The study began with an analysis of Federal statutes concerning water pollution control and enforcement efforts stemming from these laws, as well as relations between Federal and State governments concerning pollution control efforts. A direct linear relationship between the wording of the laws, administrative organization, resources, enforcement effort, and impact on the environment was initially hypothsized. Measures were developed for strictness of State antipollution laws, policy outputs by enforcement agencies and impact on the water quality. Comparisons were made among the States by using rank order correlation coefficients and cross-tabulations of grouped data, but the model's accuracy was not conclusively demonstrated. It was concluded that no impact on water quality was yet discernible either because of lack of suffiecient evidence or the general level of enforcement. Physical, political, and economic variables in the States' environments were compared with strength of enforcement efforts. The magnitude of the physical problem which different States face, the interest which State legislatures have exhibited in the problem of water pollution control, and the relative strenght of various interest groups in the State help to explain some of the differences in degree of enforcement among States. Some evidence demonstrates that different groups receive different types of satisfaction from the political system in this public policy area. Footnotes, data tables, flow charts, and a bibliography of approximately 270 references are included. (Author abstract modified)