Rivers and streams in the Cape Fear River Basin in eastern North Carolina rank No. 1 in amounts of No. 2.
A new report from the state Division of Water Resources shows that the waterways in this basin have elevated amounts of fecal coliform — bacteria from animal and/or human waste. That’s to be expected, since the 9,164-square-mile basin includes areas packed with industrialized hog farms.
From July 2015 to June 2016, five of the state’s 17 river basins contain high amounts of fecal coliform: Cape Fear (down east), Catawba (west near Hickory), Hiwassee (far southwest), Broad River (west of Charlotte) and White Oak (down east).
Those waterways recorded averages of more than 400 “colony forming units” — aka bacteria — per 100 milliliters of liquid, which is equivalent to about 6 tablespoons.
The results are based on the state’s random ambient monitoring program. Under that program, DEQ collects water samples at individual stations in the basins over time — months or even years.
Even though the amount of phosphorus has decreased by 21 percent from 2014, the waterways in the Yadkin basin still had the highest levels of it in the state. The Catawba, White Oak, Cape Fear, Neuse and Roanoake basins also have high average concentrations of phosphorus. The Yadkin basin also ranked first in nitrogen and turbidity.
Phosphorus and nitrogen are also called nutrients. (For algae, high amounts are the equivalent of a vitamin-packed all-you-can-eat buffet.) These nutrients enter the water fertilizers from lawns and fields and animal waste from city parks and rural farms.
There is no current state surface water standard for phosphorus, which contributes to algae blooms and other water quality issues. However, the state is reviewing the criteria to possibly establish a standard.
Turbidity essentially measures the cloudiness of the water, which becomes more opaque when dirt and other materials enter it. Pathogens can hang out on these particles, feeding on them without having to leave the house. People can become ill after drinking or inhaling water containing these pathogens.
What we don’t know about the health of the waterways in river basins is as troubling as what we do know. For example, the state doesn’t routinely test for emerging contaminants like the brain-eating amoeba, formally known as Naegleria fowleri; nor are there federal or state standards for it.
And as several EMC members pointed out, the basin data that was collected doesn’t show the source of the pollution. “The use of this report will be tied to its usefulness,” said EMC Chairman Steven Rowlan.
Because of funding and staff cuts, only waters designated as Class V were sampled. Class V waters can be used by industry to supply their employees with drinking water, but they are subject to fewer regulations than Class I, which, DEQ says, “offer the maximum protection for users.”
Sampling Class I or II waters, for example, could better assess the threats to drinking water supplies.
But it’s not feasible to expand the sampling, McMillan said, “until there is more money.”