater systems.

Years later in my career I realize something is not right about the assumptions on the relationship among stormwater, streamflow and watersheds as defined in the engineering studies for land development projects. I harken back to my time as a boy finding streams emerging from springs with no evidence of any surface water contributions. No Stormwater at all!

And then I run across the research of a hydrologist named J. D. Hewlett who measured run-off and streamflow in the heavily forested watersheds of the Appalachians. He measured these watersheds for many years and never once recorded surface run-off. There was no evidence of stormwater. Hewlett’s streams were fed by subsurface flows. He reported his observations many times. The results were indisputable. Heavily forested watersheds no, or very little, surface run-off. They feed streams via underground flows, mainly water moving in the soil layer and the material just below it.

Broadly speaking, I conclude that there are two species of watersheds in the world; (1) forest watersheds and (2) grassland watersheds. Forested watersheds run on almost exclusively on subsurface water; grassland watersheds run on stormwater and variable amounts of subsurface water in their lower reaches. Grassland watersheds produce flashy flows, lots of sediment and where land use is involved, lots of pollutants.  Forested watersheds produce slow, steady flows and clean water – until land use gets involved. In your part of the world, in this great, forested mountain-land watersheds are fed by two underground water sources (1) shallow and (2) deep.

When we apply land use to forested watersheds we transform them into grassland watersheds – that is we change them into stormwatersheds. One of the most serious consequences of land use development in “big” forest landscapes is the practice of DITCHING. This practice is justified in part by the misconception that these watersheds are naturally drained by stormwater and ditches and other stormwater drains are only going to help them function more efficiently. We build ditches along roads, across farms, between residential lots, under streets – everywhere. The ditches cut into the shallow source of groundwater and divert it into surface flows. These flows bleed the watershed. In addition they open the watershed to a new source of water, stormwater run-off, its sediments and other pollutants. In a study we’re conducting in one small coastal watershed near here we learned that between 1931 and 1996 the total length of drainage channels increased from 6 kilometres to over 70 kilometres. The 64 kilometres of new channels are all manmade! And they are all jammed into a drainage area of only 5 square miles or 13.5 square kilometres.

Ditching is particularly serious here in British Columbia because the winter rains saturate the surface layer of soil and subsoil. Almost everywhere this layer is composed of sandy, gravelly material lying over dense glacial till. It takes on and stores large amounts of water and then slowly releases the water throughout the winter, spring and summer. Ditches cut into this layer, intercepting the water and hastening its delivery to streams. Ditches can conduct the water at a rate more than a hundred times faster than the soil can. For a short while stream flows increase but in spring and early summer they decline as the as the supply of water in the soil is drained away.

So we’ve lacerated our watersheds and in so doing have changed their flow rates and water quality making them faster and dirtier. As a result streams are tougher places for fish to do their business.

My message to you is to move from streams to watersheds in your consciousness, apply pressure to engineers, road builders, farmers and homeowners to stop ditching and draining. Its time to suture our watersheds back together. Apply pressure to the ditch builders to stop the bleeding!

I began by saying there may be multiple causes to the problem of declining salmon stocks. Its a confusing situation but everyone is working hard to make amends. We’re often befuddled but we are not lost. I’m reminded of a story about the famous American philosopher Yogi Berra who, on his way to a ceremony at the Baseball Hall of Fame in Coopertown, New York, becomes impossibly lost in the labyrinth of New York highways. His wife senses the dilemna but understanding male pride about being lost says nothing. Yogi pushes on. The minutes and miles tick by. Unable to take the mounting frustration any longer she finally says, “Yogi, I think we’re lost.” Yogi replies, “We may be lost, but we’re making good time.”

Thank you

Will Marsh is a Landscape Architect who has  relocated to the Comox Valley where he teaches with the University of British Columbia Landscape Architecture Program. Will maintains a close relationship with the Watershed Stewardship Community in the Region

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