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SYDNEY is beginning to reap the bitter fruits of its cheap and inadequate
treatment of sewage. Pollution and contamination of the city’s beaches and
marine life have stained the region’s reputation as a healthy resort and
damaged the local fishing industry. Early this year, at the height of the
summer season, deposits of raw sewage made Bondi Beach, Australia’s third
largest tourist attraction, unsafe for bathing two days out of five. This
was the verdict of the New South Wales Health Department. It followed several
studies over the past few years that have revealed high levels of organochlorines
and mercury in fish caught near the sewage outfalls. These chemicals, which
are still used in industry and agriculture, are known or suspected carcinogens.
The outfalls are sited on headlands, submerged in shallow water at the bottom
of cliffs and close to the beaches.

The economic and legal consequences of the pollution have already extracted
their toll. Last year, beach shops were doing less business and a drop in
fish sales, down by 30 to 40 per cent, was costing the industry an estimated
A$500 000 (Pounds sterling 250 000) a week. Early in the summer, the travel
industry magazine, Travelweek, warned that tourists could sue on the grounds
that Sydney beaches were being misrepresented in advertisements. Lawyers
advised Waverley Municipal Council, which is responsible for Bondi Beach,
to erect permanent warning signs on beaches about the risk to bathers’ health.
The council has not yet done this.

Sydney discharges its sewage from three main outfalls and from four
minor ones (see map). The three large outfalls cause most concern because
of the enormous quantity of effluent going through them: the outfalls serve
a population of around two and a quarter million and yet they carry enough
for well over four million people. The reason is the high proportion of
industrial waste in the sewage – more than 40 per cent.

The largest outfall, on the northern headland of Malabar Beach, a few
kilometres south of Bondi, discharges 640 million litres of sewage a day
in dry weather. (When it rains, some flood water, or storm water, also seeps
into the sewers.) Pollution has permanently closed the beach to bathers.
The second outfall, on the northern headland of Bondi Beach, discharges
165 million litres of sewage a day. These two outfalls can contaminate every
beach between Malabar and Bondi; which ones are polluted depends on the
direction of the wind. The third outfall, just north of Sydney harbour,
discharges 325 million litres of sewage a day. It pollutes Sydney’s northern
beaches, particularly the ones at Manly, the city’s second favourite beach
that is just 2 kilometres away.

Most of the sewage receives only primary treatment, which is meant to
remove most of the solids from sewage, before being discharged at the outfalls.
Secondary or tertiary treatment would remove most of the remaining solids
but, in Sydney, secondary treatment is carried out only at some of the small
inland plants and at the Warriewood plant on the coast. Primary treatment
should remove about 60 per cent of the solids in sewage; in Sydney, it extracts
only 10 to 15 per cent. Metal sieves, or screens, catch the larger solids
as the sewage flows through them into large tanks. In the tanks, some of
the remaining solids sink to the bottom as sludge. Other constituents, such
as grease, float to the top as scum. Mechanical arms scrape the scum from
the surface of the tanks for incineration or burial. Except at North Head,
where sludge is incinerated, the outfalls discharge the treated sludge and
sewage into the ocean. This comes to the surface and spreads as a black
slick containing viruses, bacteria, heavy metals and organochlorines. Raw
sewage also reaches the ocean when the treatment works are overloaded.

Regular complaints from local people about the unsightly slicks forced
action from the Sydney Water Board, which is responsible for the city’s
sewerage and water services. Since 1984, the board has been extending the
three main outfalls by between 2 and 4 kilometres into deeper water at a
cost of A$300 million. The first should be in operation by the beginning
of August, the second by December and the third by April next year. According
to the board’s engineers, deeper discharges and new diffusers, which look
like giant shower heads on the ends of the outfalls, will dilute and disperse
the sewage better. The designers of the outfalls are trying to take advantage
of the way the temperature and density of water vary with depth; the colder,
denser water nearer the bottom of the ocean should trap the sewage below
the warmer water closer to the surface. On days when this does happen, deep
ocean currents will be more likely to carry the sewage away from the beaches
than the winds and surface currents that, for half the time, bring the sewage
inshore when it rises to the surface.

The water board chose to build deep-water outfalls because they seemed
to offer an inexpensive way of meeting the standards for water quality set
by the State Pollution Control Commission, the regulatory agency in New
South Wales. But environmentalists and some engineers doubt that the scheme
will stop the pollution. Bob Brain, a retired engineer who worked for the
commission, says that deep water will not dilute the sewage as much as that
predicted by the board and that the discharges may often rise to the ocean’s
surface.

Members of a small research group, called Stop The Ocean Pollution,
are running a campaign to clean up the waters around Sydney. They argue
that industry should not be allowed to use the city’s sewers as a cheap
and convenient way of disposing of its toxic waste. Deep-water outfalls
still leave toxic waste, pathogenic viruses and bacteria in the water, says
the group. Only better treatment of the sewage before discharge, say the
environmentalists, will reduce the danger it poses to swimmers and marine
life .

Not many people took much notice of these warnings until early last
year when news of environmental disasters in the northern hemisphere reached
Sydney. Reports of seal deaths in the North Sea and of syringes (flushed
down toilets by drug abusers) washing up on the beaches of New York quickly
raised the environmental consciousness of local residents. In April last
year, they rallied in record numbers on Bondi Beach for a ‘Turn Back the
Tide’ concert to protest against beach pollution and against the Sydney
Water Board. Around a quarter of a million people turned up, according to
a police estimate.

The first sign of serious problems with the city’s sewerage system came
in January 1989 when the results of a study by the State Pollution Control
Commission into the accumulation of heavy metals and pesticides in fish
were leaked to the Sydney Morning Herald. The study, conducted in 1987,
found very high levels of organochlorines in fish caught near the Malabar
outfall (see Table). The fish were red morwong, or sea bream, which are
territorial and were once a popular dish. The average level of benzene hexachloride
in eight red morwong caught 300 metres from the outfall was 122 times the
limit recommended by the National Health and Medical Research Council, which
sets food standards in Australia. The study also discovered a level of heptachlor
epoxide that was 50 times the NH&MRC limit. Heptachlor epoxide derives
from heptachlor, which is used to kill termites; the commission does not
know where the benzene hexachloride came from.

In 1988, members of the Australian Underwater Federation, an association
of skindivers, complained that fish caught near the outfalls had ‘mushy,
tainted flesh’, but the commission still refused to make public its findings.
After the results were leaked to the press, a ban was placed on fishing
within 500 metres of the outfalls.

The water board disputed the validity of the 1987 study, saying that
it was not unusual for studies of that nature ‘to have high errors associated
with them due to natural variations within the sample population’. In 1988,
the commission organised a second study, using four laboratories this time
instead of one. Although the results indicated lower levels of contamination,
which were still several times the NH&MRC limits, this may have been
because the samples of fish were not caught as close to the outfalls as
they were in the first study. The second study also revealed that the pollution
was more widespread; it discovered contaminated fish as far as 3.5 kilometres
away from the outfalls. The New South Wales Department of Agriculture did
not extend the fishing ban; in fact, last October, it lifted the earlier
restriction.

People became suspicious of seafood, despite assurances from the Fish
Marketing Authority and television pictures of the State Premier, Nick Greiner,
eating fish kebabs. They set more store by a scientist from the Australian
Analytical Laboratories, a private laboratory that is one of several used
by government authorities, who said that he regularly found fish with mercury
levels above the NH&MRC limits.

Fish contamination was not the only problem; swimming was also unsafe.
Between 1983 and 1987, the state health department sampled several beaches
every week for levels of faecal coliform, the organism that lives in the
human gut and is used as an indicator of sewage pollution. The department
based its figures on the geometric mean of three samples taken on the same
day. (A geometric mean is the nth root of the product of n results. It tends
to ‘flatten out’ results that are particularly high and that would otherwise
distort the ‘average’ value.) The department considered that a mean sample
with more than 300 faecal coliform per 100 millilitres of bathing water
was unsafe – a level it found on some beaches as often as four days out
of five.

Previously, the Sydney Water Board had presented a much healthier picture.
This was partly because the board, as instructed by the State Pollution
Control Commission, took a geometric mean of five samples, collected once
every six days over a month. So while the health department used the geometric
mean to ensure that its result represented the state of the ocean on the
day it took the samples, the board produced a result that flattened out
the readings from five separate days. Sewerage authorities around the world
adopt this method but it is not one that gives useful information about
how often beaches are polluted – it conceals days of particularly heavy
pollution much better than an arithmetic mean of samples. (An arithmetic
mean is the sum of the results divided by the number of results.) For instance,
the geometric mean of five results that were 10, 10, 320, 1000 and 10 000
faecal coliform per 100 millilitres is 200; the arithmetic mean is 2268
faecal coliform per 100 millimetres.

News of the health department study prompted almost daily reports from
bathers that they had become sick from swimming at the beaches. Periodic
reports of this type date back to the 1920s; it is indeed bizarre that Sydney
has built up such a popular beach culture despite the common knowledge of
the risks of bathing there. Television channels competed to show the most
disgusting aerial shots of pollution coming from the outfalls. Ron Snape,
a marine biologist and former employee of the water board, said that a report
of tests for heavy metals in marine life, done on his own initiative, had
been heavily rewritten and distorted. Sandy Thomas, the board’s former public
relations manager, accused the board of ‘grossly unethical’ cover-ups on
beach pollution. According to a report in the Sydney Morning Herald in January
1989, Peter Fagan, manager of the board’s Environmental Monitoring Programme,
admitted that the board did not know how much toxic waste was going through
its outfalls. ‘We have started looking at this in the past few weeks,’ he
is reported to have said. Later it emerged, from more leaks to the press,
that the board had successfully opposed attempts to update the standards
for water quality because its new deep-water outfalls would not have met
them.

Last month, the state government published two reports on beach pollution.
One gave preliminary results of Australia’s first epidemiological study
of swimmers; the other cast doubt on the ability of even skilled observers
to detect bacterial pollution by eye. The state health department surveyed
9500 people at 12 beaches in Sydney; 10 days later, it interviewed 3000
of them again over the telephone. The study found that one in three people
who swam in ‘polluted’ water, which the department defined as having more
than 300 faecal coliform per 100 millilitres, reported symptoms of illness
compared with one in six of those who did not swim. The second study reported
that inspectors employed by the commission often saw no significant increase
in pollution even when the water contained thousands of faecal coliform
per 100 millilitres.

Environmentalists condemn the State Pollution Control Commission for
not ensuring that the 1970 Clean Waters Act is implemented properly. Under
these regulations, wastes that are likely to pollute beaches or harm marine
life must not be discharged into ‘ocean outfall waters’. But because the
commission did not classify the locations officially as ‘ocean outfall waters’,
it did not need to press the board to improve sewage treatment and to restrict
the amounts of toxic waste entering the ocean.

The board insists that its Beach Protection Programme, which includes
the deep-water outfalls and monitoring of their performance, some minor
improvements to treatment works and a new policy for the disposal of industrial
waste, is sufficient to end pollution. In March last year, the state government
confirmed that it was not convinced by the board’s assertion; it decided
to seek independent advice and appointed Camp, Dresser and McKee International,
an American engineering firm, to review the programme. Six months later,
the firm completed its review, which the government published immediately.

Camp, Dresser and McKee confirmed that the deep-water outfalls would
not stop the pollution of Sydney’s beaches. It said that winds and currents
would bring sewage plumes, on or below the surface, inshore too quickly
to allow hostile conditions, such as sun and salt, or marine organisms to
rid the ocean of enough pathogens to make the water safe. It said that grease
would still come to the surface and be blown to shore as grease balls, which
protect pathogens within them from degradation. Sydney’s three main outfalls
currently discharge 60 tonnes of grease a day and grease balls are routinely
found on Sydney’s beaches. According to the American firm, ‘contact with,
or direct ingestion of, small grease particles may present an acute public
health hazard’.

The firm recommended a 20-year rehabilitation programme to improve the
city’s sewerage system. The work would cost A$4.4 billion, with more than
half of the sum, around A$2.6 billion, to be spent eliminating sewer overflows.
When it rains, raw sewage and industrial waste overflow into storm water
drains, and from there into Sydney’s waterways. Camp, Dresser and McKee
estimates that almost a third of the suspended solids in the city’s sewage,
or around 45 700 tonnes a year, disappear in this way before the sewage
reaches the treatment works. Camp, Dresser and McKee suggested that overflows
should drain to storage tanks below ground from where tunnels would transfer
them to the treatment works, close to the outfalls.

The firm also estimated that it would cost less than A$1 billion to
add secondary treatment to the sewage works at Malabar and North Head. Secondary
treatment is a biological process that uses naturally occurring microorganisms
to break down sewage; the process creates more solids or sludge for disposal.
Tertiary treatment involves further filtration or more biological decomposition.

The initial response of the state government was that this plan was
far too expensive without federal government help. Then, in December last
year, it announced that it would spend more than A$6 billion over the next
20 years to clean up waterways and beaches in and around Sydney. The plan
includes A$1.9 billion to reduce sewer overflows and A$2.25 billion to improve
sewage treatment. The state government has decided to reject conventional
secondary treatment, which is ‘both expensive and very demanding of land’,
in favour of alternative new technologies . Some of these are advanced forms
of primary treatment that remove 80 to 90 per cent of the solids in the
sewage but do not treat biologically any of the dissolved matter, which
will continue to pollute the environment.

Environmentalists are unhappy that the first stage of the plan, announced
in December and covering the next five years, is modest. The state government
proposes to spend just A$175 million on upgrading sewage treatment at the
three main outfalls. This month, without any public consultation, the Sydney
Water Board is expected to choose between the alternative technologies for
treating sewage that it has been testing. Given the board’s past preference
for the cheapest, rather than the most effective, technologies, environmentalists
remain uneasy that Sydney beaches will be polluted for some time to come.

* * *

Industrial waste swamps Sydney’s civic sewers

EVERY year, industry around Sydney legally discharges more than 150
000 million litres of its waste through the city’s sewers. This is virtually
all of the region’s liquid industrial waste and it makes up nearly half
of the total sewage flow. In 1979, the most recent year for which comprehensive
figures are available, the outfalls discharged about 800 tonnes of heavy
metals into the Pacific Ocean. The waste included about 4 tonnes of mercury
and 16 tonnes of cadmium. Last year, Camp, Dresser and McKee International,
an American engineering firm, estimated that the city’s sewers carry 22
tonnes of organochlorines each year.

In 1988, the Sydney Water Board revised its Trade Waste Policy, the
terms under which it allows waste from industry and commerce to enter the
city’s sewers. Instead of a fixed rate, the board’s charges now reflect
the composition of the waste in terms of the toxic contaminants it contains.
For example, industry can dump cadmium in the sewers for A$1.16 a kilogram
if, for 90 per cent of the time, the metal’s concentration in the effluent
is less than 0.5 milligrams per litre; it costs A$46 a kilogram if the concentration
rises to more than 5 milligrams per litre.

The aim of this sliding scale of charges is to encourage firms to clean
their waste to make it less toxic. But some firms have found easier ways
of saving money. While adding water to the waste to dilute it is technically
illegal, mixing waste streams from different plants and storing them until
concentrations of particular contaminants drop is legitimate.

Various groups of people have attacked the new policy. In February last
year, the Municipal Officers’ Association, a trade union that represents
the interests of inspectors of industrial waste, warned that there are not
enough inspectors to prevent illegal discharges of waste.

Environmentalists argue that a policy based on concentrations of toxic
waste does not protect the environment. According to Richard Gosden of the
campaign, Stop The Ocean Pollution, ‘what matters is total quantities being
discharged each year, since heavy metals and organochlorines accumulate
in the marine environment.’ Gosden maintains that ‘industry should not be
given the choice of paying to put toxic waste into the sewers.’

Camp, Dresser and McKee, which last year reviewed the board’s strategy
for controlling pollution, broadly approved the new policy, which is similar
to others used elsewhere in the world. The firm questioned the prices and
the standards adopted, however. It said that rates would have to be increased
about tenfold before customers could justify the cost of installing their
own treatment works.

Camp, Dresser and McKee also pointed out that the standards of the US
Environmental Protection Agency are much more stringent. The maximum concentration
of heavy metals in trade waste that the EPA allows to enter city sewers
is several times lower than the Sydney Water Board’s standard, which a customer
can exceed if it pays the top rate.

Last December, public pressure forced the board to lower some of these
limits – though they are still much higher than those in the US. The board
also increased its charges for the first time since they were set two years
ago by 16.3 per cent – but this has done little more than match inflation.

* * *

Alternative ways to treat sewage cheaply

THE SYDNEY Water Board is testing three new methods of treating sewage.
The first, invented at the University of New South Wales, Sydney, involves
a polymer filter; the second, from the laboratories of Australia’s research
organisation, CSIRO, uses a magnetic field to draw charged particles from
the effluent. According to their developers, these methods are cheaper and
more efficient than secondary treatment of sewage. The third method, from
a French company, OTV, which is a subsidiary of Companie Generale des Eaux,
Paris, is a biological process that is a form of secondary treatment.

The filter consists of hollow polymer cylinders that are clumped together
to form a tubular membrane through which the effluent flows. According to
its manufacturer, Memtec, the membrane traps particles larger than 0.2 micrometres
across, removing all solids and much of the contamination from greases,
heavy metals and organochlorines. Regular flushing with a high-pressure
gas cleans the membrane and directs the particles to a tank, where they
settle as sludge. The water board has set up a pilot plant to test the filter’s
effectiveness; Memtec claims that because the system is modular it could
easily be used for a large treatment works.

The board has also earmarked A$8.4 million to test the process developed
by CSIRO. An investigation at its Malabar treatment works began earlier
this year. The process involves the addition of magnetically charged iron
oxide particles, or magnetite, to sewage in a sedimentation tank. The slight
positive charge on the magnetite attracts suspended solids. When a magnetic
field passes down the tank, the charged particles, with the sewage attached,
follow it to the bottom of the tank. CSIRO claims that the process removes
between 80 and 90 per cent of solids and that existing treatment tanks can
be easily modified.

The federal government has voiced support for the research, which it
sees as providing opportunities to export Australian technology. Many cities
around the world are looking for cheaper alternatives to conventional secondary
treatment, which is expensive and requires large areas of land for storage
tanks.

The bicarbone process, which is the third method being tested by the
board, occupies one quarter of the land normally required for biological
treatment. Sewage flows through porous gravel that has a high concentration
of microorganisms growing on the surfaces of its grains. Treated effluent
washes the gravel filter periodically. Memtec is also developing a biological
process, based on another type of filter, to work with its polymer membrane.

Environmentalists in Sydney do not want the city authorities to abandon
the notion of secondary treatment. They say that the biological process
offers a natural incentive for the water board to reduce the amount of toxic
waste that industry is allowed to dump in the sewers. They maintain that
if the board did not control the disposal of industrial waste, then the
waste would destroy the natural microorganisms and the treatment process
would break down.

Australian environmentalists look across the Pacific Ocean for support;
secondary treatment is mandatory in the US. Though municipal engineers and
scientists argue that improved primary treatment is sufficient, the US Environmental
Protection Agency is unconvinced.

Sharon Beder, a professional engineer, coordinates environmental education
at the University of Sydney. Her book, Toxic Fish and Sewer Surfing, Allen
& Unwin, 1989, is based on her research on the development of Sydney’s
sewerage system. She also helps to run a campaign to clean up the waters
around Sydney, Stop The Ocean Pollution.

—â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä“
The concentration of organochlorines, in milligrams per kilogram, in three
species of fish found swimming in water around Sydney —â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä“
Species Location Tissue BHC HPTE DDT Dieldrin Total (total)
—â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä“
Red Malabar muscle 1.22 2.60 0.30 0.105 4.23 Morwong
liver 0.16 0.32 – – 0.48 Port muscle 0.01
0.06 0.02 – 0.10 Hacking liver – 0.03 –
– 0.03 Blue Malabar muscle 0.20 0.25 0.02 0.02
0.50 Groper liver 0.08 0.10 – – 0.22
Port muscle – – – – – Hacking liver
– – – – – Rock Malabar muscle –
0.02 – 0.005 0.05 Cale liver – 0.03
– – 0.03 Port muscle – 0.01 – –
0.01 Hacking liver – 0.01 – – 0.01 Maximum
levels 0.01 0.05 1.0 0.1 —â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä“
BHC = Benzen Hexachloride HPTE = Heptachlor Epoxide DDT = Dichloridiphenyltrichloroethane
TOTAL OCs = sum of all organochlorines detected.

—â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä“
SOURCE: Bioaccumulation in Nearshore Organisms l, a 1987 study published
by the State Pollution Control Commission in March 1989. —â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä”â¶Ä“