Annual Gallup polls over the past decade have consistently found the pollution of rivers, lakes, reservoirs and drinking water to be the environmental problems of greatest concern to Americans. Since passage of the Clean Water Act in 1972, considerable progress has been made in controlling pollution of the nation's freshwaters. However, most successes have been with point sources of water pollution, such as factories and municipal wastewater treatment plants. Much less progress has been made in controlling pollution from nonpoint sources, such as farms or roadways.
Given the continuing concern over nonpoint-source pollution, researchers at the Rocky Mountain Research Station sought to understand how the risk of water quality impairment from nonpoint sources varies across the nearly 3,700 fifth-level watersheds in the U.S. containing lands of the National Forest System (NFS). The risk was assessed based on comprehensive nationwide data sets for a series of watershed stressors and resources at risk.
Findings show that the non-NFS areas of the watersheds are consistently under much greater stress than the NFS parts, but that the resources-at-risk are more evenly spread across the NFS and non-NFS areas of the watersheds. Moreover, the results show that risk is unevenly spread across the NFS, with most units in the two eastern regions at higher risk than nearly all units in the western regions. The substantial difference in risk of impaired watershed condition on NFS as opposed to non-NFS lands offers strong evidence that ecosystem processes and the goods and services that flow from these processes are under reduced risk on public lands, even if those lands are managed for multiple uses. Given the increase in development of private lands that is expected as the U.S. population continues to grow, the difference in risk of impaired watershed condition between public and private lands is likely to grow, thus increasing the value of the protected lands.
This research offers a starting point for decisions on risk mitigation efforts, one that could be supplemented by locally-available data on additional indicators and by a comparison of the costs and benefits of mitigation options. This assessment also provides consistent data for others to use in national or regional watershed analyses.