Study finds chicken manure pollution overstated

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By Daniel Menefee

Chickens in chicken house

Photo by chesbayprogram

Eastern Shore farmers and representatives of the poultry industry told lawmakers Friday that EPA estimates on nutrient pollution from poultry production are outdated and way overstated, according to a new study from the University of Delaware.

The U.S. Environmental Protection Agency estimated in the 1980s that Delmarva poultry growers contributed 6% of all nutrient runoff into the Chesapeake Bay.

“The EPA is using a formula that is about 30-years-old,” said Delmarva Poultry Industry Inc., President Andrew McLean. “It does not reflect today’s chicken breeds and chicken raising methods.”

The study conducted by James Glancey at the University of Delaware indicated the volume of manure from the current breed of chicken is much lower than in the 1980s and that nutrient concentrations (nitrogen and phosphorus) estimated by EPA then were 1½  times greater for nitrogen and 2½ greater for phosphorus, according to the study.  Glancey’s study factored in new management practices, feed technology, and genetics that improved efficiencies over the last 30 years.

The Eastern Shore poultry industry is feeling the weight of regulators to bring the state into compliance with an EPA mandated Watershed Implementation Plan by 2020 – which reduces nutrient runoff into the Bay in increments by 2020.

Poultry growers are frustrated that EPA’s old estimates are the basis for Maryland’s Watershed Implementation Plan that was approved by the EPA in 2010.

Delmarva Poultry Industry Executive Director Bill Satterfield said miscalculating nutrient pollution from poultry will steer regulators and resources away from larger nutrient pollution sources.

“The current data that assigns responsibility is inaccurate,” Satterfield said. “We need to make sure correct data are used to assign responsibility.”

Satterfield said poultry growers worry that EPA would be too slow to adopt the science before the Watershed Implementation Plan for Maryland was fully implemented.

McLean said the University of Delaware and the Delaware Department of Agriculture are trying  to convince the EPA to use “a new science-based calculation of manure production and nutrient concentration.” He said the EPA working group for Chesapeake Bay the watershed plan is considering the data.

Jennifer Timmons, a poultry specialist with University of Maryland College of Agriculture participated in the University of Delaware study and said EPA is slow to adopt findings in new studies that are not yet published or peer reviewed. Glancey’s study has not cleared those hurdles, Timmons said, “but the EPA working group is looking at his data.”

Glancey said by phone that peer review and publication were not necessarily holding up adoption of his findings, but that the EPA-Chesapeake Bay working group was waiting for all six of the Bay states to submit their own studies.