By Michelle Werts

Credit: Fred Hsu/Flickr

Today marks the 40th anniversary of the Clean Water Act (CWA), which is the federal law governing water pollution in the U.S. The enactment of this act was fraught with peril, as it was passed by the Senate in November 1971 and by the House in March 1972 only to be vetoed by President Richard Nixon on Oct. 17, 1972. A day later, both the Senate and House would override Nixon’s veto, officially establishing CWA as the law of the land for protecting the integrity of our nation’s waterways. For the last 40 years, CWA has made significant headway in the fight against water pollution, but sadly, nearly half of all rivers, lakes and streams in the U.S. are still not swimmable or fishable.

Much of the CWA’s success has been in curtailing what’s known as point-source pollution, which is defined by the Environmental Protection Agency (EPA) as “any single identifiable source of pollution from which pollutants are discharged, such as a pipe, ditch, ship or factory smokestack.” By setting up regulations on common point source polluters like factories and sewage treatment plants, water pollution from those sources has been greatly reduced. However, there’s still the issue of nonpoint-source pollution.

Nonpoint-source pollution has the wonky definition of anything not defined as point source. Basically, this amounts to pollution that is a result of water running over polluted land during snow melts or rainstorms. Nonpoint source pollution often includes fertilizers, herbicides, insecticides, oil, grease and other toxic chemicals. In the past 30 years, there has been a threefold increase in nitrogen pollution from nonpoint agricultural sources entering the Gulf of Mexico from the Mississippi River and its tributaries.

Therefore, as the CWA moves into its next 40 years, American Forests is encouraging its governing body, the EPA, and the U.S. Department of Agriculture (USDA) to develop plans and programs to address the nonpoint-source problem, especially because forests can play a crucial role. Researchers have found that for every 10 percent increase in forest cover in the source watershed, treatment and chemical costs decreased by approximately 20 percent.

Lewiston-Auburn, Maine
Lewiston-Auburn, Maine. (Left) Documerica photo by Charles Steinhacker from June 1973: The Androscoggin River flows between Lewiston (eastern shore) and Auburn (western shore). Lewiston is the state’s foremost textile center. (Right) Same location in October 2012. Photo by Munroe Graham.