Fields and Streams: Stream Restoration, Neoliberalism, and the Future of Environmental Science

CHAPTER 2. Stream Restoration and Natural Channel Design

18 chapter two Stream Restoration and Natural Channel Design The Rosgen Wars are deeply substantive, so analyzing them requires a firm grasp on the basics of how streams work and why they are restored. Thus I offer here a brief primer on streams, why they have become degraded, what people hope to accomplish through stream restoration, and who is involved in the restoration process. streams and restoration Terrestrial restoration, particularly of forests and prairies, may be the oldest form of ecological restoration in the United States (Egan 1990; Hall 2005), and wetlands restoration may be the biggest market (Environmental Law Institute 2007), but, judging by the numbers of grassroots organizations, stream restoration receives the most public attention. According to the us Environmental Protection Agency, as of 2010 there were more than 2,600 adopt-a-watershed groups nationwide, the vast majority of which focused primarily on fluvial systems.1 This number is orders of magnitude higher than for other types of restoration (tables 2.1 and 2.2). Even assuming errors and inaccuracies in these data, stream restoration clearly holds a special place in the American restoration movement. So why all this enthusiasm? What do rivers and streams (or fluvial systems, in more formal terms) do that so many people find so compelling? what rivers and streams do Every raindrop, snowflake, or hailstone that hits the ground (and is not lost to evaporation or transpiration from plants) eventually ends up in a fluvial system , flowing across the landscape and at last to the sea. With that water comes table 2.1. grassroots watershed restoration groups by state state watershed obviously percent groups stream-focused of total Arkansas 15 14 93 California 222 154 69 Georgia 55 52 95 Kentucky 260 258 99 New Jersey 43 29 67 Ohio 130 119 92 Tennessee 57 49 86 Virginia 38 28 74 805 689 86 Sources: Arkansas Watershed Advisory Group, http://www.awag.org/groups.html#able, accessed July 20, 2010; Institute for Computational Earth Systems Science at uc Santa Barbara, http://www.icess.ucsb.edu/~brenmail/wsg/att-0053/01-Watershed_Groups_in _California.html, accessed July 19, 2010; Georgia River Network, http://www.garivers.org /resources/directory.html; Kentucky Water Watch Groups, http://www.state.ky.us/nrepc /water/wwgroups.htm, accessed July 20, 2010; New Jersey Agricultural Experiment Station, Rutgers, http://njwrri.rutgers.edu/watershed_orgs.htm, accessed July 19, 2010; Ohio Watershed Network at the Ohio State University, http://ohiowatersheds.osu.edu/groups /wgp_all.php, accessed July 19, 2010; Waterkeeper!, http://frank.mtsu.edu/~waterwks /WatershedGroups3.htm, accessed July 19, 2010; private source, http://www.sklarew.com /vaflyfish/conserv/, accessed July 19, 2010. table 2.2. web data on prairie restoration and advocacy groups state number of prairie groups Illinois 6 Iowa 2 Kansas 2 Missouri 3 Nebraska 1 Ohio 2 Wisconsin 4 Source: The data were compiled through a web search for prairie organizations in the United States and in each of the states listed. 20 • chapter two sediment, as rivers and streams gradually erode even the most soaring peaks down to Appalachian-sized stubs and wash fragments of even the hardest rock across continents to form new sedimentary layers; at the landscape scale, rivers and streams are the great levelers. The key unit of analysis for a river or stream is not its immediate physical boundaries (as for wetlands or prairies) but its entire drainage basin: the geographic area within which all water drains to the same point. A drainage can range in size from a square meter in a suburban backyard to the four million square kilometers of the Amazon Basin, which is roughly the size of the continental United States. Drainage basins are defined topographically by drawing lines between the high points in the landscape: on this side of the mountain peak (or the mole hill), all water runs to one riparian system; on the other side, water drains to a different system. Regardless of scale, drainage basins typically take the form of a leaf or a tree: many small tributaries (each a drainage basin of its own) join together into a main stem, which in turn feeds into a larger basin, creating a fractal pattern. Organisms like aquatic insects, turtles, frogs, and fish migrate up the tributaries. Water, sediment, leaf litter, nutrients, insects, and fish ride the current down through the tributary structure and out the main stem; so, too, do mercury and arsenic from...