In this article, I compare the efforts to protect two transboundary watersheds that are home to some of the largest industrial areas in the world: the Great Lakes basin in North America and the Rhine river in Western Europe. Specifically, I show that the industrial discharges into the Great Lakes have been more toxic than the releases into the Rhine. This is puzzling as the laws and international agreements pertaining to the Great Lakes have been more stringent than those concerning the Rhine. I solve this puzzle in three steps. First, I show that the many voluntary investments in water protection by companies along the Rhine have outdone the considerable efforts that the U.S. laws have required of Great Lakes corporations. Thereafter, I argue that these different inclinations to invest in water protection have sprung from two alternative modes of conducting environmental politics: an adversarial one in the Great Lakes basin and a more consensual one in the Rhine valley. Last, I use an historical-institutional approach to show which institutional differences (at both the domestic and international levels) have led to the emergence of these different modes of conducting environmental politics in the two basins.
