to do so. Comprehensive federal regulations for water supply and sanitation were introduced in the 1970s, in reaction to increased public awareness of environmental degradation nationwide. In 1970 EPA was established by the Richard Nixon administration, and authority for managing various environmental programs was transferred to the new agency. In 1972, Congress passed the Clean Water Act (CWA), requiring industrial plants and municipal sewage plants to improve their waste treatment practices in order to limit the effect of contaminants on freshwater sources. In 1974, the Safe Drinking Water Act was adopted for the regulation of public water systems. It was motivated by a resurgence in concern about the safety of drinking water due to breakthroughs in chemistry that revealed organic chemicals in water that were tentatively linked with cancer. This law specified a number of contaminants that must be closely monitored and reported to residents should they exceed the maximum contaminant levels (MCLs) allowed. EPA was charged with creating standards for drinking water for all public systems, defined as those that served more than 25 customers or 15 service connections. The new law required federal and state governments to closely monitor local drinking water utilities for safety and compliance with federal standards. The CWA set the unprecedented goal of eliminating all water pollution by 1985 and authorized massive expenditures of $24.6 billion in research and construction grants for municipal sewage treatment. The funds initially provided an incentive to build centralized wastewater collection and treatment infrastructure for municipalities, instead of decentralized systems. However, the 1977 amendments to the CWA required communities to consider alternatives to the conventional centralized sewer systems, and financial assistance was made available for such alternatives. In the mid-1990s decentralized systems served approximately 25 percent of the U.S. population, and approximately 37 percent of new housing developments. The vast majority of municipal wastewater in the U.S. is treated to the national secondary treatment standard or better. There have been a few disagreements between EPA and some local governments about the appropriate level of treatment, with the former arguing for more stringent standards. For example, in the late 1980s, the city of San Diego and EPA were involved in a legal dispute over the requirement to treat sewage at the Point Loma Wastewater Treatment Plant to secondary treatment standards. The city prevailed, saying that it saved ratepayers an estimated $3 billion and that process had proved successful in maintaining