Hydrologic Aspects of
Feedlot Waste Control
RICHARD R. DAGUE, Assistant Professor
WAYNE L. PAULSON, Associate Professor
KENNETH J. KLINE, Graduate Student
Department of Civil Engineering
University of Iowa
Iowa City, Iowa
INTRODUCTION
Several segments of the agricultural industry contribute large quantities of
pollutants to the environment. Cattle feedlots are major contributors. Feedlot
wastes have been entering waters for many years, but only in the past five years has
the need for controls become apparent. This need has led to a search for acceptable
waste control operations.
This paper is concerned with the hydrologic factors that require consideration
when designing systems for the control of cattle feedlot runoff. In addition, a discussion of several methods of controlling feedlot wastes is presented.
CATTLE FEEDLOT WASTES
The Cattle Feedlot
A cattle feedlot is an area within which beef animals are confined for feeding
with forage being transported to the animals. In all but rare cases, the feedlot is open
to the atmosphere. The animal density on the feedlot is generally in the range of
50 to 250 head per acre.
Cattle Production
During 1967, the 32 leading cattle feeding states in the United States marketed
21,679,000 fed cattle for slaughter (1). This accounts for most of the total U. S.
production. Production data for the leading cattle producing states are summarized
in Table I. On a national basis, fed cattle marketings are increasing at a rate of
approximately 6.5 per cent/yr. Marketings from feedlots with a capacity of 1,000
head or more are increasing at a rate of about 16 per cent/yr (1). The national trend
is toward the feeding of larger numbers of animals on fewer feedlots.
Feedlot Wastes
Cattle wastes consist primarily of feces and urine from the animals, but also
includes feed spillages on the surface of the feedlot. Several researchers have published data on the characteristics of cattle wastes (2,3,4). Taiganides and Hazen presented guide values for the characteristics of cattle manure (2). These data are presented in Tables II and III. Witzel, et al. published data on the physical, chemical,
and bacteriological properties of bovine animal wastes (3).
Miner et al. published data on the characteristics of cattle feedlot runoff (4).
The data were collected from experimental feedlots located at Kansas State University.
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