Congress passed the Safe Drinking Water Act (SDWA) in 1974 and amended it in 1986 and 1996 to protect public health by regulating the nation's public drinking water supply. Under SDWA authority, the United States Environmental Protection Agency (EPA) establishes national health-based standards for drinking water that protect against a wide range of contaminants, and it provides national leadership in implementing a suite of programs designed to protect water supplies and ensure the sound operation of water systems. Drinking water standards set either enforceable maximum levels of individual contaminants in drinking water or required ways to treat water to remove contaminants. EPA, state governments, and water systems work together to make sure that these standards are met. The 1996 Amendments to SDWA, Section 1452, created the Drinking Water State Revolving Fund (DWSRF) program. The DWSRF is a multifaceted tool for states to use in achieving the public health protection objectives of SDWA. States operate their own DWSRF programs and receive annual capitalization grants from EPA which they use to support low-interest loans and other types of assistance to public water systems. Additional provisions also allow state DWSRF programs to target extra assistance to those communities with the greatest economic need.