Western water supply strategy–
Huia Water Treatment Plant
replacement
Response to questions from the public.
Please note that we are continuing to review the feedback and will update the following information.
Last update: 6 April 2017
Introduction
There are three potential sites for the replacement plant for
the Huia Water Treatment Plant, one of which is in Parker
Road (two sub-sites).
There is no duty on applicants such as Watercare to consult
over applications under the Resource Management Act
1991. However, Watercare always wishes to work with the
communities in which its facilities are located and follows an
extensive process of consultation.
That process in recent years has seen Watercare receive
resource consent for large projects such as the Central
Interceptor, the Pukekohe East reservoirs, the Hunua 4
Watermain, the North Harbour 2 Watermain, and the Army
Bay outfall. All of these projects are significant in size,
scope and cost and only one has required a hearing before
the Environment Court. In part, that is due to the extensive
consultation process undertaken for each project.
The same process has been applied to the proposed
replacement for the ageing Huia Water Treatment Plant.
The consultation process commenced at a high level with
organisations such as the Local Board, the Department of
Conservation, and the Waitakere Ranges Protection Society
before any specific sites were identified.
The advisers to Watercare initially identified around forty
possible sites, these were narrowed to twenty-one sites, then
to eight and now down to three.
Details of these sites are set out in several technical reports
which are available on the Watercare website. http://www.watercare.co.nz/about-watercare/news/Pages/
Huia-water-treatment-plant-replacement.aspx
The consultation process intensifies as the possible sites are
reduced in number which resulted in the meeting at Oratia on
the evening of Tuesday 21 February in respect to the Parker
Road sites, and at Titirangi on the evening of Wednesday
22 February 2017 in respect to the current site of the Huia
Water Treatment Plant and the Manuka Road Site.
Further open days are planned for 8 and 9 April 2017 at the
Huia Water Treatment Plant.
Watercare has owned the sites at Woodland Road and
at Manuka Road for some years and in November 2016
Watercare purchased the site at 130 Parker Road on the
open market.
Some forty letters were delivered in November 2016 to
the owners of neighbouring properties, the Local Board
and Local Councillors, advising that the property had been
purchased as an option for the replacement Huia plant.
There is no legal requirement for Watercare to have done
that but Watercare wanted to be transparent and ethical in
advising members of the public who might be affected, in
the event the site in Parker Road was finally selected.
Once the final site has been determined then specific
layouts for the plant would be developed. There would be
plans showing height, distance from boundary, landscaping
proposals and other details. That proposal would be the
subject of a detailed Assessment of Environmental Effects
which would form the basis for consultation with those
persons residing in the vicinity of the site, as well as the
general public.
We are not at that stage yet and no decision will be made
until the short listed consultation process is completed
and the results of that consultation have been taken into
account.
We stress again that no decision has been made by
Watercare as to which site will be chosen as the site for the
new Water Treatment Plant.
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An Auckland Council Organisation
Western water supply strategy – Huia Water Treatment Plant replacement
Questions and answers
Q. Where is the Huia Water Treatment Plant located?
A. The naming convention for the treatment plant has caused some confusion. The plant is not in Huia but is located in Woodlands Park Road just west of the intersection with Scenic Drive and Exhibition Drive.
Q. Why does the water treatment plant need to be relocated and why now?
A. The existing Huia Water Treatment Plant on Woodlands Park Road is 90 years-old and nearing the end of its operational life – a new treatment plant needs to be developed to ensure Auckland continues to receive water.
Q. When is the final decision expected?
A. Watercare is very aware of the anxiety the consultation process has caused for some in the affected communities. However, we are following due process that is essential for obtaining the necessary approvals to locate and construct a new plant. It is important that we do not prejudice the outcome of this process which must run to the final decision to be defensible. The project team is currently undertaking additional investigations on the short-listed sites and considering community feedback. A final option is expected to be ready for Watercare management and board consideration by the end of June. Watercare expects to be ready to lodge applications for statutory approvals soon after in 2017.
Q. Why was the community not consulted any earlier about these plans?
A. A focus group was established in November 2015 to review the process for selecting alternative sites. The group consisted of representatives from the wider Waitakere community including the Local Board, the Department of Conservation and the Waitakere Ranges Protection Society and representatives from the location of the existing plant. The role of the focus group was to review the site identification principles and process. However, they played no part in site selection. The original 44 sites were gradually reduced to a short list of three sites (two sub-sites in Parker Road) via a multi-criteria assessment (MCA) approach. This approach is commonly used by
Watercare and other entities evaluating large-scale infrastructure projects. Earlier consultation on a wide range of sites was not undertaken as it would have raised unnecessary concern among many different communities.
Q. Why did Watercare not attend the second meeting in Oratia?
A. Watercare originally scheduled one drop-in event in Titirangi and one in Oratia. In response to a request from the Oratia community we agreed to a public meeting. We listened to feedback and responded to questions and the views of the Oratia community were made very clear. A second drop-in session was organised for Oratia when the original clashed with the school picnic which was subsequently postponed. When Watercare became aware the second drop-in was again intended to be run as a public meeting a decision was made to cancel. While public meetings provide a strong collective community voice, our attendance at a second meeting was not seen as a constructive or helpful way of gaining additional information for Watercare’s process. We continue to welcome feedback via our project email at [email protected] and are responding to questions as they arise.
Q. Why don’t you just build it on the existing site?
A. Should the preferred option be to rebuild on the existing site, the current plant would need to stop production to allow demolition and construction to take place. We have not yet completed the detailed analysis of the time required to complete this but it would be somewhere between two to three years. There is no opportunity to run the plant on low flow during the upgrade.
Huia Water Treatment Plant has an unconstrained peak production of 126ML/d and currently can supply around 20 per cent of water to the metropolitan area of Auckland. The headroom (or “spare” capacity) available at all of the plants is insufficient to make up this capacity. Therefore, to enable the plant to be shut down, a new supply of water would be required to meet demand during the construction period.
Watercare’s Asset Management Plan currently envisages the upgraded Huia being available 2023 and then the next new source of water (an additional treatment plant on the Waikato River) in around 2032 and then a further expansion around 2048.
To enable the short-fall of closing Huia Water Treatment Plant down would require both stages of the new Waikato Water Treatment Plant being constructed prior to Huia decommissioning.
In addition to bringing forward the new Waikato Water Treatment Plant and network upgrades, we would need to immediately complete the Huia Water Treatment Plant replacement. So in effect, the expenditure that was planned to be funded over 25 years will need to be spent within a six-year period.
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Western water supply strategy – Huia Water Treatment Plant replacement
The importance of the Huia Water Treatment Plant to the resilience of Auckland’s water supply was highlighted during the extreme wet weather event in early March 2017. Extreme rainfall intensity in the Hunua Ranges resulted in slips and sedimentation in some of the supply dams. As a result of this silt, Ardmore Water Treatment Plants production had to be significantly scaled back. The availability of the Huia Water Treatment Plant during this time was essential in ensuring Auckland did not run low on water.
Q. Why don’t you build it in an industrial area or closer to the northern growth areas?
A. Elevation is one of the most important factors determining the location of the water treatment plant. Most of Auckland’s water is supplied by gravity and is then distributed to local communities along the way. Gravity flows reduce the cost of service over the life of the treatment plant and also ensure water can still be supplied when there is a power outage. All the short listed sites meet the key requirements for elevation. The operational costs of a site at lower elevation among industry is expected to be $5.6 million per year, $2 million more per annum than the short-
listed sites.
Q. Why can’t the treatment plant be located in the dam catchments?
A. It is very important to minimise potential impacts on the source water. The western dam catchments are located in the heart of the Waitakere Ranges and their pristine nature helps to ensure the source water is of a high quality. There is no easy road access and a treatment plant and all the associated infrastructure including roads and services would compromise the security of these catchments and would be almost impossible to consent.
Q. Have you considered building two smaller treatment plants?
A. There are significant economies of scale and efficiencies to building one plant on one location as opposed to two separate plants which would both require construction contracts, pipelines, services and staffing. Watercare has a statutory responsibility to be a minimum cost operator ‘collectively’ to all the people of Auckland and such inefficient options could not be appropriately justified.
Q. The Waitakere Water Treatment Plant is older than the Huia plant. Why has this plant not yet been replaced/
upgraded? Why was this site not considered as an option for the future treatment plant?
A. The Waitakere Water Treatment Plant is located on Christian Road. The plant has a peak capacity of only 20 ML/day
and is supplied by only one source - the Waitakere Dam, which is geographically separated from the four Huia supply dams and sits at a higher elevation.
Planning for the replacement of the Waitakere Water Treatment Plant is being investigated with a full upgrade scheduled in Watercare’s Asset Management Plan to start in 2029.
Q.
Is there plans for the new Huia Water Treatment Plant to treat more water and if so where is the additional water coming from?
A.
The output of the dams is fixed due the dams and their catchments physical characteristics – the existing raw water aqueduct allows for a peak abstraction of 140 ML/day from the current four dams. As part of the facility planning process, Watercare is assessing the feasibility of Waitakere dam water being diverted to the proposed Huia Water Treatment Plant allowing for a total Huia capacity of up to 160 ML/day production. As there is no intention or desire to build more dams in the Waitakere Ranges, there will be no need to increase the capacity of the plant from the proposed 140/160ML/day production capacity.
Q. Will we be able to join the Community Liaison Group?
A. The initial focus group always had an open membership and other representatives are welcome to join. When Watercare decides on the final preferred site we will establish a new Community Liaison Group to work through the next stages of the project.
Q. Did you use the public works act to purchase 130 Parker Road?
A. No. Watercare aims to negotiate a private sale in the first instance. 130 Parker Road was purchased in November 2016 via a willing seller and willing buyer arrangement. The purchase of the property helps Watercare maintain access to the site as an option without having to acquire more expensive developed land at a later date. Immediate landowners around 130 Parker Road were notified at the time the property was purchased. Utilities like Watercare often buy land in advance of proposed works and sell the land if it is not required at a later date. Watercare recently sold surplus land at Taupaki which had originally been purchased for operational purposes some years earlier.
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Western water supply strategy – Huia Water Treatment Plant replacement
Q. Your plans show my property and house is affected – why didn’t you talk to me first?
A. The technical documents include standard overlays of treatment plants for concept illustration purposes only. The location and associated configuration of a final plant, including any properties that would need to be acquired is still to be determined. When we know the preferred plant location the first people we will talk to are directly affected property owners.
Q. Is Parker Road already the preferred site and does Watercare own other property in Oratia?
A. No. All options are considered equal at this stage. No other land is owned by Watercare in Oratia.
Q. Surely it is cheaper to build at Titirangi as all the pipes already go to that plant?
A. No. Not only is the existing water treatment plant aging but many of the raw and treated water pipelines are also getting older and will need replacement. A new watermain (North Harbour No. 2) also needs to be constructed between the new plant and north west Auckland.
Q. Was the property at Manuka and Woodlands Park Road purchased at the same time, or in parcels?
A. The Watercare land at Manuka Road and Woodlands Park Road was purchased in the 1920s. Watercare holds no records on how the land was purchased.
Q. Why did Watercare not maintain the land at Manuka Road?
A. When Watercare became responsible for these sites they were already covered in a lot of vegetation. In the early 2000s several caretaker’s cottages were removed from the land. Light scrub has grown in their place but the sites are still accessible. The general protection overlays mean that a precautionary approach is still required to all vegetation management in this area.
Q. Please could you explain the circumstances around the removal of the caretaker’s cottages?
A. There were six houses – four were on the Manuka Road site, two on the Woodlands Park Road property. The houses were erected on the sites to provide accommodation for staff at the treatment plants and laboratories. This was a common practice at the time, as for school, police houses, etc. In the 1990s staff had moved out of the houses. Five of the houses were sold and relocated and one was demolished.
Q. The Titirangi sites are about trees, the Oratia sites are about people – surely people are more important than trees?
A. This project is about delivering water to Auckland for the next 100 years. The Huia Water Treatment Plant supplies around 20 per cent of Auckland water. Many factors have to be considered and Watercare is tasked with making the right decision for all the people of Auckland. Social factors are an important consideration but not the only one. Watercare has to make informed decisions based on many factors to ensure we select the right option.
Q. How will the social and ecological impacts be considered in the final site selection process?
A. A similar multi-criteria process will be followed for the final stages of the site comparison assessment. However, the information we are now collating is considerably more detailed and will help better inform the decision making
process. Many factors will influence the final decision including physical site constraints and constructability, capital and operating costs, effects on the community including social, economic and cultural effects, landscape and visual
effects, environmental and ecological effects including habitat disturbance, effects on physical and natural resources, traffic and social effects for both construction and operation, consenting and property risks as well as mana whenua related issues.
Q. Won’t a new Plant destroy the local community?
A. Watercare is building and running assets all over Auckland. We will always look to work with local communities and make positive changes where we can. Watercare often becomes part of a community for a long period of time and we want to show we can act as a good corporate citizen and neighbour.
Q. Surely Watercare can’t cut down a whole lot of trees to build a new plant?
A. The Manuka Road site in Titirangi has a significant ecological area overlay within the Unitary Plan. This makes approvals for removing trees more difficult but does not preclude it. Some of the Parker Road site is also vegetated.
Q. How long will construction last for?
A. Construction could take at least two years depending on the site chosen and extent of works. The impact from construction will depend on the location and layout of the final plant design. All works will be managed in accordance with resource consents.
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Western water supply strategy – Huia Water Treatment Plant replacement
Q. Will the Parker Road site result in the road being pushed through to Arataki?
A. There are no plans to extend Parker Road.
Q. Will you need to cut down vegetation?
A. The Manuka Road site would require extensive vegetation removal but there may be an opportunity to protect some of the more significant trees. Construction at the Parker Road North site would result in little vegetation loss. Parker Road South would require more vegetation removal. Special covenants on the bush will be recognised. In fact, vegetation would be protected and even enhanced as buffers are created and planted.
Q. Do any of the kauri trees on the Manuka Road site have or show symptoms of kauri dieback disease?
A. The ecological reports to date indicate no evidence of kauri die back.
Q. Will the pipeline construction result in clear felling of tress and bush along the route?
A. Modern pipeline construction technology includes directional drilling and tunnelling in addition to the more traditional open trenching. In this way we can minimise the effects of pipeline construction on vegetation.
Q. What is the quality of water discharged into the local stream from the plant?
A. The facility includes a storage lagoon which is normally dry. This is used to hold any off-spec water before it is discharged under controlled conditions into the local watercourse. The discharge would be managed under specific resource consent conditions designed to protect the environment.
Q. Will the off-spec water discharges from the treatment plant impact on downstream waterways?
A.
The water treatment plant will have a dry lagoon that will from time to time hold water if process outages or off-specification water occur. There are very few off-specification water discharges from the existing Huia facility and these would be even lower from a new automated plant. The design of any new facility will also minimise the volume of water discharged to the lagoon. Detailed design processes are not yet underway, but future discharge management will focus on the return of this raw water back to our dams where it can be reused. Any water discharged from the site itself, will be discharged in a controlled manner via an onsite storage lagoon ensuring effects on the environment are managed in accordance with resource consents.
Q. How many truck and people movements would there be at the new plant?
A. The current plant has approximately 10 truck movements per week with additional traffic from up to 15 staff located at the site during normal working hours. Construction traffic would be more frequent, however, this has yet to be determined.
Q. What effect will the works have on local roads?
A. Watercare must work closely with Auckland Transport when accessing local roads and undertaking construction. We must also comply with resource consent conditions which will include traffic movements in order to avoid, remedy or mitigate adverse environmental effects?
Q. What would the new plant look like?
A.
The new water treatment plant will be designed to integrate aesthetically with the surrounding area wherever possible. Process areas will be covered helping to reduce noise and effects. Extensive landscaping and planting would also be undertaken helping to screen the plant and reduce visual impacts.
Q. Will there be power pylons supplying power to the new plant?
A. No, large power supply transmission pylons will not be used. The plant is gravity operated so power demand can be managed via underground power supply, cable or overhead on existing power poles, or both. Watercare will work closely with power infrastructure providers to ensure that most appropriate solution is delivered.
Q. How much noise will the plant make?
A. Most of the processes utilise gravity and are non-mechanical so noise can be limited. The design of a new plant would minimise any ‘noisy’ components ensuring all regulatory noise limits can be met.
Q. How much light will the plant generate?
A.
Lighting will be required for safety purposes and will be designed to minimise any light spillage. Access lighting will be sensor based and designed for safety.
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Western water supply strategy – Huia Water Treatment Plant replacement
Q. Will chemicals be located on site?
A. Yes, process and disinfection chemicals will be stored on site. All statutory and legal requirements are meet with regards to storage and use to ensure safety. Watercare runs other treatment plants, such as Onehunga which is in close proximity to private property and a local school.
Q. Is Exhibition Drive to be sold by Watercare?
A. No. Watercare has no intention of selling exhibition drive land which it owns for water supply purposes. The public amenity value of the drive is very well recognised. Watercare is working with Auckland Council on a potential offer back so as the land can remain as part of the regional park.
Q. Will a new treatment plant at Manuka Road affect public access to Exhibition Drive?
A. No. However, there could be some temporary restrictions during a construction phase.
Q. Why did Watercare not challenge the special ecological overlay in the Unitary Plan which covers land including the Manuka Road site?
A. The Waitakere District Plan applied a Special Ecological Area Overlay on the Manuka Road site. This became a regional overlay under the provisions of the new Auckland Unitary Plan. Watercare worked with the Council on the unitary plan but like other CCO’s did not submit on any aspect of the plan. Our main focus was on provisions that would more easily enable Watercare to undertake its statutory duties to provide water and wastewater services. We also considered a precautionary approach was required irrespective of the designation due to the significance of vegetation in the Waitakere Ranges. As such, we assumed resource consents, including alternatives assessments, would ensure that any activity within the overlay would be subject to appropriate levels of scrutiny and robust assessments.
Q. What is being done to secure more water sources for Auckland as the city continues to grow?
A. Watercare has a resource consent to abstract water from the Waikato River. This consent allows up to 150 million litres per day to be drawn from the River. Accordingly, the Waikato Water Treatment Plant is sized to the limit established within the consent. To meet future growth and increased demand for water, Watercare lodged an application with Waikato Regional Council in December 2013 for an additional consent to abstractup to 200 million litres of water per day from the River. A new water treatment plant and associated facilities was proposed to be built to utilise this additional water. This application has not yet been considered by the Council
as other applications lodged ahead of Watercare’s are required to be heard first.
Q. We haven’t had a chance to make submissions on the project when will we get that chance?
A. At this time Watercare is socialising the project with the communities surrounding the short listed sites and listening to feedback. The communities will continue to have an opportunity for a say and can do so via our website or project email [email protected]. The public will also be able to make submissions as part of the statutory process once a final option has been determined and the application lodged. These submissions will beheard by independent commissioners.
Q. What is the process for objections to the final decision?
A. When Watercare has made a decision on the preferred site an application for resource consent or notice of requirement will be lodged with Auckland Council. This will be notified and the community will be able to make submissions which can be heard by independent commissioners.
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