Sewage Entering Harbour

Harbourcare Submission to Auckland Council Regarding Sewage Treatment Entering Whangateau Harbour

Elizabeth Foster’s submission to Plan Change 64 to District Plan 2000 – Matakana Plan on behalf of the Whangateau Harbourcare Group

Affected Area
Planning Issues
Environmental Impacts
Changing Salinity and Biodiversity
Groundwater Effects
Impacts on the Kahikatea Forest
Impacts on the Golf Course
Toxic Substances
Algal Blooms
Fish Nursery
Significant Wading Bird Area
An Important Shellfish Resource
Overall Estuary Health
Ongoing Risks/Hazards
Long Term Impacts
Loss of Biodiversity and Estuary Health
Sea Level Rise
Human Health
Potential Leakage
Odour and Midges
Other Submissions
Desired Outcomes
Whangateau Harbour

Whangateau Harbour


1. My full name is Elizabeth Ann Foster. Although retired from private practice as a Planner and from the New Zealand Planning Institute, I am currently an active member of the Whangateau Harbourcare Group (WHCG subsequently referred to as Whangateau Harbourcare). I advise them on matters concerning the RMA and act for them in my capacity as a graduate in Environmental Studies from Massey University. I have extensive experience of the RMA and District Plans. I was a member of the Rodney District Council during their Plan’s formulation and for four years acted as the Chairperson of the Hearings Committee and qualified as a professional Commissioner. I recently made a successful presentation to the Auckland Council on behalf of the Whangateau Harbourcare on the content of the Auckland Plan which strongly supports our desire to protect the Whangateau Harbour from inappropriate activities.

2. The Whangateau Harbourcare has been active for 14 years and has a current membership of more than 60 individuals and families. The committee consists of a group of very well informed and well educated people with an intimate knowledge of the area. Of the 10 committee members, 6 are University graduates – 2 with Doctorates, 3 have other tertiary qualifications, and 1 is an experienced Australian conservationist. We also have representatives from the Omaha Beach Community and from Ngati Manuhiri. Details of the activities of the Group can be found on their web site The Whangateau Harbourcare is actively involved in monitoring, educating, planting, pest control and researching to protect what is renowned as the most pristine harbour in Auckland. A Forum under the auspices of the ARC still operates with the intent of developing protective measures to retain the environmental values of the harbour.

3. The reason for this submission is our concern that the planned development and growth of Matakana is entirely dependent on pumping raw sewage to the Jones Road treatment plant in Omaha and the discharge of treated effluent into the Whangateau Harbour (Estuary) catchment. The Councils, their staff and Watercare have refused to take our concerns into consideration and this is the first and only opportunity we have had to properly put our case against the sewage proposals because the ARC decreed that a new Resource Consent was not necessary for the pumping of sewage from Matakana to Jones Road. This means no one concerned about the project has had an effective opportunity to have their say to an independent body.

4. The Whangateau Harbourcare has had a 10 Point Plan for several years which includes Point 8:
“Sewage input to the Jones Road treatment station should be limited to that from the Whangateau catchment.”
The Rodney Local Board has publicly stated that it supports our 10 Point Plan and this was reaffirmed by Board Member Tracey Martin at a function in November this year.

5. The Auckland Plan, which has now been through the full statutory process, states “Our smaller harbours such as Mahurangi and Whangateau, must also be protected to sustain their aesthetic and ecological values.” (5.11-425).
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Affected Area:

6. In spite of The Whangateau Estuary being regularly described as the best and least spoiled estuary in the Auckland City area, the Council proposes to turn this increasingly into a toilet for a wider area outside the catchment. This with no regard for the fact that the estuary and environs are designated as Coastal Protection 1 and 2 and have been identified by the Dept. of Conservation as an Area of Significant Conservation Value.





The Whangateau Catchment is unusually small (fig.1 and fig.2) and fresh water flows are limited. Although described as a harbour there is very little deep water and the area is more correctly described as a shallow estuary from which all but two narrow channels of water depart at low tide. (Brown area in fig.3.)



The estuary is a very important breeding area for a variety of fish species and is the only known significant parore nursery in the Gulf. It is also a regionally renowned source of shellfish which are consumed by people from around the region and is an important feeding ground for many wading and migratory birds.

7. Treated sewage effluent from the Jones Road treatment plant is piped to a eucalyptus plantation on the treatment site and across the causeway to the golf course at Omaha Beach South. In both situations the effluent is distributed through a sub-soil network of pipe lines.

8. All surplus effluent flows into ground water or the upper harbour which is restricted by the causeway and where normal tidal flushing can not occur. The sensitivity of the shallow estuary environment was highlighted by the recent die-off of shellfish when a flush of parasites and disease destroyed 80% of cockles. The basic cause of this die-off has never been properly established and recovery is very slow. A ban on shellfish gathering put in place 3 years ago by MPI Fisheries is being reviewed and continuation of the ban is being recommended by Whangateau Harbourcare with the support of the Local Board.

9. The treatment plant itself is on a site a large portion of which was identified by Tonkin and Taylor as subject to inundation (fig.4) and the whole area of forestry disposal and beyond will ultimately be adversely affected by rising sea levels.



10. Most important is an understanding that treated sewage effluent is not pure water. It contains many substances, suspended or in solution, and on page 33 of AUSTRALIAN GUIDELINES FOR WATER RECYCLING shows a conservative list of substances found in treated sewage from a Queensland plant. Although any substances associated with heavy industry may not be present at Jones Road it can be expected that personal and domestic chemicals will be present in similar quantities. The main issue for concern here is that many of these substances are very stable and will remain in the environment and accumulate to dangerous levels. The RDCs primitive testing of the effluent from Jones Road indicates the presence of Nitrates and Ammonia which are cumulative and faecal coliforms which, while low, indicate the water is not sterile. (Escherischia coli indicate the possible presence of more lethal organisms.) This is the reason Council is unable to allow the effluent to be used on food crops.
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11. From my own experience on the RDC I can vouch for the inadequate provisions made for sewage treatment based on poor engineering advice. The fact that currently the Omaha plant is the only complying plant in Rodney is clearly indicative of the poor planning and management of other facilities. The present Matakana plant, when first installed, had the engineers’ assurance it would last 40 years but it has not even managed 20 years. The quick-fix solution to divert the effluent to another, very sensitive, catchment to avoid polluting the Matakana River is unacceptable

12. The history of the Omaha plant is integral to the current treatment proposals and members of our group have been personally involved since the original development when the Rodney Council’s engineers proposed to pour raw, screened sewage from Omaha Beach directly into the Whangateau estuary. Their intention was to close off the causeway and turn the whole of the upper estuary into a sewage pond. Fortunately the local community voiced strong objections. Dean Grice, a second generation farmer adjacent to the current plant, advised me his father (now deceased) and John Lawrence of Liberty Park led this protest. The developers of the Omaha Beach settlement were then required to construct the Jones Road plant with sufficient capacity for Omaha Beach and Point Wells which would be added at a later date. This meant of course that all the costs were borne by the purchasers of property in the Omaha Beach area.

13. With other members I attended meetings in Auckland with the ARC and developers when the Omaha Plant was being expanded to provide for Omaha South and Point Wells. At one meeting the developer’s engineer stated that he was concerned the plant did not have sufficient capacity to cope and that certain enlargements were necessary. This included the development of further settling ponds. These ponds have never been built. Instead the walls of the existing ponds were raised. At a recent (2011) meeting at the plant we were advised that cracks in this additional wall prevent the full capacity of the ponds being used.

14. The realisation that the Matakana sewage plant would be unable to renew its consents interrupted a Structure Plan for the Omaha and Matakana areas in 2003 and it was replaced by the Matakana Sustainable Development Plan consultation process which began in Nov 2004. As part of this process a survey of residents in the Matakana township area was held, giving options for the disposal of the Matakana sewage. At this time the Council staff had already determined that the sewage should be piped to Jones Road and they gave that as their preferred option. The results of the survey clearly showed that a majority of participants opposed the pumping of Matakana sewage to Omaha.

15. This did not please the Rodney District Council engineers so another survey was held, this time after a “hard sell” by RDC staff about their perceptions of the quality and safety of the Omaha plant option. At this stage there was no investigation that we are aware of into the possible impacts on the harbour environment. By restricting the advertising and misrepresenting the results the RDC was able to show that the survey found in favour of the Omaha option. This was achieved by counting all submissions involving multiple submitters as one submission! The RDC would not accept any criticism of this methodology. For the most part people living in the Whangateau and Ti Point areas were oblivious of this process. This has all resulted in RDC choosing what is undoubtedly a most expensive option. Work done by Waitakere City shows that on-site disposal is the cheapest option.
“Interestingly, this has shown that properly constructed and maintained individual on-site systems are still significantly cheaper for the community as a whole than a community-scale treatment plant or pumping to the urban wastewater network.” (Action Plan 2010)

16. The opportunity is available for an on-site system made locally by a Matakana resident. This system has no liquid effluent disposal field requirement and has been successfully trialled by the previous Waitakere Council. A letter to the Whangateau Residents and Ratepayers Assn in 2010 concerning the Waitakere Wastewater Liaison Group from Penny Hulse (then Deputy Mayor of Waitakere and now of Auckland Council) and Cr Ross Clow states:
“WLG’s flagship innovation is ‘Project Pipi’ constructed for the Huia Hall. It is the first consented zero-energy, zero-discharge, non-odour and low maintenance on-site wastewater system in Auckland and quickly earned the category title of a ‘no-tech’ system. This worm-plant filtration-evaporation system needs no power or pump and has none of the site constraint problems of traditional systems. It also comes at less than half the cost of a hi-tech system. Project Pipi is currently under a consented trial as a new technology demonstration project and has already proven itself under the heavy flow conditions of a popular community hall. It is reliable, flexible, easy to maintain and very cost effective.”

Watercare Sign - Ian Macdonald

An upgraded wastewater system is being installed in Matakana which pipes it all into the Whangateau Harbour catchment – Ian Macdonald

17. The next bombshell dropped on the community by the RDC was that the Matakana connection to the Omaha Plant would proceed before the Point Wells connection thus ignoring the known problems of sewage leaking from septic tanks into the harbour and ignoring the fact that the existing plant was designed only to include Point Wells, a requirement under its consent conditions. A great deal of public protesting eventually resulted in the RDC accepting the obligation to connect Point Wells first. The fact that the RDC considered protecting the Matakana River as more important than the Whangateau estuary remains a point of contention. There are currently no proposals to deal with the problems associated with old septic tanks around the estuary and amazingly connection by Point Wells residents is voluntary while in Matakana it is compulsory.

18. During the consultation process the RDC fudged the issue of land purchases. They claimed this would be costly for a new plant at Matakana while ignoring the cost of purchasing further land for effluent disposal in the Omaha area. This helped them claim the piped sewage option was the cheapest. At the time no acknowledgement was made of the known fact that the Omaha plant is the most expensive in Rodney to operate.

19. When the Whangateau Harbourcare objected as much as we were able to the whole scheme the ARC brought in “experts” to persuade us that our concerns were baseless. A well attended meeting at the Whangateau Hall brought an “expert” presentation on which the whole project was based. This included an explanation of how the effluent sprayed onto the golf course would follow the natural flow of underground water to the open sea in Omaha Bay. Fortunately local engineer Ian Hutchison was present at the meeting and advised the “experts” in no uncertain terms that they were wrong and that the water in fact flows to the estuary. An apology was later received from the “experts” but no explanation was given as to how this should affect the proposal.

20. When Watercare took over control they presented themselves as very willing to communicate with members of the community and listen to their concerns. Subsequently a meeting was arranged in the Whangateau hall at which another “expert”, this time with a degree in Horticulture, gave a detailed report on his trial of increasing effluent disposal to the golf course. He reported that more effluent would be no problem based on one trial in one small area over a couple of months in winter. It was clear he had absolutely no knowledge of either the hydrology of the area nor the underlying geology which completely undermined his argument. In spite of this he went on to make the same presentation to other groups and to the Council. He was unaware that the effluent drains down to a ponding area held back from the harbour by an impermeable “weir” (fig.6)



When there is heavy rain or high tides the accumulated nutrients and toxic chemicals flush in quantity directly into the harbour. This fact is supported by the evidence he had of high levels of ammonia and nitrates at the base of the dunes which he was unable to explain. Attempts to gain adequate answers to a series of questions resulted in references to documents to which we do not have access. This was followed by the cessation of lines of communication by Watercare.

21. Watercare did advise us that there is a serious problem of stormwater intrusion into the existing system from Omaha beach but we have heard nothing to indicate this is being addressed and we can anticipate problems of overflow from the plant in extreme rainfall events. It was also abundantly clear that Watercare had no accurate knowledge of the amount of sewage going to the Omaha Plant. They were unaware, for example, that the sewage from the campground at Whangateau and from septic tank cleaning throughout the wider district is trucked to the Omaha Plant.

22. Also incredible is the Council’s proposal to make the Omaha residents and Point Wells residents pay for the necessary upgrade and connection while the residents of Matakana have been told there will be no costs for their connection because it is an upgrade, not a new system. This, plus the fact that Point Wells connection is voluntary, indicates the determination to give Matakana priority.

23. Requests made in 2011 indicate that Watercare does not hold or have ready access to growth projection information so it is difficult to know how they can justify any actions involving applications for consents for increased treatment or discharge.
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Planning Issues:

24. The Resource Management Act sets a high standard for protection of marine areas and does not anticipate the negative changes which will occur with the discharge of sewage effluent to an enclosed water system.
RMA 2. Purposes and Principles, 6 Matters of National Importance, (a) the preservation of the natural character of the coastal environment (including the coastal marine area), wetlands, and lakes and rivers and their margins, and the protection of them from inappropriate subdivision, use, and development:

25. The proposal is to pump sewage from a Mixed Rural Production and rural village area into a catchment rated Coastal Protection I and II which require a higher level of protection . The Auckland Plan recognises the importance of protection.
Auckland Plan – Chapter 7 Auckland’s Environment, BOX 7.1 environmental principles
Auckland’s environment must be healthy and resilient in order to support life and lifestyles. To ensure this we must recognise that:
1. The environment supports us – the natural resources provided by our environment have limits, and must be protected and restored to ensure our future well-being.
2. We need to consider environmental values in all that we do – the interaction between the environment and people is understood and considered in our everyday behaviour and choices.
3. Everything is connected – human activities affect the air, sea, land and freshwater systems. Understanding the connections between environments in the way we manage them is critical.
4. Biodiversity is everywhere – our flora and fauna, and their habitats, occur on both public and private spaces, and in urban, rural, freshwater and coastal areas. To maintain biodiversity values we must all work together.
5. Natural hazards can affect our well-being – we need to ensure that Auckland and its people are resilient to the effects of natural hazards.
6. We are environmental stewards – future generations will depend on how well we manage the natural environment.

1. This is reinforced by concerns over the degradation of marine environments and in this respect the importance of estuaries as fish nurseries cannot be overstated. The environmental impacts of increasing levels of effluent in the harbour are unacceptable.
433_ Similarly, the Hauraki Gulf State of Environment Report 2011 identified that our marine environment is also under stress. Fish stocks are at low levels and there has been an incremental decline in water quality. The report noted that: ‘it is inevitable that further loss of the Gulf’s natural assets will occur unless bold, sustained and innovative steps are taken to better manage the utilisation of its resources and halt progressive environmental degradation.’
and Our Natural Heritage, Directive 7.4, 441_ Development has resulted in a loss of habitats and a reduction in biodiversity; we must protect and restore habitats and ecosystems. Moves to protect and improve Auckland’s natural heritage have begun.

2. Protecting water is integral to the Auckland Plan and cleaning up the existing problems in the Whangateau harbour must be a priority, not making them worse by increasing contamination.
Directive 7.7, Water quality and demand, 448_ Preserving marine and fresh water quality is fundamental to Auckland’s future. The recreational opportunities water provides are of immense importance to Auckland’s economy and liveability. Many people enjoy beaches, coastlines, lakes, wetlands and streams for swimming, boating, diving, surfing, fishing and other activities. Our water features have significant natural and cultural values, and contribute to our sense of place. However, clean, accessible water is a finite resource. We must know how much we have, and manage its use to safeguard sustainable flow levels in waterways. Any water shortages will affect both urban and rural users, and pose a risk to natural values.

3. The actions of the Council and Watercare are contrary to the requirements of the Plan which recognises the means by which environments are damaged by contaminants and makes preventing this a priority. No endeavour has been made by the Council or Watercare to show that their actions will not have a negative effect on the estuary. The Auckland Plan now states:
459_ Water that runs off the land flows through waterways or pipes to the sea, carrying sediment and contaminants with it. This can degrade or destroy coastal habitats (e.g. by mangrove expansion) and present risks to human health. This is a particular concern for city beaches, which can be unsafe for swimming following heavy rainfall. Continued degradation of the marine habitat will lead to a decline in fish numbers. While we cannot avoid discharges from the land, we can improve water quality and the coastal values of degraded areas. It is important to consider the effects of our land-based activities on the coast

4. It is clear that Watercare is failing to act on the instructions of the Auckland Plan and in continuing to ignore the implications of its actions is acting against the Principles and Policies of the Plan
ADDENDUM, Chapter 7 Auckland’s Environment, Priority 1, Action 9. Ensure the Council undertakes its responsibilities as a landowner in a way that supports and enhances biodiversity.
Action 13. Provide for integrated management within whole catchments, to ensure freshwater and coastal outcomes are met by coordination and sequencing of growth, land use, development and provision of infrastructure.

5. Previously the Rodney District Council did not observe its own requirements by failing to consider the long term impacts of its sewage proposals for the Jones Road facility. They have never endeavoured to provide the community with the evidence that this was safe for the community or for the environment. During the consultation process (March 2007 Presentation for Whangateau Harbourcare) they acknowledged that research needed to be done but we have no knowledge that this has ever occurred. At the same time they acknowledged the possibility of adverse effects.
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Environmental Impacts:

6. None of the issues concerning the outcomes of effluent movement highlighted by the WHCG have been addressed. The movement of this effluent is of vital concern to the health of the estuary and the aquifers beneath it.
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Changing Salinity and Biodiversity:

7. Because of the small size of its catchment there is relatively little fresh water flow to the estuary. The impacts of additional fresh water supplied in the form of effluent to the shallow, saline environment of the estuary has not been considered. Already excess fresh water from the East side of Omaha Beach is being directed to the estuary through sewage and stormwater intrusion. A growing volume of fresh water from developing Matakana will further dilute the system especially as the upper harbour where the effluent is directed has its natural flushing seriously restricted by the causeway. It is in this area that the CPA1 is situated.
American Midland Naturalist The University of Notre Dame
1. Practically all marine animals of bays and estuaries are killed by fresh water.
2. Those which have no method of closing out the fresh water, or which do not live in tubes or burrows are quickly killed by it.

Changing the salinity of the harbour will have a negative impact on the ecology and biodiversity.
8. A further matter for concern is the development of salinity on the discharge sites. The whole principle behind successful land based disposal is that the nutrients and dangerous substances will be taken up and stored for subsequent removal. This is not occurring on either discharge site. Irrigation can have long-term effects on the salinity of soils making them unusable for agriculture. The damaging effects of rising salinity on irrigated soils are well documented and result in reducing yields over time.
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Groundwater Effects:


9. In 2011 a meeting (fig.7) held at the treatment plant heard a scientist advising those present that the trees planted on the disposal area are the wrong species and are incapable of taking sufficient water and nutrients out of the soil. This means, of course, that the excess water percolates through to the aquifer or drains directly to the harbour. The aquifer (B in fig.8) which lies underneath the treatment plant and disposal area is also the aquifer which supplies fresh water to Point Wells and is used in summer to supplement drinking water supplies as well as being used to sustain horticulture.



This aquifer also has some water exchange with the adjacent aquifer shown as C. (Omaha-Leigh Freshwater Resource Allocation/Management Plan – B.D. Bates 1982) Dangerous levels of Nitrogen are inevitable over time and the presence of household chemicals and pharmaceuticals is ignored. These can be tested for in New Zealand now but the Council (and Watercare) consistently refuse to undertake the testing. We believe they do not wish to know what might be found. They would prefer to put off knowledge of the potential damage until some time in the future.
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Impacts on the Kahikatea Forest:

10. The Omaha Taniko Wetlands Scientific Reserve and Kahikatea Forest is a world renowned ecotone which has special recognition and protection as it is unique to New Zealand and has national significance. Effluent used to irrigate the golf course flows through the kahikatea forest to the estuary. Increasing nutrient levels in the forest will have an impact on this ecotone. There will be changes in the nature of the vegetation and possibly the dominance of some species. The containment of nutrients in the upper estuary is also encouraging the development of mangroves. These are threatening the salt marsh which is a significant part of this ecotone.

Upper Whangateau Harbour ecotone with the golf at the top, the kahikatea forest centre and the harbour at low tide at the bottom

Upper Whangateau Harbour ecotone with the golf course at the top, the kahikatea forest centre and the harbour flats at the bottom

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Impacts on the Golf Course:

11. The probability of damage from salination has already been noted. The situation on the golf course is made worse by the fact that the grass is not harvested and removed but is returned to the soil in the form of clippings over the bulk of the course. This means an ongoing build up of nutrients and other substances. Currently the greens are mowed and the grass removed and we see evidence that this is being dumped on the edge of the course to add its nutrient and chemical burden to the lower estuary. Another reported problem is the presence of wet spots where the irrigation builds up and is unable to drain away effectively. This problem will increase with increasing flows from Matakana and will not only damage the turf but also make golfing unpleasant at times.
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Toxic Substances:

12. Regardless of the knowledge that some of the effluent spread through the forest in Jones Road will ultimately end up in the aquifer, only the most basic testing has been done by the Council. In dairying areas the negative impact of effluent on aquifers is well known and of growing concern in the Waikato and Canterbury. The disposal method at Omaha is effectively identical but the effluent contains substances common to sewage systems throughout the world but not found in dairy effluent. The presence of undesirable substances in treated effluent has already been indicated. The importance of these is ignored by the Council and Watercare. There is ample research available on the impact of such substances, especially endocrine disruptors, on fish downstream of sewage plants. A detailed article on the impact of these substances is attached Pharmaceuticals in our water supplies. Are “Drugged Waters” a Water Quality Threat?

13. The failure of the current disposal system to remove undesirable chemicals has already been noted. A study from the University of Western Australia states
“Overall effluent irrigation led to ground-water contamination by N,.P, trace metals and coliform bacteria, which could threaten the long term sustainability of the practice.”
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Algal Blooms:

14. During summer months there is growing evidence of algal blooms in the estuary as observed by Dr Roger Grace and residents of Omaha Beach. These blooms are generally associated with increased nutrient levels in the water and can have a devastating effect on the estuary’s natural community.
ARC Whangateau Harbour and Catchment Study 2009
… an upward trend in phosphorus and chlorophyll a was detected at the ARC’s Ti Point water quality monitoring site between 1991 and 2007 (Scarsbrook 2008).

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Fish Nursery:

15. As stated previously this is an important fish nursery. Research by Fisheries ecologist Mark Morrison shows that virtually all the parore from Pakiri to Kawau come from Whangateau. Beds of necklace weed on two sandstone reefs near the island and South of the causeway (where the effluent is concentrated) are important habitats for the parore as the tide recedes. “Clearly the channel behind Horseshoe Island is also a nursery area for snapper, trevally, kahawai and spotty, and the mangroves nearby are nurseries for yellow eye mullet and probably grey mullet. Sewage seeping into the Whangateau south of the causeway (ie. from ground water near Jones Road and the golf course) could eventually interfere with the nursery area on the sandstone reef south of the causeway. With Matakana’s sewage about to come over the hill, and new subdivisions coming on stream in Matakana, the situation can only get worse.” (Dr Roger Grace)
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Significant Wading Bird Area:

16. The estuary is a significant area of food sources for wading birds and is noted for the presence of rare New Zealand dotterels. Large flocks of migratory birds such as godwits rely on the estuary for food to sustain them on their long flights. Changes to the composition of this food source and its destruction by an influx of fresh water and an overgrowth of mangroves encouraged by high nutrient levels may result in loss of this habitat and a loss to the birds, the human community and to tourism. The influx of mangroves South of the causeway is a serious threat to the wading birds and their feeding area. As silt is not a serious problem in this area of the estuary it can be assumed that the mangroves are attracted by high nutrient levels.

Young mangroves in the Whangateau Harbour

Young mangroves in the Whangateau Harbour

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An Important Shellfish Resource:

17. The Whangateau Estuary is the only significant shellfish resource remaining in the Auckland region. The die-off in 2009 was a strong indicator that all is not well in the estuary and sadly recent counts show little sign of recovery. (fig.10)



“… as a result of the crash by March 2009 we had lost 82.2% of cockles over 30mm when compared to the November 2008 results. By November 2010 it was a little worse with 86.1% loss compared to 2008, and by November 2011 the numbers were still 81.7% down on the pre-crash numbers. So no indication of recovery yet.
I have attached a second analysis of our data… looking at mean density of cockles for all our samples. The lower graph is the more telling one showing the larger cockles have dropped to around 100 per square metre and pretty well stayed there since the crash.”
(Dr Roger Grace)
These shellfish are filter feeders which sift through the contents of the harbour, both good and bad. Their presence is the reason for the water’s clarity and any contamination makes them a dangerous food source. It is inconceivable that any estuary which already has problems of contamination should be asked to have its burden increased.
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Overall Estuary Health:

18. The action of filter feeding, death and sedimentation will result in a gradual build up of chemicals from sewage in the sediment of the estuary floor. A recent conversation with a tradesman revealed that he had helped a friend take a boat out of the water near Omaha Beach. This boat had been moored for some time and they were cleaning the bottom which had some very large mussels attached. These were taken home and steamed but the sewage smell was so bad they had to be thrown out. All indications are that the health of the estuary is declining.
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Ongoing Risks/Hazards:

19. Highly localised heavy rainfall events occur regularly in this area. An event of this nature in the vicinity of the ponds could result in serious effluent overflows draining directly through open drains to the estuary. As it is very shallow water there would be little dilution until a tide change with an inevitable impact on the estuary life. We have already referred to the issue of stormwater intrusion as described by Watercare and combined with inadequate storage capacity any increase in effluent load at the plant will increase the risks.
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Long Term Impacts:

20. The impacts of a chemical buildup in the estuary may take many years to repair even if action is taken now. Nitrogen is known to filter through soil to an aquifer over a period of at least 20 years and a further 20 years plus after removal of the contaminating source is necessary to restore the water to normal. Many of the pharmaceuticals are very stable and resist degradation so can remain active in soils and water for an unknown period of time.
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Loss of Biodiversity and Estuary Health:

21. Changes to the estuary environment will result in loss of the current biodiversity and change to dominant species which thrive in a polluted environment. The fine balance which has existed over millennia will be lost and the residents of the estuary irrevocably changed. The development of mangroves in particular will result in a complete change in the nature and biodiversity of the estuary.
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Sea Level Rise:

22. The inevitable and inexorable rise of the sea will result in a shortened life for the treatment plant and loss of the areas which are currently used for disposal. The plant itself will always be at risk from tsunamis and extreme high tide events. Plans should already be underway to replace the plant with an alternative on a much more sustainable site. This need, particularly for Matakana, is only a matter of time. The Omaha Beach and Point Wells settlements will no longer be viable some time in the not-so-distant future.
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Human Health:

23. The potential issue of risk to human health is not being considered as plans for the expansion of the treatment plant are pursued We have already established that the sewage effluent is not pure. The risks to people drinking water from the aquifer below the disposal areas are not considered nor is the risk from water based activities in the estuary and in particular the possibility of eating contaminated sea food.
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24. There is ongoing potential for leaks of raw sewage from ageing or damaged pipes. The hilly land in this area is extremely unstable and subject to serious slips after heavy rain events. A bad slip on the hill between Matakana and Omaha during Cyclone Bola is testament to this and underlines the threat to the sewage pipeline. If there is any damage to the pipe returning effluent to the golf course there is not sufficient capacity in the eucalypts to take the excess. In short there are no provisions for such emergencies.
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Odour and Midges:

25. Existing problems with odour and midges will undoubtedly increase with expansion of the treatment plant.
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Other Submissions:

26. We support the concept of Watercare’s submission to restrict the size of Matakana only in terms of effluent discharge. We do not oppose the development as such if they are prepared to deal with their own sewage in their own catchment, but if this hearing supports the proposal to pump sewage to the Whangateau estuary we believe that restriction of the Matakana population is crucial until such time as sustainable treatment of their sewage is provided for.
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27. It is apparent that, far from being pristine, the Whangateau estuary already has serious problems and yet the provision of disposal from Matakana is taking precedence over the health of the estuary so that development can occur in the Matakana settlement.

28. The volume of sewage will grow steadily as Matakana is developed and Omaha Beach becomes settled by permanent residents. A high proportion of the people in the area will be retired and it is known that this group consumes the highest volume of pharmaceuticals.

29. It is also apparent that neither the Council nor Watercare are concerned about the potential impact on the estuary or the views of residents in the area. They are not prepared to do the necessary research in what is a comparatively new science and they already have plans for expansion of the existing Jones Road plant to accommodate a growing population elsewhere. It is clear from the manner in which the Council has dealt with the Point Wells and Matakana treatment issues that they are endeavouring to find room for Matakana in a plant without adequate capacity by discouraging Point Wells residents from connecting and thus to put off the need to purchase further land for disposal.

30. The people in the harbour catchment have not been widely or adequately consulted about their views on whether they wish the transfer of sewage to occur. If there has been any research on any of these issues we have not been given access to it.
“There is little data available on the concentrations of EDCs present in the local environment and therefore monitoring of EDCs in effluent discharges and in receiving environments is necessary in order to assess the risk that these compounds pose to New Zealand’s environment and communities.”
(ARC Publication Executive Summary – fig.11)



31. The whole development of the Jones Road plant and disposal of the effluent has been an extraordinary experiment based on no known science. To continue this experiment and to enlarge it is morally and environmentally wrong. The Conclusions from the ARC 2009 Forum study (TR009/003,4,5,6 available on-line and apparently disregarded by Council) make a clear statement:
Whangateau Harbour is arguably the Auckland region’s most valuable mainland estuary. Unfortunately the natural values of the harbour are being degraded by the cumulative impacts of numerous activities that are carried out in the coastal marine area and in the adjoining catchment. Further degradation is inevitable if preventative and, in some cases, remedial action is not taken.
Management actions should be underpinned by clearly defined objectives for the environmental management of the harbour’s resources. These objectives need to take into account the special ecological, conservation, natural character and landscape functions and values of the harbour. It is recommended that these objectives form the basis for developing an integrated strategy that address the cumulative effects of existing activities, plus those related to future population growth, changing land use, and catchment and coastal development.

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Desired Outcomes:

32. We consider a halt to the plans to transfer Matakana sewage to Omaha is the only acceptable option if the Auckland Plan is to be meaningful and if the degradation of the estuary is to be reversed. The Commissioners should then prevent any further development in Matakana until a suitable alternative is found in their own catchment.

33. If the Council and Watercare persist in pumping raw sewage to Jones Road there is an opportunity at this hearing for the Commissioners to allow the development of Matakana only if the Council pumps Matakana’s treated effluent back to Matakana to be distributed in some suitable area in their own catchment. We understand that this can be done using the present pipeline This would have a good outcome by making the residents of Matakana responsible for their own discharges to their own catchment. However this would not alleviate the high risk elements in this process.

Elizabeth Foster BA (Env.St.)
for Whangateau HarbourCare Group (Inc)

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  1. This is a really good and in-depth discussion of the issues of sewage release to the catchment of the Whangateau Harbour. It should be mandatory “bed-time reading” for all Auckland City Councillors, and Council staff involved with water quality issues. Thanks to Elizabeth Foster for her untiring efforts to protect the Whangateau Harbour from increasing impacts from sewage release.

  2. Danny Liufalani says:

    I have recently read about Elizabeth Fosters work for the region and the report has said it all..I just wonder whether ACC ever took noticed of this report or they are pushing for the Unitary plan to set in of which everything will changed again.I am concerned being a resident in Jones Road.. and I have the solution to solve all this,only problem is ACC/Wastercare has got the monopoly…..

  3. all to the death ears of the Council…..How New Zealand Failed in the enviroment issues……..we had water water proplem in the past ..luckly our water was from the watersupply tanks..

  4. Danny Liufalani says:

    We have successfully demonstrated dewatering process with Watercare I would be keen to share our interest. My family live at Jones Road sinced 1987

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