When prompted to consider water pollution, most people envision classic point sources: the corroded factory pipe pouring green sludge into a creek, the municipal waste treatment plant pumping stormwater runoff into an estuary, the oil behemoth's offshore well spewing millions of barrels of crude. But when I don my Water Pollution Contemplation Cap, I inevitably envision industrial livestock facilities.
Also known as concentrated animal feeding operations (CAFOs) or factory farms, these facilities raise thousands (or in some cases, hundreds of thousands) of animals in confined conditions without access to pasture. Unfortunately, factory farms currently produce the vast majority of meat, eggs and dairy in the US. Unbeknown to most of us who don't have the misfortune of living nearby, they're also big-time polluters.
The fundamental cause of all this pollution is simply that industrial livestock operations confine too many animals in one place. As a result, they produce a tremendous amount of waste - and by waste, I don't mean a little bit of old bedding hay and some leftover feed, I mean urine and feces - hundreds of thousands of tons of urine and feces. Indeed, industrial livestock operations often produce as much excrement as entire human cities. But while municipalities process human waste at sewage treatment plants, factory farms typically embrace a decidedly lower-tech waste management strategy: they just shove all the manure into big open pits called manure lagoons.
As anyone who's graced the confines of a well-used Porta-Potty on a hot summer day can surely attest, the uncovered-pile-of-excrement waste management technique gets pretty gross pretty fast. And when the pile of excrement fills a hole that's several acres large, the situation becomes downright dangerous. Of course, this setup emits a host of hazardous air pollutants known to sicken workers and anyone living in nearby communities. And oh yeah, factory farms generate greenhouse gases like they're trying to outpace the transportation sector. But we'll save discussion of all things ambient for another Blog Action Day.
Turns out that manure lagoons are prone to leaks, which allow pollutants to seep into groundwater. They can also overflow during storms or when there's a mechanical problem with a pump or pipe. And every so often, a sidewall will collapse. In all cases, manure ends up being washed into surface waters, or seeping into groundwater.
But even when manure lagoons function properly, water pollution is commonplace. Since livestock continually produce waste, lagoons need to be periodically emptied. Factory farms handle this situation by sucking out the sludge and applying it to surrounding land. Unfortunately, since there's so much waste, industrial producers often over-apply it, ultimately causing manure to be washed into ground and surface waters.
In two words, the pollutants. Here're the big ones:
Nutrients - primarily nitrogen and phosphorous; these pollutants induce eutrophication. Think back to high school biology: excess nutrients cause algal growth, which blocks light, killing underwater plants; then the algae die and decompose, which reduces the amount of dissolved oxygen in the water, ultimately killing aquatic life and creating dead zones (see Gulf of Mexico, Chesapeake Bay or any waterway next to a CAFO). Nutrient pollution can also cause growth of the highly toxic alga, Pfiesteria piscicida (think bleeding sores on fish and neurological damage to humans).
Pathogens - manure is lousy with these pesky microorganisms (a few big players: Campylobacter Cryptosporidium, E. coli and Salmonella). When livestock feces gets in our food, people can get sick. Same thing happens when livestock feces gets in our water. But unlike food, water can't be recalled. And in addition to consuming it, people use water for things like bathing, swimming and fishing.
Antibiotics - factory farms administer this stuff with reckless abandon in order to compensate for the squalid conditions in which they raise livestock. Thing is, 25 to 75 percent of antibiotics pass into animal manure unchanged - so if you leave a few million gallons of CAFO waste sitting around in an open pit, you create a giant Petri dish perfectly suited to induce the proliferation of anitibiotic-resistant bacteria. When the manure enters water, these bacteria go with it.
Heavy Metals - Nope, not the kind peddled by these guys. The kind that poisons people. Factory farms add traces of heavy metals to livestock feed in order to boost growth rates, but some of it passes into the manure - and when waste from millions of animals is collected in one place, the metals eventually accumulate, contaminate soil and can leach into groundwater. Think I'm making this up? Note the rate of arsenic contamination in the Delmarva Peninsula, where poultry factories raise more than half a billion broilers per year.
Other Nasty Stuff - Hormones (they're administered to livestock, pass into manure, end up in water and impair the reproductive systems of fish and other aquatic species). Ammonia (toxic to fish and can be converted to nitrates, which can contaminate drinking water and sicken humans). Organic matter (bedding material, feed, hair, feathers, dust, etc. - this decomposes in water, further reducing oxygen levels and killing aquatic life).
In stark contrast to the clean, bucolic imagery printed on milk cartons and meat packages, industrial livestock operations have always been filthy polluters - and as a result of Big Ag's tremendous political clout and a general lack of public awareness about their impacts, they've always gotten away with it. Regulation of industrial livestock facilities has never been sufficiently stringent - and enforcement of existing rules is notoriously lax.
But as much as I love to end posts with a hearty dose of doom and gloom, in this case, I'll bust out the optimism and mention Illinois. At the end of September, the Obama administration demanded that the IL EPA start enforcing the environmental regulations with which factory farms are supposed to comply, or else relinquish regulatory oversight to the US EPA. Although this may not sound particularly remarkable (environmental regulations are supposed to be enforced, right?), it's actually an unprecedented step toward cracking down on these chronic polluters. We're hoping the trend will continue. In the meantime, don't go swimming near any CAFOs.