|Detroit Dam, Marion County, Oregon, July 1990. Photo Bob Heims, U.S. Army Corps of Engineers.|
Scott Learn has a very interesting article in today's Oregonian about the negative impacts that Willamette River tributary dams are having on native salmon runs ("Getting salmon past daunting Willamette Basin dams could have a big price tag -- and a big payoff"). This is a clear example of unintended consequences resulting from large-scale infrastructure projects.
When the Willamette Valley Project was first being proposed and planned in the 1930s and 1940s, advocates asserted that the dams would bring a great many benefits. Impounding tributary waters would help modulate the seasonal flow of the Willamette River which would, in turn, decrease the likelihood of downstream floods. The dams would also facilitate reclamation, irrigation, hydroelectric power production, and navigation improvements. By storing water during the rainy months and metering its release during the dry months, Willamette Valley Project dams would modulate significant seasonal variations in the flow of the main stem, which would greatly help flush the river of industrial wastes and municipal sewage.
Historian William G. Robbins has found that by at least the late 1930s there was significant opposition to Willamette Valley Project dams (and also dams along the Columbia, Rogue, Umpqua, and Deschutes rivers) based upon the projected negative impacts these dams would have on anadromous fish runs. These opponents included commercial and sports fishing groups, Columbia River treaty tribes, and wildlife conservationists in groups such as the Izaak Walton League, including renowned naturalist William L. Finley. Robbins quotes U.S. Fish and Wildlife Service biologist Paul Needham's reference to these dams as "large-scale experiments" that did not sufficiently take the needs of fish into account. It certainly cannot be said that Willamette Valley Project planners were entirely unaware of the likelihood of harm to salmon runs.
As Scott Learn writes in his article, in terms of healthy native anadromous fish runs, the Willamette Valley Project has certainly been a failed experiment. In terms of pollution abatement and flood control, however, the experiment has been quite successful. Therein lies the conundrum: How might we achieve the goals of healthy fish runs, a cleaner river, and a low incidence of catastrophic floods? Whatever the specific answers turn out to be, my hunch is that it will take both a fundamental shift in cultural values & priorities and a significant financial investment to achieve such mutually beneficial ends.
 William G. Robbins, "The Willamette Valley Project of Oregon: A Study in the Political Economy of Water Resource Development," Pacific Historical Review 47:4 (Nov. 1978), 585-605; William G. Robbins, Landscapes of Conflict: The Oregon Story, 1940-2000 (Seattle: University of Washington Press, 2004), 47-76.
 For more on Willamette River pollution generally, see James V. Hillegas, "Working for the 'Working River': Willamette River Pollution, 1926-1962," MA thesis, Portland State University, 2009.
 Robbins, Landscapes of Conflict, 48-53.