The Clean Water Act has been a success in many ways. The discharge of pollutants from both industrial and municipal point sources has plummeted, the loss of wetlands has been cut decisively, and water quality has improved broadly across the entire nation. Despite all of that progress, many of our waters remain impaired. The primary reason for this lies in the failure of the Clean Water Act to effectively tackle two significant sources of water pollution: nonpoint source pollution (diffuse runoff from, for example, fields and logging operations) and hydrologic modifications (such as water withdrawals and dams).
In contrast to the Act’s approach to point source discharges and the loss of wetlands, Congress left control of both nonpoint source pollution and hydrological modifications primarily in state hands. While some states have responded well to the challenge, most have not been up to the task. New approaches are needed to deal more effectively and more comprehensively with both problems, the magnitude of which is staggering: over 40,000 nonpoint source-impaired waters and thousands of flow-impaired water bodies.
Climate change will exacerbate both problems. Heavier rainfall events have been increasingly common all across the nation, and this trend will likely intensify in the future. In places like the Northeast and Midwest, where this effect is expected to be most pronounced, the effect on water quality will be profound. More intense storms will produce greater erosion and stormwater runoff, resulting in more nonpoint source pollution. In addition, hotter and drier conditions in a number of other regions, especially the Southwest, will place greater strains on stream flows, wreaking increasing damage to aquatic ecosystems as well as threatening the adequacy of water resources for human use.
Crafting a more effective federal-state partnership to combat both problems has proven impossible for over 40 years. Many states and their allies in Congress have resisted such efforts, citing traditional state interests over land use and water allocations. The ...