Assessing dangers from animal waste, human sewage, coal ash, petroleum and every other unwelcome thing Hurricane Matthew washed into North Carolina waterways.
By Catherine Clabby
Along with 27 deaths, destruction in 37 counties and disruption of normal life, Hurricane Matthew floods flushed lots of uncertainty into eastern North Carolina.
While all rivers in that battered region were expected to be below flood stage this week, state officials are still assessing the health hazards Matthew’s sometimes record-breaking flooding deposited in rivers and streams.
Risks posed by animal and human waste, coal ash, fuel leaks and more are still be to gauged in the Neuse, Pamlico and Cape Fear rivers and tributaries.
Inland, it’s not yet clear how many overrun drinking water wells remain unsafe. In coastal waters, risks to shellfish beds are not yet fully understood.
If that was not enough, there is new uncertainty—thanks to rising temperatures producing climate change—about how bad the next flooding disaster could be. Evidence is growing that big storms are, on average, likely to bring more rain than they used to.
“We can say with very high level of confidence that these kind of flood events will be worse in the future,” said Ken Kunkel, a federal climate scientist who has co-authored a recent federal report on climate trends in the Southeastern U.S.
Danger from tainted water?
News reports during the worst of the flooding were crowded with dramatic aerial photos and videos of flood water inundating hog and poultry farms, indicators that waste laced with contaminants escaped into waterways that feed public drinking water systems or wash over shellfish beds downstream.
The Department of Environmental Quality is attempting to quantify what is where, with sampling at 30 locations on waterways near where flooding reached hog lagoons, wastewater plants, and towns and cities, said Marla Sink, a spokesperson for DEQ’s water resources division.
Fourteen commercial-scale hog and poultry farms were flooded in this disaster in Pender, Wayne, Jones, Greene, Bladen, Sampson and Craven counties. Two waste lagoons breached at one farm location in Craven County, Sink said.
Waters near them will be tested for ammonia, nitrogen, phosphorus and the fecal coliform bacteria known to be present in hog waste, among other contaminants.
Waste from concentrated animal feeding operations (CAFOs), where sizable numbers of animals eat animal feed rather than forage, may carry bacteria and parasites that can cause food and waterborne illnesses. Some waste may also be laced with metals, such as the arsenic and lead used in some poultry feed to stimulate animal growth, said Scott Marlow, head of Rural Advancement Foundation International – USA.
But it is not clear whether any of that exists in a high enough concentration in North Carolina waters to cause harm.
“The dose makes the poison, right?” Marlow said. “This is not your septic system backing up in a basement. Astronomical amounts of water passed through eastern North Carolina these past weeks. Will this stuff get diluted, yes. How much, I don’t know.”
Much less attention has been paid to the large amount of untreated wastewater, which includes human waste, that Matthew and the floods spilled into waterways. Sewage can also carry disease-causing pathogens, with viruses, bacteria and protozoa included. Kids, elderly people and anyone with a suppressed immune system are particularly vulnerable to stomach and respiratory infections and other illnesses these pathogens can cause.
DEQ knows of 235 storm-related spills of sewage/wastewater related to Matthew, Sink said. As of Monday, DEQ had recorded reports of more than 62 million gallons of sanitary sewer overflow escaping from water treatment systems into surface waters in a database. Not all data regarding the spills had yet been entered but extreme weather, pump station failures and power outages were cited as causes of spills.
Good news, bad news
Many animals died on densely populated commercial farms during flooding created by Matthew’s rains; an estimated 1.7 million chickens, 112,000 turkeys, and 2,800 swine, said Brian Long, public affairs director for the state Department of Agriculture and Consumer Services. Most carcasses appear to have been contained on those farms, Long said.
“We don’t know whether backyard or pasture-raised farm animals washed into streams or rivers,” Long said.
Dead animals carcasses have to be disposed of carefully so that they don’t pose health hazards, Long said. Dead swine have been sent either to landfills or rendering plants. Nearly all of the dead birds will be composted on farms with a fraction sent to landfills and rendering facilities too.
“Composting is the preferred method. It reduces leaching of farm waste, reduces pest and disease issues and prevents odor issues,” said Long, whose department is using a $6 million grant from FEMA to buy sawdust and other wood products that contain carbon needed for this large composting job.
Unanswered questions persist about coal ash. DEQ and Duke Energy are evaluating whether more than a minimal amount of ash and cenospheres, tiny, inert spheres produced during coal combustion, spilled from inactive coal ash impoundments at its Goldsboro-based H.F. Lee facility into the Neuse River in Wayne County during flooding.
The environmental group Waterkeeper Alliance has accused Duke Energy, which had 1.5 million customers without power at the height of the disaster, of downplaying potential risks from spills at the Lee site. Appalachian State University scientists have detected heavy metals, including antimony and cobalt, attaches to microscopic cenospheres collected near the site, the Alliance has reported.
Testing of water samples taken near Duke Energy will look for metals, Sink, the DEQ spokesperson, said.
Matthew’s floods released unknown amounts of petroleum too into open waterways. The largest spill reported to DEQ as of last week was 2,000 gallons of diesel from a damaged tanker truck trapped on flooded Route 55 that seeped fuel into flood waters in Seven Springs.
After two major flooding events within 17 years, one caused by Hurricane Floyd in 1999 and now Matthew, it may be time to move poultry farms out of floodplains, said Mike Williams, director of North Carolina State University’s Prestage Department of Poultry Science.
Such an effort has already put a number of hog lagoons out of the way of floodwaters, he noted. The state’s Clean Water Management Trust Fund spent $18.7 million to buyout 42 swine operations from the floodplain and decommission 103 waste lagoons after Floyd. The 1999 storm did more damage to hog farms, flooding 50 lagoons and causing six to breach.
Williams stressed that he supports the growth of poultry farming, now the number one agricultural industry in the state, in recent years in North Carolina. And, unlike some environmentalists, he doesn’t see an environmental risk from poultry waste during floods. But he is concluding that the economic costs, the effort required to compost carcasses and personal impacts on farmers after big floods may just be too expensive to repeat.
“As a scientist I feel ethically obligated to say that with climate change we can anticipate that this is going to happen again,” Williams said of the flooding. “We need to take a hard look at where some are located.”
When such storms do happen again, even heavier rains could pummel this state and other parts of the Southeast in coming years, Kunkel said.
Rising global temperatures allow the atmosphere to hold more water vapor, which can increase the amount of rain released by storms. As a result extreme rains, on average, are becoming more extreme, said Kunkel, a N.C. State University research scientist based at the National Oceanic and Atmospheric Administration’s Cooperative Institute for Climate and Satellites in Asheville.
In places where a rain event that was once a 100-year storm or a 500-year storm (meaning a storm of that severity had a 1-in-100 or a 1-in-500 chance of occurring in a given year) will be less rare in the future if global temperatures continue to rise, he said.
Kunkel and colleagues are working on a project for the U.S. Department of Defense trying to revise such predicted risks in a warming world. He knows many other entities, including state and local governments, will need the same thing for planning land development.