Ecological regions versus hydrologic units: Frameworks for managing water quality

Excerpt

IN the mid-1970s, a flurry of research and assessment activity began on nonpoint-source pollution. Much of this activity was driven by legislative requirements, particularly Section 208 of the Clean Water Act, which required states to identify nonpoint sources of pollution and develop feasible methods to control these sources. Unfortunately, response to the law was piecemeal. Individual states used a variety of different methods to research and assess water quality problems, and most lacked a logical and useful spatial (geographical) framework to put the results into a meaningful perspective. State water quality assessments often used drainage basins or hydrologic units, and federal assessments used similar units or even political boundaries. Similarly, best-management-practice recommendations were commonly made for political units, drainage basins, or hydrologic units.

It soon became obvious that extrapolating results of nonpoint-source pollution research was difficult, and efforts to illustrate the extent of the problems for states and the nation were fuzzy, if not grossly distorted. As one review pointed out in 1985, the net effect of 10 years of nonpoint-source pollutant characterization and hundreds of “208” plans was hard to document (35). Chesters and Schierow (2) observed that, in spite of …