February 13, 2018

Exploring Variations in Water Quality Parameters in the Raccoon River

Rivers are incredibly dynamic ecosystems. To paraphrase the Greek philosopher Heraclitus, no one ever steps into the same river twice, because it’s not the same river nor the same person. A team of scientists from Drake University has been investigating changes in the Raccoon River at various locations over an 18-month period.

“The goal of our work is to understand the patterns of the Raccoon River across space and time,” said Peter Levi, a faculty member in Drake University’s Department of Environmental Science and Sustainability.

Every two or three weeks since June 2016, Levi and several students from Drake visit nine sites in the South, Middle, North, and mainstem Raccoon River. The sampling sites are bridges and boat ramps – from Minburn and Redfield to downtown Des Moines

Levi and his team have been focused on several key parameters that are important metrics of water quality: suspended sediment, nutrient concentrations in the water, and the rates of sediment denitrification (a natural microbial process that permanently removes nitrate from river water). Together, measuring these parameters at frequent intervals over an 18-month time period will allow the scientists to investigate the influence of seasonal changes and land-use on water quality in the lower Raccoon River watershed. The field component of the research will continue through December, but Levi has already seen interesting results.

“The different branches of the river fluctuate so much between each other on the same date and within the same branch across dates. It will be exciting to wrap up the fieldwork and start to analyze the patterns in relation to climate and landscape data.”

The research by Drake’s Stream Ecosystem Ecology Lab (SEEL) has been a community effort. Teams of citizen scientists were deployed to sample the Raccoon River at more points in July 2017. Three teams of volunteers covered over 80 river miles in just three days. The intensive sampling will provide the researchers an opportunity to understand how each branch varies at a much finer scale.

In August 2017, Des Moines Water Works agreed to provide Drake University analytical assistance for the monitoring project of the Raccoon River.  This laboratory support is provided at a reduced rate, saving Drake approximately $30,000.

“We appreciate Peter Levi’s work and Drake’s support of monitoring nutrient trends and natural denitrification rates in the Raccoon River,” said Bill Stowe, CEO and General Manager. “This project could be the start of a great partnership examining nutrients in our source waters.”

Posted by: Laura Sarcone No Comments
Labels: , , Posted in Source Water, Uncategorized, Water Quality

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