Summary And Conclusions

The cleanup of the Willamette River has been accomplished because of overwhelming public support; strong commitment by federal, state, and local governments; comprehensive water quality studies that documented the extent of the problems; and the implementation of sound engineering proposals for controlling water pollution. Public pressure and responsive political leadership have resulted in the basinwide implementation of secondary treatment requirements with a minimum of legal actions needed to ensure compliance with the regulations. Water quality studies of the Willamette (e.g., Rickert, 1984; Rickert et al., 1976) have demonstrated the importance of the minimum requirement of secondary waste treatment for municipal and industrial dischargers, as well as the significance of background water quality and summer low-flow augmentation from USACE reservoirs, in achieving Oregon's water quality goals.

Vast improvements in the water quality of the Willamette River, facilitated by stringent regulatory controls, have led to remarkable improvements in the integrity of the river's biological communities. Of major importance, both recreationally and economically, is the continuing recovery of the fisheries. Salmon and steelhead on their migratory spawning runs are no longer precluded from reaching their spawning grounds in the Willamette River basin because of severely depressed or nonexistent concentrations of DO. Recreational anglers are once again able to enjoy pursuing these valuable gamefish as the fish make their way up the river to their spawning grounds. Another significant improvement is the return of viable populations of resident species of gamefish, including bass, catfish, perch, sturgeon, and crappies.

Although the severe water quality problems that have plagued the Willamette River in the past are clearly gone, there are still reasons for concern about the river's overall health (Tetra Tech, 1995). Until the continued presence of toxic contaminants in the water and sediments, the loads of suspended sediment and nutrients, and the alteration of the habitat can be abated, the overall ecological conditions of the Willamette River will continue to suffer.

For four decades, beginning in the 1920s, the Lower Willamette River near Portland, Oregon, was considered one of the most polluted urban-industrial rivers in the United States. Three decades after enactment of strict water pollution control regulations by the state of Oregon in the late 1960s and the federal Clean Water Act in 1972, the remarkable improvements in water quality and the ecological health of the river now provide important recreational and commercial benefits to the citizens of the Willamette valley. Salmon and steelhead fisheries, once blocked by dams without fish ladders and constrained by low dissolved oxygen conditions, are now sustained by migratory populations that can safely reach upriver spawning grounds. The local economies of major cities on the Willamette River are thriving, and upscale developments are attracted to riverfront locations by the aesthetics of a clean river that was once considered noxious with an unsightly riverfront. Although significant accomplishments have been made to improve water quality and ecological conditions in the Willamette River, continued investments are needed to address contemporary issues for continued restoration and maintenance of the river's ecological integrity. The designation of the Willamette River as an American Heritage River in 1998 recognizes both the significant environmental improvements that have been accomplished and the continuing need to address the key ecological issues identified in the 1990s. Nutrient enrichment, sediment loading, and the lingering presence of toxic chemicals in the river, sediment bed, and biota are ecological problems that remain. With cooperative efforts by state, local and federal agencies, they will be addressed in the early decades of the twenty-first century.

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