Water tests confirm high phosphorous, anabaena levels
Tests done at the Marion Reservoir and streams in the watershed continue to yield troubling results.
And by scanning the results of two biology professors, two conclusions are evident: The anabaena algae was thickest near the Reservoir dam, and excess phosphorous is still a problem in the watershed.
Southwest Missouri State
Dr. Russell Rhodes, biology professor at Southwest Missouri State University, took extensive water samples at Marion Reservoir on Thursday, June 12.
Rhodes tested water at two spots: at the dam and in the middle of the lake. At both places he found three kinds of algae: anabaena, aphanizomenon, and microcystis.
Anabaena algae, the blue-green algae at the root of the county's recent water crisis, can produce toxins that attack the body's nervous system and liver. Microcystis algae is another cyanobacteria, and it too produces toxins, some of which attack the liver or intestinal system.
Aphanizomenon is the typical thick green algae commonly found at the Reservoir. It is harmless, and some people even eat a dried version of the algae for nutritional purposes.
In both locations, aphanizomenon was the dominant algae, especially in the middle of the lake. But near the dam, anabaena counts were high, ranging from 254 units per milliliter at the nine-meter depth to 697.4 units/ml at three meters. Totals amounted to more than twice as much anabaena as microcystis.
But in the middle of the lake, that changed. There was almost twice as much microcystis as anabaena. The amount of anabaena dropped by about 80 percent.
Overall, the anabaena was thickest near the dam and near the surface of the water.
Rhodes predicted that the anabaena bloom would persist through last week. But he added, "with continued cycling of the nutrients from the bottom, the blue greens will probably 'return.'"
Tabor professor
Tabor College biology professor Max Terman recently took water samples from the watershed that drains into the Reservoir. He coordinated his work with the Marion County Conservation District and the U.S. Army Corps of Engineers.
Terman took part in the conservation district's watershed testing that occurred in December of 1998 (see last week's issue for the whole story).
On Wednesday, June 18, Terman sampled water from 10 different sites along the watershed. The area stretched from the Reservoir on the east to Canton on the west.
Among other tests, Terman tested the water for the presence of blue-green algae and phosphorous.
What he found was this: While no blue-green algae existed in the watershed streams, all the phosphorous levels exceeded Environmental Protection Agency regulations.
The blue-green algae was found directly at the Reservoir.
"In a nutshell, blue-green algae was in the Reservoir sites: Cottonwood Point, Durham Cove, and French Creek Cove," Terman said. He didn't find it in the "feeder streams."
But in those streams he did find phosphorous.
According to the EPA, the stream water should contain no more than 0.1 milligrams per liter of phosphorous. All the streams tested on June 18 had levels higher than 0.1.
The site with the most phosphorous was a stream coming off of a pasture northwest of Durham. At that site, the phosphorous level was 1.2 mg/L, Terman said. That's 12 times higher than the EPA allows.
Those excess levels are probably common to other watersheds as well, he said.
"I have a hunch that it's not any worse than any other watershed," Terman said.
