The Washington Post has published an insightful article discussing the huge increase in water pollution caused by livestock and poultry manure over the last few decades.
Yes, manure. About 2.7 trillion pounds of dung is generated by America's farm animals every year. That's about ten times the total amount of fecal material generated by all the humans in the country during a year.
The concentration of farming into gigantic, centralized operations has led to production of far more livestock and chicken dung than can easily or, in some cases, economically be used to fertilize crops. That waste is stored in piles or lagoons, from which it leaches into rivers and streams. According to a 2001 report from the U.S. Department of Agriculture that surplus accounts for 60 percent of all the nitrogen and 70 percent of all the phosphorus stored in the country's agricultural manure.
That nitrogen and phosphorus causes algal blooms and eutrophication in lakes and streams and is largely responsible for the creation of "dead" zones in the Gulf of Mexico.
Despite changes to it in 2002 and 2005 intended to address the problem of stored animal waste, the Clean Water Act is not currently a reliable tool for preventing the toxic pollution that is often caused by these byproducts of modern large-scale agriculture.
It is fine, as far as it goes, to require those who operate "combined feeding operations" to obtain a National Pollution Discharge Elimination System permit under the Clean Water Act. The problem is that mandate is not enough to stop the continued concentration of livestock into living spaces that are too small. The solution must involve giving farmers and agriculture companies an incentive to "spread the animals out." With less accumulation of manure in few places it will be more realistic to expect that the water pollution impacts of animal waste can be effectively addressed.
Of course, agricultural manure production on an industrial scale does not only affect water quality. It also contributes significantly to air pollution and global warming, as stored waste emits a variety of gases. They include methane, hydrogen sulfide, ammonia and, of course, carbon dioxide.
Therefore, this is an issue that must also be addressed in any effective greenhouse gas reduction strategy.
The public health dictates more attention to the problem, too. Livestock and poultry waste often contains zoonotic pathogens that are dangerous to humans, as well as pharmaceutical compounds such as hormones and antibiotics.
Unfortunately, there does not appear to be much focus on this problem in Congress. And EPA has not been enthusiastic even about making sure the public is aware of it. In 2008 the agency exempted animal waste air pollution discharges from reporting obligations under two federal environmental laws.
Perhaps, since "change" is a theme that apparently continues to resonate with the American public, it's time for leaders in Washington, D.C. to think hard about how to counteract this growing and serious environmental and public health threat.