So you thought phosphorus was the only issue for Ozark streams? You may want to think before you drink!
Report: Many Chemicals In Northwest Arkansas Streams
Samples Show Compounds Below Treatment Plants..."NW Arkansas Morning News"
By Dan Craft
The NW Arkansas Morning News
FAYETTEVILLE -- Phosphorus may be the buzzword in the Illinois River basin, but one researcher is looking at other compounds in the water.
Joel Galloway of the U.S. Geological Survey has found chemicals including caffeine, steroids, antibiotics, DEET, creosote and phenol in several Northwest Arkansas streams. He presented his findings Wednesday to the annual conference of the Arkansas Water Resource Center.
"These are things you associate with people, but not necessarily with agriculture," Galloway said. "Basically, this is what we flush down the toilet and wash down the sink."
While phosphorus is easily measured because of its quantity in the water, most of the compounds sampled by Galloway are present in much smaller amounts.
"Some of these values are so small they have to be estimates," Galloway said. "There's enough there to detect and identify, but the concentrations are too low for the lab to report a solid value."
One chemical that showed a reading of more than one microgram per liter was erythromycin, a popular antibiotic medicine.
Samples also indicate that some compounds are present in most streams, and that concentrations increase downstream from area wastewater treatment plants, Galloway said.
A site on Spavinaw Creek above Decatur Branch, upstream from the outlet of Decatur's treatment plant, was the only site showing no chemical readings among those sampled, Galloway said.
A national study published in 2003 recording the presence of previously ignored chemicals has brought attention to the topic, said Ralph Davis, conference director.
"Along with phosphorus, this has become one of the big hot-button issues lately," Davis said.
None of the chemicals sampled occur naturally in streams, and none were found in an undeveloped, natural baseline sample site at Sylamore Creek near the Buffalo National River, Galloway said.
"We've got fire-retardants, fragrances, all sorts of chemicals that are manmade and man-used," Galloway said. "None of this was in the stream to begin with."
Galloway plans to follow up with additional research on the sources, transport and impact of the various chemicals.
"Finding that it was there was just the first step," he said. "Now, we need to see how it goes through the system and what effect it has on the streams."
Most of the compounds Galloway sampled are not regulated in water quality standards, so identifying their presence doesn't mean that monitoring, such as that done for phosphorus levels, will occur, Galloway said.
"I don't know that we can stop it, but we sure need to find out more about it," he said.
Another presentation Wednesday, however, did focus on phosphorus.
Brian Haggard and Thomas Soerens shared their work on whether Lake Francis along the Arkansas/Oklahoma state line is acting as a strainer of sorts for phosphorus.
"Our work shows that the simple fact that Lake Francis is there could affect phosphorus concentrations," Haggard said. "Arkansas is monitoring upstream and getting one reading, but it doesn't match the readings Oklahoma is getting just downstream."
The dam that created Lake Francis was breached years ago, leaving the lake as more of a stream that expands during high water flows, Haggard said.
"The question is how much phosphorus is flowing right through the lake and how much is staying there, only being released when the water gets up high and flushes it out," Haggard said. "I think Lake Francis is going to be a problem, one that we're all going to have to consider."
Other presentations at the conference considered the current status of several underground aquifers in south and east Arkansas.
"This isn't something that people in Northwest Arkansas think much about, because aquifers aren't a big issue here," said Davis, the conference organizer. "In other areas of the state, though, irrigation from aquifers is a major concern."