On October 18th, 1972, President Nixon signed into law a number of amendments to the Federal Water Pollution Control Act, creating the modern Clean Water Act.

“The Federal Water Pollution Control Act Amendments of 1972 — the modern Clean Water Act — established a national commitment to restore and maintain the chemical, physical, and biological integrity of the nation’s waters. The Clean Water Act has been instrumental in improving the health of rivers, lakes, and coastal waters. It has stopped billions of pounds of pollution from fouling the water, and dramatically increased the number of waterways that are safe for swimming and fishing.”

from “A Brief History of the Clean Water Act”, from PBS’s NOW

President Nixon Signs the Clean Water Act Amendments in 1972.