The National Park Service has collected two samples of algae at the Buffalo National River that appear to indicate more types of algae in the river than previous sampling by another federal agency revealed.
In September, after tourists reported algae on a 30-mile stretch of the river from U.S. 65 to Spring Creek, the U.S. Geological Survey sampled algae and found it to be mostly harmless. The algae found was from the genus Oedogonium.
In October, Chuck Bitting, the natural resource program manager for the Buffalo National River, said he wanted to do more testing along that stretch.
Bitting, whose wife was one of several people who spotted algae while canoeing, had wanted to return to the area to ensure that none of the algae is a type commonly called blue-green algae that can be harmful to humans and wildlife.
Bitting said his team didn't find any blue-green algae but tested two samples that appeared to show algae from the genuses of Oedogonium, Spirogyra, and either Cladophora or Pithophora. Instead of sending the samples to the U.S. Geological Survey to be tested, Bitting and another researcher placed the samples under a microscope, took pictures and sent the magnified images to the agency, which determined what algae they were looking at, he said.
Spirogyra, Cladophora and Pithophora are also known as green algae, which is not as harmful as blue-green algae but can depress oxygen levels for fish in the water at night, Bitting said. Green algae also produces oxygen during the day, but Bitting said he didn't know if the algae produces more oxygen than it consumes. At the least, he said, algae is an obstruction for fish.
Bitting said the algae could be caused by many things, and he doesn't have enough information to pinpoint a specific cause.
He said levels of algae-causing nitrates and phosphorous in the river have steadily increased since annual testing began in 1985. That could be because of human activity, including leaking septic systems or agriculture in the river's watershed.
Bitting said he was disappointed that the Arkansas Department of Environmental Quality didn't do its own testing and relied on the U.S. Geological Survey instead.
The department previously received information from the U.S. Geological Survey regarding its September tests, and a spokesman said last week that the department had received no information from the National Park Service related to its October tests.
"ADEQ has been working collaboratively with the [National Park Service] on water quality-related issues," read the department statement sent to the Arkansas Democrat-Gazette. "In fact, ADEQ has previously offered the use of continuous dissolved oxygen monitors to [the National Park Service] for evaluating the effects of algal blooms on aquatic life."
The National Park Service has detected too-low oxygen levels in Big Creek before, but has never found too-low oxygen levels in the Buffalo River, Bitting said.
Metro on 11/07/2016