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THK ECONOMICS OF CLEAN WATER
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THE ECONOMICS OF
CLEAN WATER
VOLUME II
Animal Wastes Profile
LIBRARY, NFIC • DENVER
ENVIRONMENTAL PROTECTION AGENCT
U. S. Department of the Interior
Federal Water Pollution Control Administration
March 1970
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UNITED STATES
DEPARTMENT OF THE INTERIOR
OFFICE OF THE SECRETARY
WASHINGTON, D.C. 20240
APR 3 1970
Dear Mr. President:
I am transmitting to the Congress the third report on the national
requirements and cost of water pollution control as required under
Section 16 (a) of the Federal Water Pollution Control Act, as amended.
The decade of the 1970's, a decade which will address Itself to Improv-
ing the quality of man's environment, will see great strides toward
the effort to abate water pollution. The enclosed report entitled
"The Economics of Clean Water" represents our current estimates of the
investment levels necessary to attain applicable water quality
standards.
This report, along with the two previously submitted, contributes to
closing the information gap in terms of the overall magnitude, geograph-
ical, and financial dimensions, all of which are essential to the
development of national policies and programs directed toward achieving
water quality standards in an efficient and effective manner.
The alternatives analyzed in the course of this study, especially
those aspects contained 1n Volume I, presented valuable background
for development of proposals on aid to municipal treatment works
presented to the Congress In the President's Environmental Message
and subsequent legislation.
There are four parts to this year's report. The first is a summary of
major findings and conclusions of the analysis. The second, Volume I,
contains the details of the analysis. The third, Volume II, is a
profile of animal wastes. The fourth and last section, Volume III,
1s an Industrial profile of the Inorganic chemicals Industry.
Sincerely yours,
Secretary tff the Interior
Hon. Splro Agnew
President of the Senate
Washington, D. C. 20510
Enclosure
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UNITED STATES
DEPARTMENT OF THE INTERIOR
OFFICE OF THE SECRETARY
WASHINGTON, D.C. 20240
APR 3 1970
Dear Mr. Speaker:
I am transmitting to the Congress the third report on the national
requirements and cost of water pollution control as required under
Section 16 (a) of the Federal Water Pollution Control Act, as amended.
The decade of the 1970's, a decade which will address itself to improv-
ing the quality of man's environment, will see great strides toward
the effort to abate water pollution. The enclosed report entitled
"The Economics of Clean Water" represents our current estimates of the
investment levels necessary to attain applicable water quality
standards.
This report, along with the two previously submitted, contributes to
closing the information gap in terms of the overall magnitude, geograoh-
ical, and financial dimensions, all of which are essential to the
development of national policies and programs directed toward achieving
water quality standards in an efficient and effective manner.
The alternatives analyzed in the course of this study, especially
those aspects contained 1n Volume I, presented valuable background
for development of proposals on aid to municipal treatment works
presented to the Congress in the President's Environmental Message
and subsequent legislation.
There are four parts to this year's report. The first is a summary of
major findings and conclusions of the analysis. The second, Volume I,
contains the details of the analysis. The third, Volume II, is a
profile of animal wastes. The fourth and last section, Volume III,
is an industrial profile of the Inorganic chemicals industry.
Sfincerely yours,
Secretary of the Interior
Hon. John W. McCormack
Speaker of the House of
Representatives
Washington, D. C. 20515
Enclosure
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CONTENTS
SUMMARY xi
INTRODUCTION 1
Water Pollution Control and Wastes Management 2
OVERVIEW OF ANIMAL WASTES PRODUCTION 3
Trends Affecting Animal Numbers 4
OVERVIEW OF COST ESTIMATION 9
COMMON CHARACTERISTICS OF ANIMAL WASTES DISCHARGES 11
Regular Discharges 12
Description of Water Flushing Methods Used in Dairy, Swine,
and Poultry Operations « .*..*.. 14
Dairy 14
Swine 15
Poultry 15
Direct Contact of Animals With Watercourses 17
Intermlttent Discharges 18
Seldom Discharges 22
Never Discharges 24
Summary of Classes of Discharges 25
CATTLE , 26
Beef Cows 26
Fat Cattle 29
Animal Wastes That Cause Water Pollution 29
Factors affecting runoff of potential wastes 34
GRASS FATTENED CATTLE 38
Low Density 38
High Density 38
CONCENTRATE FATTENED CATTLE 41
Number of Feedlots 42
Discharge Frequency 42
C11mate 43
Major Feeding States 46
Feedlot Capacities 46
Conwon Control Methods 62
Description of Selected Control Methods 65
Diversion 66
Detention 67
Covered Operations 71
vii
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Table of Contents (Continued)
DAIRY CATTLE 74
Location of Milk Cows 75
Common Control Methods 75
POULTRY 77
Broilers and Layers 77
Location of Broiler Production 77
Location of Layers 79
Ducks 79
Turkeys 80
SHINE 80
Location of Swine Enterprises 80
Common Control Methods 82
SHEEP 84
LIST OF FIGURES
1. Per capita consumption—beef* pork, veal, lamb and mutton, and
poultry, 1959 through 1968 5
2. Production of red meat and poultry, 1959 through 1968 6
3. Meat and poultry production, 1959 through 1968 7
4. United States population, 1945 through 1968 with projection
for 1975 8
5. Major components of the farm livestock Industry that must be
analyzed to estimate water pollution control costs 10
6. Cattle slaughter, 1959 through 1968 30
7. Schematic drawing of the components of Fat cattle operations
that affect the water pollution potential of the animals. 31
8. Graphical description of pollution per animal contained 1n a
given ralnfal 1 runoff 36
viii
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Table of Contents (Continued)
LIST QP TABLES
1. Number of reported fish kills and total number of fish killed
as a result of manure, silaqe, or feedlots drainage, 1964
through 1968 ". 42
2. Number of cattle marketed by size groups and number of feedlots
in each size group--1968 43
3. Number of cattle marketed and number of feedlots by top ten
States in terms of the number of cattle marketed from feedlots
with over 1000 head capacity--1968 49
4. Number of feedlots in selected States with under inoo head
capacity, number of cattle marketed from them, and their
average annual marketings--1968 52
5. Number of feedlots in selected States with 1000 head capacity
and over, number of cattle marketed from them, and their
average marketings--1968 53
6. Number of cattle feedlots in various specified size groups in
selected States—1968 55
7. Number of cattle feedlots in various specified size groups in
selected States—1962 57
3. Total operating feedlots and total cattle and calves on feed
by specified feedlot size group, Aoril 1, 1966 59
9. Total operating feedlots and total cattle and calves on feed
by specified region, April 1, 1966 61
10. Number of milk cov/s on farms, 1944-1969 .-^."7 74
LIST OF HAPS
1. Number of beef cows two years old and older kept on farms, by
State—January 1, 1969 27
ix
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Table of Contents (Continued)
2. Number of cattle marketed out of all feedlots by the fourteen
States with largest marketings In 1968, location of major
Feeding States, and percent of cattle marketed from feedlots
with capacities 1000 head and greater 47
3. Number and percentage of cattle marketed from feedlots with
capacities of 1000 head and greater located 1n the fourteen
States with largest marketings 1n 1968 50
4. Number of feedlots of under 1000 head capacity and number of
cattle marketed from them for ten selected mldwestem States,
1968 51
5. Description of geographic regions 60
6. Number of milk cows on farms, by States, June 1969 76
7. Location and number of commercial broilers produced In 1968,
and of layers on hand during October 1969 78
8. Location and number of turkeys raised 1n 1968 81
9. Number and location of hogs on farms January 1, 1969 83
10. Number and location of sheep and lambs on farms January 1,
1969 85
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SUMMARY
The total costs associated with controlling water pollution from
animal wastes cannot be estimated at this time. However, certain
general conclusions can be drawn as to the scope of the problem, pos-
sible control measures, and the location of major pollution sources
or broad areas of probable pollution from animal wastes.
In many cases animal wastes have proved to be significant pollu-
tion sources that resulted in fish kills and extensive damage to the
ecology of the streams. Additionally, the wastes handling and disposal
methods employed by many enterprises make them probable contributors
to water pollution even though the present stream monitoring procedures
and networks are not comprehensive enough to pinpoint all such nonpoint
discharge sources.
In various efforts to assess the water pollution potential of
animal wastes, with the lack of information on the extent of pollution
from these sources or on control measures that might be used, many
reports have tended to view the problem in its most extreme state.
That 1s, they consider all the animal wastes (regardless of origin
or manner of disposition) which means that the population equivalent of
that volume of wastes 1s disproportionately greater than the population
of the United States. If such a population equivalent of animal wastes
1s then multiplied by the treatment costs per person for sanitary
wastes, the resulting comparative costs are staggering and misleading.
At the present time, however, there 1s general agreement that not
all of the wastes need to be considered as sources of water pollution.
Therefore, it would seem that entirely too much emphasis has been
placed on the gross possible costs of controlling water pollution from
animal wastes. A more realistic base for use 1n developing programs
for water pollution abatement and control from animal wastes Is a
series of sub-elements that can be Independently assessed to determine
their pollution potential, applicable control measures, and total
pollution control costs.
The prime advantages of the sub-element approach are: (1) the
ability to estimate portions of the total animal wastes pollution
control picture over time which Is Important when resources for assess-
ment are constrained, (2) the opportunity to design specific programs
for various portions of the total problem, and (3) the provision of
the necessary breakdown of the problem for comparing marginal effec-
tiveness of treating various aspects of the total problem. In any
period when resources for correction or control of pollution problems
are constrained, 1t is highly desirable to deal first with those
problems that provide the most return for the scarce resources
available.
xi
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Animal wastes should be broadly subdivided by Animal species, not
because there is no similarity of problems or control measures but
because the regional animal concentrations, future growth, and specific
application of control measures vary substantially from species to
species. Within each species are additional useful breakdowns that
may be utilized for comparative purposes as well as for analytical
convenience. For example, the major emphasis in this report is on the
fat cattle industry. Within this major breakdown of the animal wastes
problem are several subdivisions which cover such items as size,
location, and applicable control measures.
Frequency of waste discharge and number of animals or total wastes
involved in the discharges are primary criteria for use in categorizing
animal wastes problems. Regular or daily discharges, such as those
from enterprises using water flushing systems, should be analyzed early
in the process of assessing the contribution of animal wastes to water
pollution because of their high probability of being sources of water
pollution and because of the growing use of flush systems in dairy,
poultry, and swine enterprises.
Intermittent wastes discharge sources with high total pollution
potential, such as beef feedlots subject to runoff, also deserve
early attention when the animal wastes contribution to water pollution
is assessed. The discharges from this class are less frequent per
individual enterprise but the nunber of animals, volume of wastes, and
the number of enterprises involved significantly increase the water
pollution potential.
Specific Information relative to actual pollution occurring by
local area or region is not available. However, the number of animals
in each State during some given time period provides an indication of
the relative water pollution potential in each State from various
animal sources. For example, the midwestern area, California, and
Texas generally have high numbers of all types of animals and particu-
larly of the larger-sized animals with high wastes production per
animal. Other areas such as the northeastern and southeastern sections
have large numbers of specific animals such as dairy and poultry,
respectively.
Common Control Methods for Beef Feedlots
Beef feedlots are known sources of water pollution but the extent
and distribution of pollution caused by such feedlots is unknown.
Further, the present state of knowledge does not permit an adequate
estimation of the numbers of types of control facilities that are need-
ed to control water pollution from feedlots. However, an indication of
the size and variability of the control problem may be obtained through
a general discussion of the known control methods and their applica-
bility under varying conditions.
xii
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Types of pollution control measures utilized by feedlot enterprises
vary significantly across the Nation as well as within a specific local
area. There is no one best solution for controlling pollution from
feedlots although there are solutions that have greatest general
applicability to feedlots in similar situations. In fact, it is this
general applicability in similar situations which will make possible
more realistic future estimations to be made as to the total costs of
controlling pollution from animal feedlots.
Control measures range widely in complexity and cost. Minimal
control measures, in terms of cost and complexity, are water diversion
systems that divert drainage water around the feedlots, changes in the
drainage route of runoff from feedlots, and, possibly, changes in lot
locations to minimize drainage water moving across the lot or to
prevent direct drainage from the lot to a watercourse. Other changes
in operations such as increasing animal concentrations or adjusting
feeding cycles to meet changing climatic conditions can also be used
to reduce or eliminate water pollution from feedlots with minimum
expendi tures.
More costly control measures, at least in terms of capital
investments and operating costs, would include systems with completely
covered feeding operations and full treatment of the wastes. Of course,
between the minimal control situation and the maximum control situation
there are numerous other control measures and combinations of these
measures that can be used.
The type of control measure adopted depends upon a variety of
factors chief among which are the quantities of water that must be
contained or diverted, the possibility of cost savings, and the ability
of the system to offset Inadequate labor supplies. Intertwined with
these chief factors in determining the type of control measure to be
adopted are such things as lot size, climate, and type of feeding
operation. These factors are, of course, reflected to an extent In
the present geographical distribution of feedlots by sizes throughout
the United States.
Major Feeding States
The 32 major feeding States accounted for over 23 million head of
cattle marketed from feedlots in 1968. About 20.2 million head were
marketed from feedlots in the 14 States with the largest marketing from
feedlots in 1968. It is therefore apparent that the bulk of the
feedlot cattle operations are concentrated in relatively few States.
Even more Important from a water pollution standpoint is the fact that
cattle feedlots are generally more heavily concentrated 1n specific
sections of these States. As a result, the pollution potential, both
in total magnitude and in the cumulative effect along a watercourse,
is very high for such localized areas.
xlii
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Feedlot Capacities
Feedlots with capacities of 1,000 head or over accounted for almost
half of the total cattle marketed out of feedlots in 1968. However, by
virtue of the capacities of these larger feedlots, they only account
for about one percent of all feedlots. In other words, the 2,080 lots
of 1,000 head or over capacity marketed almost 11 million head of the
slightly more than 23 million head marketed from all feedlots in 1968.
The other 206,516 feedlots of less than 1,000 head capacity accounted
for the remainder of the cattle marketed from feedlots.
Almost 90 percent of the cattle from feedlots with capacities of
1,000 head or more come from 10 States west and south of the Missouri
River. These States account for 1,522 of the 2,080 feedlots reported
to have had a capacity of 1,000 head or more in 1968. On the other
hand, 10 midwestern States, including an overlap of Kansas and Nebraska
previously included in the large lot category, account for the bulk of
the small feedlots and cattle marketed from them. These 10 States
account for 185,264 lots out of the total in this under 1,000 head
size group of 206,516 and for about 10.6 million out of a total of
12.2 million head marketed from this smaller size group.
Many of the lots of under 1,000 head capacity are extremely small.
The average size of lots under 1,000 head in the five States with the
largest number of feedlots is only 65 head and the average of the 10
midwestern States is 57 head.
As would be expected, the number of feedlots in each size category
declines very rapidly as the lot capacities increase beyond 1,000 head.
However, the trends indicate that all feedlot sizes will be increasing
and that there will be continued growth in the numbers of large-scale
lots. The 32-State totals show that the bulk of the 1,000 head
caoacity lots fall within the 1,000 to 3,999 head capacity range. In
fact, if the range is expanded to include up to 7,999 head capacity
lots, this new range includes 1,805 of the 2,030 lots with capacities
of 1,000 head and greater.
From the foregoing discussion it is evident that there are some
definite points to be considered when assessing the need for, and
applicability of, different pollution control measures for various
sized feedlots. Additional breakdowns of the large-scale feedlot
figures show that 9C out of a total of 99 feedlots with capacities
of 16,000 head and over are accounted for by nine of 10 top States in
cattle marketings from lots over 1,000 head capacity. Also, it shows
that these 10 States account for 252 of the 275 lots with capacities
of 3,000 head or more.
xiv
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Feedlot capacities cover the broad spectrum of size ranges from
less than 50 head to over 30,000 head capacities. However, there are
definite groupings of lot sizes within this range. These size group-
ings, although not all-inclusive, follow a general geographic pattern
related to climate. Most of the large feedlots, for example, are
located south and west of the Missouri River. Although specific
feedlot locations and corresponding climatological data are not present-
ly available, it is known that the climate is less severe in most of
these States than in the States where the majority of the small lots are
located. In fact, in several of the States with the majority of the
large lots, the climate can be considered as dry.
Another perplexing problem, in terms of evaluating the current
pollution problem and forecasting future changes, is how to differen-
tiate size groups in the 206,516 lots of under 1,000 head capacity.
In this size group the average number of cattle marketed in 1968 was
59 head. Even if the lots are restricted to those found in the 10
midwestern States with somewhat similar climatic conditions, the
magnitude of the problem remains large. That is, in these 10 midwestern
States there were 185,264 lots of under 1,000 head capacity. About
10.6 million head of cattle were marketed out of these lots in 1968 for
an average marketing of 57 head.
XV
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INTRODUCTION
Previous Cost of Clean Water reports have covered the basic
questions with respect to animal wastes. In brief, they point out that
water pollution from animal wastes is a very significant and growing
problem. These conclusions stem primarily from information on total
wastes produced by farm animals, the growing demand for animal products,
and trends toward fewer farm units with greater concentrations of
animals on the remaining units.
These earlier reports, as well as many other past and current
reports, rely heavily upon showing the gross magnitudes of animal
wastes produced. These gross figures are often cited in hopes that
they will lead readers to the inescapable conclusion that, even after
discounting for overstatement, animal wastes are still a serious
problem.
Despite the value of using this gross magnitude method to make
people aware of a problem, there is an obvious drawback in that people
may either overreact and conclude that the problem is too big to
handle or underreact and conclude that such figures are too far off
target to be taken seriously. Therefore, in order to receive the
needed understanding and support for pollution control efforts in the
animal wastes area as well as to develop plans for attacking the pro-
blem, it is necessary to have available some reasonable estimates of
the true magnitude of the problem.
Although these other reports drew some very broad conclusions
as to the magnitude and future of the problems, they did point out
that little was known about the actual amounts of pollutants reaching
the waters, the available control measures, or the costs of these
controls. This current report also admits to a lack of data regarding
the aforementioned items, however, this section's objective is to
provide a comprehensive view of the problem, to setup a framework that
can be used for future study, and to discuss the known facts and point
out areas with potential for fruitful future study. This report
concludes that water pollution as a result of improper or inadequate
disposal of animal wastes can be a major but manageable problem. It
also points out that further study may show that 1n many cases the
net costs of control may not only be manageable but very minimal, if
at all existent, when offsetting economies of the changed operations
are considered.
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Water Pollution Control and Wastes Management
The characteristics and volume of animal wastes produced daily
preclude a simple separation of the water pollution aspects from the
total problem of waste management. Actually, operators of animal
raising or fattening enterprises are often more concerned with the
total wastes accumulated in their operations than they are with the
amount of water pollution caused by these wastes.
An operator's concern with the wastes accumulations is under-
standable in that the problems and costs associated with waste
management in large scale operations are immense. It is, therefore,
desirable and advisable to view the water pollution control aspects
of the enterprise's wastes as a part of the overall waste management
system. Also, it is likely that in many cases changes in waste
management practices will result in water pollution control.
Conversely, adoption of a water pollution control system might result
in a solution to the waste management problem.
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OVERVIEW OF ANIMAL WASTES PRODUCTION
From an overall point of view, the water pollution potential of
animal wastes hinges upon the demand for all animal products. Increas-
ing consumption means that more animals must be raised to meet the
rising demand, whereas, decreasing demand causes an opposite effect on
production. The result of raising more animals to meet a rising
demand is a corresponding increase in animal wastes produced.
The actual change in quantities of wastes produced depends upon
the types of animal products demanded. For example, beef cattle
wastes are much different quantitatively and qualitatively than
poultry or swine wastes. This means that as the demand for one type
of meat changes, the pollution potential of the entire industry
changes in proportion to the wastes of that species. However, the
potential does not change in a simple one-to-one ratio that would
occur if all the waste characteristics of each animal species were
the same.
An example of a one-to-one change would be where the demand for
beef increased by a certain number of pounds while the demand for
poultry decreased by a like number of pounds leaving the total
demand for meat unchanged. In this case a one-to-one ratio for waste
characteristics would mean that there would be no net change in:
total wastes produced; their characteristics; or their potential
for entering a watercourse.
Because there is not a one-to-one wastes ratio, any definitive
estimate of the cost of controlling wastes from meat animals requires,
in addition to analysis of technical questions on waste production
and control, projection of consumption and production trends for
each animal species. Similar production and consumption factors will
also have to be analyzed to predict the costs of controlling wastes
from dairy animals.
The major objectives of this section are to define the animal
wastes problem and to set forth a framework for estimating costs of
controlling these wastes to whatever degree necessary to prevent
water pollution. Since the report is of a preliminary nature, it is
premature and unnecessary to delve deeply into the consumption and
production trends of the various animal species. Rather, a superfi-
cial look at these trends to gain some insight into the potential
of the problem is adequate until we can come to grips with the techni-
cal aspects of such things as runoff prediction, acceptable treatment
or control measures, and estimating costs of providing the various
treatment or control measures,
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Trends Affecting Animal Nimbers
Meat consumption in the United States has been trending upward
over the years. This upward trend has been evidenced in both the per
capita consumption and the total consumption figures. Although many
factors affect meat consumption, it is generally agreed that per
capita consumption is directly related to disposable income. Income
also has an effect upon the preferences of people when choosing among
meat products. Per capita beef consumption, for example, usually
increases as incomes rise even though consumption of pork, poultry, or
lamb may be falling during the same period. (See Figure 1.) A
comparison of Figures 1, 2 and 3, shows the result of the interaction
between consumption, population, income and other related factors
that affect production.
As can be seen in Figure 2, the pounds of meat produced annu-
ally, which is an indicator of consumption, are increasing at a
rather steady rate that is probably directly related to population
and income. If population and income projections for the next several
years prove accurate, then the increases in animals raised or main-
tained to meet the greater demand for meat products will significantly
compound the animal wastes disposal problem. Certainly the effect of
population will not be reversed although there may be a change in the
slope of the population trend. Figure 4 shows the population trend
in recent years and the census projection through 1975. In general,
then, it is reasonable to conclude that a more detailed study of animal
wastes production from a potential water pollution source standpoint is
warranted. As necessary, a more detailed review of the consumption and
production trends within any phase of the animal industry will be given
in the appropriate section of this report.
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Figure 1
Per Capita Consumption-Beef, Pork, Veal, Lamb
and Mutton, and Poultry, 1959 through 1968.
Pounds
110
100
90
80
70
60
50
40
30
20
i
10
5
0
L»^
«Beef »*•'
Pork
_ Poultry
Veal
Lamb & Mutton
1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
SOURCES: Livestock and Meat Statistics-Supplements for 1967 and 1968 to Statistical
Bulletin No. 333, U.S. Department of Agriculture Economic Research Service-
Statistical Reporting Service-and Consumer and Marketing Service,
Washington, D.C.
Poultry and Egg Situation-June 1969, Economic Research Service, United States
Department of Agriculture, Washington, D.C.
-------
Figure 2
Production of Red Meat and Poultry, 1959 through 1968.
<
<-.
-
+
46—
44—
42—
40-
38-
36-
34-
32-
30-
28—
26—
24—
Total
Shaded Area
Equals Chicken
and
Turkey Production
Red Meat
0
i
I
I
I
I
I
I
I
I
1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
SOURCES: Livestock and Meat Statistics-Supplements for 1967 and 1968 to
Statistical Bulletin No. 333, U.S. Department of Agriculture,
Economic Research Service, Statistical Reporting Service, and
Consumer and Marketing Service, Washington, D.C.
Poultry and Egg Situation, June 1969,
Economic Research Service, U.S. Department
of Agriculture, Washington, D.C
-------
o
Q.
c
o
m
20.0
19.0
18.0
17.0
16.0
15.0
14.0
13.0
12.0
11.0
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0
SOURCES:
Figure 3
Meat and Poultry Production, 1959 through 1968.
Beef
****
Chicken
Veal
Turkey
i i
I i
1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
Livestock and Meat Statistics--Supplements for 1967 and 1968 to Statistical Bulletin
No. 333/U.S. Department of Agriculture, Economic Research Service-Statistical
Reporting Service- and Consumer and Marketing Service, Washington, D.C.
Poultry and Egg Situation, June 1969, Economic Research Service,U.S. Department
of Agriculture Washington, D.C.
-------
CD
Figure 4
United States Population, 1945 through 1968 with
Projections for 1975.
(Millions)
230
220
210
200
190
180
170
160
150
140
ot
f
1945
1950
1955
1960 1965
1970
1975
SOURCE: Current Population Reports, Bureau of the Census, United States
Department of Commerce.
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OVERVIEW OF COST ESTIMATION
Estimation of the costs of controlling water pollution from
animal wastes is indeed a complex issue that involves three major
categories of study and all of their individual ramifications. The
three major points are; (1) determing the volume and charac-
teristics of the wastes that actually reach the water; (2) applying
the applicable control measures to the offending wastes; and (3)
estimating the cost of these control methods for the entire industry.
Although there is no specific discussion of groundwater pollution from
animal wastes in this report, it is recognized that soil pollution may
prove significant in the future. However, for report purposes it is
assumed that groundwater protection can be achieved through proper
design of lagoons, detention ponds and confinement areas.
In studying the situation for this report it became clear that
one valid approach to fully assessing the problem would be to describe
and categorize waste dischargers and then break the animal wastes
issue into several logical sub-elements to be dealt with in the
required detail as time, knowledge, and monetary restrictions permit.
Using these procedures, studies of each sub-element can be completed
individually and later combined with studies of the other sub-elements
to arrive at an estimate of the total cost of abating pollution from
these animal sources. The diagram in Figure 5 shows the major details
of these sub-elements as they are used in the report.
As each component is discussed, i.e., cattle, swine, poultry,
and sheep, the known factors about each one are summarized. This
summary statement covers such things as the pollution potential,
the unanswered questions, and the status of ongoing studies. Because
of the emphasis placed on the cattle industry this year, that section
will be the most comprehensive and will provide the greatest amount of
detail.
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Figure 5
Major Components of the Farm Livestock Industry That Must Be
Analyzed to Estimate Water Pollution Control Costs.
BEEF COWS
FAT CATTLE
DAIRY
DUCKS
BROILERS
LAYERS
TURKEYS
FINISHING
FARROWING
FARROWING AND
FINISHING
CATTLE
POULTRY
SWINE
TOTAL COST
OF ABATING
POLLUTION
FROM FARM
ANIMALS
FINISHING
SHEEP
10
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COMMON CHARACTERISTICS OF ANIMAL WASTE DISCHARGES
To the extent feasible the animal wastes problem will be discuss-
ed in the smallest component part. However, there are some character-
istics that are common to most, if not all, the components and these
will be discussed initially to simplify the discussion and aid in its
understanding. These common characteristics are related to the
frequency of pollution and are defined under the headings of'regular",
"intermittent", "seldom", and "never". This categorization is
important when estimating the pollution potential as well as the
types of control measures that will be required.
A complicating factor in the assessment of animal wastes that
cause water pollution is the variability of waste discharges. In
municipal and industrial situations wastes are usually discharged
on a regular basis. This is not to say that there is no variability
in industrial or municipal waste discharges, but only that there is
basically a day-in and day-out discharge pattern from these sources
with the variability falling mainly in cycles within these regular
patterns. For example, a residential section will dispose of its
wastes daily. However, within any given day there will be high and
low discharges for the group as there will be high and low discharges
on a seasonal basis. Despite such internal variability there is the
daily regularity which allows reasonable estimates to be made of the
volume of waste discharge and makes feasible a continuing operation
for the treatment and disposal of this type of waste.
Animal wastes, on the other hand, are not discharged with the
same regularity on a gross basis. If one considers any waste carried
in a fluid medium from the animal confinement area to a watercourse
as a discharge, then dischargers can be generally classed as regular,
Intermittent, seldom, or never.
Regular dischargers may be defined as those discharging on a
dally basis. Intermittent dischargers are more difficult to define
since they cover the broad range from several discharges per year up
to something less than dally discharges. Dischargers labeled as
seldom are those that have a discharge frequency of around two or three
times per year. Although labeled as never dischargers, those falling
1n this category can have an occasional wastes discharge but only 1n
a very unusual circumstance. For example, floods in areas not
normally subject to flooding, extremely severe rainstorms, or other
similar rare occurrences that result 1n water pollution from the
animal operation are discounted and the discharger is considered as
falling in the never category.
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Regular Dischargers
Those operations discharging on a regular basis may use a variety
of methods to collect and transport their wastes. However, the most
common ones of concern are the swine, dairy, and poultry operations
using water flushing systems, the special cases of duck raising
enterprises, and the animal units in direct stream contact. Although
there are several methods or combinations of methods that might be
used in any given water flush operation, only a single method for
each different type of animal enterprise will be described here.
Before describing a particular type of water flush operation it
will be helpful to point out some of the common reasons for, and
characteristics of, hydraulic or water flushing. Hydraulic flushing
is, by and large, used to reduce labor time in cleaning operations
or to increase the effectiveness of the cleaning operation. These
two factors are, of course, interrelated but either one alone can be
the deciding factor when an operator is considering the feasibility of
installing a hydraulic flush system.
Benefits from water flushing are manifold, but chief among them
are reduction of nuisance problems, reduction in labor costs, or
increased labor efficiency. Nuisance problems are decreased because
of the higher quality cleaning possible and the Increased frequency
of cleaning possible with the use of a water flush system. The
higher quality and increased frequency of cleaning helps to reduce
odor, disease, and fly problems.
Water flushing usually increases the capital investment required
for the enterprise but decreases the amount of labor required for
the cleaning operation. Lower labor costs and decreased death losses
or increased gains attributable to better cleaning can offset some
of the increased capital costs, but, in most cases, the primary attrac-
tion is the enterprise's ability to maintain the same size operating
unit with less labor or to increase the animal capacity without
increasing total labor needed for the entire enterprise.
A common problem associated with water flushing is the inability
of the water to remove the collected debris and manure under certain
unfavorable conditions. These unfavorable conditions may vary from
freezing in the cold climates to drying and packing in the hot
climates. Design and operation problems encountered include floor
slopes not geared to the flush volumes, slopes not designed to
minimize water use, and the use of bedding material that is not
readily flushed by the water system.
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As far as debris 1s concerned, Its flushablllty 1s primarily
dependent upon Us size and compaction. Large chunks of any substance
that will not break up or readily dissolve cannot be flushed satisfac-
torily. Stalks of com, hay, or straw have a tendency to tangle
together and drag during the water flush. Therefore, bedding of a
straw nature 1s not used with a flush system. By the same token, hay
1s not fed In the stall area where it can be dropped in large quanti-
ties and Interfere with the flushing operation.
Unless 1t Is solidly packed or frozen, manure can be flushed with
relative ease. Therefore, to assure that the flushing action Is
effective, It must take place frequently enough to prevent drying and
packing or a buildup too great to be washed away. This usually means
flushings of at least twice a day and often more frequently. Freezing
presents a much different problem In that flushing systems probably
cannot be used In very cold climates unless the entire system 1s
enclosed and, In some cases, at least partially heated. In moderate
climates frequent flushings may prevent hardening of the manure and
resultant poor results from flushing.
In general, 1t can be assumed that operators will try to minimize
the amount of water used 1n the flush systems. When water use 1s
minimized 1t means that the concentrations of pollutants Increase per
remaining unit of flush water. Even If a maximum of water were used
for dilution purposes, the concentrations would still be too high to
allow the wash water to flow directly Into a watercourse. This Is
true because of the sheer volume of wastes produced dally by animal
enterprises large enough to economically use a flush system. The
suggestion that these flushing wastes be placed on the land through
spray Irrigation Is probably valid but care must be taken to assure
that the wastes cannot be eroded Into the watercourse at a later time.
Water flush systems are usually not readily adaptable to most of
the existing farm animal enterprises. In most cases the floor slopes
need to be modified, stall widths and lengths changed, and In some
cases, the location of the pens or buildings will have to be changed
when a flush system 1s Installed 1n an existing facility. In all
cases tanks must be Installed, gutters modified, and a drainage, hold-
Ing and removal system Integrated Into the flush arrangement.
Although there are many problems Involved 1n adapting an exist-
ing facility to a flush system, there are many animal units that can
be so adapted with a minimum of extra problems. In addition, all new
facilities can be designed to accommodate a flush system. Therefore,
1t 1s Important that some helpful criteria be developed to assure that
new flush systems do not contribute to the water pollution problem
and so that existing systems can be modified to abate any water
pollution.
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Description of Water Flushing Methods used 1n
Dairy, Swine, and Poultry Operations
Dairy. Cow milking operations on a large scale may employ a
water flush system that Includes both a milking parlor flush and a
loafing area flush. As the cows enter the milking parlor they are
washed down 1n the area of the udder, either by a spray nozzle or by
hand washing. The quantity of manure that 1s washed off the udders of
all the cows during the operation 1s relatively small but the concen-
tration per unit of water 1s still fairly high. After the cows have
been milked the entire parlor 1s washed down to remove all manure
which had been dropped while the milking process proceeded. In
addition to cleaning up the parlor and milk house proper, the milking
utensils, pipes and other equipment must be washed. In this regard,
many dairy farms utilize a milking parlor and are faced with this
volume of water disposal even though they do not use water flushing as
described 1n the following section relating to the areas where the
cows are kept between mil kings.
In a free-stall setup the animals are kept in a confined area
with sloping concrete floors. The entire arrangement is designed to
assure that the animal feces will be dropped on the floor where they
can be readily washed down. Tanks with drop gates are placed at the
upper end of the sloping pens. A hydraulic head 1s built up when the
tanks are filled with water. At the prescribed cleaning time the
gates on the tanks are dropped and the water rushes out and down the
sloping floors carrying the manure and debris with it. Some observed
flushing operations such as just described use as much as 50 to 60
gallons of water per day per cow to clean these confinement areas.
Even considering a system designed to minimize the amount of water
required, the water use per day would amount to around 20 gallons per
cow with no decrease In the amount of solids removed.
After completing Its flush, the water may be sent into a stream,
a lagoon, a natural or manmade ground channel, or used for Irrigation
purposes. It 1s at this point that water pollution control officials
become concerned with the material collected during the flushing
operation, since 1t may be discharged directly or Indirectly Into
watercourses or 1t may be allowed to sit for some period near the
watercourse and later washed in by water from melting ice and snow,
or from rains. In any case, the pollution load for any receiving
watercourse can be very severe since many of the dairy enterprises
utilizing a flush system will be units with 100 cows or more.
A description of a water flush system used in swine enterprises
will be quite similar to the free-stall housing flush system. However,
the volumes of water used and the method of flushing will vary.
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Swine. Hogs are apparently cleaner by nature than the other
animals raised for food. For this reason, a flush system is more
readily adaptable to a swine operation. In many swine barns the floors
are sloped from the center to the outside edges and the entire floor
is sloped lengthwise. In this manner any liquid in the unit would
tend to move to the outside edge and down to the end of the unit.
Gutters built into the floor along the outside edges of the building
make an excellent channel for the flow of water during the flushing
operation.
In most cases, the hogs will learn to defecate in the channel so
as not to dirty their pens. Therefore, it will usually not be neces-
sary to flush down the interior of the pen although it is easy to use
a hose and wash down this area if the hogs become sloppy. Use of a
gutter in this fashion tends to minimize the amount of water required
and, at the same time, maximize the concentrations of pollutants in the
flush water.
At this point, the problem becomes almost identical with the one
described for the dairy operation, that is, how to collect and dispose
of the flush water in the most efficient manner without causing
pollution problems. The same disposal methods and constraints as
previously described for dairy enterprises also apply to the swine
enterprises.
Poultry* For our purposes, poultry enterprises are considered
in three broad groupings: (1) broilers and layers; (2) ducks; and
(3) turkeys. There is no single management technique currently
applied to all types of poultry enterprises, just as there is no
single technique applied to any of the other animal raising enter-
prises that are discussed herein. However, a brief discussion of
the types of water pollution problems associated with each type of
poultry enterprise and a description of some of the waste handling
systems in use can be useful in categorizing the water pollution
problems caused by the enterprises.
Water pollution as a result of broiler and layer enterprises
can range from the regular to the never categories of discharges
previously discussed. Turkey enterprises will often fit the inter-
mittent discharger category while duck raising enterprises generally
fall into a special type of regular discharger category.
Broiler and layer. Poultry enterprises have probably had more
experience with a water carriage waste handling system up to this
time than any of the other animal enterprises. Here again, the system
was primarily developed to aid in removing the wastes with a minimum
amount of labor and to provide a maximum practicable amount of cleanli-
ness. In other words, the system design did not, in most cases,
consider the broad effects of the wastes upon the environment after
their removal from the animal areas.
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An example of a system discharging on a dally basis would be a
combination of mechanical scraping and water carriage of the wastes
out of the pen area. In this system the water flows through a sloping
gutter during the cleaning operation so that wastes can be scraped
from the floor or dropping shelves Into gutters. Another variation
uses water Instead of a scraper to move the wastes Into the gutter.
This latter method employs the use of a hose and pressure nozzle to
flush the wastes from the floor or dropping boards Into the gutter.
In any case* the principle 1s to remove the wastes from the cages
or pens 1n the most advantageous manner and dispose of the wastes
through some subsequent operation. Such subsequent disposal operations
might Include Irrigation of the effluent, hauling and spreading as a
slurry, or In extreme cases, direct disposal of the wastes Into a
watercourse.
Water flush systems similar to those described for hog and dairy
enterprises can also be used 1n poultry systems although some diffi-
culty may be encountered In assuring that the wastes are adequately
scoured from the floor surfaces. The special problems Involved are
the moisture content of the wastes to be removed and the absence of
scouring particles 1n the waste materials.
Water flush or carriage systems will work equally well for all
of the broiler and layer enterprises, however, climatic factors are
major Influences on the type of waste handling system presently 1n
use. In arid areas a system that takes advantage of natural drying
conditions may be preferable while the most advantageous system 1n
humid areas may be one that uses water as a transport and/or flushing
medium.
Although there may be many disposal systems employed by varia-
tions of the regular dischargers, the only other ones discussed here
are specialized duck raising operations and those operations that
allow their animals free access to a watercourse.
Duck raising enterprises present a problem similar to that of
a flushing operation but the Intent as well as the effect Is different.
In a typical duck raising setup the ducks are grouped along a flowing
channel of water by ages. The result 1s like a staged continuum with
the birds phased along the water channel from birth to slaughter.
The flowing water, among other things, aids 1n the development
of a marketable feather from the bird. At the same time, It carries
the wastes that are dropped in the channel Into a receiving water-
course. In addition to the regular nature of these wastes being
carried by the channel, there Is a problem of slug loads occurring
during rainstorms. Since a large part of the duck's time 1s spent
out of the water, there tend to be sizeable accumulations of droppings
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along the sides of the channel between cleaning operations. During
rainstorms the accumulated droppings are flushed Into the channel
and carried Into the watercourse. The resulting slug can be devastat-
ing but the effect is dependent upon factors such as the number of
ducks, amount of waste accumulation, length of storm, and volume of
water.
From a national viewpoint duck raising enterprises do not consti-
tute a major problem because of the limited number of enterprises
needed to fill the demand for ducks. However, from a local point of
view, the duck raising operations can be a serious problem. Also,
for this report they provide good examples of work that has been done
to abate pollution from animal raising enterprises.
Direct Contact of Animals with Watercourses
Occasionally, animal raising enterprises are set up so as to
take advantage of the watercourse for stock watering and/or cooling.
In such cases the scope of the operation, In terms of number of
animals, usually would fall in the small category.
Fences are used to set off a particular stretch of stream
along with needed grazing or confinement areas for the animals. In
this manner the animals are free to wander within the fenced area
and make full use of the stream for watering or such comfort purposes
as cooling or keeping Insects away. For whatever reasons the animals
use the stream they tend to pollute the water during that use.
The simple process of the animals drinking from the stream,
for example, can cause pollution from sediments knocked Into or
stirred up In the streambed. Of course, 1t must be recognized that
1n most small operations there 1s no measurable pollution produced
in this manner. However, where the concentration of animals Is
heavy, there can be significant sediment problems caused by the
continual dragging of debris Into the stream and the constant mixing
and churning of the bottom muds by the animals' feet. In addition,
If the stream 1s situated so that the animals use It for comfort
purposes or spend significant amounts of time next to it, wastes
dropped by the animals themselves can create sizeable pollution loads.
That 1s, the wastes can be dropped directly Into the stream while the
animals are using It for comfort purposes. This can cause a pollution
load if the numbers of animals are large in relation to the stream
size. On the other hand, If a significant buildup of wastes occurs
on the banks even a small number of animals could place a harmful
slug load of pollution In the stream during a flushing rain.
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Intermittent Dischargers
For the most part, Intermittent dischargers do not deliberate-
ly pollute the water or even knowingly permit conditions that allow
the waters to become polluted. An example of an Intermittent polluter
might be a feedlot operator whose lot 1s hard surfaced and well away
from any stream or drainage course that reaches a stream but who
spreads the manure during cleaning operations on fields that are near
to streams or direct drainage courses. Once the manure has been
spread 1t can then be washed Into the streams by ensuing rains or by
waters flowing from spring thaws. Similar situations could arise for
any animal raising enterprise. The critical factor in these cases 1s
not the production of the manure or the vagaries of the elements but
rather the deposition of the wastes where they are subject to washing
Into a watercourse.
Other Intermittent dischargers Include operators of open
confinement lots that are located so that a heavy rain or series of
rains can wash wastes from the confinement area Into a watercourse.
In these cases the critical factor 1s the location of the confinement
area and the fact that the elements can cause a discharge without any
physical movement of the wastes by the operator of the animal
enterprise.
There are, of course, cases of Intermittent polluters that
deliberately release or dump animal wastes from their enterprise Into
watercourses. In some cases this may amount to loading and hauling
the wastes to the stream. In other cases it may be that the wastes
were contained 1n a pit or other detention system until cleaning was
needed and at that point flushed Into a drainage channel or water-
course.
Another possible Intermittent polluter might be the conscien-
tious operator who Is trying to prevent pollution from his enterprise
but has an under-designed prevention system. This could occur when
a lagoon or detention pond has been built to contain or treat the
wastes but the pond 1s not large enough to hold the water accumulation
from extended or severe rains.
The following examples of animal enterprises that might be
considered as Intermittent polluters will help to clarify how these
operations contribute to water pollution and what possible means
might be used to curb such pollution.
Probably the most common cause, on a purely numerical base,
of water pollution from animal feeding enterprises 1s carelessness.
That Is, on a day-1n and day-out basis most Intermittent pollution
1s caused by operators who do not realize that they are causing
pollution or who think that their contribution to water pollution 1s
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too Insignificant to cause a problem. Such an operator might be one
of the thousands of small feedlot operators scattered throughout
the Midwestern United States. These operators generally feed from
25 to 100 head of cattle on a seasonal basis to provide an outlet
for their surplus labor during the winter months.
The animal feedlot confining only a few head through the
winter will not have much runoff 1n the winter months. However, when
the spring thaws begin there will be substantial quantities of liquids
laden with animal wastes running from the confinement area.
Since runoff will follow a natural drainage path, there Is a
strong possibility that during rainstorms or rapid thawing conditions
the wastes will reach a watercourse. It 1s easy to see that the
prime factors Influencing the amount of such runoff reaching any
given stream are the: (1) size of the feedlot; (2) size of area
draining across the lot; (3) number of animals; (4) surface and slope
of the lot; (5) proximity of the lot to the stream; (6) amount of
rainfall or water stored as 1ce and snow 1n the lot or drainage area
above the lot; (7) terrain between the lot and the stream; (8) dura-
tion and amount of rainfall; (9) condition of the lot prior to the
rain or thaw, Including antecedent rainfall and frequency of cleaning;
and (10) temperature conditions.
Feedlots containing more than the 100 or so animals used 1n
the preceding section as an arbitrary upper limit 1n defining small
feedlots, may also contribute to water pollution. In fact, the same
factors that Influence the amount of water pollution from small lots
Influence the amount of pollution from larger lots. However, the
larger the lot, the more likely that the operator recognizes that
the wastes from his lot can cause water pollution. Thus, It 1s more
likely that he has taken at least some steps to mitigate or prevent
such pollution. For this reason the larger lots are probably Inter-
mittent polluters because of accidental releases or overflows rather
than from lack of understanding and some efforts to avert the problem.
Efforts by feedlot operators to preclude runoff pollution
from their lots have, 1n the past, usually been minimal and often
consisted of diversion ditches, detention ponds, lagoons, more atten-
tion to cleaning the lots and solid waste handling, or some combina-
tion of these methods. Since there 1s no profit for the operator In
providing water pollution control, the efforts to prevent pollution
are minimal and, therefore, the control measures are often poorly
designed.
A more detailed discussion of control methods and cost factors
for water pollution control from feedlots can be found In the "Feedlot
Pollution" section of this report. However, the following review of
the diversion, detention, Irrigation method 1s presented here as an
example of how a large scale feedlot operation can become an Inter-
mittent polluter. Specific types of control measures that might be
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used by a large feedlot operator might Include a series of diversion
ditches 1n combination with a detention pond for holding any runoff.
The diversion ditches are designed to keep water from flowing onto
the lot from other areas upgrade from the lot. The diversion ditches
will usually be built around the upper end of the lot and along Its
sides, with the collected water channelled Into a drainage area away
from the feedlot. The detention pond, on the other hand, is designed
to hold the water that runs off the lot Itself, or from the lot and
necessary driveways, or work areas.
A detention pond in most cases 1s not built to hold a large
accumulation of water over an extended period of time. Rather, 1t
is designed to hold expected rainfall over some given period and is
then to be emptied 1n preparation for the next rainfall. The most
common method of emptying a detention pond is through use of a pump
from the pond through the irrigation system onto land or crops for
ultimate disposal.
Poor design of the pollution prevention system just described
can cause or lead to water pollution through excess runoff overflowing
the pond, or through improper use of the irrigation equipment. In
most cases this poor design 1s a result of the feedlot operator's
efforts to minimize expenditures for pollution control measures.
Cost minimization, in the absence of enforced penalties for pollution,
involves a calculated risk with respect to possible pollution situa-
tions. That is, the system is designed to accommodate about the
median rainfall situation over the years rather than the maximum situa-
tions. As a result, during periods of high or extended rainfall the
system becomes overloaded and water pollution may occur.
Cost data are not available and would certainly vary from
location to location but some generalizations can be made about factors
affecting costs of a simplified diversion, detention, irrigation
control system such as described in the prior discussion. First, as
long as there are no major penalties attached to an occasional pollution
incident, the least-cost control system would eliminate most of the
pollution incidents but would allow extraordinary circumstances to
cause some pollution load. The basic reason for not designing a
system to handle the extreme or unusual cases is the very low return,
in terms of decreased numbers of Incidents occurring, to the feedlot
operator for his increased costs.
Sizing the detention pond, diversion ditches, and irrigation
land areas to accommodate the maximum expected rainfalls, duration
of rains, or frequency of rains will increase costs of construction,
operation, maintenance, and land. Availability of land for pond
purposes and the cost of the necessary added land for maximum protec-
tion may be the prime factors considered when sizing a detention
pond. However, additional factors that must be considered are the
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costs of constructing adequate and sturdy diversion ditches, Increas-
ing the size of the pump-out system, providing a pump-out system that
will operate 1n the rain, and providing enough land so that Irrigation
during or prior to a rain will not lead to water pollution.
Even 1n situations where the detention ponds and diversion
ditches are adequately designed to handle maximum expected rainfall
conditions, the system can still be an Intermittent pollution source
because of the land disposal operation. Just as 1n the case of the
other animal enterprises previously discussed, the final test of the
system 1s whether or not the wastes are finally disposed of in a manner
that will not allow their eventual movement to a watercourse. If the
effluent is placed on the land through Irrigation in high concentra-
tions near a watercourse there 1s little likelihood of complete
decomposition before a rainfall washes 1t Into a stream. Therefore,
the point of Irrigation and the concentration of effluent per unit
of land must be carefully watched to avoid Intermittent pollution.
Deliberate dumping or releases of animal wastes can also be
sources of Intermittent pollution. As the terms are used here,
dumping deals with a solids waste handling method while releases deal
with a liquid or slurry method.
Dumping, although probably Infrequent, occurs when the waste
materials are collected 1n their normal semi-solid to solid state
and mechanically transported to a disposal site. Unlike the normal
spreading of wastes to disperse them, this method dumps the wastes
directly Into a stream or Into a drainage channel to later be washed
into the stream. Dumping appeals to some animal enterprise operators
because it 1s an easy means of disposal and is low 1n cost 1f returns
to nutrient recovery and soil conditioning are discounted.
Releases of liquid or slurry mixtures of animal wastes would
normally come from animal enterprises utilizing pit storage areas
under the animals. Although there are only a limited number of animal
enterprises using pit storage and release systems, they are mentioned
here to provide an additional example of intermittent type dischargers.
It is recognized that not all pit storage areas are cleaned by
releasing the accumulated slurry. Rather, most pits are cleaned by
pumping the wastes into special tank wagons for transportation to a
disposal area where the wastes are spread on or incorporated into the
soil.
The basic advantages of pit storage are temporary storage and
the fact that no labor is needed for the cleaning operation during
the accumulation period. There are also many disadvantages to pit
storage but these will be discussed in a later section of the report.
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The temporary storage and periodic release systems are gener-
ally used in conjunction with a lagoon or other similar treatment
method where the wastes can be biologically degraded. When using
this combination system the wastes are released from the pit and
channeled into the lagoon. The pit is then washed down and the
remaining wastes flushed into the lagoon for treatment. From a
water pollution control point of view the major disadvantage with the
pit-lagoon combination systems is that a lagoon can be by-passed or
not installed at all. As far as the operator of the enterprise is
concerned, his prime concern is simplifying the storage and cleaning
operation and the disposal of the cleanings with a minimum of effort
and cost.
Most enterprise operators consider a lagoon as an unnecessary
added cost that they could do without if the wastes can be accommodat-
ed by a stream or dispersed far enough down the drainage channel to
prevent severe odor or disease problems. Therefore, the pit releases
might be direct to a watercourse or to a drainage channel from which
they would eventually be washed into a watercourse.
An example of an intermittent release from a covered confine-
ment animal enterprise might be one that stores the wastes outside
for some period before they are moved to disposal sites. In this
case rainfalls can leach pollutants from the piled wastes and wash
them into watercourses. This type of pollution can be extremely
deceptive since the leaching process takes out salts, minerals, and
nutrients that are invisible to the human eye but very harmful to
the watercourse that they enter.
Seldom Dischargers
The discharger that is labeled as seldom in this report is a
somewhat special case in that he either has virtually controlled all
the wastes discharged from his operation, or he is situated where
there is only an occasional climatic phenomenon that can cause his
operation's wastes to contribute to water pollution. Some examples
of dischargers that fit the seldom category are: feedlots with control
facilities sized to handle almost all rainfall situations; lots or
waste disposal areas that are well away from streams so that only very
heavy rains can cause the wastes to be washed into a watercourse;
and systems that are cleaned only once or twice a year but the wastes
are disposed of in an area where they can easily be washed into a
watercourse.
There is little essential difference in setup between a
feedlot classed as intermiltent and one classed as seldom. The only
differentiating factor between intermittent and seldom is the matter
of degree. Therefore, the same sized feedlot could be in either
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class with only slight modifications of such factors as the size of
the detention pond, the lot slope or surface, location of the lot, or
the point of ultimate waste disposal.
Feedlots with control facilities sized to handle most climatic
conditions can still be occasional sources of water pollution. In
such cases the size of the control or treatment facility is usually
large enough to handle all but the most severe rainfalls or thaws.
However, there are always unusual storms that take place during some
years and these storms can cause an overloading of the ponds, lagoons,
or diversion ditches. Storms severe enough to cause the system's
capacity to be exceeded may occur several times in any given year or
may not occur at all in some years.
The following examples of a moderate sized beef feedlot with
around 1,000 head on feed at any one time shows the essential charac-
teristics that place a discharger in the seldom category. In this
example it is assumed that the lot and necessary additional ground
areas were shaped to provide drainage from the lot to the detention
pond as well as drainage away from the lot for water from outside
sources.
Similiar to the feedlots discussed previously, the categorization
of this example lot depends upon how near the design size of the
control system is to the maximum runoff condition expected over time.
Here again the operator of the feedlot considers the return (amount
of pollution controlled) that can be expected for any given investment
in control facilities. The investment can range from minor temporary
diversion ditches to full scale diversion ditches and a detention pond
sized large enough to hold runoff from the heaviest or most extended
rainfall or thaw on record for the area. In the first case the
discharges occurring after installation of control measures are
frequent enough to class the operation as intermittent, while in the
latter case there would be no discharge and the operation would fall
in the never category.
A discharger with control facilities will usually be in the
seldom category if his investment falls in the high end of the control
range. In this example the operator has invested at the high end of
the range for control facilities. However, he realizes that there
are years in which the rainfall intensity of a given storm can create
a volune of water greater than the diversion ditches can handle and
therefore, some of it can flow across the lot and fill the detention
pond at a faster rate than the pond was designed for. He also realiz-
es that there may be other years in which a continuous or nearly
continuous rainfall condition will prevail for an extended time period
so that the pond will reach overflow stage before conditions permit
the pump-out operation to be completed. In each case the frequency
of overflow depends upon the maximum expected condition that the
system is designed to accommodate.
23
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A feedlot located a considerable distance from any watercourse
or a feeding enterprise with a low density of animals per unit of
land are other examples of possible occasional dischargers that can
be classed as seldom. These situations are similar to those just
discussed concerning operation with slightly undersized control
facilities. That is, the occasional pollution is dependent upon or
caused by unusual weather conditions.
Especially heavy rains or rains of an extended duration can
dissolve more wastes and carry them further distances than the light
or moderate rains of short duration. The result of such heavy rains
is more total wastes being moved to the watercourses. However, in
this case, as in the cases of all other seldom and intermittent
dischargers, the final test of the system is whether or not the
discharges cause water pollution. In other words, it is possible
for an enterprise to be subject to an occasional discharge without
the discharge resulting in any measurable pollution. If the discharge
is never large enough or concentrated enough to create any measurable
pollution load, then the enterprise would be classed as never.
Never Dischargers
It may be helpful at this point to give a couple of illustrations
of occasional dischargers that are classed as never in order to
provide a better understanding of the difference between them and the
dischargers labeled as seldom or intermittent. Lots with control
systems that are only slightly undersize are seldom subject to an
overflow condition which means that several pollution mitigating
factors occur before the overflow. First, the major portion of the
wastes that can be washed away have already entered the pond and the
settlcable solids have started their downv/ard movement. Second, more
dilution has occurred during the pond collection process. Third,
flows in the watercourse have increased. Fourth, the major portion
of the rain is over and the amount of overflow is minimal compared
with the amount of total runoff that occurred. The effect of all
these mitigating factors may be to reduce the waste discharges to a
nonmeasurable or insignificant amount.
Essentially the same change in discharge characteristics takes
place when heavy rains move greater quantities of wastes further
distances. In this case the very things that cause greater movement
also mitigate the effects of this movement. That is, high rainfall
increases the dilution of the wastes as it moves over long distances,
and the longer movement permits more settling and filtering of the
wastes. Of course, many factors are involved in whether a runoff
situation will cause pollution. Among these factors are: slope
and condition of the lot prior to the rain; amount of other surface
water entering the same drainage channel; and distance and terrain
between the lot and the watercourse.
24
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Summary of Classes of Dischargers
The previous discussion has delineated animal enterprises in terms
of their frequency of waste discharge to watercourses. The four
classes used in this delineation are: (1) regular; (2) intermittent;
(3) seldom; and (4) never. Along with each class term was a defini-
tion of the term and several examples of dischargers falling in that
class.
For the purposes of this report it is important that the distinc-
tion between each class be understood. These differences are impor-
tant in conceptualizing the animal waste problem and in comprehending
the wide variety of opinions on the significance of animal wastes
with respect to water pollution.
Estimation of future control needs and the costs of these needs
will depend upon understanding these different types of dischargers
and what their needs are. It is useless to include a never dis-
charger in any estimation of future control needs and at the same
time it is important to decide what the needs of the seldom dischargers
are. Solutions to the pollution problems of the intermittent
dischargers may very well be different from those solutions applicable
to the regular discharger. In other cases the solution may be to
bring the intermittent discharger's operation to the same level as
the regular discharger and then add the applicable water pollution
control solution for regular dischargers to the intermittent opera-
tion. In any event, there are undoubtedly other ways to classify
waste dischargers, but use of this method will aid in setting up and
carrying out future studies of control needs and costs.
This report focuses upon the regular and intermittent dischargers
as sources of water pollution because of the high marginal reduction
in pollution load possible through abatement of pollution from these
sources. Future focus will be on specific types of uncontrolled
enterprises to ascertain how they now operate and contrast them with
similar enterprises using adequate control systems. Also included
will be discussions of experimental control methods or handling
methods where applicable information is available.
25
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CATTLE
For the purpose of assessing the water pollution potential of
animal wastes, the cattle industry can be divided into three major
sectors. First is the beef cow sector where cows are kept for the
purpose of producing calves for the feeder market. These calves are
sold to the second sector which fattens them to marketable weight and
sells them to packers who ultimately market them as dressed beef.
The third sector is the dairy industry which keeps cows for the
purpose of producing milk and providing replacement milking stock.
Although there are specialized operations that do not fit specifically
into any one of the three segments mentioned, these segments are
broad enough to cover most of the standard operations found in the
industry.
A separate review of each of these segments is necessary because
of the different ways in which the animals are confined and fed and
because of the differing trends that may develop for each segment.
Such variable factors as feed, confinement, and changes in numbers
of animals affect the amount of pollution, present and potential, as
well as the types of controls, changes in handling methods, and treat-
ment methods that may be needed.
Beef Cows
Beef cow herds can be found scattered throughout the various
States, but the greatest production of feeder calves comes from the
States of Kansas, Missouri, Montana, Nebraska, Oklahoma, South Dakota,
and Texas. Additional heavy production areas are found in California,
Iowa, and Mississippi. Map 1, shows the January 1, 1969, concentra-
tions by State of beef cows two years old and older kept on farms.
Because these cows are prime sources of feeder calves, this map
indirectly indicates the areas of most probable sources of pollution
from beef cow operations. However, historical beef cow operations in
these areas of heaviest production have tended to be of a range type.
Calf production under range conditions means that there are factors
operating which mitigate the water pollution potential of wastes
produced by the cows and calves.
An important consideration in using range land for calf production
is assuring a continuation of the grass supply over the years. There-
fore, the cow and calf population per acre are geared to the number
of animal units the grazing land can support without damaging the
grass. Under most circumstances this concern for the grass results in
two major pollution mitigating factors. One factor is a low density
of animal units per acre of land. The second factor is the waste
retention characteristic of grassland.
26
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Map 1
Number of Beef Cows Two Years Old and Older Kept on Farms, by State—January 1, 1969.
ro
-^
Numbers shown in each State
represent thousand head of
beef cows.
Shaded area identifies States with over
one million head of beef cows on farms.
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As is discussed in more detail in the beef feedlot section,
animal density per acre can be misleading when assessing waste poten-
tial. That is, up to a critical point additional animal units may
add very little to the pollution potential; at the critical point
each additional unit adds all its wastes to the potential, while at
some point well beyond the critical point each additional unit adds
less and less to the potential.
As far as range calf production is concerned, the critical point
is never exceeded intentionally because it coincides with the grass
preservation policy. Therefore, there will be little accumulation
of waste since the biological degradation of the wastes must occur
at a rate approximating the rate of waste deposition. By the same
token, the grass tends to counteract the waste transport effect of
rainfall by slowing and catching the wastes near the point of deposi-
tion rather than allowing their free flow to a watercourse. In such
situations it is unlikely that water pollution is much of a problem
on other than a particular case basis.
On the other hand, there are areas which are increasing their
production of beef feeder calves and are doing so in more confined
situations. As a result, the animal concentrations per acre of land
tend to be much higher, especially during certain seasons of the year.
As the concentrations of animals per acre of land increase, the
likelihood of water pollution occurring also increases. This increas-
ed likelihood of water pollution can result from the concentrations
surpassing the critical point or from a significantly higher critical
point because of extremely favorable pasture conditions.
Based on the foregoing overview of the beef cow industry, it
appears that we need to concentrate our efforts on projecting the
trends of the industry as to location and concentration of animals.
This information, coupled with the results of studies under way on
determining the amount and characteristics of runoff that occur in
pasture situations or in concentrated confinement situations, will
provide two parts of the base necessary for estimating the cost of
controlling water pollution from beef cow herds. Other necessary
parts of the base are types of control measures applicable and their
costs.
In light of the small likelihood of beef cow herds being the source
of significant water pollution on a broad scale at this time, the
emphasis on determining costs associated with water pollution control
should be placed on some other segment of the cattle industry for the
near future. This 1s particularly true since the research being done
in the other animal areas can be transferred on a case-by-case basis
to handle individual pollution problems in the beef cow area.
28
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Fat Cattle
The fat cattle industry is a major source of beef for human con-
sumption. Fat cattle can, for our purposes, be considered as coming
from two sources—concentrate fattened and grass fattened. Of the
approximately 34 million head (Figure 6) of cattle and calves now
slaughtered annually, around 80 percent come from fat cattle opera-
tions. Out of the estimated 28 million head of fat cattle slaughtered
annually in recent years, about 23 million were marketed out of
feedlots. The remainder, although not a precise estimate, can be
considered as an indicator of the grass fattened cattle.
Grass fattened cattle, as the name implies, are those that are
raised to market weight under pasture or range conditions where the
main feed is grass with supplemental feed fed only as required.
Concentrate fattened cattle, on the other hand, are usually fed in
confined areas where the concentration of animals is such that grass
cannot grow or is too sparse to provide adequate feed for the animals.
In such cases the cattle must depend upon feed brought in by the
operator of the feedlot. The feed brought in may be a concentrate
such as corn, maize, milo, or similar product. In addition, there
may be other concentrates, proteins, or minerals added to or mixed
with the basic ration. The main objective is to use a ration that
is least costly in the context of the particular feeding operation.
This often means a ration that produces a high rate of gain per
animal and consequently a relatively rapid turnover of animals
through the lot.
The distinction between grass fattened cattle and concentrate
fattened cattle is important to this report only because of the differ-
ing potential for water pollution that each type of operation poses.
The grass fat cattle generally can be considered as minimal sources
of water pollution. The remainder of this section is devoted
to a detailed discussion of the pollution potential of various types
of fat cattle operations. The schematic diagram in Figure 7 shows
the breakdown of the operations that will be discussed in light of
each segment's water pollution potential.
Animal Wastes That Cause Water Pollution
At this point 1t may be helpful to discuss the general aspects of
water pollution resulting from climatic factors acting upon uncovered
animal fattening operations. Since these climatic factors affect all
types of uncovered animal raising operations, the points .discussed
here are also referred to in other sections of the report. However,
the major source of potential pollution from animal wastes is the
cattle fattening industry, therefore, these general aspects are most
appropriately discussed at this point.
29
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Figure 6
CO
o
CO
0>
36
34
32
30
28
26
24
ot
Cattle Slaughter, 1959 through 1968.
1959 1960
1961 1962 1963 1964 1965 1966 1967 1968
SOURCES: Livestock and Meat Statistics-Supplements for 1967 and 1968 to Statistical
Bulletin No. 333, U.S. Department of Agriculture, Economic Research Service,
Statistical Reporting Service, and Consumer and Marketing Service, Washington, D.C.
-------
Schematic Drawing of the Components of Fat Cattle Operations
that Affect the Water Pollution Potential of the Animals.
Grass Fattened
Cattle
High Density of
Animals Per Acre
Low Density of
Animals Per Acre
Climate
Climate
Fat Cattle
Figure 7
Animal Numbers
-Large
Feedlots
Animal Numbers
-Small
Broken Line Signifies a Prime
Factor Affecting the Amount of
Pollution Generated.
Climate
Climate
31
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It can be said, from a water pollution prevention standpoint only,
that this report's concerns are the amounts and characteristics of
animal wastes that reach watercourses. Although, there are other
mitigating factors, for our purposes this general assumption is
adequate.
In most instances, cattle fattening enterprises can be categorized
within the ranges of intermittent, seldom, and never. A large number
fall into the intermittent category but there is no estimate of the
actual numbers that fall into any of the categories at this time. As
more information is accumulated regarding runoff from confinement areas
under varying circumstances and as inventories of the animal enter-
prises become available, it will become possible to estimate the
number and size of the enterprises falling in each category.
Climatic factors such as precipitation and temperature are the
prime causes of intermittent type discharges. In other words, rain
falling on unsheltered animal confinement areas causes a runoff of
the wastes from the areas. Likewise, temperature has an effect
because it can solidify the wastes and prevent their runoff or it can
prevent their absorption into the soil and thereby permit future
runoff to occur.
A general formulation of the water pollution potential of any
given animal enterprise would show that the potential is related to
many factors interacting with each other. The actual pollution is
then a result of outside factors acting upon this potential. The
factors affecting the potential are: (1) numbers of days the animals
are confined; (2) daily quantities of wastes produced per animal;
(3) number of animals; (4) characteristics of the wastes; (5) amount
of daily degradation of the wastes; (6) amounts of waste removed
by runoff; and (7) amounts of waste removed by cleaning operations.
A simplified formula such as the following formula which measures the
pollution potential in terms of population equivalents can be used to
illustrate the interaction of the seven aforementioned factors.
P = En (AC Tc) - (Cr + Rr)
Where:
Tc = Numbers of days confined
Wa s Pounds of wastes produced per animal per day
Ac = Number of animals confined
Rr - Pounds of waste removed by runoff
Cr = Pounds of waste removed by cleaning
En » Population equivalent, net waste quantity produced
per animal daily where;
32
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En = ("a • °d) - (Do)
0.17
Where:
Ojj = BOD per pound of waste
DQ • Degradation or satisfied daily BOD (estimated)
0.1/ « Standard 5-day per capita oxygen demand of
domestic sewage
P = Total water pollution potential in population
In uncomplicated terms, this formula determines the BOD of an
animal's daily wastes and deducts from that the estimated average daily
decomposition per animal (in BOD) to arrive at a net oxygen demand per
animal per day. This net oxygen demand is then converted to a popula-
tion equivalent and used to convert the net animal days to a popula-
tion equivalent for the entire period of wastes accumulation. Net
animal days are computed by multiplying the number of animals confined
by the number of days in confinement and deducting from the result
the number of animals equivalent to losses in waste resulting from
runoff and cleaning operations. In other words, the BOD of the total
wastes produced minus the BOD in losses due to degradation, runoff
and cleaning yields a net wastes available figure in terms of oxygen
demand. The net wastes figure is then converted to a population
equivalent which is the maximum potential pollution of the confine-
ment area expressed in terms of BOD equivalent of human wastes.
In summary, then, the maximum water pollution potential is
related'to the waste production per animal, maximum number of animals
in the confinement area, days confined, frequency of cleaning, climate,
waste degradation, and waste characteristics. On the other hand,
actual pollution will be affected by factors such as temperature,
rainfall, surface area of confinement pen, slope of the area, texture
and materials mixed with the wastes, type of lot surface, and manage-
ment practices. In other words, actual pollution will not be equiva-
lent to potential pollution under most conditions. An individual
exception to such a statement would be a lot where the surface had been
recently cleaned and a flushing rain cleans the lot surface depositing
the entire amount of accumulated wastes 1n a watercourse. However,
over a longer-run period of time the actual quantity of animal wastes
reaching watercourses will always be substantially less than the
potential quantity.
33
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On a case-by-case basis it is the amount of pollutant that
actually reaches a watercourse that determines the extent of the pol-
lution. However, even in these cases there is a certain amount of
runoff that carries pollutants in concentrations too small to have a
measurable pollutional impact on the water. That is, during certain
rains the dilution factors of the rainfall and the receiving waters
offset any pollutants carried from the lots.
On a gross basis the amounts of pollutants reaching watercourses
are not measures of actual pollution but only measures of the upper
limits and, at best, indicators of the problem. Conversely, on a
case-by-case basis the amounts of pollutants reaching a watercourse can
be related to stream flow and other dilution factors to obtain a good
estimate of pollution potential. Despite these limitations it is
important to understand the general behavior of animal wastes during
runoff conditions in order to broadly categorize the various sizes,
types, and locations of animal operations. The runoff behavior of the
wastes will also have an effect upon the costs of containment or
treatment facilities that might finally be required.
Factors affecting runoff of potential wastes
Many of the factors affecting the amounts of wastes removed from
the total potential wastes contained on a feeding area during a speci-
fic runoff condition have been mentioned previously. They include such
diverse items as: lot slope; climate; lot location; general terrain;
lot surface; waste characteristics; and management practices. Although
there is some empirical information on wastes runoff, there is a decided
lack of information on the runoff under varying combinations of the
factors just enumerated. However, studies under way, such as the ones
sponsored by FWPCA at Texas Technological College; Kansas State
University; and North Carolina State University, will add significantly
to the body of knowledge on wastes runoff.
The present state of knowledge on feedlot runoff is adequate
to use in making some general statements regarding the runoff poten-
tial and in categorization of the animal feeding operations. For
example, as cattle density per unit of land increases past a critical
point, runoff pollution per animal decreases. Also, cleaning may
very well increase the actual pollution contained in runoff from the
lot, depending upon the season, lot surface, and frequency of cleaning.
Actual runoff potential from a given lot over time increases to a
certain point and then levels off with no further increase in poten-
tial for actual runoff during the remainder of the accumulation
period. Each of the previous statements is based upon the simple
premise that once wastes have accumulated to a certain point, no run-
off will occur during light rains and runoff occurring during heavier
or longer rains will only remove some upper portion of the accumulated
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Figure 8 depicts a rough approximation of how the concentration
of animals per unit of land affects the average amount of pollution
per animal that is washed from a confinement area by a given amount of
rainfall. Reading the curve from bottom to top the general interpre-
tation is that a certain number of animals must be present before any
pollution occurs. Then, as the density nears the critical point, the
pollution level rises rapidly followed by an approximate unit increase
for each added animal or decreased land area until the vertical ac-
cumulation point is reached. From the runoff depth point and upward,
in terms of animal density, the average pollution per animal decreases
because only a maximum amount will erode from a given sized lot during
any specified rainfall. The curve shown in Figure 8 is not meant to be
used for comparative purposes and is not drawn to scale so that no
inferences should be made from the curve as to specific relationships
between numbers and quantities. The figure's sole purpose is to give
some visual idea of how animal density affects pollution. The follow-
ing explanation of the terms used in Figure 8 also provides the reason-
ing that went into development of the visual representation.
Reason alone tells us that one animal standing in the middle of a
100 acre pasture is not a source of water pollution. The basic reason
behind this conclusion is that most of the waste would not be washed
out of the grass and into a watercourse. Additionally, even if the
animal was very close to a stream, the dilution of the waste by all of
the water rushing off the entire 100 acres would render the pollution
insignificant, if measurable.
Extention of this reasoning leads to the conclusion that as the
density of animals increases, a point will be reached where the pollu-
tion is measurable. As animal concentration continues to increase, the
effectiveness of grass as a trap and filter decreases. When the densi-
ties approach the critical point no cover remains on the soil. Thus,
the trapping and filtering effect on the grass has disappeared. From
the critical point until a vertical accumulation of undecomposed wastes
begins, increasing densities raise the total pollution concentration
but have little effect on the average quantity of pollutant per animal.
The vertical accumulation of wastes is an important point to
understand since it is this factor that causes the average pollution
per animal to rise faster than the additional concentration of animals
would indicate. That is, in a situation where animals are added to a
specified size feedlot, each additional animal would not be expected
to add to the average amount of pollution per animal. However, when
the wastes are allowed to accumulate, the amount of accumulated wastes
can be washed out by a rainfall thereby raising the average amount of
pollution.
35
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Figure 8
Graphical Description of Pollution Per Animal
Contained in a Given Rainfall Runoff.
No. of Animals
Per Unit
of Land
Increasing
**••. Runoff
**> depth
,»•
..** point
/Accumulation
point
• Critical
; point
• Increasing
.^ Pollution Per
Animal in a Given
Rainfall
36
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Any given amount of rainfall on the same lot under the same condi-
tions will remove about the same quantity of wastes from the accumula-
tion. Therefore, when accumulated wastes reach the maximum depth of
runoff erosion, additional accumulation will not add to the amount of
waste of pollutants carried away during a given rainfall. As a result,
once the runoff depth point is exceeded the average pollution per
animal decreases as the density of animals increases. The vital concept
that applies to this discussion is that the runoff depth point is for
a given rainfall and that heavier or extended rainfalls have deeper
runoff depth points and vice-versa. Other factors affecting the runoff
depth point are temperature, lot condition, slope of the lot, intensity
of the rainfall, and type of wastes.
Data collected, analyzed and published by Miner et al. I/detailed
the wastes characteristics of feedlot runoff and discussed the factors
affecting runoff concentrations. It was found, for example, that the
strength of the runoff from the experimental lots increased with
increasing temperature, increasing moisture content of the lot, and
decreasing rainfall intensities. Other variables, although possibly
relevant, were not tested in this limited experiment.
The preceding discussion of the effect of rainfall on animal wastes
in an unsheltered situation leads to several conclusions abut fat cattle
operations as shown in the schematic drawing of Figure 7. An initial
conclusion is that range fattened cattle represent a much smaller
pollution problem than feedlot cattle, both in numbers and in actual
runoff pollution per animal. Also, as density of animals per acre
increases in a range situation, the likelihood of actual pollution
occurring also increases. Finally, it can be concluded that a more
detailed analysis of the numbers of animals and their locations on a
broad climatic base can be productive in developing estimates of actual
pollution from which estimates of control costs can be formulated.
1} Miner, J.R., Fina, L.R., Funk, J.W., Upper, R.I., and Larson, G.H.,
"Stormwater Runoff from Cattle Feedlots". Management of Nine Farm
Animal Wastes (Proceeding National Symposium, May 5,6, and 7, 1966)
American Society of Agricultural Engineers, St. Joseph, Michigan.
37
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GRASS FATTENED CATTLE
Although there are several million cattle fattened annually under
pasture or range conditions, the wastes produced by these animals have
a minimal water pollution potential. The critical points, as discuss-
ed in the prior section, are seldom exceeded in grass fattening
operations. That is, the animal densities per acre are usually light
enough to preclude any water pollution unless the animals are in
direct contact with the stream. Even in cases where the animal
densities approach the critical point there is some effective filtering
and trapping of the wastes by the grass. Additionally, there is
little undegraded material accumulating to be washed off in slug
quantities.
Low Density
Grass cattle fattening operations that have animal densities well
below the critical point do not require early emphasis on estimation
of their water pollution control costs. The basic problem with the
low density operations is assuring that the animals are not in direct
contact with the water. In almost all cases the control measures and
their costs will be unique and general cost estimates for keeping
cattle from water contact will not be applicable.
Some operations may require considerable fencing to keep the
animals from the water and may also require supplemental water supplies
for the cattle. The control costs in these cases would be fencina
costs plus water piping, storage, and pumping costs. In other cases,
there may be only limited access to the water and fencing would be a
minor cost while water provision might be a more substantial cost. In
any case, as inventorying and more refined assessments of water pollution
under range conditions become available, there will be a stronger
base from which to estimate the water pollution control costs associat-
ed with such operations.
High Density
Grass cattle fattening operations with heavy animal concentrations
are more likely sources of potential water pollution than are the low
density operations. As the animal densities of the operations approach
the critical point, potential pollution increases along with the
probability of actual pollution occurring. This report is, of course,
concerned with the actual pollution aspects of the fattening operations
although potential pollution can be an indicator of the magnitude and
the location of actual pollution.
38
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High density operations have actual pollution problems similar to
the low density operations in those situations where the animals are
in direct contact with the water. Additionally, the high density
operations have more wastes per acre subject to runoff and as the
densities approach the critical point, these wastes have less and less
grass available to trap and filter them.
There is somewhat of an anomoly in discussing densities since the
densities will vary largely according to the ability of the land to
support the animals. Therefore, increasing densities do not necessar-
ily lead to increased pollution. Rather, the densities must always be
related to their critical point before any conclusions about their
potential or actual pollution can be drawn. High densities on grass-
lands with high critical points may not add significantly more to water
pollution than low density operations on grasslands with low critical
points.
As far as grass cattle fattening operations are concerned, their
animal densities are closely related to climate. In order for high
densities to be practical the rainfall must be adequate to support a
heavy growth of grass. However, the reverse is not necessarily true.
That is, an area producing lush growths of grass may or may not be an
area supporting large numbers of grass cattle fattening operations.
Broadly speaking then, water pollution from high density cattle
operations is influenced by interaction of the following factors:
(1) higher densities resulting in more total wastes production per
unit of land; (2) heavy grass growths are required to support the
high animal density; (3) adequate rainfall is required to produce the
lush grass; (4) lush grass growths tend to trap and filter more of the
wastes during runoff conditions; (5) higher rainfalls tend to wash
more of the wastes from the land but they also provide some additional
dilution of the wastes. It is easy to see that the interaction of
these factors prevents any purely judgemental assessment of the amount
of actual water pollution occurring as a result of high density grass
cattle fattening operations. However, the mitigating factors are
important enough to provide a base for the conclusion that the amount
of water pollution from these animal sources, although not quantifiable
at this time, is much less than that from sources such as feedlots
where the critical animal density point has been surpassed. Like the
low density operations, better estimates of the actual pollution
resulting from high density operations can be made after work is
completed 1n measuring runoff and stream monitoring under varying
pasture loading conditions.
39
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In terms of overall importance in the total water pollution
picture, high density cattle fattening operations must rank above the
low density operations. However, a major thrust of the water pollution
control efforts should not be directed at this segment until the more
direct and larger pollution sources have been located and controlled.
This is not to say that the individual cases of water pollution should
not be located and controlled whenever possible. Rather, it means
that on a national scale with limited resources, these resources should
be used to attack general problems with the greatest potential for
high marginal reductions in pollution loads. Then, as these primary
pollution sources are controlled, the early ongoing research on the
lesser problem areas can be brought to bear on solving such problems
at a minimum cost.
40
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CONCENTRATE FATTENED CATTLE
Cattle fed in the limited confinement feedlot areas annually
produce billions of pounds of wastes. The handling (removal and
disposal) of these wastes presents the feedlot operators with major
labor, equipment, and logistical problems. Additionally, these
wastes represent potential water pollution sources of a serious nature
and magnitude.
Actual observations have shown that many feedlots are located on
or very near to streams. The close proximity to watercourses and
the slope of these lots force any significant rainfall to carry heavy
slug loadings of BOD, COD, and other harmful components of the wastes
into the streams. In the midwestern areas where manure collects on
the lots during the winter when little decomposition takes place, the
slug loads can be especially heavy during the spring rains and thaws.
Although quantities or frequencies of actual pollution from animal
wastes are not known, evidence of such pollution and the damages it
can do may be found in the number of reported fish kills attributed
to animal wastes pollution.
Table 1 shows the number of reported fish killed during the year
1964 through 1968 as a result of animal wastes entering watercourses
in lethal concentrations. Although these figures probably do not tell
the complete story, they are useful in showing that animals can and
do contribute to water pollution under certain conditions. Since the
fish kill figures shown in Table 1 represent only reported kills that
were traced to animal wastes,pollution, the true number of kills is
likely much higher. Also, these figures provide no indication of the
amount of stream degradation which occurred but did not result in
outright or traceable fish kills.
Besides the obvious pollutional hazards of feedlot wastes such as
fish kills, it has been demonstrated (Miner et. a!.) that feedlot
runoff is a source of high concentrations of bacteria. Since bacteria
are normally considered as indices of sanitary quality, their presence
in high concentrations can result in that particular section of water
not meeting the accepted water quality standards.
41
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Table No. 1 — Number of reported fish kills and total nunber
of fish killed as a result of manure, silage, or
feedlot drainage, 1964 through 1968.
Number Reporting Number of fish killed
1964 26 1,156,885
1965 25 616,882
1966 34 1,040,993
1967 37 1,268,137
1968 19 35,238
Source! Pollution"Caused Fish K1 lTs~Federal Water Pollution ^ontroT
Administration, United States Department of the Interior, Washinaton,
D. C.~ 1964, 1965, 1966, 1967, 1968.
Number of Feedlots
The number of feedlots marketing cattle in 1968 came to 208,596.
These feedlots marketed over 23 million head of cattle, with almost
half of the marketings coming from lots with capacities of over 1,000
head. In terms of our definition, almost all feedlots have animal
densities that meet or exceed the critical point. In fact, most of
these lots will exceed the accumulation point as well as the maximum
runoff depth point. Therefore, feedlots are likely sources of water
pollution deserving further analysis and enumeration based upon such
analysis.
Discharge Frequency
The frequency of discharges from feedlots can, in most cases, be
categorized as seldom to never. The remainder of the cases generally
fall into the intermittent category although it is possible to have
some feedlots regularly discharging wastes.
Across the country the prime factor affecting both frequency of
animal waste discharges from feedlots and the amounts of such discharges
is climate. Of course, for any particular lot the effect of climate
can be modified by management decisions, lot location, and the general
topography of the lot and surrounding areas. In general, however,
climate is the major factor to consider in determining needed waste
control facilities and is, therefore, an indirect determinant of costs.
42
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Climate
Climate basically affects the runoff from a feedlot through an
interrelationship of temperature and precipitation. However, climate
also influences the number of animals fed by a single enterprise,
concentration of animals within a feedlot, location of the lot, and
the amount and type of shelter provided for the animals. All of these
factors influenced by climate also affect the amount of runoff that
can be expected.
With some variation based on intensity and temperature, runoff
from a feedlot varies directly with the amount of precipitation.
That is, the more precipitation, the more runoff that can be expected.
Even precipitation in the form of snowfall can cause runoff during
thawing conditions.
For any specified rainfall, the concentration of wastes and
therefore the total amount of wastes removed from the lot varies
inversely with the intensity of the rainfall. High intensity rains
create less total pollution than low intensity rains depositing the
same volume of precipitation. The effect of temperature on runoff is
basically found at the extremes of hot and cold. If the temperature
causes the wastes on the feedlot to be in a semi-frozen to frozen state,
the waste runoff is retarded significantly. Similarly, if the temper-
ature is high enough along with proper moisture and wind conditions,
to promote rapid drying on the feedlot surface, the wastes dry out and
become packed into a solid state resulting in decreased runoff from
any given amount of rainfall. On the other hand, frequent rains,
humid conditions, and high animal densities tend to keep the lots
moist and thereby increase the amount of wastes runoff from a given
rainfall. The increased runoff and concentration of wastes in the
runoff result from a lower absorption capacity of the wastes on the
lot and because the wastes are in a semi-liquid state which eases their
pick-up by the runoff water.
The preceding summary of the major effects of climate on runoff
from feedlots and the amount of wastes contained in such runoff is
not meant to be at all inclusive. Rather, it serves to show that
groupings of feedlots by major climatological variations have relevance
in assessing the overall water pollution control problems associated
with feedlots.
Management decisions concerning the number of cattle to feed,
animal densities to maintain, type of shelter to be provided, and the
location of the feedlots are largely influenced by climatic factors.
Favorable climates, particularly those without extreme cold or high
precipitation levels, are conducive to large scale feedlot operations.
In the favorable climates the most important limiting factors affect-
ing size are feed supplies, availability of feeder animals, and to
some extent, high temperatures.
43
-------
Cold areas with high precipitation levels are especially unfavor-
able to the operation of large-scale feedlots. During cold v/eather
the precipitation may well be in the form of snow or sleet. In either
case, both the cold and the precipitation place added stress on the
animals as well as on the men and equipment. The result of such added
stress is lower gains per animal relative to feed consumed, higher
death losses, fewer animals handled per man, and increased equipment
costs. Overall, the greater demands on management and increased costs
in such situations usually restrict the size of the feedlot operations.
The number of animals per unit of land is also influenced by
climate. In the areas of heavy precipitation, animal densities on
unsurfaced lots must be decreased in order to maintain reasonable lot
conditions. Heavy animal densities during wet periods, especially
during spring thawing conditions, can create a quagmire of mud and
wastes in the feedlot. Conversely, animal densities can be quite
heavy in dry climates without creating undesirable lot conditions.
Poor lot conditions increase animal health problems, adversely
affect feeding efficiency, and add stress to men and equipment. In
order to overcome the adverse effects of poor lot conditions the feed-
lot manager may decrease the animal densities or provide a hard
surface for the lot. In either case the costs compared with dry areas
are increased and all of the other undesirable effects of climate
remain.
Earlier discussions on the amounts of runoff under varying animal
densities concluded that high densities decreased the average actual
pollution potential per animal. That is, after the runoff depth point
is passed in vertical accumulation, the average runoff per animal
decreases. Under such a situation a seemingly obvious solution for
reducing water pollution from animal wastes is to increase the concen-
trations of animals per unit of land. However, the general management
practice in humid climates would be almost directly opposite to this
solution. In other words, animal densities, because of basic manaae-
ment considerations, vary inversely with precipitation which means
decreasing densities at the time when runoff conditions would indicate
a need for increasing densities.
Lot locations and shelter provided depend upon climatic conditions
intertwined with considerations on the number of animals raised and
the animal densities. A new large-scale feeding enterprise with a
free choice of locations will tend toward the favorable climate areas.
In such cases, any shelter provided will probably be in the nature of
shade from the sun rather than protection from cold or snow. Sun
shelter usually does not affect pollution potential since it is a
minimum cost shade shelter rather than a sturdy roof with load bearing
or water shedding capabilities.
44
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In direct contrast to shade shelters in hot climates is the cold
climate shelter with protective roofing of load-bearing capabilities.
In these circumstances proper drainage of the covered areas can
significantly decrease wastes runoff from the feedlot area. In fact,
newer technology utilizing covered areas with 'slotted floors and pit
storage of the wastes- under the floors completely eliminates runoff
from the feedlot. Whether or not this new technology is adopted
depends upon several factors. Running counter to adoption ot such a
system is the high initial investment in facilities and a relatively
high investment 1n liquid-manure handling equipment. However, on the
positive side for the colder climates there is a lessening of stress
on animals, men, and equipment. Also, this system provides a positive
water pollution control solution if the liquid wastes are disposed of
properly. In the milder climates the covered system's major advan-
tages are pollution control, a simplified wastes handling method, some
decrease in land requirements, and possibly reduced nuisance problems.
Even after the feedlot location has been chosen by general climatic
region and available land, management must locate the lot at a specific
point. Climate is again a factor in that the choice location should
provide good drainage from the lot along with some shelter if needed.
Often, good drainage from the feedlot creates a water pollution
hazard of the wastes on the lot. As far as natural shelter is concern-
ed, its main effect on water pollution potential is the lessening of
any need for the types of covered operations that reduce or preclude
runoff.
The foregoing discussion indicates that water pollution resulting
from feedlot animal wastes is largely dependent upon a combination of
climatic factors and their effect on management decisions. Basically,
without precipitation there would be no runoff and, therefore, no water
pollution from feedlots. The frequency and amounts of precipitation
are, therefore, prime factors to consider when assessing potential
water pollution situations. In addition, the effects of precipitation
can be modified directly by temperature; e.g.; freezing or drying of
the wastes, or indirectly by the effects of climate on management
decisions. That is, management decisions reoarding the location of a
feedlot can change the lot's drainage pattern or, more broadly, manage-
ment can locate the lot where precipitation and therefore runoff is
minimal. Other management decisions influenced by climatic conditions
that can affect runoff are: the amount and type of shelter provided,
density of animals on the land, and the nunber of animals raised.
Since climate plays such an important role in the assessment of water
pollution potential from feedlot animal wastes, the following section
is devoted to grouping the known factors about the feedlot industry
according to geographic area and general climatic conditions.
45
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Major Feeding States
The 32 major feeding States accounted for over 23 million head of
cattle marketed from feedlots in 1968. About 20.2 million head were
marketed from feedlots in the 14 States with the largest marketings
from feedlots in 1968. (See Map 2.) It is, therefore, apparent that
the feedlot cattle operations are concentrated in relatively few States
Even more important from a water pollution standpoint is the fact
that cattle feedlots are generally more heavily concentrated in sneci-
fic sections of these States. As a result, the pollution potential,
both in total magnitude and in the cumulative effect along a water-
course, is very high for such localized areas.
Feedlot Capacities
Feedlots with capacities of 1,000 head or over accounted for
almost half of the total cattle marketed out of feedlots (Table 2.)
in 1968. However, by virtue of the capacities of these larger feed-
lots, they only account for about one percent of all feedlots. In
other words, the 2,000 lots'of 1,000 head or over capacity marketed
almost 11 million head of the slightly more than 23 million head
marketed from all feedlots in 1968. The other 206,516 feedlots of
less than 1,000 head capacity accounted for the remainder of the cattle
marketed from feedlots.
Almost 90 percent of the cattle from feedlots raising over 1,000
head come from ten States west and south of the Missouri River. (See
Table 3 and Map 3.) These ten States account for 1,522 of the
2,080 feedlots reported to have had a capacity of 1,000 head or more
in 1968. On the other hand, ten midwestern States, including an over-
lap of Kansas and Nebraska previously included in the large lot
category, account for the bulk of the small feedlots and cattle
marketed from them. From Man 4 it can be seen that these ten States
account for 185,264 lots out of the total in this under 1,000 head
size group of 206,516 and for about 10.G million out of a total of
12.2 million head marketed from this smaller group.
Many of the lots of under 1,000 head capacity are extremely small.
The average size of lots under 1,000 head in the five States with the
largest number of feedlots is only 65 head (See Table 4.) and the
average of the ten States shown on Map 4 is 57 head.
The larger feedlots with capacities of 1,000 head and over had
an average of 5,203 head marketed out of them in 1968. However, the
distribution of marketings varied considerably. For the top ten
States, ranked by total marketings in 1968, the average size of
marketing from "the over 1,000 head capacity lots ranged from 2,090
head for Iowa to 11,443 head for Colorado/ (See Table 5.)
46
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Map 2
Number of Cattle Marketed out of all Feedlots by the Fourteen States with the Largest Marketings in 1968, Location of Major
Feeding States, and Percent of Cattle Marketed from Feedlots with Capacities of 1,000 Head and Greater.
Indicates a major feeding State.
Shaded areas indicate the fourteen States with the largest cattle marketings in 1968.
Top number shown in each State refers to thousand head of cattle
Percentages shown refer to the percent of cattle marketed from feedlots with capacities of 1,000 head and greater.
Total cattle marketed out of feedlots in 1968: 14 States-- 20,219,000 head; 32 States 23,040,000 head.
-------
Table 2. Number of cattle marketed by size groups and number
of feedlots 1n each size group—1968.
Lot Size No. of Cattle Marketed No. of Feedlots
(Head)
0- 999
1000-- 1999
2000— 3999
4000-- 7999
8000—15999
16000—31999
32000- & up
Total from
all lots
Total from
lots over
1000 head
(1000 Head)
12,217
1,214
1 ,434
1,970
2,499
2,491
1,215
23,040
10,823
206,516
967
522
316
176
80
19
208,596
2,080
Source: Cattle on Feed, January 1, 1969, Statistical Reporting
Service and Crop Reporting Board, United States Department
of Agriculture, Washington, D.C.
48
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TABLE 3
Number of cattle marketed and number of feedlots by top ten States in terms of the
number of cattle marketed from feedlots with over 1000 head capacity—1968.
State
Lots over 1000 head
Lots under 1000 head
No. of lots
No. of cattle
marketed
No. of lots
No. of cattle
marketed
Total cattle marketed from all feedlots 23,040.000 head
Cattle marketed from lots over 1000 head—10,823,000 head.
Percentage of total
cattle marketed from
lots over 1000 head
California
Texas
Nebraska
Colorado
Kansas
Arizona
Iowa
Oklahoma
Idaho
New Mexico
TOTAL
288
294
463
97
100
68
165
54
81
40
1650
(1000)
2041
1858
1650
1110
803
699
345
338
338
306
9488
203
1300
21215
1263
11400
9
45835
1400
658
36
83319
(1000)
27
112
1811
321
529
4
4005
81
74
10
6974
99
94
48
78
60
99
8
81
82
97
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Map 3
Number and Percentage of Cattle Marketed from Feedlots with Capacities of 1,000 Head and Greater --Selected States, 1968
Indicates the ten States
West and South of the Missouri
River which account for almost
90 percent of all cattle marketed
from lots with capacities of 1,000
head and greater.
Top number shown in each State refers to thousand head of cattle marketed from lots
with capacities of 1,000 head and greater.
Percentages shown refer to the percent of cattle marketed from feed/ots with capacities of
1,000 head and greater.
-------
Map 4
Number of Feedlots of under 1,000 Head Capacity and Number of Cattle Marketed
From Them for Ten Selected Midwestern States, 1968.
Numbers in brackets refer to thousand
head of cattle marketed other numbers
refer to number of feedlots.
Totals for the ten States shown on map:
Cattle rnarketed--10,557,000 head
Feedlots--185,264
Average number of cattle per feedlot--57 head
-------
Table 4. Nunber of feedlots 1n selected States with under 1,000 head
capacity, number of cattle marketed from them, and their average
marketings—1968.
Name
of
State
Iowa
Illinois
Nebraska
Minnesota
Missouri
Total
Number of lots
under 1,000 head
45,835
25,963
21,215
19,865
17,968
130,846
Number of cattle
marketed from lots
under 1 ,000 head
4,005,000
1,185,000
1,811,000
818,000
644,000
8,463,000
Average
marketings
87
46
85
41
36
65
Source: Cattle on Feed, January 1, 1969, Statistical Reporting Service
and Crop Reporting Board, United States Department of
Agriculture, Washington, D.C.
52
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Table 5.— Number of feedlots in selected States with 1,000 head
capacity and over, number of cattle marketed from them,
and their average marketings--!968.
Name
of
State
California
Texas
Nebraska
Col orado
Kansas
Arl zona
Iowa
Oklahoma
Idaho
New Mexico
Total and
Average
Nunber of lots
of 1,000 head
and over
288
294
463
97
100
68
165
54
81
40
1,650
Nunber of cattle
marketed from lots
of 1,000 head and up
2,041,000
1,858,000
1,650,000
1,110,000
803,000
699,000
345,000
338,000
338,000
306,000
9,488,000
Average
marketings
7,087
6,320
3,564
11,443
8,030
10,279
2,090
6,259
4,173
7,650
5,750
Source: Cattle on Feed, January 1, 1969, Statistical Reporting
Service and Crop Reporting Board, United States Department
of Agriculture, Washington, D.C.
53
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There does not appear to be any close relationship between the
number of lots Involved and the average size of marketings front these
over 1,000 head capacity lots. Colorado, for example, had 97 lots
making up the high end of the range of averages while Iowa had 165 lots
making up the low end of the averages. Out of this ten State group
California, Texas, and Nebraska had the largest nunber of lots over
1,000 head while New Mexico, Oklahoma, and Arizona had the fewest.
The distribution by size of feedlots within the 1,000 head and
greater capacity lots provides an indication of the control problems
by lot size and regional location. In general, as lot sizes increase
there is a progressively greater wastes handling problem. With
Increasing lot sizes there are increasing quantities of wastes to be
handled, more wastes to be stored prior to disposal, and the ratio of
nearby land available for waste disposal to the quantity of wastes
decreases. This means that day-to-day wastes handling problems of
large lots are similar to those of small lots and yet different enough
to require different solutions. Use of nearby land, for example, can
minimize storage requirements, reduce quantities of wastes subject to
runoff, and provide for disposal of runoff caught in detention ponds.
However, use of nearby land for disposal from very large feeding
operations can create additional potential water pollution situations
because of the size of the disposal problem.
Increasing quantities of wastes to be disposed can mean increasing
travel distances to the last added disposal site, increasing quantities
of wastes per disposal site, or some combination of both. From a
disposal cost standpoint the least-cost method is to add greater
quantities of wastes to the nearby sites, at least up to some point
prior to decreasing crop returns. However, increased quantities of
wastes disposed per unit of land increase the likelihood of water
pollution from the disposal areas and may even increase the total
water pollution problem rather than decrease it.
As would be expected, the number of feedlots 1n each size category
declines very rapidly as the lot capacities increase beyond 1,000 head.
(See Table 6.) However, the trends do Indicate that all feedlot
sizes will be Increasing and that there will be continued growth 1n the
number of large-scale lots. The 32-State total in Table 6 shows
that the bulk of the 1,000 head capacity lots fall within the 1,000 to
3,999 head capacity range. In fact, if the range Is expanded to
Include up to 7,999 head capacity lots, this new range Includes 1,805
of the 2,080 lots with capacities of 1,000 head and greater.
54
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Table 6.—Number of cattle feed lots In various specified size
groups 1n selected States—I968.
Name
of
State I/
California
Texas
Colorado
Kansas
Nebraska
Arizona
New Mexico
Oklahoma
Idaho
Iowa
Ten-State tot.
32-State
total
1,000 to
1,999
75
121
21
24
270
13
8
24
35
113
704
967
Feedlot
2,000 to
3,999
Number of
85
68
30
28
113
15
14
17
19
_35
424
522
capacity
4,000
7,999
feed lots
55
52
20
23
57
21
6
4
19
13
270
316
size ranges
to 8,000 to
15,000
1n each range
45
30
16
17
15
10
8
6
5
_A
156
176
16,000
and up
28
23Z/
10 y
8
8l/
92/
4
3
3
_g
96
99
Source: Cattle on Feed, January 1, 1969, Statistical Reporting
Service and Crop Reporting Board, United States Department of
Agriculture, Washington, D.C.
J/ The numbers shown by States under any specified size group
may have been conblned In the source table to avoid Identify-
ing Individual operations.
2/ Lots from larger size groups have been Included In this
group in the source table to avoid disclosing Individual
operations.
55
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From the foregoing discussion 1t 1s evident that there are some
definite points to be considered when assessing the need for and
applicability of pollution control measures for various sized feedlots.
Additional breakdowns of the large-scale feedict figures In Table 6
show that 96 out of a total of 99 feedlots with capacities of 16,000
head and over are accounted for by nine of the ten top States 1n
cattle marketings from lots over 1,000 head capacity. Also, 1t shows
that these ten States account for 252 of the 275 lots with capacities
of 8,000 head and greater.
A comparison of Tables 6 and 7 provides an Indication of the
trend toward larger feedlots. In 1962, there were only 1,517 lots with
capacities of over 999 head compared to 2,080 such lots 1n 1968. The
absolute Increase declined by size range as the size ranges Increased.
That 1s, Increases 1n feedlot numbers from 1962 to 1968 ranged downward
from 166 additional lots 1n the 1,000 to 1,999 head capacity group to
68 lots 1n the 16,000 head and over group. However, the percentage
changes In feedlot numbers followed an exactly opposite trend. In
relative terms, therefore,. the larger lots showed larger Increases
from 1962 to 1968. That 1s, the Increases ranged upward from 21
percent for the 1,000 to 1,999 head capacity group to 219 percent for
the 16,000 head and up group.
From Nap 3 and Table 6 1t can be seen that most of the large
feedlots are located south and west of the Missouri River. Although
specific feedlot locations and corresponding cllmatologlcal data are
not presently available, 1t 1s known that the climate 1s less severe
1n most of these States than in the States where the majority of the
small lots are located. In fact, In several of the States with the
majority of the large lots, the climate can be considered as dry.
Another perplexing problem, In terms of evaluating the current
pollution problem and forecasting future changes, 1s how to differen-
tiate size groups 1n the 206,516 lots of under 1,000 head capacity.
In this size group the average number of cattle marketed 1n 1968 was
59 head. Even 1f the lots are restricted to those found in the ten
mldwestem States with somewhat similar climatic conditions, the
magnitude of the problem remains large. That 1s, in these ten mid-
western States there were 185,264 lots of under 1,000 head capacity.
About 10.6 million head of cattle were marketed out of these lots 1n
1968 for an average marketing of 57 head. (See Map 4 .)
Feedlot operations are not continuous year-around operations for
the vast majority of feeding enterprises. That 1s, the lots are not
used for cattle feeding during some substantial portion of the year.
Although there 1s a great deal of variation among feeding enterprises
1n the length of time cattle are kept on feed and in the number of
feeding cycles completed annually, a common feeding program handles
only one feeding cycle annually and the cycle usually lasts from 90
to 120 days.
56
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Table 7.--Number of cattle feedlots 1n various specified size
groups In selected States—1962.
Name
of
State I/
California
Texas
Colorado
Kansas
Nebraska
Arizona
New Mexico
Oklahoma
Idaho
Iowa
Ten State
Total
32-State
Total
1,000 to
1,999
106
98
31
24
202
30
10
13
37
33
584
801
Feedlot
2,000 to
3,999
Number of
100
60
19
8
75
25
12
10
12
3 2J
324
385
capacity size ranges
4,000 to
7,999
feed lots 1n
41
31
16
12
24
21
7
62/
11 2/
0
169
194
8,000 to
15,000
each range
37
14 2/
14 2/
9 2/
11 2/
11
5
0
0
0
101
106
16,000
and up
16
0
0
0
0
7
0
0
0
0
23
31
Source: Cattle on Feed, January 1, 1969, Statistical Reporting
Service and Crop Reporting Board, United States Department
of Agriculture, Washington, D.C.
iy The numbers shown by States under any specified size
group may have been combined In the source table to
avoid disclosing Individual operations.
2/ Lots from larger size groups have been Included In
this group In the source table to avoid disclosing
Individual operations.
57
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In the Midwest, cattle feeding operations are generally only one
portion of the overall farm enterprise. By feeding cattle during the
late fall through early spring period, feeding operations can take
advantage of off-season labor availability and home produced feeds.
On the other hand, as feeding enterprises Increase 1n size, with the
resultant larger capital Investments 1n fixed facilities and the
necessity for additional labor, the feeding operations tend to become
year-around with a constant turnover of animals through the lots.
Since feeding operations are Intermittent, the number of lots 1n
operation at any single point in time 1s less than the total number
of lots operating during some part of the year. Table 8 shows the
estimated numbers of feedlots and cattle and calves on feed on
April 1, 1966 by various size categories.
The estimated feedlot and cattle numbers In Table 8 are the most
recent estimates available on such a broad geographical base. Although
since then changes have undoubtedly occurred in total numbers as well
as 1n numbers within size groups, any changes that occurred 1n such
broad ranges and on a national scale would not effect the points made
here.
Most of the feedlots 1n operation on April 1, 1966 (Table 8) had
capacities of less than 151 head and accounted for over one-third of
the total cattle on feed at that time. Thus, It can readily be seen
that any determination of feedlot pollution problems and costs of
pollution control must ultimately either Include or exclude these
relatively small lots from specific consideration. If these lots can
generally be excluded because they are not a source of water pollution,
the total cost estimates of pollution control will be reduced. Con-
versely, 1f these lots are shown to be sources of water pollution,
applicable control measures must be developed and their costs Included
1n the total cost estimates.
The concept of feedlot location by climatic region discussed
previously showed how the feedlots marketing cattle 1n 1968 were
distributed by State. In general, this discussion concluded that the
smaller lots were located 1n the States with colder and more humid
climates while the very large lots tended to be found In the States
with warmer and less humid climates.
If the geographical regions shown 1n Map 5 are used as a base
for describing feedlot locations on April 1, 1966, the sharp demarca-
tion of average lot sizes among regions can be seen (Table 9). Of
course, there 1s some masking effect, because of the use of averages,
on the growing number of large-scale feedlots 1n each area, especially
In the Northern Plains region. In fact, the earlier discussion
pointed out that Kansas and Nebraska actually fell Into a dual
category being major locations of both large and small feedlots.
58
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Table 8.— Total operating feedlots and total cattle and calves on
feed by specified feedlot size groups, April 1, 1966.
Feedlot size group
Feedlots with
cattle and
calves on feed
Total cattle
and calves
on feed
Average
per
Feedlot
32-State total
Number
109,438
Head
10,227,000
Head
1 to 50
51 to 150
151 to 300
301 to 500
501 to 1,000
1,001 to 5,000
5,001 and up
73,704
23,131
8,930
1,927
1,032
548
166
1,692,000
2,146,000
1,919,000
770,000
709,000
1,149,000
1,842,000
23
93
215
400
687
2,097
11,096
93
Source: Urea Consumed by Cattle on Feed, Feeding Year 1965-66,
Agricultural Economic Report No. 158, Economic Research
Service, United States Department of Agriculture,
Washington, D.C.
59
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Map 5
Description of Geographic Regions
NORTHERN
PLAINS
60
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Table 9.— Total operating feedlots and total cattle and calves on
feed by specified region, April 1, 1966.
Production Region
Northeast
Lake States
Com Belt
Northern Plains
Appalachian
Southeast
Delta States
Southern Plains
Mountain
Pacific
32-State total
Feedlots with
cattle and
calves on feed
Number
2,005
18,154
59,196
24,086
669
623
160
1,082
2,613
850
109,438
Total cattle
and calves
on feed
Head
77,000
815,000
3,918,000
2,114,000
91 ,000
142,000
12,000
662,000
1,359,000
1,037,000
10,227,000
Average
per
Feedlot
Head
38
45
66
88
136
228
75
612
520
1,220
93
Source: Urea Consumed by Cattle on Feed, Feeding Year 1965-66,
Agricultural Economic Report No. 153, Economic Research
Service, United States Department of Agriculture,
Washington, D.C.
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Common Control Methods
Beef feedlots are known sources of water pollution but the extent
and distribution of pollution caused by such feedlots Is unknown.
Further, the present state of knowledge does not permit an adequate
estimation of the numbers or types of control facilities that are need-
ed to control water pollution from feedlots. However, an Indication
of the size and variability of the control problem may be obtained
through a general discussion of the known control methods and their
applicability under varying conditions.
Types of pollution control measures utilized by feedlot enter-
prises will vary significantly across the nation as well as within a
specific local area. There 1s no one best solution for controlling
pollution from feedlots although there are solutions that have general
applicability to feedlots 1n similar situations. In fact, It 1s this
general applicability 1n similar situations which will allow future
estimations to be made as to the total costs of controlling pollution
from animal feedlots.
Control measures range widely in complexity and cost. Minimal
control measures, 1n terms of cost and complexity, are water diversion
systems that divert drainage water around the feedlots, changes 1n the
drainage route of runoff from feedlots, and, possibly, changes 1n lot
locations to minimize drainage water moving across the lot or to prevent
direct drainage from the lot to a watercourse. Other changes in
operations such as Increasing animal concentrations through decreasing
lot sizes or adjusting feeding cycles to meet changing climatic condi-
tions can, in some cases, also be used to reduce or eliminate water
pollution from feedlots with minimum expenditures.
More costly control measures, at least in terms of capital Invest-
ments and operating costs, would Include systems with completely
covered feeding operations and full treatment of the wastes. Of course,
between the minimal control situation and the maximum control situation
there are numerous other control measures and combinations of these
measures that can be used.
For the vast majority of feedlots the determination or estimation
of total wastes washing from the lot 1s probably Irrelevant. The
critical factor that must be determined Is whether or not runoff from
the lot ever results 1n water pollution. If the lot 1s a source of
water pollution, whether regular, Intermittent, or seldom, 1t 1s
reasonable to assume that the pollution must ultimately be controlled.
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The type of control measure adopted by any lot contributing to
water pollution does not depend upon the amount of wastes washed from
the lot. Rather* the control measure adopted depends upon a variety
of factors chief among which are the amounts of water that must be
contained or diverted, the possibility of cost savings, and the ability
of the system to offset Inadequate labor supplies. Intertwined with
these chief factors 1n determining the type of control measure to be
adopted are such things as lot size, climate, and type of feeding
operation.
For purposes of describing some common control measures and their
applicability to similar feedlot situations, feedlots may be categor-
ized as small, medium, large, and extra large. Realizing that there 1s
no single point, or even series of points, at which feedlot sizes can
be divided to provide all-Inclusive descriptive feedlot categories,
the following numerical definitions may be used to describe small,
medium, large, and extra large feedlot categories. Small lots range
from zero through 150 head capacities, medium lots from 151 through
1,000 head capacities, large lots from 1,001 to 15,999 head capacities,
and extra large lots range upward from 16,000 head.
Small lots are found across the country but are most prevalent
1n the mldwestem region. If these lots are sources of water pollu-
tion, the easiest and most likely control measure to be Implemented 1s
a combination of water diversion around the lot and changes 1n lot
size to obtain proper animal concentrations for runoff minimization.
In some cases relocation of the lot may be needed to accomplish the
necessary control but there 1s usually strong resistance, for a
variety of reasons, to lot relocation.
Lagoonlng or detention of the wastes as well as covering of the
feeding operations can be used to provide the needed pollution control
although 1t 1s doubtful that such measures will find extensive use 1n
small operations. Climate has little effect on the type of control
measure applicable to small lots since the same measures are both
effective and least-cost 1n humid as well as dry areas. However,
there 1s less likelihood of water pollution occurring from a small
lot located 1n a dry area.
Medium and small sized lots often have similar water pollution
problems and solutions. Therefore, medium sized lots cannot always
be categorically separated from small lots. However, there are large
numbers of lots In the medium category that require more extensive
control measures than the small lots require.
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Medium lots 1n dry areas may be able to control pollution through
use of water diversion methods and sizing of lots to optimize animal
concentrations or, 1n some cases, through a combination of both methods
along with a detention pond. Humid areas and areas with cold climates
may make use of various combinations of control methods sirh as water
diversion and detention, covered feeding operations, lots sized to
optimum animal concentrations, and lagoonlng of the wastes. Although
water recycling 1s generally considered as being best suited to dairy,
hog, or poultry operations with water flushing systems, it is possible
that further refinement or research may prove the system feasible for
medium to large feedlots.
Large lots, which fall between the medium and extra large cate-
gories, need not be specifically discussed. The control measures
utilized by this group will closely parallel those utilized by the
adjoining groups, depending upon such Items as climate, management
requirements, present facilities, and lot location.
Extra large lots are generally found in the drier and milder
climates. Therefore, solutions such as water diversion, lot sizing
for optimum animal concentration, and supplementary detention ponds
are likely to be used in extra large lot situations. In some cases
complete elimination of runoff results when slotted floors and pit
storage of the wastes under the animals are used as part of the
wastes handling and nuisance control program.
In cases where extra large feedlots are located in harsh or humid
climates, covered feeding operations with slotted floors and pit
storage of wastes under the animals is a possible means of controlling
water pollution. Such a system is, of course, a positive method of
runoff control but the investment costs 1n buildings, floors, and pits
are quite high. Therefore, the attractiveness of such a system to
feedlot operators lies mainly 1n the cost reductions that accompany
Installation of the system. Savings resulting from Installation of
the system might come from items such as decreased land, plumbing,
surfacing, and fencing requirements, lower disease and death loss
rates, higher degrees of nuisance control, lower labor requirements,
decreased equipment maintenance costs, and ease of management control.
The preceding discussion of feedlots by size categories generally
touches upon common water pollution control measures that night be
employed by lots in similar circumstances in the various size cate-
gories. This discussion 1s not meant to be completely comprehensive
nor Is 1t meant to Imply that these measures are acceptable in all
cases. Rather, the discussion 1s presented to show that there are
common factors which can be utilized In developing estimates of the
cost of controlling water pollution from feedlot operations.
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Other systems which Incorporate almost complete elimination of
wastes may find extensive use in the future because of their labor
saving qualities. For example, Incineration of wastes on a dally basis
or some form of treatment process that reduces or minimizes waste
handling might be practical under certain conditions. Although the
costs* Including loss of value of the wastes PS fertilizers, feeds,
soil conditioners, etc., make the wastes elimination systems unfeasible
under present conditions, such systems should be considered over time
1n the event that changes In cost relationships or in feedlot opera-
tions make the systems feasible for adoption by the Industry on a
broad scale.
Description of Selected Control Methods
This section briefly describes some of the control methods present-
ly 1n use by the cattle feeding Industry that appear to have potential
for widespread adoption as discussed in the previous section. These
control methods, depending upon the particular circumstance, may be
used alone or in combination with one another. Water diversion, for
example, may be used in conjunction with most of the other methods to
enhance their effectiveness or decrease their costs.
It Is concluded that although these methods have potential for
widespread adoption, additional study and analysis Is required before
they can be used as a basis for estimating total feedlot pollution
control costs. The costs and savings resulting from adoption of each
control method should be determined along with the applicability of
each type of control measure to various feedlot situations. Also, the
growth of the feeding Industry needs to be predicted by location, lot
size, and animal numbers. This growth prediction should take Into
account development of new technology and the effects of overall
environmental pollution control requirements on the Industry. Water
or air pollution abatement costs, for example, could change the
comparative advantage relationships among regions that now exist.
Covered feeding operations can provide a means of water pollution
abatement for all sizes of feedlots In harsh and humid climates.
However, they may find their most extensive use in the medium to large
size categories when pit storage of the wastes with a liquid wastes
handling system have been Incorporated in the building setup.
Partially covered feeding operations are found 1n many small feed-
Ing enterprises because bams and other buildings are available for
conversion to shelter uses. Partially covered lots can contribute to
water pollution control but the effect 1s highly variable, depending
upon the extent of covering and season of the year. Very limited cover
relative to feedlot size and number of animals does not provide much
runoff control during most seasons. However, during very cold weather
the shelter may be used extensively by the animals which keeps the
wastes generally confined to the covered area. However, disposal of
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the wastes may create a water pollution hazard unless proper safeguards
are followed. In cold climates, over-winter storage of the wastes 1n
controlled runoff areas may be required. In all climates adequate
storage areas for wastes accumulated during wet periods may be neces-
sary. In any case, the costs of these additional safeguards must be
considered along with the shelter costs when estimating total costs.
Fully covered operations are most practical when slotted floors
and pit storage for the wastes are provided. Although addition of
these two Items significantly raises the capital costs, they do allow
the system to take full advantage of labor savings, wastes quality
control, and savings 1n land, fencing, buildings, lot surfacing, and
associated costs. There are, however, some additional problems associ-
ated with a liquid wastes handling system that must be considered 1n
analyzing the feasibility of a covered feeding operation with a
liquid wastes handling system.
Diversion
Routing water away from feedlot surface or away from a watercourse,
where applicable, 1s probably the easiest and least-cost method of
controlling water pollution from feedlots. In Its simplest form diver-
sion can be accomplished by diking or channelling on the high end of
the feedlot and along the sides so that water from other surface areas
1s channelled around the lot. Such diking or channelling can generally
be accomplished with operator labor and equipment. However, the opera-
tor may require outside consultation to determine the necessary size
for the dikes or channels to accommodate climatic and hydrological
aspects of the area. He will also need to provide the proper slope
and use adequate materials to prevent erosion or gullying when the
dikes or channels are Installed.
The optimum concentration of animals 1n the lot can be used alone
or 1n combination with other measures to prevent water pollution from
runoff or to minimize costs of other pollution control measures. When
used In conjunction with diversion measures, for example, optimum
animal concentrations can reduce the needed footage of diversion
channels or dikes; that 1s, optimum animal concentrations can mean
that the same number of animals are fed in a smaller land area.
Therefore, the three sides requiring diversion measures are smaller
for the same number of animals.
Changes in lot location can also be a method of water pollution
control or a cost minimization technique when used 1n combination with
other control Measures. Locating the lot well away from watercourses
or drainage channels can prevent water pollution stemming from the
feedlot surface. In other cases the lot may be relocated to minimize
the encroachment of surface water from other land areas around the
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feedlot. Reduction In outside runoff water reduces the need for, or
size of, other control measures such as diversion structures, or
detention ponds and lagoons. The cost of lot relocation depends upon
several factors such as other uses that can be made of the present
lot, Its facilities, convenience of the new location for labor and
herd management, fencing, surfacing, building, ant! associated costs
necessary to make the new location usable.
Detention
Runoff water detention 1s another method for complete control of
water pollution from the feedlot if the detention ponds are sized
properly to handle maximum rainfalls and accumulations during extend-
ed rainfall periods when the ponds cannot be emptied. The following
description of a feedlot utilizing a runoff detention system explains
how the system operates and details some of the system's limitations.
In broad terms a runoff detention system must Incorporate water
channelization measures 1n the feedlot layout, have an adequate holding
pond or area, and have an acceptable method of removing some or all of
the runoff from the detention pond between rainfalls. It can also be
assumed that, where feasible, runoff minimization techniques such as
proper lot location, optimum animal concentrations, and water diversion
measures will be adopted 1n conjunction with the detention system.
Such techniques decrease the necessary detention pond size and lower
the volume of runoff to be disposed of, both of which reduce the costs
of a detention system.
Channelization requirements are basically the same irrespective of
the type of detention pond evacuation system employed. In order to
effectively use a detention system the feedlot must be sloped or
drained so as to channel all the runoff water Into the detention pond.
In addition, the shaping should probably minimize the amount of solids
transported from the lot into the detention pond.
The size or capacity of the detention pond Is dependent upon the
climate, lot size, and type of evacuation system employed. For
purposes of Illustration here the evacuation systems are limited to
either an evaporation system or a mechanical system using a pumping
operation combined with irrigation disposal.
Evaporation systems, because of the water surface area required
for evaporation, are only practical 1n areas where the evaporation
rate 1s relatively high compared to the precipitation rate. Also,
such a system presupposes that odors associated with the pond will be
within an acceptable range.
The primary advantages of an evaporation system are minimal opera-
tion costs and limited management requirements. If the evaporation
pond has been adequately designed, natural evaporative processes remove
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the runoff water from the pond. Therefore, there is no operating
cost nor any need for management of the runoff removal associated with
an evaporation system as opposed to a mechanical pump-out system.
However, there 1s the cost of periodic cleaning of the evaporation pond
which may or may not be required as frequently as cleaning of ponds
using mechanical evacuation. Also, there Is a management factor
Involved in the cleanout. That is, the evaporation ponds must be
cleaned before the accumulating solids transported into the pond by
runoff water build up to a point where the remaining pond capacity is
inadequate to detain all the runoff.
Major disadvantages of an evaporation system, even in a suitable
climate, are the land requirements and complete dependence upon
natural processes to remove collected runoff water. Land requirements
for the evaporation pond are directly related to runoff volume and
Inversely related to the evaporation rate. That is, the surface area
of the water that must be exposed to the air for evaporative purposes
decreases as the rate of evaporation increases but as total runoff
increases the pond size must Increase.
For any given area, once the evaporation rate has been determined,
the ratio of required surface area to runoff volume will probably
remain constant. Therefore, for each Increase in runoff volume a
proportionate Increase in surface area is necessary. In contrast, a
mechanical system can accommodate larger runoff volumes by increasing
pond capacities through Increases 1n pond depths rather than in surface
area. Also, in contrast to the mechanical system, the evaporation pond
must be substantially larger to allow for the slower rate of runoff
water removal. Additionally, because of the large surface area
required and the total amount of runoff that must be retained, the
evaporative system adds to its own size requirements by providing a
larger surface area for rainfall collection.
Complete dependence upon natural processes must either more than
proportionately add to the design size of the system when compared to
a mechanical evacuation method or decrease the reliability of the
evaporation method. In other words, an additional variable, I.e.,
evaporation rate, must be taken Into account when designing the eva-
porative system. Changes in the evaporation rate because of such
factors as cloud cover or humidity changes do not affect the mechanical
system but are Important to the evaporative system.
Modified versions of the detention pond may also be used where
evaporative systems are feasible. One modified version would Involve
r1doing and furrowing the lot surface to detain the runoff on the lot
proper rather than in a special pond. Such a method would be subject
to the same climatic limitations as the evaporation pond but there
is a possibility of land savings with on-the-lot detention and evapora-
tion. However, there is no information presently available as to the
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additional land requirements, 1f any, to provide adequate space for
the cattle and at the same time allow space for detention and evapora-
tion of occasional rainfalls.
Mechanical evacuation 1s accomplished by means of a pump removing
water from the detention pond and forcing 1t through piping to a dis-
posal area. The disposal area may be one of three general types:
productive land, non-productive land, or land removed from production.
The runoff water and wastes may be pumped from the pond and
sprayed onto productive crop or pasture areas in concentrations and
quantities that add to the fertility of the soil but do not exceed the
crop's requirements, Impair crop growth, or adversely affect soil
structure. Using a crop or pasture disposal area provides a fertilizer
value offset to the waste disposal costs, does not remove land from
remunerative production, and makes use of land that may be more readily
available than non-productive land sites. Chief disadvantage of such
a disposal area 1s the large land requirement which results in greater
costs for piping and pumping, especially as the feedlot sizes become
very large. Also, the pond evacuation must often be undertaken
during wet periods when soil moisture Is already high. However, with
a large enough disposal area, this wet weather evacuation could most
likely be accomplished without detrimental effects to either crops
or water quality.
Non-productive land can be used as an evaporation area for the
disposal of runoff water from the detention ponds. Owens and Griffen ±/
considered the use of pi ay a lakes in the Texas High Plains area as
possible disposal sites for runoff water pimped from detention ponds.
It was concluded that use of a playa lake was a low cost disposal
method since no land had to be taken out of production to provide the
disposal site. Other non-productive land could similarly be used but
It would also have to meet certain requirements. First, there should
be no problem with surface runoff from the disposal area. Second,
the soils and groundwaters should be studied to assure that no pollu-
tion occurs through percolation of the wastes through the soil into
groundwater. Third, odors, nuisances, and similar problems associated
with the disposal site should be within acceptable limits. Fourth, if
the water at the disposal site 1s to be used for other purposes such
as Irrigation or livestock watering, the nutrient, mineral, and salt
concentrations must be carefully monitored to prevent any undesirable
side effects from the presence of the runoff water.
2/ Economics of Water Pollution Control for Cattle Feedlot Operations.
Owens, T.R. and Griffen, Wade L., September 1968; Department of
Agricultural Economics, Texas Technological College, Lubbock, Texas.
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It 1s possible that land could be removed from production and
used primarily as a disposal site for runoff pumped from the detention
pond. Under such a system the disposal site might be used for growing
some type of salt-tolerant crop but the crop itself would have to be
of secondary Importance. Studies reported by Wells et. al. J/, for
example, Indicate that high rates of runoff water application are
detrimental to several types of crops but that Midland Bermuda grass
has a high tolerance for such runoff.
Primary disadvantages of this land removal system are the high
cost of the land removed from production and the lack of Information
regarding movements of nutrients, salts, and minerals through various
soil types under heavy runoff application rates. Additional questions
also remain as to the long-term effect of the high disposal rates on
soil structure. If the soils eventually puddle and lose their absorp-
tion capacity, then the disposal area will become an evaporation area
subject to the same restrictions as cited previously for non-productive
land.
The size of detention pond necessary with a mechanical evacuation
system depends upon the size of the feedlot, maximum and cumulative
rainfalls, and the size of the evacuation system. Unlike the evapora-
tion system, the land requirements for a pond with a mechanical system
can be minimized by Increasing the pond's depth. Of course, there are
practical limits to pond depth and they will vary from area to area.
Design analysis of Individual feedlot enterprises of regional varia-
tions can be used to determine the least-cost combination of pond size,
depth, and pumping capacity. In some cases land costs or availability
may be such that extra costs for Increasing pond depths are justified.
On the other hand, ample or cheap land may justify the use of larger
and shallower ponds with consequent lower pumping capacity needs and
decreased pond construction costs.
Even 1n cases where runoff detention Is feasible, 1t only provides
a solution to one part of the enterprise's wastes management problem.
Each animal dally deposits the equivalent of about ten pounds of dry
waste material on the feedlot surface. Although some of the wastes
may be washed from the lot Into a detention pond by rainfalls, the
major portion of the wastes must be mechanically removed from the lot
3/ "Characteristics of Wastes from High Plains Cattle Feedlots,"
Wells, Dan M., Grub, Walter, Albln, R.C., Meenaghan, George P., and
Coleman, Eugene, Paper presented at ASCE, Fall Meeting, Texas Section,
Lubbock, Texas, October 1969.
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at varying time Intervals. These wastes may be Immediately disposed
of 1n conjunction with the cleaning process but, for the larger lots,
the wastes are most likely stacked to await disposal at a more oppor-
tune time. Safeguards must, therefore, be Instituted to assure that
runoff from the stacks 1s contained or channelled Into a detention
pond and that field disposal does not subsequently result 1n water
pollution.
Covered Operations
Covered feeding operations with pit collection and storage of the
wastes under the animals, although still relatively rare operations,
are apparently gaining in popularity 1n the colder climates. Use of
such covered feeding systems can be one solution to water pollution
problems from fat cattle wastes 1f care 1s taken when the wastes are
disposed of on land areas.
A typical fully covered feeding operation with under-animal
storage 1s designed so as to keep all of the animals under cover at
all times during the feeding cycle. In order to accomplish this with
current technology, the simplest method 1s to provide a three-sided
pole barn with metal sides and roof, a cement pit under the roof, and
a slatted floor covering over the pit. Although one full lengthwise
side of the building remains open to provide adequate ventilation 1n
both winter and summer, almost all precipitation 1s kept away from the
animals and their wastes.
Slatted floors are used in conjunction with pit storage to allow
the wastes to fall Into the pit and thereby avoid any wastes build-up
between cleanings. The size and spacing of slats may vary but a
common size Is five Inches 1n width with spacings of one and one-half
Inches between the slats. In some cases the slat 1s slightly raised
In the center to facilitate automatic cleaning. Action of the cattle's
hooves and their body heat tends to prevent a manure build-up on the
slats 1n all but the coldest weather If proper animal concentrations
are maintained.
Since wastes are automatically moved downward through the slatted
floors, pits must be provided for accumulation of the wastes. The size
of pit Is dependent upon the frequency of cleaning but 1n cold climates
it appears desirable to have adequate storage for at least three months
and probably longer. Added storage allows more flexibility In the
cleaning operations and 1s particularly Important when weather condi-
tions do not permit spreading of the wastes.
Wastes accumulated in the pit are in a slurry form and can be
handled as a liquid. As a rule, when cleaning operations are begun, a
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rotary pump Is placed in the pit in the reverse operating position so
that the wastes are circulated and thoroughly mixed. The pump 1s then
operated in the forward position and the wastes pumped Into a specially
built tankwagon for removal to the disposal area.
Although it 1s possible for any size feeding enterprise to utilize
a liquid wastes handling system, costs of pumping and hauling equip-
ment reduce the economic feasibility of such systems for smaller
enterprises. Pits, floors, and buildings can be scaled to any desired
capacity but pumping and hauling equipment cannot be purchased in
sizes smaller than the manufacturer's minimum size. Therefore, the
fixed cost of the oversized equipment 1s spread over only a few animal
units 1n the smaller enterprises which results in a high average unit
cost for the system.
Even for enterprises sized to take advantage of economies of size
associated with wastes handling equipment and facility construction,
the costs of providing full cover and a liquid wastes handling system
are significantly greater than costs of a standard open lot. There-
fore, the covered system must have offsetting operating advantages or
economies to make It practical for adoption. Wastes accumulated in
pit storage, for example, maintain their fertilizer value and can be
readily analyzed for nutrient content. Analyses have shown that a
ton of beef cattle wastes contain about 6.5 pounds of nitrogen, 4.5
pounds of phosphate and seven pounds of potash. Also, there is no
bedding cost with a covered system and labor costs are reduced while
herd care and management 1s enhanced.
Another prime savings attributable to a covered system is in land
needs. With a covered system each animal requires slightly more than
20 square feet of lot or floor space. When compared to the 100 to 150
square feet needed on hard surfaced open lots and the over 200 square
feet required for dirt surfaced lots, it is evident that land and
associated confinement costs such as fencing are substantially lower
for the covered system. There 1s also evidence Indicating that feed-
Ing efficiency 1s Improved during the winter when animals are provided
with simple shelter similar to that of a covered feeding system.
Disease problems and death losses can also be reduced with the covered
system because of lowered stress on the animals and Increased herd
management. A final saving on men and equipment 1s possible when
part of the covering 1s over driveways and feeding lines so that equip-
ment can be moved freely during the most adverse weather conditions.
More detailed studies in the future will determine the actual
costs and savings attributable to the aforementioned factors that are
part of a covered feeding system. Once the costs and savings have
been determined by enterprise size and location, the applicability of
this system as a water pollution control measure can be predicted and
used In estimating total water pollution control costs. The inter-
action of all pollution control requirements (e.g., air and water
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pollution and nuisance control regulations) and changes in feeding
technology and equipment must be factored Into the prediction of
regional cattle feeding locations. These factors can change the costs
of feedlot operations and are particularly important In analyzing the
future of covered feeding systems. Added costs in the mild climates
may reduce or eliminate the comparative advantage now found in these
milder climates.
Such a change In comparative advantage could result in future
shifts In the production locations in favor of the harsher and more
humid climates. Shifts in production areas would, in turn, bear on
the estimated costs of animal wastes pollution abatement.
The selected control methods summarized here are just a few of
the many control measures that might be used In animal wastes pollution
abatement. Although these measures appear to be relatively low in net
cost and widely applicable, there are other more costly measures that
may be required in special circumstances. The general control
measures discussed do, however, serve to Indicate avenues of analysis
and courses of future study for use in developing estimates of the
total cost of controlling water pollution from feedlots.
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DAIRY CATTLE
The number of milk cows on farms has steadily declined over the
past couple of decades (See Table 10). This decline extends from a
peak of 25.6 million head in 1944 to 12.7 million head In June 1969.
Despite this decline, however, the number of cows remaining, combined
with the changed technology, I.e., greater use of cleaning water, more
Intensive confinement, Increased production per animal, and more
animals per enterprise, make further Investigation Into the water pol-
lution potential of dairy farms necessary.
TABLE 10
Number of H1lk Cows on Farms, 1944-1969 ]J
Million Head
1944—25.6 1953—21.7 1962—17.1
1945—25.0 1954—21.6 1963—16.5
1946—24.1 1955—21.0 1964—16.1
1947—23.3 1956—20.5 1965—15.0
1948—22.3 1957—19.8 1966—14.1
1949—22.0 1958—18.7 1967—13.5
1950—21.9 1959—17.9 1968—13.0
1951—21.5 1960—17.6 1969—12.7
1952—21.3 1961—17.4
!_/ 1944-1964: Average number on farms during year, excluding nelfers
not yet fresh.
1965-1969: Number on farms on June 1 of each year.
Sources: "Statistical Bulletin No. 303" and Supplements* Economic
Research Service, United States Department of Agriculture,
Washington, D. C.
M1U Production, August 12, 1969, Statistical Reporting
Service and crop Reporting Board, United States Department
of Agriculture, Washington, D. C.
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Dairy farm operations may fall Into any one of the four discharger
categories used in this report. However, trends toward larger herds
and Increased need for labor efficiency tend to shift the operations
within the discharger categories so that a greater proportion of the
operations fall Into the higher discharge frequency categories. For
example, hydraulic flushing reduces labor requirements for the cleaning
operations but almost Invariably the operation then discharges wastes
regularly. The same type of shift occurs when small operations with
little or no water pollution potential go out of business but their
animals are purchased by other dairy enterprises that have a greater
water pollution potential. Thus, the trend to fewer and larger dairy
farms does not necessarily mean that water pollution will decrease.
However, it does mean that the enterprises will be easier to locate
and aid in pollution control since they will be fewer and have more
common problems and solutions.
Location of Milk Cows
Milk cows are generally found throughout the United States (Map 6).
In the case of fluid milk, the production areas are often related to
population centers while in the case of the less perishable manufactured
dairy products processing plants are often located in areas where milk
production has a comparative advantage. The upper Midwest and North-
eastern areas lead in the number of cows on farms. Of the States with
over 500 thousand head of cows on farms on June 1, 1969, Minnesota,
Wisconsin, and Iowa, all in the Midwest, had a combined total of 3.4
million head, New York and Pennsylvania in the Northeastern area had
a total of 1.75 million head, and California in the West had 0.8
million head.
The cow numbers shown here only serve to Indicate major concentra-
tions of cows which, in turn, can serve as an Indicator of areas where
significant potential water pollution may exist. The actual pollution
resulting from individual enterprises 1s, however, highly dependent
upon the manure handling and disposal systems used by the enterprise,
the climate, and the proximity of the enterprise or Its disposal area
to a watercourse.
Common Control Methods
A few of the water pollution control practices now in use In-
clude lagoons, covered operations with mechanical cleaning and disposal,
some liquid manure handling systems, runoff diversion, and flush water
containment with Irrigation disposal. These measures vary as to appli-
cability, cost, and effectiveness at the present time. However, ongoing
research In the areas of biological treatment of animal wastes, land
disposal problems and criteria, water recycling, and production tech-
nology should provide the basis for assessing the effectiveness of
these and other control methods and the applicability of the methods
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Map 6
Number of Milk Cows on Farms, by States, June 1969.
Alaska- 1.8
Hawaii- 12.6
Numbers in each State represent thousand head of cows
Shaded areas indicate States with over 500 thousand head.
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under varying conditions. The knowledge of unit costs and appli-
cability of control measures under various circumstances can then be
combined with Information on size and location of dairy farms to arrive
at an estimate of the cost of controlling water pollution from dairy
farms.
POULTRY
Poultry operations can generally be considered as falling Into
one of three major categories: broilers and layers, ducks, or turkeys.
The volume of ducks and turkeys raised annually 1s not comparable with
the volume of broilers and layers but their unique rearing arrangements
set them apart as probable sources of significant water pollution on
a limited basis.
Broilers and Layers
In providing a general overview of the animal wastes potential for
water pollution, broilers and layers may be discussed in the same
section because of the similarity of their wastes production and handl-
ing problems. A few of the wastes handling methods utilized by the
broiler and layer Industries have been previously discussed 1n the
Regular Dischargers and Intermittent Dischargers sections of this report.
Regular dischargers are a source of major concern because of the
frequency of their discharges. On the other hand, Intermittent dis-
chargers may appear to be less serious threats because of the lower
frequency of discharges. However, taken as a unit throughout the Nation,
Intermittent dischargers pose a serious potential for water pollution.
The nature of Intermittent dischargers means that the enterprises will
at one time or another be guilty of occasional discharges resulting
1n water pollution. For example, spreading wastes too near a water-
course or underdeslgnlng a treatment or detention facility can result
in Intermittent discharges.
Location of Broiler Production
Commercial broiler production 1s presently concentrated 1n the
south central and southeastern part of the United States (Map 7).
In 1968, about 2.6 billion head of commercial broilers were produced
in 42 States. Georgia, Arkansas, Alabama, North Carolina, and
Mississippi were the leading States with a combined broiler production
total of 1.6 billion birds 1n 1968. It 1s, therefore, readily apparent
that broilers have a significant regional water pollution potential.
However, despite this regional concentration, the numbers of broilers
raised in the other areas shown on Map 6 Indicate the necessity of
studying the water pollution potential from broiler enterprises on a
broad geographic base.
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DO
Map 7
Location and Number of Commercial Broilers Produced in 1968, and of Layers
on Hand During October 1969.
////3B9.0
IIhi'""""
ms*
Hawaii—
1.4
1.0
Top number in each State refers to
million head of broilers
Bottom number in each State refers to
million head of layers.
Indicates States producing over 100 million broilers in 1968
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Location of Layers
Layers, like broilers, have a regional concentration but the
regional differences are not as pronounced for the layers (Map 7).
Leading States in the number of layers on hand during October 1969
were California, Georgia, North Carolina, and Arkansas with a combined
total of 94.9 million birds out of the 315.3 million birds for all
States. In addition to the layers are the potential layers on hand
for replacement and flock growth. These potential layers might amount
to an additional 20 percent to the layers on hand. Overall, when the
broilers, layers and potential layers are viewed together, the general
magnitude of potential pollution indicates a need for further
Investigation.
Ducks
Duck raising enterprises utilizing water flowing in a channel
along the duck feeding areas which are staged by bird age have been
previously described 1n this report. The two major problems readily
ascribable to this flowing water system are: (1) wastes are dropped
directly Into the channel by the ducks, and (2) duck wastes are
washed from the feeding areas Into the channel by rainfall. Since
the water flowing through the channel must ultimately be disposed of,
any wastes or pollutants carried by this water are potential water-
course pollutants.
The problem of wastes washing Into the channel can be handled by
diversion of outside runoff water and covering of the feeding areas.
On the other hand, wastes deposited directly Into the channel cannot
be prevented as long as the water Is a necessary part of the rearing
operation. Therefore, the carriage water must be rendered Innocuous
before discharge to a watercourse.
Duck farmers In the Moriches Bay area near Patchogue, New York
along with the Federal and State governments have been developing
measures for controlling pollution from duck wastes. Basic criteria
for treatment of the duck wastes were set at 85 percent removal of
BOD and suspended solids, disinfection of the wastes, and substantial
removal of the phosphates. Experiments have shown that aerated lagoons
and chlorination accomplish the first three objectives but are not
fully satisfactory 1n removing phosphates. Additional research 1s
being completed on phosphate removal techniques applicable to the
lagoon situation and should be available 1n the near future.
Where adequate land 1s available, evidence Indicates that long
detention times 1n an extensive lagoon system can also accomplish the
objectives of disinfection and 85 percent removal of BOD and suspended
solids. Use of lagoons without added aeration reduces the operation
costs of the system but Increases the Investment 1n land and lagoons.
79
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A third possibility for meeting the four standards 1s land disposal of
the waste effluent through a land Irrigation system. Such a system
may be acceptable If the application rates are geared to the crops,
soils, and climatic conditions.
Turkeys
There 1s very little Information presently'available with regard
to turkey raising and Its pollutional effect on watercourses. However,
the rearing of turkeys takes place in confined outdoor areas quite
similar to beef feedlots. Therefore, turkey feeding enterprises are
subject to the same climatic effects as feedlots and should be studied
to determine 1f they are sources of water pollution.
Turkey raising takes place across a wide range of climatic condi-
tions as evidenced by the fact that the two leading turkey producing
States are Minnesota and California (Map 8). Other heavy turkey
producing areas tend to cluster around the Midwest and extend Into the
south central part of the United States.
Since the wastes from turkey enterprises tend to be subject to
runoff, the turkey operations should be Investigated to determine If
they are indeed sources of water pollution. If 1t 1s determined that
the wastes do cause water pollution, the control measures used for
feedlots (e.g., water diversion, detention, covering, etc.) along
with other poultry wastes control measures should be analyzed to
determine their applicability to the turkey enterprises.
SWINE
An earlier section dealing with the general aspects of animal
wastes as they relate to water pollution discusses swine wastes
and proposes that, for purposes of water pollution control analysis,
the swine waste problem be divided Into three components: finishing,
farrowing, and farrowing-finishing. These earlier sections also
point out that swine operations are readily adaptable to water flush-
Ing systems and that water flushing is often desirable from the
enterprise's standpoint. As a result, many swine operations fall into
the regular discharger category and have a high potential for water
pollution. Other swine operations may utilize outdoor farrowing and
finishing areas which tend to be similar to feedlots In runoff poten-
tial and fall 1n the Intermittent to never categories.
Location of Swine Enterprises
The number of hogs on farms by States on January 1, 1969, is an
Indicator of the concentrations of hog enterprises and, consequently,
an Indicator of areas of potential water pollution from swine enter-
prises. Although these Inventory numbers are helpful in Indicating
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Map 8
Location and Number of Turkeys Raised in 1968
Numbers shown in each State
are rounded and refer to million
head of turkeys
Shaded areas indicate States producing
over five million birds in 1968
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major potential problem areas, they provide very little help In assess-
ing actual pollution from swine enterprises. Total wastes produced by
these hogs could be estimated using average wastes produced per animal
figures. However, the value of such figures 1s limited because they
only apply to a certain given point 1n time and because the total
wastes produced by swine probably have very little to do with the
amount of actual water pollution occurring at present.
The major swine producing and finishing areas cluster around the
Midwest and reach Into the southeastern United States (Hap 9).
The leading State In number of hogs on farms on January 1, 1969,
was Iowa with nearly 15 million head. Other leading States Include
Illinois with about seven million head and Indiana and Missouri with
over four million head each. Outside of the midwestern and south-
eastern areas total hog numbers are relatively small and the likelihood
of extensive water pollution from swine enterprises 1n these areas
1s low. However, there may still be many enterprises contributing
their wastes to watercourses and the maximum extent of pollution
from these contributions 1s dependent, in part, upon the local concen-
trations of hog numbers. Of course, this Is true for all of the States
and future studies should pinpoint local hog concentrations within
the State boundaries. These locations, coupled with Information as to
the type of hog enterprise, weather conditions, and alternative pollu-
tion control methods, may then be used as the base for estimating
costs of controlling water pollution from swine enterprises.
Common Control Methods
Common control methods, of varying costs, degrees of effectiveness
and acceptance, are now In use. These Include lagoons, covered opera-
tions with biological treatment in oxidation ditches, covered
operations with liquid manure handling systems, and operations located
to preclude runoff reaching watercourses. Each of these methods has
Its own special advantages and disadvantages In terms of the enterprise
and as it relates to water pollution control. Lagoons, for example,
may be effective 1n reducing biological loadings but do little for
color or nutrient loadings. On the other hand, oxidation ditches can
be virtually closed systems eliminating water quality problems but
the operation costs are relatively high. Covered operations with
mechanical cleaning can have low monetary costs for equipment and
operation but the amount of labor required may limit the size of the
operation and disposal practices must be limited to prevent pollution
from field runoff.
From this brief summary of a few of the common control methods
1t 1s readily apparent that the type of water pollution control method
adopted 1s dependent upon several conditions and varies with the condi-
tions present 1n any particular enterprise. However, there are enough
82
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Map 9
Number and Location of Hogs on Farms January 1,1969
Alaska- 1.1
Hawaii- 64
Numbers in each State refer to thousand head
Shaded area indicates States with over one million head
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common characteristics among groups of enterprises to permit aggrega-
tion of numbers of hogs and enterprises, and of control methods within
these groups so that total pollution control costs can be estimated
once future studies provide the necessary base data.
SHEEP
There is little Information presently available that can be used
to measure the Impact of sheep wastes on water pollution. The range
type nature of many sheep enterprises probably places them in the
seldom to never discharger categories discussed in earlier sections
of this report. However* there may well be many cases of sheep wastes
contributing to water pollution and these situations must ultimately
be controlled.
Map 10 shows the relative concentrations by State of sheep and
lambs on farms on January 1, 1969. Although the States with over one
million head of sheep and lambs are singled out to reveal the areas
of heaviest concentrations, the relationship between these areas and
water pollution potential is unknown at this time.
84
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Map 10
Number and Location of Sheep and Lambs on Farms January 1,1969
Cc
A R | 7 '•'•'•''*•*'-*"•'ViVi*-''**'-'-V*'-'**'*i*
-
-
;
s
o Alaska- 27.0
R
« _
s Numbers in each State represent thousand head.
I Shaded area indicates States with over one million head.
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