Dear EarthTalk: What’s being done to clean up hog farming operations in places like Iowa and North Carolina and others where the industry is quite large? I’ve heard horrific stories about man-made "lagoons" of animal waste spilling into and fouling rivers and groundwater and the like.
—John Schmid, Fremont, California
Hog farming has always been a messy business, but surging demand for pork in recent years has exacerbated an already foul problem: dealing with the continual production of the bodily waste of thousands of animals. Pigs are kept in tight quarters and their waste is channeled into huge open-air lagoon pits and sprayfields. The lagoons can rupture during heavy rains, unleashing a torrent of bacteria- and virus-laden feces and urine into nearby groundwater, lakes and streams. Likewise, sprayfields, where some farmers discard animal waste by spraying it over otherwise unused land, can pollute surrounding waterways and contaminate drinking water. Another side effect is air pollution: The lagoons and sprayfields emit methane (a leading greenhouse gas) and ammonia (a respiratory irritant) into the atmosphere, the foul odors sullying the air quality—and neighbors" quality of life—for miles around.
The problem has been especially bad in North Carolina, where the number of hogs raised has gone up fourfold in the last two decades—hog farmers there now raise and slaughter some 10 million hogs a year. In 1995, a hog waste lagoon overflow at Ocean View Farms in North Carolina sent 20 million gallons of hog waste into the New River, causing massive fish kills and contaminating drinking water in several neighboring communities. And the torrential rains and flooding that accompanied 1999’s Hurricane Floyd wreaked havoc on hog farm waste lagoons and surrounding ecosystems across North Carolina.