Hurricane Florence: North Carolina’s Pig Manure Lagoons Overflowed Extensively—But Didn’t Fail

September 19, 2018, 10:30 PM UTC

It’s an odd form of good news that the manure lagoons present throughout North Carolina have overflowed extensively into local water systems, with more to come, as a result of Hurricane Florence. But it’s only good news by contrast: In Hurricane Floyd in 1999, many lagoons not just overflowed their banks, but entirely failed, leading to massive outflows of untreated pig excrement and industrial farm waste. Predictions of modest damage made last week appear to have been proven accurate.

However, it’s still bad news for local water systems, already stressed by flooding that remains a danger from the recent hurricane. Power outrages and the massive amount of water overwhelm solid-waste management systems in urban areas, and the manure lagoon overflows add to that.

The waste entering the water system can produce algae blooms, render water unsuitable for drinking, and lead to die-offs of fish and both wild and farmed animals. This becomes a critical problem in farming communities.

The effluvia even in the best of time can affect human health, according to a study released online this week by Duke University. The study concludes that communities near hog lagoons suffer higher infant mortality and death from many causes, although the study says that a direct link hasn’t yet been established.

The North Carolina Department of Environmental Quality listed 110 hog pits at noon Wednesday that have overflowed or remain in danger of doing so, including 21 that have already discharged material. That’s triple the number from Monday, though some may be related to updated reporting to and by the agency.

Pig farms cluster in the eastern part of the state and in low-lying areas, which amplifies the risk and the environmental damage. Following Hurricane Floyd, the state bought up some farms in flood plains to prevent future outflows, and the state pork council said farmers beefed up lagoons to prevent recurrence. Hurricane Matthew in 2016, while less severe than Florence, resulted in only one breach and few overflows.

Across the state, hogs produce 10 billion gallons of manure each year, although the lagoons are seeded with bacteria that gradually turns waste into fertilizer.