Getting into Deep Water: Sydney's Extended Ocean Sewage Outfalls
Citation: Sharon Beder, 'Getting into Deep Water: Sydney's Extended Ocean Sewage Outfalls' in Pam Scott, ed., A Herd of White Elephants: Australia's Science & Technology Policy, Hale and Iremonger, Sydney, 1992, pp62-74.
This is a final version submitted for publication.
In the 1960s the Sydney Water Board and its engineering consultants devised a scheme to avoid fully treating the sewage going into the ocean. They proposed that instead of installing secondary treatment at the three main ocean outfalls in Sydney, they would leave the sewage only partly treated and discharge it into deep water 2-4 kilometres offshore. There were two main reasons for deciding on this course of action. One was that secondary treatment was expensive and required a lot of land. The second reason was to avoid having to clamp down on toxic waste being allowed into the sewers. Toxic waste would have interfered with the secondary treatment process.
Now more than twenty years later, as the extended outfalls are completed and commissioned at a cost of some $300 million, the government has promised to upgrade the coastal treatment plants so that sewage will be treated to at least secondary treatment standards before discharge into the ocean. Also the Water Board is being forced to restrict toxic waste going into the sewers anyway because of the contamination of fish in Sydney coastal waters that is occurring.
The deepwater outfalls, which were supposed to avoid both these decisions, have merely delayed them at a substantial cost to the people of Sydney. This chapter will consider the decision-making process that lead to the establishment of these deepwater white elephants and examine the reasons why it was not realized much sooner that they would not eliminate the need for secondary treatment and stricter toxic waste control.
The Attraction of Deepwater Outfalls
The concept of extended deepwater sewage outfalls dates back to the nineteenth century. As early as 1876, the Sydney and Suburban Sewage and Health Board recommended that some Sydney Harbour outfalls be extended into deeper water. It argued,
The idea of promoting deepwater outfalls as being a means of treatment rather than merely a method of disposal was advanced earlier this century by an American, A.M.Rawn, who investigated a number of outfalls on the Californian coast. Rawn was particularly excited at the prospect of utilising the ocean as a free means of treatment.
In 1959 the Metropolitan Water Sewerage and Drainage Board (now the Water Board) drew up a long-term plan for dealing with the Sydney sewage which was piped into the sea at Bondi and Malabar (see accompanying map). It proposed that primary treatment plants be built and that at some time in the future either secondary treatment or a deepwater outfall would have to be installed. These plans were reviewed in 1965 by the US engineering firm Brown and Caldwell which recommended that deepwater outfalls be installed rather than secondary treatment.
At the time there were no standards for bathing water quality and wastes being discharged into the ocean were not regulated. The NSW government authorities did not view sewage pollution as a health problem but rather as an aesthetic problem despite the regular complaints from beachgoers that they got infections and illnesses from swimming at Sydney's beaches.
In 1970 a Water Board spokesman was reported in the media as saying that the primary treatment works being constructed at the time at Malabar would remove pollution from the beaches and all that would remain of the pollution would be a harmless stain. The only way to remove this brown stain, the Board spokesman said, in anticipation of the future plans, would be to install outfalls to carry the discharge several miles out to sea.
In March 1971 the Water Board instructed the consultant engineering firm, Caldwell Connell Engineers P/L, to do a feasibility study into the construction of deepwater outfalls for the three main Sydney outfalls at North Head, Malabar and Bondi. Caldwell Connell was an amalgamation of the US firm of Brown and Caldwell, which had already recommended the deepwater outfalls, and the Australian firm of John Connell, Mott Hay & Anderson.
Caldwell Connell presented its 288 page report in 1976 following investigations costing around one million dollars. It dismissed the alternatives to deepwater outfalls in one paragraph at the beginning of their report which included the statement:
Given the layout of the existing system the choice, it claimed, was between providing a high degree of treatment (secondary treatment) with minimum ocean outfall facilities or a low degree of treatment with deepwater outfalls. It dismissed the secondary treatment option because it said there was not enough readily available land, and it only considered the deepwater outfall alternative in its study.
Another reason for not choosing to install secondary treatment, even though it was not stated publicly at the time, was the desire of the government and the Water Board to service industry by allowing them to use the sewers as a cheap toxic waste disposal outlet. Secondary treatment is a biological process which utilizes naturally occurring micro-organisms to break down and treat the sewage (in much the same way as food scraps decompose in a compost heap). Toxic waste can kill these organisms and upset the whole process. The installation of secondary treatment would have necessitated much tighter restrictions on the discharge of industrial waste. A 1970 Water Board Trade Waste Committee report described how the volume and significance of industrial wastes had increased over the years till industrial wastes in 1970 "largely determined" the characteristics of the raw sewage at the main outfalls. 
What the Deepwater Outfalls were Supposed to Achieve
The deepwater outfalls were to avoid the need for secondary treatment by hiding the sewage field from view and allowing the ocean to treat the sewage. The outfalls would consist of a tunnel under the sea floor extending between 2 and 4 kilometres out to sea. For the last 800m or so of the tunnel there would be pipes rising up from the tunnel and taking the sewage to diffusers sitting on the sea floor. These diffusers would spray the sewage out (somewhat like a shower head does) and in so doing provide extra dilution to the sewage enabling it to mix with the cold layers of water at the bottom of the ocean (as shown in the diagram).
The combined effect of the diffusers, the depth and the mixing with the cold seawater was designed to ensure that the sewage field seldom came to the surface of the ocean but remained submerged in deeper water. The State Pollution Control Commission, which was set up in 1972, was particularly concerned about the visibility of surface sewage fields. They wanted to know at what dilution the surface field would cease to be visible to a layperson from the shore, a boat and an aircraft, and under what circumstances would surface slicks of floatable material become visible.
Their concern stemmed from field studies in California where slicks of floatable material were visible above the deepwater outfall diffusers off Los Angeles even though the effluent discharging from those outfalls was better treated than the effluent which would be discharged at Malabar.
Caldwell Connell assured the Commission that the Malabar sewage field would generally not be visible from the shore, boat, or air, and that on the rare occasion when there was a malfunction, illegal or uncontrolled discharge or a rare combination of climatic conditions such as no current, wind or waves, only a person with keen eyesight would be able to see it.
Although visual indicators were a key concern of the Commission, the Water Board was also concerned that the new outfalls would have to comply with Clean Waters Regulations, established in 1972, which required that wastes should only be discharged if they would "not adversely affect beaches" and were "visually free from grease, oil and solids and free from settleable matter". Moreover, wastes were not to be discharged if the resulting concentration of the wastes in the waters:
To avoid having to meet these regulations, the Water Board requested that the State Pollution Control Commission (SPCC) formulate standards in terms of specific volumes and concentrations rather than end goals which the deepwater outfalls would have to meet. As a result, the document ñDesign Criteria for Ocean Dischargeî was put together in consultation with the Board's engineers and published in 1974. In this document bathing water standards were laid down in terms of concentrations of faecal coliform and water quality standards were laid down in terms of concentrations of toxic wastes. (Faecal coliform are organisms that occur naturally in the human gut and are used as an indicator of the presence of sewage.)
Because the standards were in terms of concentrations of pathogens and toxins in the receiving waters rather than in the effluent, they were well suited to a solution that facilitated dilution in the ocean rather than treatment before discharge. Such standards, which were supposed to be an interpretation of the Clean Waters Regulations, did not protect beaches nor the marine life from adverse effects. Yet the Water Board could be confident that their deepwater outfalls would meet SPCC standards.
The Reasons Secondary Treatment is Still Necessary
Turning the ocean into a secondary treatment plant becomes a problem if people want to swim in it because of the presence of disease-causing viruses and bacteria. Yet this problem was explained away by the Board's consultants. Caldwell Connell stated in its 1976 report that reduction of organisms such as bacteria and viruses would occur mainly because of the dilution, but they would also die in the hostile seawater environment, be consumed by protozoans and other small animals, and be reduced due to sedimentation, adsorption, normal biological mortality and sunlight.
Caldwell Connell only studied the die off rates of faecal coliform although it admitted that there was very little evidence that related "faecal coliform concentration to the incidence of water borne disease", and that different organisms, including those of sewage origin, could be expected to have different die-off rates. However, it defended the use of faecal coliforms as an indicator of pollution of sewage origin because it was not 'practicable' to routinely monitor pathogenic organisms directly.
It found that ninety per cent of faecal coliform die off in 1 to 7 hours during the daytime. Viruses, Caldwell Connell said, were difficult and costly to test for, so they were not investigated at all. The possibility of viruses surviving for long periods was dismissed with a statement that "viruses can only multiply in living host cells" and their numbers "diminish rapidly through treatment, dilution and natural die-off."
Such conclusions don't seem to be supported in the scientific literature which shows that viruses and other bacteria live much longer than faecal coliform. The extra distance the sewage has to travel to shore from the deepwater outfalls (2-4kms) only adds a few hours, if that, to the travel time of the sewage field; long enough to kill faecal coliform but not viruses. It seems Caldwell Connell's primary concern was not with ensuring that the deepwater outfalls posed no health threat to bathers but rather that the new outfalls would comply with the faecal coliform bathing water standards set by the SPCC.
The Australian Atomic Energy Commission (AAEC) has shown that dilution and dispersal of sewage in the ocean does not protect bathers from sewage-based infections either. Between 1976 and 1981 an AAEC team carried out work for the Water Board to study the processes of ocean dispersion of sewage. Using a radioisotope, gold-198, they labelled sewage solids before discharge into the ocean and then monitored their progress.
The study found that grease was extremely persistent in the ocean and did not dilute much as far as 5km from the discharge point and could even concentrate so that seven days later the tracer would still be found in the same concentration as at the beginning. They noted, in particular, that wax or grease could interfere with the dispersion and purification of bacteria which could be adsorbed into particulate matter and survive in grease accumulations where predators could not get to them, nor could the oxygen nor sunlight. There was, for this reason, a strong correlation between the grease content of beach sands and the bacteria count in adjacent waters, and therefore the presence of grease was not just an aesthetic problem but also indicated a health problem.
In this way, bacteria and viruses could be carried to remote locations where the concentration of bacterial predators would be low and the die off rate much lower. For this reason, they suggested the deepwater outfalls might have little benefit and might even have the added disadvantage that:
A single sewage particle can contain a large dose of microorganisms because of the tendency for particles to attract viruses and bacteria on their surfaces. This is another reason why the dilution mechanism is not adequate for dealing with water-borne disease. As has been pointed out by microbiologists:
Furthermore, viruses can live for months in seawater and build up over time. Already, in the United States, the authorities fear that routine discharge of sewage effluent and the dumping of sewage sludge are introducing large numbers of viable microorganisms, including pathogens, into the coastal waters and oceans and that their densities in both the water and the sediments may be increasing.
Why Toxic Waste Will Still Need to be Reduced
Another problem with treating the ocean as a secondary treatment plant is that toxic wastes pose a threat both to the marine environment and also to seafood consumers. Toxic wastes can be taken up by marine vegetation and organisms and accumulated. Organic chemicals, such as those in the organochlorine group, are very stable and often persist in the environment for long periods. Marine animals can accumulate these compounds even when there are very low concentrations of the compounds in the water around them. Similarly other toxic materials, in particular, trace metals, can be taken up and accumulated by aquatic organisms. Sydney's coastal waters, into which the three main ocean outfalls discharge, support fish and other marine life that are fished both commercially and for recreation.
The Water Board and its consultants always denied that toxic wastes from the outfalls would accumulate in marine life because they had found no evidence that such wastes had accumulated in the sea floor sediments around the outfalls. As evidence came to hand that fish were in fact contaminated by toxic waste, they covered up that evidence and maintained their stance.
An ex-Water Board employee, Ron Snape, a marine biologist, told the press in 1989 that whilst he was conducting a survey of marine life off Sydney's outfalls for the Board in the early 70s, he carried out tests for concentrations of heavy metals and organochlorines although this was not part of his brief. He claims that he found concentrations of mercury, zinc, cadmium and dieldrin in the samples caught near the Malabar outfall, and the Blackfish had concentrations of mercury up to six times maximum safety levels for seafood. He says the Water Board did not want to know, and he was forced to resign over it. He was coaxed back into their employment and completed the report in 1975, but claims that the report was heavily rewritten and distorted.
The results of this study which was carried out in 1973 were not published for a number of years. Heavy metals and/or pesticides were accumulating in nearly every species sampled, and out of 18 organisms (including fish and mussels) taken near the outfalls, more than half (10) were so contaminated that they were above maximum limits set by the National Health and Medical Research Council (NH&MRC) for seafood. In a confidential 1973 report, Caldwell Connell reported that:
Caldwell Connell went on to complete and publish its million dollar feasibility study into the extended ocean outfalls which did not mention the 1973 findings. It stated in its report that a detailed investigation of levels of pesticides and heavy metals in the marine environment was beyond their scope. When the 1973 findings were published in part in the Environmental Impact Studies in 1979, the Water Board actually stated that:
This sort of statement in an Environmental Impact Statement is misleading at the very least, given the concern of those involved with the survey. At least two other studies of contamination of fish undertaken by the Fisheries Research Institute of fish in the vicinity of the ocean outfall sites were not mentioned in the Environmental Impact Statements nor were they published elsewhere. In one study, seven out of eight blue groper sampled from Manly waters were above the NH&MRC maximum allowable levels for mercury, and one red morwong out of eight was also over.
The second study by the Fisheries Research Institute was also kept secret for years. Blue groper and red morwong were collected between 1977 and 1979 near the ocean outfalls and tested for pesticides. Three of forty blue groper specimens exceeded NH&MRC maximum levels for dieldrin. Ten of 58 red morwong exceeded the same levels for dieldrin and five had DDT body burdens in excess of NH&MRC maximum levels for total DDT. At least one of the red morwong had DDT levels that were 64 times the NH&MRC maximum levels, and one had levels of dieldrin at 13 times the maximum levels. PCB's (Polychlorinated Biphenyls) were also detected in high levels.
By the end of the 1970s, at least five government bodies knew that toxic industrial waste was accumulating in marine life near Sydney's outfalls; the Water Board, the Fisheries Research Institute, the Health Commission (which had carried out the analysis of Fisheries Research Institute fish), the Australian Museum and the SPCC. Yet none of these bodies and none of their employees chose to make public that knowledge and only the Australian Museum expressed any concern about this problem when the Environmental Impact Statements were published.
The submissions on the Environmental Impact Statements from the government departments and councils were generally in support of the deepwater outfalls, whilst the submissions from environmental groups and members of the public were generally opposed to them. However, because the opposition was mainly to ocean outfalls in principle and because it was not supported by a wealth of scientific evidence that the outfalls would not achieve their purpose, opponents were easily dismissed and a few years later, in 1983 and 1984, the approval to go ahead with the deepwater outfalls was granted by the SPCC and construction began.
In a 1987 bioaccumulation study commissioned by the SPCC, three fish species were tested. Two, the red morwong and the blue groper were found to have average levels of organochlorines in their muscle tissue well above NH&MRC limits. The eight red morwong taken at Malabar, in fact, had average levels of benzene hexachloride (BHC) over 120 times the NH&MRC maximum levels, average levels of heptachlor epoxide over 50 times the levels, and average levels of dieldrin just over the NH&MRC limits.
The SPCC commissioned a second bioaccumulation study in 1988 which tested red morwong at a variety of sites along the Sydney coastline. The second study confirmed that the contamination of fish was from the sewage outfalls and it again found high levels of organochlorines, including average levels of chlordane 12 times the NH&MRC limits and hexachlorobenzene (HCB) at 3 times the limits up to 3.5 km from the Malabar outfall. Fish at all sites had levels of mercury above the limits, and some also had levels of DDT and Deildrin above the limits.
The Power of Adverse Publicity
Despite the alarming levels of organochlorines found in fish caught off the Sydney coast nothing was done and no one was told. It was only in 1989, when these results were leaked to the Sydney Morning Herald, that the problem of toxic waste going into the ocean was officially recognized and moves made to restrict toxic waste being allowed into the sewers.
At this time the Water Board, under media questioning, admitted that it did not know how much toxic waste it was discharging into the ocean and had not been properly monitoring its discharges. It promised to institute a monitoring programme and to cease by 1992 its practice of dumping sewage sludge (the residue from sewage treatment) into the ocean. It also promised to reduce the amount of toxic waste getting into the sewers and to increase the number of inspectors policing industrial dischargers.
Until this time, the annual licences which the SPCC granted to the Water Board to allow it to put the sewage into the sea contained no limits on the amount of toxic waste that could be in the sewage. In May 1989 the SPCC finally placed limits on five toxic substances in Water Board licences. These were five of toxic substances that had been shown to be accumulating in fish above NH&MRC limits in the 1987 and 1988 bioaccumulation studies. Limits for dieldrin are under consideration at the moment.
The revelations of secrecy and deception, and some might say incompetence, that appeared in the media at this time damaged the Water Board's credibility and caused the media to review their uncritical acceptance of the Water Board's line on the deepwater outfalls and how they would clean up the beaches once and for all. Old reports, dissident experts and environmentalists were hauled out of the cupboards to restate their criticisms of the deepwater outfalls. The State government was forced to bring in outside experts to review and assess the Water Board's plans.
Camp, Dresser & McKee, a US based firm, was commissioned to carry out the review. It confirmed in September, 1989 that the deepwater outfalls would not relieve Sydney's coastline of sewage pollution as had been predicted by the Water Board and its consultants. It recommended a $4 billion suite of improvements to be implemented over 20 years, including the upgrading of treatment at Sydney's ocean outfalls and the prevention of sewer overflows. The NSW government went one step further and promised more than $6 billion dollars worth of improvements to the sewerage system, including sewage treatment to at least secondary treatment standards.
The deepwater outfalls are expensive white elephants because they were built to avoid installing secondary treatment plants and to allow industry to continue using the sewers as a cheap toxic waste disposal service and they will not achieve either of these goals.
It is now well recognized that it is not satisfactory to relegate secondary treatment to the end of a pipe in the ocean because of the presence of disease causing organisms in the sewage which pose a threat to people who use the ocean for other purposes such as bathing. Sewage must be adequately treated before it is discharged whether or not it is comes to the surface of the ocean and is obvious to see. The government now admits that ñout of sight should not be out of mindî.
It is also now widely recognized that dumping toxic waste into the ocean is undesirable from a public health and environmental point of view. The costs of past policies that have facilitated the wholesale dumping of toxic waste into the Sydney sewers have recently become painfully obvious. Fish have become contaminated and this has cost the fishing industry millions of dollars in lost sales as people have become suspicious of fish they buy in the markets even though only a small percentage of them come from Sydney waters.
The decision in the 1960s not to install secondary treatment has been an expensive one for other reasons as well. Had the decision gone the other way, we would now have secondary treatment at the main ocean outfalls in Sydney and this would have forced the Board to cutback on toxic waste permitted into the sewers. The secondary treatment itself would be removing a far higher percentage of toxic waste from the effluent than is the case now. Instead, we are now once again facing the prospect of installing secondary treatment, and it seems even more out of reach now than it did in 1959 because of escalating real estate prices and inflation. In the meantime, the deepwater outfalls are beginning to take the city's load of toxic waste and dumping it closer to commercial fishing areas in deep water.
There has been a failure of the Water Board, successive governments and their engineering and scientific advisers to recognize the health effects of swimming in sewage polluted water. Even as evidence of these problems came to hand, it was ignored, and they pressed ahead with their plans, going to great lengths to convince the community that they had everything under control and that their cheap alternative to secondary treatment would work miracles.
It was assumed that the public would not be willing to pay for secondary treatment. But it is too easy to assume the community will not pay the price of environmental protection when they are not asked the question, and are not informed of the likely outcomes of their answers. Following publicity about the problems associated with sewage polluted waters and the doubts about whether the deepwater outfalls would work, polls showed that Sydney people were in fact willing to pay higher rates if it meant cleaner beaches. The Water Board was able to impose an $80 annual environmental levy on each household on top of their normal rates.
Legislation could also have played a key role in preventing these events. The Clean Waters Act and Regulations spelt out clearly and unambiguously what was required. Wastes were not to be discharged that would adversely affect beaches or be likely to accumulate in marine life. Had this legislation been properly implemented, then the need for secondary treatment and restriction of toxic waste going into the sewers would have been recognized fifteen years earlier. Yet those legislated requirements were supplanted by a set of guidelines which resulted from negotiations between the SPCC and the Water Board, without any community input whatsoever. The resulting standards were designed so they could easily be met by the proposed deepwater outfalls.
The need to restrict toxic waste going into the sewers was also disguised by governmental and bureaucratic secrecy. Studies from 1973 through to 1987 showed that toxic waste was accumulating in marine life but little was done about it during that time. It was only when the results of some of these studies were finally leaked to the media that the community was able to exert pressure on the government to reduce toxic waste going from industry, via the sewers, into the marine environment.
The original decision to allow industry to continue using the sewers as a cheap toxic waste dump, and to substitute deepwater outfalls for proper secondary treatment illustrates some of the aspects of political decision making which Paul Couchman outlines in the first chapter. Although it was public complaints about beach pollution which prompted the necessity for political action, the problem was defined as being how to do something to diminish the complaints without the need to install secondary treatment and cut back on toxic waste going into the sewers. By defining the problem in this way the actual problems of beach and marine pollution were not directly addressed and it is not really surprising that they have not been solved.
The main reason why the problem was defined in this way was to please business interests and reflects the privileged position business leaders have in policy making. The inability of the government and the Water Board to take a tough stance towards industrial waste going into the sewers is a measure of the influence of those industries that use the sewers as a cheap disposal service.
This influence of business leaders has been magnified by the lack of access of other groups in the community to the decision-making process. The government authorities were able to define the problem in the way they did because it never came under full public discussion. In the early stages the public was not consulted and in the later stages too much information was withheld and kept secret for public debate to be meaningful.
Professor Sharon Beder is a visiting professorial fellow at the University of Wollongong.
Sharon Beder's Publications can be found at http://www.uow.edu.au/~sharonb