Nearly three decades after enactment of the modern Clean Water Act (CWA), efforts to address the largest remaining source of water pollution—runoff and other types of aquatic ecosystem impairment from diffuse activities—remain elusive. Every two years, the U.S. Environmental Protection Agency (EPA) confirms in its biennial National Water Quality Inventory that nonpoint source water pollution, or "polluted runoff," causes the majority of water body impairment throughout the country. Despite periodic statutory amendments designed to turn this situation around, the numbers never seem to change very much. Polluted runoff from row crop agriculture, logging, grazing, development and other sources, along with other activities such as dams, water diversions and the like that significantly alter aquatic and riparian habitat, continue to impair both human and ecological uses of our rivers, lakes, and coastal waters. While significant amounts of money have been spent and substantial programs have been developed to address the problem, the nature and magnitude of the problem does not seem to have changed significantly.

The clearest explanation for this long-standing state of affairs is that, to succeed, environmental programs must be guided by some mechanism to ensure that whatever tools are chosen are used in ways that are likely to accomplish the task. This is true in particular for programs designed to address aggregate impairment from multiple and diverse sources: "The litany of past failures to plan and implement watershed programs suggests that these renewed efforts must be designed with more rigor and attention to pragmatic concerns such as specificity, accountability, and enforceability." This type of precise guiding force has been lacking for nonpoint source programs in particular, and watershed protection efforts in general. Indeed, some remain skeptical that this type of comprehensive control program can work effectively even if all of the necessary tools are in place: