Hog Farms No Threat to North Carolina Water Quality

Published March 1, 2004

Although there have always been hog farmers in North Carolina, the industry was fairly small until the mid-1980s. At that time, a major new hog slaughter plant opened in the state, and dozens of new confinement hog farms were set up to take advantage of eastern North Carolina’s low employment levels. As a result, hog farming in eastern North Carolina took off in the late 1980s and early ’90s.

The core of this hog farm expansion was located in Sampson and Duplin counties, two adjoining counties drained by two rivers–the Black and the Northeast Cape Fear. Between 1985 and 1995, the hog population in these two coastal watersheds increased tenfold, from 500,000 to 5.5 million animals. By 1997, this area accounted for 10 percent of the total U.S. swine inventory. (The balance of the state’s hog population, consisting of some two million animals, is scattered throughout the coastal plain.)

The rapid expansion of the hog population, the growing number of larger, integrated farms, and the central role of corporations alarmed environmentalists and social activists, who generally do not like either large corporations or large, intensive farming operations.

The controversy began in February 1995, when the Raleigh News & Observer ran a harsh, five-article series titled, “Boss Hog: North Carolina’s Pork Revolution.” The series detailed the explosive growth of the industry and questioned the environmental and social impacts of intensive hog production.

The top concern cited in the articles was the “9.5 million tons” of hog waste coming from the “megalopolis of seven million animals that live in metal confinement barns” in eastern North Carolina. The articles charged hog waste was polluting both groundwater and the state’s rivers and streams, harming the environment and posing a potential health threat to nearby residents. The “Boss Hog” series netted the News & Observer the 1996 Pulitzer Prize for Public Service Journalism.

No Harm to Water Quality

Yet there is still no evidence whatsoever that water quality has gotten worse in North Carolina. As researchers at Duke University’s Nicholas School of the Environment noted in research published in 2000:

“Eutrophication [of the Neuse River estuary] is believed to have worsened in recent years. … However, our results indicate that while nitrogen concentrations have not changed significantly, they may have declined slightly overall in the lower river and estuary in the last 22 years. Additionally, phosphorus concentrations have dropped considerably at all locations since the mid 1980s. [“Seasonal and long-term nutrient trend decomposition along a spatial gradient in the Neuse River watershed,” Environmental Science & Technology 34, 2000. Italics added.]

The Duke researchers speculated it was the improved water quality–the lower levels of phosphorus–that changed the critical ratio of nitrogen-to-phosphorus, leading to an increase in algal blooms in the Neuse estuary. This created the false impression that the water quality was declining. All too predictably, not a single North Carolina newspaper reported on this research or its implications in the debate over the environmental effects of hog farming.

There is, in fact, strong evidence that hog farms haven’t harmed water quality in the region. In early 2003, at the request of the Cape Fear River Assembly, the authors of this article set out to perform an extensive review of the historical water quality data in the Black and Northeast Cape Fear rivers (home to roughly 80 percent of the state’s hogs) for the period before and after the hog farm expansion.

When we called the Water Quality Division at the North Carolina Department of Environment and Natural Resources (DENR) to obtain the data, the director declined to release it to us. He claimed an analysis of that data already had been conducted as part of the DENR’s five-year environmental assessment published in 1999.

But the DENR’s report omitted water quality data for the Black and Northeast Cape Fear rivers completely. Instead, the report focused on “biological indicators” of aquatic health (such as inventories of fish) that implied a slight worsening of river conditions since the previous environmental assessment in 1994.

After major flooding and hurricanes in 1995-96, North Carolina received federal grants to clear fallen trees and woody debris clogging rivers and streams, to prevent future flooding. The DENR report admitted this factor made it impossible to blame hog farms for the decreases in biological indicators in the regional waters:

“Zealous pursuit of this goal often totally cleared all woody material from the stream, material that is a critical habitat for both fish and invertebrates. For some streams, heavy machinery was used along the banks. … It is difficult to separate out the effects of de-snagging in these streams from the potential impact of increased numbers of hog farms within the same area.” [Italics added.]

Data Exonerate Hog Farms

The 1999 DENR report included water quality data for other rivers within the Cape Fear basin … so why did the agency omit only the data for the two rivers draining the intensive hog farming areas? Why did the DENR instead rely on a flawed proxy of water quality? When we insisted on examining the data ourselves, the head of the Division of Water Quality at DENR refused to provide it. It wasn’t until legal action was threatened that we were provided the data.

The data clearly show the water quality within and downstream of the hog farming areas is as good now as it was before the hog industry expansion. Despite a tenfold increase in the hog populations, there has been no increase in nutrient concentrations, no reduction in dissolved oxygen levels, and no increase in sediment loads.

Incredibly, during nearly a decade of intense, acrimonious debate between environmental activists and hog farmers–whipped into a frenzy by articles like the News & Observer’s “Boss Hog” series–the DENR suppressed its own water quality data and failed to inform the public and policymakers of the real conditions of the rivers and streams in question.

In this way, the government of North Carolina effectively stole the great economic opportunity of hog farm expansion from some of its poorest citizens.

Bad News Sells

Our own report was not totally ignored by the media. The Wilmington Star-News ran a single article on the study, published before our report was even written. The headline to the story tells you everything you need to know about press coverage of the controversy: “Defense of Hog Farms Full of Holes, Scientist Says.”

The public is too often given only one-sided, simplistic, pessimistic versions of environmental realities by the news media, and even by government agencies and researchers.

Journalism has never been more important to our society … and, perhaps, never less adequate.

Dennis T. Avery is director, and Alex Avery is director of research and education, of the Hudson Institute’s Center for Global Food Issues. A longer version of this article originally appeared in the Fall 2003 issue of American Outlook, a publication of the Hudson Institute.

For more information …

See “North Carolina Hog Farming & Water Quality: Time Series Analysis Fails to Reveal Significant Impacts,” written by Alex Avery and released by the Hudson Institute. The 24-page report is available on the Web site of the Hudson Institute’s Center for Global Food Issues at http://www.cgfi.org/pdf/NCHogImpactReport.pdf.

A three-part series on hog farming appeared in the December 2003, January 2004, and February 2004 issues of Environment & Climate News, available on The Heartland Institute’s Web site at http://www.heartland.org/Publications.cfm?pblId=1.