River Talk

January 2010 Archives

There is a (too) common trope in many discussions of restoration ecology that posits some kind of desired "pre-contact" ecological system that would serve, then, as a desirable future condition. "If only we could get back to the North American landscape before Columbus," these arguments seem to imply, "we'd be able to live happily and sustainably on the planet."

There are many problems with this supposition, of course, among the most obvious being that it completely disregards the indigenous people as agents of change both before and after the appearance of Europeans. 

More recent and sophisticated understandings have suggested that instead of some kind of "turning back the clock" people interested in restoration might want to consider what the critical landscape functions and processes are, and work toward restoration of some of those key connections and dynamics.

I'm certainly no expert on the science of restoration ecology, but a recent project that has garnered a lot of press attention appears to have developed a subtle approach to the subject, as well as a dynamic interaction and communication/education program. The Mannahatta Project takes as its starting point the question of what Manhattan Island was like before the arrival of Henry Hudson in 1609. The interactive map is really a cool way to show that Times Square formerly was an area where streams crossed (Crossroads of the World, on a different scale!) and the like.

But Eric Sanderson and the other scientists and staff at the Wildlife Conservation Society who have developed this project have a bigger goal in mind than just a cool web site and education materials. In a TED talk last summer, Sanderson posed the question of how Manhattan can still be habitat for 12 million people 400 years from now. What can be learned from the earlier biological and physical systems that will let the same number of people, say, live there, using a much smaller amount of space, and leaving the rest for growing food and managing clean water supplies.

I wish the project had more evidently talked to descendents of the Lenape people who inhabited the island when Hudson showed up, but that may still be in the works. In the meantime, the innovative use of technology to convey new scientific insights is only the most obvious reason to spend some time exploring this impressive effort to build a smarter future based on detailed knowledge of the past.
St Anthony Falls and Downtown Minneapolis
When you stand on the banks of the Mississippi River in the Twin Cities, particularly in the spring with snowmelt swelling the stream, it looks like a big river.  At St. Anthony Falls, the river flow averages 12,000 cubic feet per second (cfs), or almost 90,000 gallons per second.  In New Orleans, by contrast, the river is 50 times as big, averaging some 600,000 cfs.  According to Wikipedia's article on the Mississippi River (forgive me, all of my research methods teachers!!) the outflow of the Mississippi is only around 9% that of the Amazon.
 
Now THAT's a lot of water!
 
But according to the most recent edition of the World Savvy Monitor rivers only make up 2% of the globe's fresh surface water, with lakes comprising the vast bulk of the rest.
 
So that means that Mississippi River cities such as Minneapolis, New Orleans, and all points in between have an adequate water supply, right?  Well, yes and no.
 
According to panelists at the community panel "Perspectives on Water in Our Changing World," the question of "adequate" water supply is complicated, and will only grow more complex over time.
 
The panel was put on by World Savvy, a national nonprofit that specializes in programs that encourage school-age children to "think beyond your borders" and become aware of their connection to global issues.  Water is their most recent focus; hence the community panel, co sponsored with the University of Minnesota's Water Resources CenterBreck School, the Freshwater Society, and Minnesota Public Radio.
 
So what are some lessons for the Mississippi that can be learned from an understanding of global water issues?  Space does not permit a full discussion of the very interesting and informative panel, but important points included these:

  • Mark Seeley, Minnesota's State Climatologist, expects that trends in climate change will continue to concentrate rainfall in heavier storms, which occur at seasons that are historically unusual.  That is, a thunderstorm that brings over 2 inches of rain to a town in the Mississippi valley will wash unusually heavy sediment loads into the river and its tributaries if the storm happens in the fall, when the ground has been cleared of crops.
  • According to Deb Swackhamer, connections are the key, between what happens to the land in terms of urbanization and changes in land use and their impact on streams and in terms of the connections, poorly understood in detail, between ground water and surface water.
  • Joan Nephew suggested that a primary need is a cultural shift, analogous to the growth of recycling.  Just as it has become second nature to separate bottles, cans, and paper from trash, and there are substantial industries devoted to recycling used materials into new uses, so we will need to begin thinking and practicing wide scale recycling of water, and reusing, for example, dishwater.
 
Rivers connect us to each other; we all live downstream of some people and upstream of others.  On the Mississippi, the fifth largest river in the world, our water is connected to all the other water on the planet.

Urban Rivers as "system of systems"

All of us, I think, believe that urban rivers are pretty special places. All of us who have spent any time at all working or thinking about the preservation of urban rivers also know that the work of establishing sustainability on urban rivers is really challenging. "Challenging" here is the modern euphemism for "maybe too hard to do, and certainly involving more struggle and effort than I bargained for, but I have to try anyway."

Anyway, I want to suggest here a framework for thinking about the challenge of sustainability on urban rivers. We won't have the "answer' today, and may not have it for a while yet, but I think the terms and framework offered here can structure our thoughts moving forward.

I have found it helpful to think of the urban river as a system of systems. In brief, and with apologies for necessary distortion through brevity, these systems are:

  • ·   hydrologic systems, what's in and on the water, both chemically and biologically. This category also refers, in my mind at least, to the actual ways the water meets other surfaces, scouring the bed of the river, carrying sediments, and so forth.
  • ·   terrestrial ecosystems, the plant and animal communities that live along the river and depend upon it for their health and survival. In many respects, these systems function in ways best understood by specialists; what the public sees as a lush green forest is full of invasive plant species that don't support a diverse community as well as they should.
  • ·   human systems, the roads and streets, settlements, public spaces and all of the other physical space that we shape in order to live along the river. Too often, we see these systems only as intrusions upon the others, a point of view that may ultimately be self-defeating. Nevertheless, poorly designed and planned human systems can and do cause great harm to hydrologic and terrestrial systems.

It's pretty easy to say that all three of these need to be in balance. But what is that "balance," and who decides? Is it even possible to design a community of humans that doesn't damage the communities of plants, animals, and the river that supports us all? 

I believe that it is, and will be posting further ideas, research, projects and so forth over the weeks and months ahead. In doing so, I will be reporting as well as I can, as specifically as I can, about a whole range of topics in which the expertise is led by others. No single person can know all of the science, policy, design, and programming/engagement efforts that make up this subject. As always, I invite comments that contribute to the effort and look forward to hearing from you.

  The opinions expressed in this blog are those of the author(s) and not necessarily
  of the Institute on the Environment/University of Minnesota.