Ohio State Researcher to Re-write Ohio’s Phosphorus Index to Improve Water Quality

Nov 06, 2012

Ohio State Researcher to Re-write Ohio’s Phosphorus Index to Improve Water Quality

P Risk Index tile drainage

COLUMBUS, Ohio -- Grand Lake St. Marys has lost an estimated $60-80 million in tourism due to harmful algae blooms. And in 2011, algae blooms covered 990 square miles of Lake Erie’s surface area, the largest in the lake’s history. Phosphorus is the pollutant most often implicated in the degradation of Ohio’s fresh surface water, with use of phosphorus fertilizer on farmland as a contributing factor. 

To help mitigate these water quality issues, an Ohio State University researcher has launched a $2 million project to evaluate and, as necessary, revise the U.S. Department of Agriculture-Natural Resources Conservation Service Ohio Phosphorus (P) Risk Index to better predict the risk of phosphorus moving off farm fields.  

Elizabeth Dayton, a soil scientist in Ohio State’s School of Environment and Natural Resources, garnered a $1 million USDA Conservation Innovation Grant and $1 million in matching donations from Ohio agribusinesses to complete the project. 

Her goals are to make the Ohio P Risk Index accurate, add more best management practice options for farmers, and create an interactive web-based tool so farmers can calculate their P Risk Index scores, evaluate management options and make informed decisions to better manage phosphorus. 

Because the Ohio P Risk Index is used by farmers statewide in developing nutrient management plans for both manure and commercial fertilizer application, it is important that the P Risk Index be as accurate an indicator as possible. 

“With increased degradation of surface water in Ohio, agriculture has increasingly been cast in the role of the villain,” Dayton said. “A robust, functioning Ohio P Risk Index will give farmers a better tool to manage field scale phosphorus transport, while sustaining agricultural productivity and protecting surface water quality.”      

The research will focus on, but is not limited to, Grand Lake St. Marys and the Western Lake Erie Basin, two of Ohio’s most problematic watersheds. 

Ohio's agricultural industry is showing its concern about the phosphorus problem in Ohio by providing matching contributions to the project, including those from the Ohio Soybean Council, Ohio Small Grains, and The Andersons, Inc. 

“The tremendous support we have received from Ohio agribusinesses demonstrates their commitment to good stewardship and to being part of the solution,” she said.  

Tom Fontana, director of New Use Development for the Ohio Soybean Council, agrees. 

“Water quality is a top concern in Ohio, and farmers want to be part of the solution,” he said. “Ohio State’s research to validate and update the Phosphorus Risk Index will help us determine what the next best management practices are when it comes to phosphorus use on the farm. 

“It will also help farmers statewide to reduce the risk of phosphorus runoff, which in turn, better protects Ohio surface water quality.” 

Ohio State's School of Environment and Natural Resources is part of the College of Food, Agricultural, and Environmental Sciences.



Tracy Turner


Elizabeth Dayton

My OSU Extension
Dan Crouse

“What I've learned in this process is that marketing is everything. Business Retention & Expansion has helped debunk a lot of downtown perceptions that have stifled economic growth.”

Dan Crouse
Warren, Ohio

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