From The Pueblo Chieftain (Chris Woodka):
Research on Fountain Creek could improve understanding in the scientific community of how selenium interacts with living tissues. Through five years of study of plants and fish tissue on Fountain Creek, Jim Carsella of the Colorado State University Aquatic Research Center has made an important discovery about the relationship of pH to selenium. “The bioaccumulation of selenium is highest in the spring, but the levels found in water are highest in the fall,” Carsella said. “That’s not what you’d expect to find.”
The reason appears to be related to higher pH levels when flows are lower in Fountain Creek, he said. Graphs show a strong correlation between selenium uptake in fish tissue and the concentration in the stream when the pH levels are in the neutral range. But when they increase toward base (as opposed to acidic) levels, the relationship is destroyed. “This has implications on a worldwide basis on how selenium affects levels in living tissues,” said Del Nimmo, a researcher with CSU-Pueblo.
It’s also important to ongoing water quality issues on Fountain Creek, which is listed as impaired for selenium by the Colorado Water Quality Control Commission. Selenium is an element that is necessary for life, but toxic in higher concentrations. Standards are based on the concentration of levels in fish and birds, as well as what is considered safe for humans.
Research by CSU-Pueblo also has shown an inverse relationship between selenium and mercury in fish tissue, meaning that as selenium increases, mercury decreases. There are high levels of mercury loading on Upper Fountain Creek — possibly from atmospheric sources or from former mining activity. Above Pueblo, selenium levels spike on Fountain Creek because of water flowing over layers of Pierre shale, believed to be the chief reason for higher selenium levels.
More coverage from Chris Woodka writing for The Pueblo Chieftain:
Colorado State University- Pueblo researchers are continuing to monitor Lake Pueblo, the Arkansas River below Pueblo Dam and Fountain Creek as a result of concerns about water quality that began about a decade ago. “Those are the three areas where we are concentrating our efforts,” said Scott Herrmann, an aquatic biology professor who began monitoring the changes at Lake Pueblo before the dam was built.
Like water levels in the Arkansas River basin, the level of enthusiasm for the research being conducted at the university has seen high and low points, particularly over the past five years. “We have a lot of background data on fish and plant species on Fountain Creek, and in the future, we would be interested in repeating the studies,” Herrmann said.
While conditions have changed on the Arkansas River and Fountain Creek, there still is value in the research that has been done to date. “We’re sitting in the catbird’s seat when it comes to data prior to the (Waldo Canyon and Black Forest) fires,” said Del Nimmo, a biologist with the Aquatic Research Center at CSU-Pueblo. Samples taken shortly after the Waldo Canyon Fire have not been tested because of a lack of funding.
Funding for Fountain Creek studies has all but evaporated as government agencies have pulled back.
The previous studies were funded at first by the Lower Arkansas Valley Water Conservancy District, which cut off its support last year after putting more than $400,000 into university studies. The board asked the CSU-Pueblo team to get broader funding contributions last July when it declined to put more money into Fountain Creek.
Pueblo County commissioners have funded about $75,000 per year, while the city of Pueblo and Colorado Parks and Wildlife also have contributed.
The Pueblo Board of Water Works is continuing to fund water sampling in Lake Pueblo and at two points downstream of Pueblo Dam, primarily driven by concern about mussels. The research was helpful in the water board’s recent position on Chlorophyll A levels in Colorado Water Quality Control Commission hearings.
Samples of water taken from Lake Pueblo by Herrmann and Nimmo were used in the discovery of zebra and quagga mussel larvae in 2008, as well as follow-up studies. Most recently, those samples led to the discovery of new invasive species in Lake Pueblo.