Increasing flood frequency, suffering and loss of life, and capital losses are the results of human land use practices in our watersheds
Reports of human loss and suffering from flooding are far too frequent. And while the reports heighten our perception of the problem, they still don’t fully illustrate the growing impacts of floods on people and their homes. Or accurately reflect the cause.
According to the World Bank report Cities and Flooding, A Guide to Integrated Urban Flood Risk Management for the 21st Century, the 10-year moving median number of reported flood events is rising steadily and was a full 16 times higher in 2010 than 50 years earlier.
Floods are nothing new. They are natural events that have been happening for millennia, shaping the earth we live on and creating much of the natural bounty that supports us.
Still, we like to villainize nature when it brings us harm. Floods, like wildfires, have gotten a very bad name because of the harm to people we associate with these events.
But Mother Nature is not the problem. Dr. Gilbert White, the late founder of the internationally-recognized Natural Hazards Center in Boulder, Colo., put it well: “Floods are acts of nature; but flood losses are largely acts of man.” We must take heed of this wisdom as we plan for resilience – especially in light of climate change.
Increasing flood frequency, human suffering and capital losses are some of the negative effects of historic and current human land use practices in our watersheds.
While we work very hard to reshape the earth to suit our desires, many decisions we thought would improve our lives result in unintended consequences. That’s because we have failed to think holistically about the watersheds we live in. They are interdependent systems. But in our desire to engineer solutions to control the land, rivers and nature in general, we end up degrading the very components of those systems that could keep us safe and resilient.
Perhaps most notable are the insults we inflict on river floodplains. In our zeal – or perhaps arrogance – to try to ‘tame’ our rivers, we submerge floodplains under deep reservoirs created by dams, we build settlements and industrial manufacturing facilities on them, we mine floodplains for gravel, and we drain and cultivate them for modern agriculture.
For example, according to Syilx, the Okanagan Nation Alliance, 96 per cent of the historic riparian floodplains in British Columbia’s Okanagan Valley are gone.
Many people think of river floodplains simply as the areas beside a river where water would go if it spilled over its banks. This narrow view has emerged because we have grown accustomed to engineering our rivers, to straighten them and prevent them from overtopping their banks.
But, as Dr. Stanley Gregory of Oregon State University puts it, “floodplains are a vital part of the river, not an area adjacent to the river. If you don’t believe that, sit on a floodplain long enough and you’ll realize you are in the river.”
Functioning floodplains are actually one of nature’s most impressive structures and provide us with huge benefits. Without any effort from humans, floodplains control and reduce flooding, reduce erosion, improve surface water quality, increase biological productivity and recharge groundwater aquifers. In addition, they provide temporary cold water storage for release into the river in late summer when flows are low and water temperatures can get too high for fish. They provide for the harvest of wild and cultivated products, and yield a steady stream of cultural, aesthetic and recreational use values.
But the natural benefits we get from floodplains are in severe decline because of human alteration and land use.
Yet these natural buffers could be a major part of the solution, providing safety and resilience as we try to adapt to a world increasingly influenced by climate change. Holistic land use planning at a watershed scale could be vital.
When it comes to natural systems, it certainly is more expensive to fix something you have broken than it would have been to protect it in the first place.
But continuing with business as usual will mean the human costs of natural disasters will continue to increase at an unprecedented rate, far surpassing the cost of investing back to holistic watershed management today.
And the news reports of human loss and suffering from flooding will only intensify.
By Barry Wilson
Barry Wilson is a systems ecologist and cumulative effects expert at CE Analytic Ltd.
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