Portland Project Combines Flood Storage, Habitat Improvements

摘要

Historically, efforts to control flooding have often come at the expense of ecological systems and the wildlife that depend on them. Johnson Creek, which flows through Portland, Oregon, offers a case in point. During the 1930s the federal Works Progress Administration (later the Work Projects Administration) subjected the lower 15 mi (24 km) of the stream to extensive rock lining, channel deepening, and straightening, thereby eliminating most of the habitat used by salmon and other fish that inhabit the waterway. Despite these modifications, flood damage continued. In fact, the channel floods more frequently today, as development within the surrounding watershed has increased the quantity of runoff and the rate at which it enters the stream after storms.