North Carolina is known as the hog heaven. It’s one of the most prominent swine producers in the U.S., with pigs almost outnumbering the state’s human population.
This pork production ends up in millions of tons of pig waste that must be amassed, stored, and treated in massive outdoor waste lagoons.
These huge brownish-pink ponds have multiplied in the past four decades as demand rises. North Carolina swine farmers have shifted from raising pigs on large tracts of free land to concentrated animal feeding operations (CAFOs). Waste lagoons are essential as receptacles of the waste products, where microbes decompose organic material so some of it can be utilized to spray on crops as a nutrient-rich fertilizer.
Nonetheless, swine lagoons have some downsides, as well. For instance, excess nutrients from the waste in nitrogen and phosphorus accumulate in lagoons and upend the biological equilibrium of local soils, groundwater, and surface water.
Sighting the telltale pink or brown geometric shapes of the waste lagoons is similar to a dirty game of “Where’s Waldo.” So far, Montefiore and her colleagues have utilized Google Earth Pro’s database to observe 3,405 waste lagoons spread along North Carolina’s coastal plain.
“The satellite data reveal specific trends in lagoon construction dating back to the industrialization of pig farms in the state during the 1980s, past the moratorium on further construction of swine lots in 1997 and onward to more modern times, “the researchers explained.