LAND APPLICATION OF
WASTEWATER IN
AUSTRALIA
The Werribee Form System
Melborne and Metropolitan Board of Works
Victoria, Australia
BELFORD L. SEABROOK
Professional Engineer
MAY 1975
U.S. ENVIRONMENTAL PROTECTION AGENCY
Municipal Construction Division
Office of Water Program Operations
Washington/ D.C. 20460
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ABBREVIATIONS
Board - MMBW-Melbourne and Metropolitan Board of Works
BOD - biochemical oxygen demand
cm - centimeter
TOD - chemical oxygen demand
l''arm - Werribee 1 arm soil treatment system of MMBW
in. - inch
MMBW - Melbourne and Metropolitan Board of Works
N - nitrogen
mgd - million gallons per day
mg/1 - milligrams per litter
ppm - parts per million
P - phosphorus
SS - suspended solids
ERMS
Conventional secondary treatment - Reduction of pollutant concen-
trations in Wastewater ky^p]^^ cnemi;eal^r;biblo^ical menas.
Crop irrigation - Application on land of water to meet the growth
needs of plants.
E vapot ran spi ration - The unit amount of water used on a given area
in transpiration, building of plant tissue, and evaporated from ad-
jacent soil, snow, or intercepted precipitation in any specified time,
Grass filtration - Same as overland flow.
Land application or Land Treatment - The discharge of wastewater
onto the soil for treatment, reuse or crop irrigation.
Overland flow - Wastewater treatment by grass filtration, flooding
or spray- runoff, in which wastewater is applied onto gently sloping,
relatively impermeable soil which has been planted to vegetation,
Biological oxidation occurs as the wastewater flows over the ground
and makes contact with the biota in the vegetative litter.
Raw sewage - Untreated wastewater,
Secondary treatment - Something more than primary treatment,
usually treatment By physical, chemical, or biological means such
as trickling filters, activated sludge, or chemical precipitation
and filtration, Sometimes called mechanical treatment,
CONVERSIONS
1 Acre feet * 3, 060, 000 US gallons, or 2, 550, 000 Imperial gallons
A$ 5 Australian dollars
A$l. 00 - US$1.35
US$1.00 = A$0,74
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r r
WESTERN
CATCHMENT
r
FARM
M.M.t.W. H.MINMC
DANDENONG
LEASTERN
VALLEY
PORT PHILLIP BAY
MELBOURNE AND METROPOLITAN AREA
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SUMMARY
This report concerns the Werribee Farm soil treatment
area operated by the Melbourne and Metropolitan Board of Works
(MMBW). The Board (MMBW) was constituted in 1890 by an Act
of the Parliment of Victoria to develop and operate a system of
main and general sewerage for the metropolis. James Mansergh,
an eminent sanitation engineer from London, submitted eight al-
ternative schemes, five of which involved treatment by land; two,
disposal by ocean outfall; and one, by chemical precipitation.
Mansergh stated that the Werribee site was situated for land puri-
fication of sewage because it was exceptionally dry and had an
abnormally low rainfall compared with surrounding districts. His
recommendation, based on proven success in England, and on the
benefit of irrigation in an area of low rainfall, was for disposal
by flood irrigation on prepared land without prior treatment of
the sewage. Even today raw sewage is used at the Werribee
Farm. Work began in 1892; and in 1897, the sewage from the
first property (a hotel) was delivered to the system. Mansergh,
of course, could not have foreseen Melbourne's rapid population
growth nor the demands that would be placed on the Werribee
Farm within 30 years of its establishment. By the late 1930's,
the heavy waste loadings had made it necessary to not only en-
large the area of the Farm, but also to complement land filtration
(called crop irrigation in the United States) with sedimentation,
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grass filtration (overland flow) and lagooning. Despite these ad-
ditions to the Farm's land treatment operations, the 1897 system
remains, to this day, basically as it was originally conceived
and build. Even the introduction of the South-Eastern Sewerage
System (in 1974) on the opposite side of Port Phillip Bay fulfills
Mansergh's original concept of a disposal system serving each
side of the Bay, The relationship of the Werribee Farm to the
South-Eastern Sewerage System can be seen on the accompanying
map of the Melbourne Metropolitan area. In June 1974, there were
some 800,000 ratepayers (population 1, 880, 000) being served by
the Board. The Werribee Farm serves about 95 percent of the
sewered areas in the metropolis. The balance is served by four
other major and two minor systems.
For the fiscal year ending June 1974, the annual per capita
cost of the Board's Werribee system was A$l,13 (US$1, 53) for
95 percent of the population of 1, 880, 000. This figure includes
all current costs. The capital costs of the land and the original
construction were written off years ago. The average daily flow
to the Werribee Farm is 125 million British Imperial gallons
(ISO mgd US).
The principal problem with land treatment at MMBW is caused
by the increasing hydraulic load per capita coupled with the in-
er©a@ing population served by the system.
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Because the cost of purification at Werribee is substantially less
than by mechanical treatment, as well as because the quality of the
effluent from Werribee is higher, the MMBW intends to continue to
utilize land treatment to the extent possible. However, as the popu-
lations of Melbourne and Geelong increase, and the urban areas extend
outward toward the Werribee Farm, the acquisition of additional land
adjacent to Werribee has not been possible. As a consequence, MMBW
is constructing conventional secondary mechanical treatment works and
plans to transfer about 45% of the hydrological load from the Werribee
Farm to the new South East mechanical system. In spite of this,
by 1980/81 the MMBW estimates that the pollutant loading will return
to the maximum that the Werribee Farm, as presently operated, can
handle.
Currently all sewage to the Werribee Farm is raw sewage. This
has been the practice since land treatment was started in 1897. How-
ever, in order to provide increased treatment capacity at Werribee,
MMBW is giving consideration to using a combination of part primary
to full secondary treatment in conjunction with biological processes.
In summary, the MMBW Werribee system is in full operation, is
most successful, is substantially lower in annual per capita cost of
operations, and MMBW intends to continue to operate its land treat-
ment facilities indefinitely.
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LAND TREATMENT. IN UNITED STATES
The Federal Water Pollution Control Act Amendments of 1972
(Public Law 92-500), the legislative history of the Act, and the
regulations which have been issused in accordance with the pro-
visions of the Act, provide the statutory basis for consideration
'and funding of land-application systems in the treatment of municipal
wastewater.
The rationale and goals within which land-application systems
are to be considered are contained in the following sections of the
Act:
Section 208 - Areawide Waste Treatment Management
Section 201 - Facilities Planning
Section 304 - Best Practicable Treatment Technology (BPT)
Section 212 - Cost Effectiveness Analysis
These sections, together with the regulations pertaining to these
sections of the Act, and the Program Memoranda to the EPA Regional
Administrators, have resulted in a growing interest in the United
States in soil treatment systems for municipal wastewater. The
EPA Deputy Administrator, on November 1, 1974, wrote to the
Regional Administrators urging them to ascertain that the regional
review of application for construction of publicly-owned treatment
works requires that land application of wastewater be considered
as an alternative waste management system. The DA said that the
RA's should refuse to fund projects using other systems of waste
treatment if it can be demonstrated that land treatment is the most
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cost-effective alternative; is consistent with the environmental
assessment; and, in other aspects, satisfies applicable tests.
This memorandum is attached hereto.
In addition to the potential for being the most cost effective
treatment alternative (note the MMBW total annual per capita cost
for the fiscal year ending June 1974 is US$1. 53 for sewage treat-
ment serving 95 percent of the population of 1.88 million people),
another significant reason for the growing interest in land treat-
ment is that PL 92-500 gives authority to the EPA Construction
Grants Program to fund publicly-owned soil treatment systems
including the acquisition of the land that will be an integral part
of the treatment process -- Section 212(2)(A).
The EPA report, entitled, Survey of Facilities Using Land
Application of Wastewater by American Public Works Association,
identifies certain existing soil treatment systems that were started
in the United States as early as 1880. However, these early systems
started as disposal projects, and there is a major gap in reliable
design data and information. The consequences of this dearth of
design information has handicapped the construction grants pro-
gram, primarily because of the lack of standard criteria. Another
deterrent has been the lack of information concerning potential
health hazards from soil treatment systems.
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Strangely, however, the same dearth of information concerning
potential health hazards from secondary treatment and discharge
to surface waters has not slowed the demand for the more costly
conventional reinforced concrete treatment works. In fact, it seems
to me that there could be far greater health hazards from secondary
discharge into surface waters because these waters are so often used
as sources of potable water by other downstream municipalities.
INTRODUCTION
There are 17 residences located in the midst of the Werribee
Farm which are used by farm employees and their families. I visited
several of the homes of farm employees, met members of their
families including the children, and enjoyed a Sunday picnic on the
front lawn of one of these residences. There is no evidence of health
hazards caused by sewage irrigation in the adjacent fields, and no
concern was expressed by the occupants of these houses about po-
tential health hazards. To the foreign observer that I was, these
residences appeared no different than any other farm residences,
and their occupants appeared no different than any other farm families,
either in Australia or in the United States. Incidentally, on previous
trips to Australia I visited many rural communities in every
Australian state, except the Northern Territory, and I lived and
worked on farms in the United States over a period of several decades.
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In my judgment, the farm houses located on the Werribee
Farm are better than the majority of farm dwellings in the
United States, and the occupants are living under better health
conditions than some of their counterparts in both Australia
and the U. S.
The Werribee Farm soil treatment system is the outstanding
project in Australia from the standpoints of the lowest annual
operating costs, success, size and extent of experience with the
use of wastewater effluents. The map of Melbourne on page 2
shows the relationship of the Board's Werribee Farm to Port
Phillip Bay and the surrounding Melbourne and Metropolitan
areas. The South-Eastern Purification Plant (secondary treat-
ment) is also shown on this map.
The Farm has served the residents of Melbourne as a re-
liable and economical means of wastewater treatment and utiliza-
tion since 1897. The use of wastewater for irrigation of pasture
land, and the subsequent production of cattle and sheep, is an
outstanding example of reclamation and conservation. Over the
years, however, population and industry have increased greatly.
As a result* the Farm is no longer able to cope satisfactorily
with the volumetric and organic loadings imposed upon it.
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LIVESTOCK AND THE TREATMENT PROCESS
.The livestock at the Farm are not only money-earners from the
point of view of meat, they are also an essential part of the treatment
operations. . .
Because wastewater treated at the Farm contains a high proportion
o! natural fertilizers, it promotes a prolific growth of pasture; but
since crop irrigation is an efficient method only if the vegetation cover
is kept short, cattle and sheep are effectively used to "mow"the grass.
Sheep were introduced to the Farm in 1900 and cattle some 10 years
later. In the years since, the Board has sold more than 1.7 million
sheep and well over a quarter million head of beef cattle from its
Angus and Hereford herds.
Grazing of sheep is on a seasonal basis, and the Board buys the
animals in various parts of the southeastern cornerof Australia to fatten
them for market. The beef cattle, on the other hand, are bred on the
Farm and remain there until they are ready for sale. The most suitable
animals are retained for breeding and the others are sold as prime
meat on the hoof at Newmarket, Melbourne.
Sales of cattle are subject to the condition that they must be immed-
iately slaughtered at an abattoir in the Melbourne metropolitan area,
and those killed must undergo rigid inspection. This condition, imposed
in the 1920'sby the Parliament of Victoria, was a political one obtained
by the commercial beef producers and had no health hazard basis.
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Diversion to the South Eastern Purification Plant of a portion of the
wastewater now reaching the Farm will ease, but not solve', the situation
for a number of years, but continued growth in the Western Catchment
will produce Hows and loadings well in excess of those at present. For
example, the loading of biochemical oxygen demand will total about
750, 000 pounds per day before completion of the South Eastern Purifi-
cation Plant; diversion to that plant will remove slightly over 100, 000
pounds per day; increased development in the Western Catchment will
gain this amount back before 1985; and, less than fifty years hence, the
total loading may exceed 1, 000, 000 pounds per day.
The Farm system serves about 95 percent of the sewered areas in
the metropolis. Except for wastes from the greater part of the Munici-
pality of Sunshine, which are discharged directly in the Main Outfall
Sewer, and from William is town, which enter the main system at Spots-
wood, all wastes collected by the Farm system flow by gravity through
two main sewers - the North Yarra and the Hobsons Bay Main Sewers
which unite at Spotswood.
The combined flow then continues for 2 1/4 miles via a 9 ft. 3 in.
diameter trunk sewer which terminates at the Brooklyn pumping station.
Flows in this sewer enter the pumping station through two penstocks,
or control gates, set at the bottom of a well, 144 ft. deep and 22 ft.
in diameter. The penstocks control the flow into each of two protective
screen wells, 156 ft. deep and 22 ft. in diameter.
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From each screen well, the flow continues to its corresponding
pump well.
The two pump wells are each 178 ft. deep (internal) and 66 ft. in
diameter. Four pumps are installed in each well, and the eight pumps
are driven by individual electric motors, the combined rating of which
totals 12, 800 horsepower. Each pump has a maximum capacity of
42 mgd (50 mgd, US).
When Melbourne's sewerage scheme was originally designed, Port
Phillip Bay was selected as the most suitable body of water for the
final disposal of the effluents after purification.
The most suitable method of purification known in European coun-
tries at the time was land treatment, and the site chosen near Werribee,
between the Geelong Road and Port Phillip Bay, possessed all the
factors essential for the satisfactory operation of the method--ample
area, reasonable isolation, suitable soil and climatic conditions.
An area of 8, 847 acres was acquired, and the preparatory work
began in 1893. As the city has grown, it has been necessary to expand
the Farm area, and today it covers 27, 000 acres or nearly 42 square
miles.
The Board's Farm at Werribee begain operating in 1897. By 1900,
it handleda wastewater flow averaging 12 million gallons per day (14.4
mgd, US). Since that time, the flow has increased as a result of
growth of population and industry in the metropolitan area, and at present,
averages about 125 mgd (150 mgd, US or 568,650 cubic meters). The
mode of operation, originally begun as irrigation of 6,000 acres of
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land to produce pasturage for cattle and sheep, has been expanded
over the years to include all-year use of anaerobic and aerobic lagoons,
sedimentation basins and open sludge digestion lagoons, as well as
overland flow (grass filtration) from mid-autumn to mid-spring when
irrigation demands are minimal or nil.
Rainfall at the Farm averages 19 in. (48.3 cm.) annually, of which
about 12. 5 in. (32. 2 cm. ) of evenly distributed rainfall can be expected
during the crop irrigation season; whereas, the evapotranspirational
potential during the same period averages about 35.6 in. (90.4 cm. ),
indicating that a major portion of the annual application of 44 in. (112
cm. ) of sewage effluent has evaporated. The daily flows of raw sewage
arriving at the Farm vary greatly depending upon rainfall. The current
average flow is about 150 mgd (568, 650 cubic meters); however, during
storm periods peak flows as high as 300 mgd (1, 140, 000 cubic meters)
may occur. Temperature variations are from a low of 40 degrees
F (4.4 degrees C) in winter to a high of 112 degrees F (44 degrees
C) in summer.
SOIL CHARACTERISTICS
There is no detailed classification of the Farm soils, but the surface
of the soil profile consists of a red-brown silt clay loam which is slightly
acid. Clay occurs at a depth of about 12 in. (30 cm.). The depth of
the clay subsoil is substantial, extending far below any core samples
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that, have: been recorded. The report issued by the U.S. Army Corps
ol' Engineers in .lai<'iary 197-4. entitled, "Selected Chemical Character-
istics of Soils, Forages, and Drainage Water- from the Sewage Farm
Serving Melbourne. Australia", contains much detail on soil and forage
characteristics.
GENERAL OBSERVATIONS
Many aspects of the Farm operations are praiseworthy. Wide-
spread recognition of the need to conserve or reuse natural resources
has evolved only in recent years; however, since 1910 the Farm has
reused wastewater from Melbourne I'or irrigation of pasture land. This
process has converted land of little potential for agriculture to prime
pasture which now carries over 20,000 cattle and 10,000 sheep. By
using the natural resources, water and land, the Farm has marketed
more than .270, 000 cattle and I, 500, 000 sheep since 1910. Taking into
account the equipment and manpower costs related to livestock pro-
duction, the net returns from sales presently average over A$500, 000
(US$675, 000) per year and significantly reduce the costs directly associ-
ated with sewage purification at the Farm. Thus, from conservation
and financial standpoints, the Farm represents a valuable resource
to the residents of Melbourne.
Initial diversions from the Farm system to the Board's South
Eastern 'Purification Plant, are scheduled for 1975. Although this will
result in lower loadings at the Farm in the short-term, growth of popu-
lation and industry tributary to the Farm will generate additional load-
ings well in excess of those diverted.
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KAH.M Oi'l-IUATIONS
It is'logical to consider operations at the Farm from two stand-
points: first, in relation'to its' primary function for wastewater
treatment and second, in terms of its use for livestock production.
In addition, approximately three-fourths of the Farm area is a de-
clared Wildlife Sanctuary and provides a habitat for a variety of water-
fowl and other birds and animals.
WASTEWATER TREATMENT
In the early years, treatment at the Farm consisted of land fil-
tration by irrigation of pasture land with the underflow collected in
drainage channels and discharged to Port Phillip Bay. During winter,
wastewater flows in excess of the land's capacity were held in shallow
lagoons along the foreshore. Increasing flows during the intervening
70 years have lead to increasing the size of the Farm from about
6.000 acres to nearly 27.000 acres. Of this total, about 17, 000 acres
are used for some form of treatment, and the balance is devoted to
dry grazing, roads, buildings, yards, and other purposes.
The use of grass filtration (overland flow) during winter months
began about 1928 and made it possible to phase out the shallow lagoons
along the foreshore previously used for winter flows.
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Anaerobic and aerobic lagoons were introduced about 1935. Lagoons
can handle higher loadings of organic matter than either of the two other
methods of treatment, and as a result, their area has been increased
.greatly in recent years to match increases in loadings. For purposes
of comparison, numerical values for the years ending 30 June 1959
and 30 June 1971 are listed in Table A and the monthly variations during
each year are shown on Figures 1 and 2.
Table A. Loadings and Treatment Processes, 1959 and 1971
~~~~~~ Year Ending 30 June
1971
Total wastewater volume, milllion
gallons (US)
35,160
50,900
Average BODS, milligrams per liter
Pounds per day
Crop irrigation, million gallons (US)
Percent of total
Overland flow, million gallons (US)
Percent of total
Lagoons, million gallons (US)
Percent of total
451
384,000
13,320
38
13,680
39
8,160
23
588
661,000
10,680
21
15,360
30
24, 960
49
On arrival at the Farm, the wastewater is distributed to the various
treatment areas through a network of channels. Three methods of puri-
fication are used. Short explanations of each method along with perti-
nent comments follow.
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Figure 1: Areas used for various treatment methods during 1958/59 at Werribee Farm
I6O
JULY
AUG
SEPT OCT
NOV DEC
JAN
MARCH APRIL MAY
JUNE
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Fiqure 2: Areas used for various treatment methods durinn 1970/71 at Werribee Farm
160
AUG SEPT OCT NOV OCC JA* FEB MARCH APR:_ MAY JUNE
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Crop Irrigation (land filtration). This is the primary method which
is used throughout the summer. The land filtration areas are carefully
prepared pastures, about 20 acres in exent, and divided- into 50 bays
by low check banks. They are subsoiled, graded evenly and sown with
selected pasture grasses.
The wastewater is applied as in normal flood irrigation. Every
1H-20 days, each block is covered to a depth of about 4 in. In all,
about 600 acres are irrigated each day. The wastewater filters through
the soil and when purified seeps in«to deep, earth drains.
The periodic irrigation of pastures with wastes containing a large
proportion of fertilizing materials promotes a very vigorous growth of
grass. Rotational.grazing-by she^p., eat-tle> and some horses is essential
to maintain these pastures in a; condition suitable for continued waste-
water purification.
Application rates for crpp irrigation are controlled by the ability of
the soil to absorb water, rather than by the strength of the wastewater.
I'Jxamination of irrigation records from 1935-1971 shows wastewater
irrigation depths average about 3.5 feet per year and range between
2. 9 and 4. 2 feet per year. In a given year, the application rate depends
on the rainfall pattern and evaporation. Including annual rainfall, the
land receives more than 5 feet of water depth per year. Based on
present wastewater strength, the average application rate amounts
to 30 Ib. of BOD per acre each day.
Crop irrigation is quite effective in reducing the concentrations of
many chemical constituents of concern in terms of their effects on the
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receiving waters. Compounds of nitrogen, phosphorous, and most
of the heavy metals are reduced dramatically. Table B shows results
.of analyses made on the incoming wastewater and the average for effluent
collected from seven different drainage channels which pick up the
underflow from the irrigation areas.
Table B. Chemical Characteristics of Untreated Wastewater and
Effluent from Crop Irrigation Treatment
Constituent
Organic nitrogen
Ammoniacal nitrogen
Nitrite
Nitrate
Orthophosphate
Total Phosphorous
Sodium
Potassium
Calcium
Magnesium
Copper
Nickel
Chromium
Cadmium
Zinc
Lead
Mercury
mg/L Concentrations
Untreated
Wastewater
14.3
35.0
0.75
0
26.2
32.1
400.0
95.0
65.0
80.0
0.45
0. 20
1.0
0.01
1.3
0.55
0.0015
17
Effluent
1.0
3.2
1.3
0.4
2.6
2.9
770.0
26.0
45.0
107.0
0.07
0.16
0.09
0.006
0.18
0.12
0. 0003
Percent
Removal
93
91
V
•
90
91
-
73
30
-
84
20
90
40
86
78 •
80
Source: MMBW Analyses on samples collected 17 May 1972.
' Ij Concentrations of nitrogen compounds expressed as N; phosphorous
~ compounds as PCX ; all other as the particular element.
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Overland I'low (grass nitration). This process is used in purifying
the greater part of the normal winter flow when reduced evaporation
makes crop irrigation impractical. In this method, the wastewater is
first directed into sedimentation tanks, and when the sludge has settled,
the water is allowed to flow slowly but continuously over graded areas
on which Italian rye grass supplements the natural herbage to make
a dense growth. The plants act as a filter in which microorganisms
absorb the organic matter in the wastewater so that by the time it
reaches the drain, it has the required standard of purity. The overland
Row areas are grazed only in the summer when they are not needed
for purification purposes.
Detention times are about 2 days. In contrast with crop irrigation,
loading rates are governed by wastewater strength rather than by volume.
Because of the short detention time, daily loadings rather than long
term ones are important. Maximum loadings of about 90 Ib. of BOD per
acre each day can be handled. In practice, however, it is more con-
venient to control application by regulating wastewater volume to the
overland flow areas. To keep BOD loading rates within the maximum,
the volumetric rate of application of sedimented wastewater is held
at about 1 mgd per 50 acres. Experience at theWerribee Farmindicates
that daily BOD application rates average about 70 Ib. per acre.
Oxidation Ponds Treatment. This process operates throughout
the year to handle the balance of the normal flows which cannot be
treated by the other methods and also copes with the wet weather excess
flows. During this treatment, the wastes flow slowly through large
areas of shallow ponds where purification is effected by oxygen which
is partly absorbed from the atmosphere and partly provided by algae
• /
in the presence of sunlight. /
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Oxidation Ponds. In the lagoon treatment process, wastewater
passes through anaerobic lagoons and then through aerobic lagoons.
Detention times, relatively short in the former and long in the latter,
depend on the rate of wastewater addition, but generally are about
one month. BOD loading rates vary with Wastewater strength and the
volume added. Experience indicates that average loading rates of
about 60 Ib. of BOD per acre per day can be handled in winter, while
about 100 Ib. per day can be handled in summer when photosynthetic
activity is greater due to higher temperatures and longer hours of
sunlight.
Treatment Efficiency. As shown by the annual averages on Table
C, the three treatment processes vary in their ability to remove
organic matter and other chemical constituents in raw wastewater.
The crop irrigation process is the most effective, but as noted above,
area loading rates are low and only about 20 percent of the year's
flow at the Farm can be treated by this process. The reductions
it achieves in compounds of nitrogen and phosphorous are particularly-
noteworthy. In raw wastewater given crop irrigation treatment, only
5 pounds pass through the top soil and are found in the effluent.
In contrast, the comparable values for overland flow are 40 pounds
of nitrogen and 65 pounds of phosphorous, while for lagoons, the
values are 65 and 70 pounds respectively. In terms of nitrogen
removal, crop irrigation is 8 times more effective than overland flow
and 13 times more effective than lagoons. Similarly, for phosphorous
removal, it is 13 and 14 times more effective, according to MMBW.
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Table C. Estimated Performance by Treatment Processes
on Annual Basis
Characteristics
Percent of total flow
treated
Percent removal
BOD
Suspended solids
Total nitrogen
Total phosphorous
Detergent
E. Coli
Method of Treatment
Crop Irrigation
20
98
97
95
95
80
98
Overland Flow
30
96
95
60
35
50
99. 5
Lagoon System
50
94
87
40
30
30
99.8
Odors. Sources of odors at the Farm have been studied intensively
several times, particularly in 1950, 1966, and 1968-1970. The 1966
work disclosed that the "odor potential", based on measured hydrogen
sulphide emissions, was four times greater in winter than in summer,
and that sedimentation and sludge digestion basins, lagoons, and over-
land flow areas were the principal sources. Crop irrigation areas
and effluent channels were found to be relatively insignificant sources.
At each of the major sources, the treatment processes are, or are
prone to be, anaerobic. Sedimentation and sludge digestion basins
are open, and hydrogen sulphide and other odorous gases are readily
released to the atmosphere. The anaerobic lagoons, an inherent part
of the lagoon system presently used, are economic on space due to
the high BOD loading which they can handle, but are the odorous
component. During winter, the area of anaerobic lagoons is greater
than in summer, which leads to the release of greater quantities of
hydrogen sulphide. In the 1966 tests, this gas was detected over
about half of the area used for overland flow.
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Livestock Production. Since 1910, the Farm has operated a commercial
beef enterprise, producing 20-22 month old steers and fat cull cows
for the Melbourne market. During the past 62 years, over 270, 000
cattle have been marketed. Since 1946, almost the entire cattle output
has been bred and raised on the Farm. In addition, sheep are brought
in and fattened on the Farm, and during the same period, more than
.1.5 million have been marketed.
Early prohibitions against marketing the cattle for human con-
sumption because of the incidence of beef measles (cysticercosis)
were overcome in 1946 by the adoption of the carcass inspection and
branding program. In addition, the Farm stock has built up an im- .
munity, and market rejection for this reason is rare --29 rejections
out of over 116,000 cattle marketed since 1946.
In summary, the principal purposes of operating the Werribee
l-'arm have been to renovate the sewage effluents and to recover re-
sources that could be converted into cash. Research for the sake
of research alone has not been a major factor, although some elements
of research have been done to seek out solutions to specific problems.
The Werribee Farm has 31 test wells for monitoring the influent
(daily) and the effluent (twice weekly) to Port Phillip Bay.
The Board has some information on soil analyses at certain loca-
tions. In certain small areas affected by salt accumulation caused
by groundwater, there is some information. There is limited data
on receiving water quality, odors, and potential health hazards, as
well as information on BOD, SS, COD, pH, fecal coli, P, total N,
nitrate, nitrite and Cl.
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CORPS OF ENGINEERS REPORT
In May 1972 a team from the U.S. Army Corp of Engineers
made an intensive inspection and study of the Werribee Farm
land treatment system. An important aspect, among others,
was to learn as much as possible about long term responses
of the soil/plant ecosystem to sewage applications. Accordingly,
soil and plant samples were collected and analyzed for their
nutrient and heavy metal contents.
A report published by the Corps in January 1974, entitled,
"Selected Chemical Characteristics of Soils, Forages, and
Drainage Water from the Sewage Farm Serving Melbourne,
Australia", presents and discusses the findings of this study.
Specifically, data resulting from the analyses of soil and plant
samples, from sites under irrigation for periods of 48 to 73
years, is discussed in relation to a control sample, length
of time under irrigation, resultant water quality produced by the
treatment system, and expected ranges of constituent concen-
trations found in soils .and plants from the literature on the
subject. A copy of the Corps report is attached hereto.
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MOVIE
The MMBW has produced a 16mm film, entitled Werribee - In
Harmony with Nature, showing the land treatment operations at the
Werribee Farm. This is a nontechnical film, 773ft. in length. Copies
can be purchased from the MMBW. EPA has ordered 10 copies of
this film, one for each Regional Office. Persons wishing to buy a
copy should address their inquiries to James B. MacPherson, Manager,
Werribee Farm, Melbourne and Metropolitan Board of Works, 625
Little Collins Street, Melbourne, Victoria 3001, Australia.
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REFERENCES
1. Melbourne and Metropolitan Board of Works, Reports, Publicity
Brochures, Newsletters, Staff Newspaper, Unpublished Memoranda,
Calculations, Lists, Fact Sheets, Charts, Sewerage Committee
Notes, Board of Works Notice Papers, and Interviews with Board
Officials, Employees and Specialists.
2. Survey of Facilities Using Land Application of Wastewater, Prepared
by American Public Works Association, July 1973. No. EPA-
430/9-73-006. National Technical Information Service No.
PB-227-351-A/S. U.S. Government Printing Office Stock No.
5501-00666; Cat. No. EP2.2.-W28/4.
3. Article, Waste into Wealth, Water Spectrum 1972.
4. Report, Program for Development of a Master Plan for Water Quality
Management at the Board's Farm, March 1973, by Caldwell
Conriell Engineers.
5. Data and statistics from certain Principal Persons Interviewed.
6. Data and statistics from Dr. Thomas D. Hinesly, University of
Illinois.
7. Notes from personal observations during site visits.
ATTACHMENTS
1. Memorandum from EPA Deputy Administrator to RA's, Nov. 1, 1974.
2. Report, U.S. Army Corps of Engineers, January 1974 "Selected
Chemical Characteristics of Soils, Forages, and Drainage Water
from the Sewage Farm Serving Melbourne, Australia".
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
•SUBJECT.:: Land Treatment
DATE: November 1, 1974
FROM: Deputy Administrator I si John Quarles
TO: Regional Administrators
The purpose of this memorandum is to express my concern that
EPA must do a better job in assuring that land treatment is given
full and adequate consideration as a possible method for municipal
sewage treatment in projects funded with Federal grants.
Land application of wastewaters is practiced successfully and
extensively in the United States. Many land treatment systems
have been in continuous use since 1900. It is apparent from this
long-term experience and documented research work that land treat-
merit technology is a viable alternative to be considered as part of
waste management systems.
"••.-. In section 201 of the Federal Water Pollution Control Act
Amendments of 1972, it declares that:
"Waste treatment management plans and practices shall
provide for the application of the best practical waste
treatment technology before any discharge into receiving
waters, including ^reclaiming and recycling of water, and
confined disposal of pollutants so they will not migrate to
cause water or other environmental pollution and shall
provide for consideration of advance waste treatment
techniques".
Pursuant to section 304(d)(2), which directs EPA to publish in-
formation on alternative treatment management techniques and systems
available to implement section 201, the document "Alternative Waste
Management Techniques for Best Practicable Waste Treatment" was
published. Therein it considers land application as a viable
alternative for best practicable waste treatment.
In addition, the Cost-Effectiveness Analysis Regulations
which apply to all projects subject to best practicable treatment
state that:
"All feasible alternative waste management systems
shall be initially identified. These alternatives should
include systems discharging to receiving waters, systems
using land or surface disposal techniques, and systems
employing the reuse of wastewater".
EPA Form 1320-6 (Rev. 6-72)
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The above requirements shall be met for all projects awarded
after .June 30, 1974. This means that land treatment must be con-
sidered in the basic selection of method for waste treatment.
I urge that you ascertain that your regional review of appli-
cation for construction of publicly-owned treatment works require that
land application be considered as an alternative waste management
system. If it can be demonstrated that land treatment is the most
cost-effective alternative, is consistent with the environmental as-
sessment, and in other aspects satisfies applicable tests, the Region
should insist that land treatment be used and should refuse to fund
projects using other systems of waste treatment.
Your director of Water Programs Division has received the draft
document "Evaluation of Land Application Systems". This document
should be utilized during the review process. Additional assistance
can be obtained by contacting the Municipal Construction Division
(OWPO), the Municipal Technology Division (ORD), or the Robert
S. Kerr Laboratory (ORD).
In order to promulgate proper consideration of land treatment
systems by future grant applicants I suggest that the Regional Office
provide opportunity for public awareness of land treatment tech-
nology. As an example, Region III is planning a two day symposium
November 20-21, 1974 at the University of Delaware to highlight
land application technology. The idea for the symposium originated
in- the Regional Office and was planned cooperatively between the
regional staff and Office of Water Program Operations headquarters
staff. The objective of the symposium is to clarify the technical and
policy issues involved and to chart directions for future decisions
on land treatment techniques. The symposium will provide useful
information to over 300 engineers, scientists, public officials and
private citizens. This technique or a similar one could be used by
your region to emphasize consideration of land treatment.
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