...From the pages of Agricultural Research magazine
Recycling Feedlot Runoff
Cattle, unlike humans, do not have the luxury of flushing
their waste down the toilet into elaborate treatment systems. But livestock
producers have various ways of protecting the environment from cattle
waste, and one method is to collect all the runoff from feedlots in
special temporary storage ponds.
These ponds do protect the environment, but they sometimes
leak. Also, they smell bad and have to be emptied regularly. Agricultural
engineers with the Agricultural Research
Service have designed a system that solves these problems and comes
with additional benefits.
At the Roman L. Hruska U.S. Meat Animal Research Center
(MARC) in Clay Center, Nebraska, John A. Nienaber, Roger A. Eigenberg,
and Bryan L. Woodbury have designed a system for beef cattle feedlot
runoff control and treatment that, once built, requires little work
from the farmer.
The feedlot at MARC is situated on top of a foothill.
Rainfall runoff from a series of pens within this feedlot is directed
to a shallow basin that runs the length of the pens. The runoff is collected
and retained in the basin less than an hour, allowing the solid particles
to settle. The runoff is then discharged to a hayfield, where the water
and nutrients help the hay grow.
The retained solids have to be removed from the basin
once a year. They are spread on cornfields as a soil fertility amendment.
"This system is a great way for small to medium-sized
facilities to recycle nutrients from animal manure," says Woodbury.
Thousands of acres of corn and hay are planted each year
for cattle to eat. Cattle are not able to use all the nutrients, such
as nitrogen and phosphorus, contained in the feed. With this system,
those nutrients are used to help grow the food cattle will eat, which
saves money and prevents the nutrients from going into the environment.
In the 3 years that the agricultural engineers have studied the system,
there has been no runoff of nitrogen from the hayfields to the surrounding
Nienaber points out that the costs of designing, building,
and maintaining this system are less than those for traditional ponds.
It costs a lot of money and time to build the large ponds and to periodically
pump the waste out of them.
Woodbury says the project will last another 5 years. During
that time, the scientists will continue to evaluate the system's effectiveness.By
David Elstein, Agricultural
Research Service Information Staff.
This research is part of Manure and Byproduct Utilization
(#206), an ARS National Program described on the World Wide Web at www.nps.ars.usda.gov.
L. Woodbury, John
A. Nienaber, and Roger
A. Eigenberg are with the USDA-ARS Roman L. Hruska U.S.
Meat Animal Research Center, P.O. Box 166, Clay Center, NE 68933-0166;
phone (402) 762-4275 [Woodbury], (402) 762-4274 [Nienaber], (402) 762-4272
[Eigenberg], fax (402) 762-4273.
"Recycling Feedlot Runoff" was published in the April 2003 issue of Agricultural Research magazine.