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a good fit


Cover Page & Current page Puketutu Island - view of quarry July 2012 taken by author




6.2 Site context 6.3 History of Puketutu Island

3.0 RESEARCH PROPOSAL 3.1 Rationale 3.2 Aim 3.3 Site Introduction 3.4 Puketutu Island Current Proposal 3.5 Methodology 3.6 Reflection 3.7 Definitions

4.0 BACKGROUND RESEARCH 4.1 Quarry industry

4.2 Biosolids 4.3 Contaminants in Biosolids

5.0 CASE STUDIES 5.1 Quarries 5.2 Biosolids 5.3 Remediation 5.4 Sculpture Parks 5.5 Reflection

6.1 Regional context

7.0 DESIGN DEVELOPMENT 7.1 First moves and concept 7.2 Design investigation 7.3 Concept development 7.4 Developed concept





Puketutu Island 1960, looking east from Mangere Watsewater Treatment Plant. Source: Retrieved 2012 from cfm?itemid=90 Opposite page: Puketutu Island c1950

Post Industrial sites, such as quarrying are essentially a temporary use of land, taking valuable resources and exploiting the earth’s surface. As minerals are depleted these disturbed landscapes are abandoned. Disturbed landscapes near the centers of growing cities are emerging as a highly valuable land resource, which is too valuable to be left untouched.

Applying the principles of ‘a good fit’ I have developed a landscape architectural master planning approach, a phased future plan for Puketutu Island that remediates and reveals the past and future through a new park for people.


Puketutu Island has been subject to quarrying since the 1950’s and recently proposed to undertake a rehabilitation project injecting biosolids to reconstruct the island back to its original form, disturbing the island further.







1. Close-up of 1946 aerial view northwest across Puketutu Island volcanic cones showing part of historic landscape now quarried. Source: Whites Aviation Neg. No.2477, Alexander Turnbull Library, National Library of New Zealand, Wellington 2. Puketutu Island stone wall defences c.1948 3. Puketutu Island aerial view southeast over quarry c.1965 Source:Geosmart Ltd, Whites Aviation Neg no 612134 4.Puketutu Quarry c.1965 5.Puketutu Quarry. c.1965 6. Aerial of Puketutu Island c.1965 Source: Auckland City Council Library


How can a landscape architectural master planning approach to disturbed landscapes help to return Puketutu Island to the public?

1958 aerial view east over the quarry, shows quarrying and farm clearing of stonework. Source:Geosmart Ltd, Whites Aviation Neg no 46878

Disturbed landscapes are generally a man made product of Quarrying and Mining extracts from our surrounding landscapes. Quarrying rocks and minerals has been an important resource for building human infrastructure for thousands of years but as minerals are depleted these disturbed landscapes are abandoned.

Landscape architecture is not simply a reflection of culture but more an active instrument in the shaping of modern culture (Corner, 1999)

For landscape to be properly recovered it must be remade, designed, invented a new; it can not simply be restored, as an old painting. (Corner, 1999)

Quarry operations can have a major impact on the surrounding environment, and on nearby communities. As we exploit the earths surface, stripping it of minerals we are left with valuable land areas usually situated near town centers, placing a importance to rehabilitate. Rehabilitation designers need to incorporate information about landscape surroundings, in designing the rehabilitation for any site to achieve greater cultural acceptability. (Corry, 2011). Puketutu Island has been subject to quarrying since the 1950’s and recently proposed to undertake a rehabilitation project injecting biosolids to reconstruct the island back to its original form as an attempt ‘to heal the scars and cover the ugly wounds, but the effects of man’s rude surgery cannot be obliterated’ (Hayward B. W, 2011) I was drawn to Puketutu Island as I saw this jewel of the Manukau Harbour was too precious to be rubbing salt in the wound one last time and felt the Island deserved to shine. With an already accepted plan and no community consultation or champions to speak up for Puketutu Island I see this as prime opportunity to defend this precious gem of the Manukau through returning it to the public. Research by Robert Corry, Raffaele Lafortezza and Robert Brown into what is culturally acceptable for quarry rehabilitation builds on an effort to understand what is a ‘good fit’ for the site and its surroundings. Their research is based on an online questionnaire to gather responses to a series of photographs, the comments demonstrates the importance of using landscape surroundings in rehabilitation design.


3.1 Rationale






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1. Puketutu Island 1960, looking east from Mangere Watsewater Treatment Plant. Source: Retrieved 2012 from heritage/itemdetail.cfm?itemid=90 2. Weeks Island (Puketutu Island) c1910’s_Island.jpg 3. 1946 aerial view north, shows Maori volcanic cone pa and settlement 4. 1946 aerial view northwest, shows farm clearing of Maori stoneworks Source: Auckland city Council 5. Comparison of stone wall remnants 1946 vs 1958 Source: Auckland city Council 6. Puketutu Island GIS aerial photo 2001 showing archaeological sites Source: Auckland city Council

3.2 Aim My intention is to work closely with the current rehabilitation proposal by Boffa Miskell and investigate ‘a good fit’ for the island, developing a Master Planning approach that remediates and reveals past (quarry) and future (biosolids) disturbances using Puketutu Island as a case study. Undertaking a detailed landscape analysis of the site and the wider context and conducting a series of case studies both local and international, that evaluates examples of disturbed landscapes Create a new park for people by revealing, respecting, remediating and returning, that embraces public in recreation, education and art engagement.

Awhitu peninsula

Otuataua Stonefields


Proposed disposal area

Current disposal area

Mangere Wastewater Treatment Plant Rehabilitated lagoon Ambury Regional Park

Aerial of Puketutu Island and its surroundings 2008. Source: Auckland City Council

3.3 Site Introduction Hillborough Auckland CBD

Waitakere Ranges

One Tree Hill

View of photo opposite

Kelliher Homestead Causeway to Mangere

Winstones Quarry

Living Earth

Stonefiels and Auckland Airport

Puketutu Island exists from a series of volcanic eruptions in the Manukau harbour about 30,000 years ago forming the only significant Island in the Manukau Harbour. These eruptions spewed scoria and ash producing 197 hectare of basaltic volcano. Quarry activity has taken place on the western side of the island since the early 1950’s; prior to quarrying it had a cluster of 8 volcanic cones, the highest being 70 m above sea level. The highest Puketutu hill remains only with a few other partial cones. The island today contains the Kelliher homestead, which operates as Dawson’s function centre on the north eastern side, the Quarry operation (west), Winstones Aggregates began on the island in the 1950s and Puketutu’s scoria cones were heavily quarried for fill to extend nearby Auckland Airport and the sewage treatment ponds. Since lease expired in 2011, the operations now bring in clean fill. Living Earth Limited who has recently established a green waste composting facility with a 10 year lease on the island is located on the south side. The island is connected to the mainland at Mangere by a causeway, which crosses the decommissioned sewage settlement ponds associated with the Mangere Wastewater Treatment Plant operated by Watercare Serves Limited (Watercare). The purchase of the island has been passed on through the centuries but today has recently been purchased by Watercare, with the arrangements to dispose of biosolids from the Mangere Wastewater Treatment. Located just 30 minutes from the CBD, Puketutu Island offers some unique experiences and its close proximity to the metropolitan area would make it accessible to a wide range of people. Arriving at the island via the causeway enables you to step into another world and gain a feeling of remoteness even though it is close to the city. From the coastal walkway and summit, Puketutu offers unique views of Auckland and views west across the manukau and the Waitakere Ranges, form Hillsborough to Blockhouse Bay, east to Mangere Mountain and south over the Stonefields to Auckland International Airport.

Boffa Miskell Rehabilitation Plan. Source: Auckland City Council


A report prepared by Boffa Miskell Limited on behalf of Watercare Services Limited (Watercare). The purpose of the report was to assess the potential, natural character, landscape and visual effects in relation to the proposed rehabilitation of Puketutu Island. The proposal aims to utilise biosolids from the adjacent Mangere Wastewater Treatment Plant to rehabilitate the quarried portion of the island, creating new landform. This proposal outlines the proposed vision and enhancement concept for the balance of the island. The proposed rehabilitation of the island is not to replicate its original form but to provide opportunities for the ecological and natural coastal character values, whilst respecting the cultural significance. The report covers a description of Puketutu Island and its surrounding context, considers the provisions of relevant planning documentation and analyses potential landscape and visual effects arising from the proposal. A concept plan (opposite page) includes: • Walking and tramping • Picnicking • Recreational cycling • Recreational horse riding • Educational programmes • Interpretation of history and geology Technical obstraints the proposal dealt with: Completed landform envisioned to be approximately 28 hectare footprint of biosolids (top). The maximin height of the final landform is anticipated to be 39m RL(restriction limit) in the north and fall to approximately 25 m RL in the west. The slop from the east to the west will be at 1 in 70 with a series of steps, and will facilitate for any of the surface water pooling. Embankments surrounding the biosolid area will be built up with clean fill with a slope 1:4 to the outer edge. Biosolid placement will be inserted with in an engineered low permeability liner to stop any leachate generated by the biosolids. Stormwater from active placement areas will be collected and conveyed to the Waste Treatment Plant, once at a suitable quality this will be released into the environment. A final geotextile cover over the biosolid form then 300mm of aggregate and 500mm of topsoil finish the enclosure. Drainage swales run over the landform to spillways.

Top: Proposed extent of Biosolids Bottom: Boffa Miskell Rehabilitation Model Source: Boffa Miskell (2008)

Aerial northwest across Puketutu 1946. Geosmart Ltd, part of whites aviation neg. no 2477

3.5 Methodology INVESTIGATION

I have taken Puketutu Island located at Manukau Harbour, Auckland as a case study to base my year long investigation into the rehabilitation of a quarried site. The current proposal to dump 4.5 million tonnes of biosolids over the next 30 years, transforming the land back to its roughly original state prior to quarrying in the 1950’s. A key involvement in my study came down to the method I used such as literature search, case study analysis, site analysis. This involved an in depth background investigation which includes a literature search of journals, books, internet, news papers, articles and academic papers. Within this literature search, subjects relevant to my project such as biosolid, cultural history, quarrying, soil contaminants and phytoremediation all guided my focus. This led me to a wide range of case studies to analyse how post industrial sites deal with the rehabilitation or restoration after they expire. Based on the principles that have been established by James Corner I was able to pull out of the case studies opportunities and constraints ‘for landscape to be properly recovered it must be remade, designed, invented anew; it can not simply be restored, as an old painting’. (Corner, 1999) Case studies analysed 1.Eden Project, Bodelva, Cornwall, United Kingdom 2.Halswell Quarry, Christchurch, New Zealand 3. Independent Quarry, Isle of Portland, United Kingdom 4. Rabbit Island, Nelson, New Zealand 5.Tiaki Para, Christchurch, New Zealand Puketutu Island itself has limited access due to the quarry operations, as the clean fill process is still in production. Although I have managed to gain one site visit up the last remaining hill the rest has been subject to observations from the wider surroundings and previous site analysis obtained from the Boffa Miskell Proposal, Environmental Court and history books. I was also privileged to have discussions with some of the iwi, council and environmental court representatives.

Once the layers were formed the area was broken down into five manageable areas, each with its own unique attributes and amenities. It was here where I apply the theory Rehabilitation designers need to incorporate information about landscape surroundings, in designing the rehabilitation for any site to achieve greater cultural acceptability. (Corry, 2011) and lead me to uncovering a ‘good fit’ for the island based on the key design driver criteria of Revealing the potential of the site. Respecting - past and future Returning - to the public (wider community) Remediating - cleansing the soil of heavy metals from the biosolids I also refined my views at this point as the theorist James Corner said “For landscape to be properly recovered it must be remade, designed, invented a new; it can not simply be restored, as an old painting”. (Corner, 1999) Investigation leads into each area and also into each of the phases refined my design, collecting each piece of the puzzle to tell the story. During this time I was confronted with areas of research and investigation out of my field and had to make assumptions on the information presented to me at the time.


Landscape interventions, refinement of concept into a final master plan and phased approach. The Master Plan promotes the development of a mixture of programmes by creating settings for a wide range of activities. This appeals to a wider user group and will become increasingly diverse and focused as the community and school groups adaptivity manage the site to suit particular interests and needs. Designing a durable landscape framework that is flexible enough to accommodate change. As well as identifying opportunities for commercial programs such as the mountain bike trail and Living Earth that will help generate revenue and sustain the park. Many of the structures and programs proposed will need to anticipate changing programmatic needs; others may be only temporary, or will need to be relocated over time. The idea is to integrate these facilities into the landscape so as not to detract from otherwise scenic settings.

My interpretation and conclusions are the result of my findings and came from a varied source including maps, reports, photos, drawings, conversations, statistics and site visits. Mapping was a crucial tool in my findings. Areas mapped included site access, patterns in landscape, zoning, topography, existing vegetation, land use, view sheds, boundaries, connections to site, wind direction, aspect, archaeological sites and current movement on site.

The plan proposes an innovative method of reuse of trees after remediation. Some structures could provide the opportunity for artist participation using the remediation and sculpture techniques.


To gain the level of understanding and the potential of the site, cross sections were the ideal method to come to grip with the technical background of the phases . As the site is of a large scale, I concentrated on two areas of the Master Plan to gain more in depth understanding. The core the first of the areas was chosen as this stage is due to commence in 2014 and to gain full understanding of the project this area was to be used as a model for all leading investigation.

Adopting a phasing approach to the Master Plan due to the huge scale and complexity of the site’s transformation. Taking up to 30 years before the park is complete, at which that time a new phase in the park’s evolution may occur With in these phases, smaller scale layers form to build the basis of the project. These layers include: • Circulation and infrastructure • Biosolids • Remediation • Programmes • Structures • Integration

Artists involvement with many aspects of site design, furniture and signage and in the ongoing development and planning of cultural events.

The second area I work with was the North Hill, this is the largest of the five and has the most undulating surface making it the most challenging of the five. With a series of mounds and level changes, this proved to be the most challenging.

Puketutu April 2012 taken by Author

3.6 Reflection My negotiated study project derived from an interest in disrupted & isolated land and has evolved as a result of a passionate concern of providing a careful balance to an existing habitat, while respecting the community, history and cultural significance of the site. I found myself stumbling upon Puketutu Island and with its unique character and amazing opportunities I chose to continue my journey using Puketutu Island as my case study. At the beginning of this project I had thought information regarding the island would be a lot easier to come by but as I researched, it became more evident that the island is a very sensitive issue and people are limited to discussion regarding Puketutu and its future plans. I have identified the key parties involved with the future of the island insight including, Watercare Services Limited, Auckland City Council (formally Manukau City Council & Auckland Regional Council), Kelliher Trust, Living Earth, Winestones Quarry and local Iwi. Unfortunately all parties were reluctant to discuss the on goings of the current project or future for the island. A clear concern of the islands future was evident and the long term issues that may come from the current proposal raised more interest in the biosolids and their adverse effects on the environment. After a conciderable amount of twists & turns and even dead ends I was able to refocus my project. Diving more into Boffa Miskells plan I saw gaps, although I like the concerns for the ecological and natural coastal character values, whilst respecting the cultural significance in there plan, I struggle to see this coming through into the design. I feel this design is only portraying a series of walking tracks for the public and missing the authenticity of the site by using token gestures. Based on what I have gathered on the proposed plan it doesn’t seem to capture the true essence of the island. Although it offers a wide open space for the public it is limited in its appeal and user group needs. I found it surprising to see that all evidence of the quarry is to be covered by the biosolids leaving no trace that industry or an industrial past ever existed. After a gruelling history that left the island so exclusive it now has a chance to become a park for people, revealing the history, respecting the past and future, remediating the soil and returning to the public.

3.7 Definitions POST INDUSTRIAL

Relating to a period in the development of an economy or nation in which the relative importance of manufacturing lessens and that of services, information, and research grows.


Having the place or position changed, interrupted.


To restore to good condition, operation, or capacity.







1. Puketutu Quarry 2012, View of quarry looking east 2. Puketutu Quarry 2012, Machinery 3. Puketutu Quarry 2012, Machinery 4. Puketutu Quarry 2012, View of quarry looking southeast 5.Puketutu Quarry 2012, Machinery 6. Puketutu Quarry 2012, View of quarry looking southeast Source: Taken by Author July 2012


In New Zealand there is solid laws and strategies in place for industries such as quarrying and mining. A compliance is required along with RMA and District Plans over land, air and water quality. The RMA requires every quarry to prepare detailed management plans that detail environmental control, future development and safe operations.

“New Zealand uses 11 tonnes of aggregate per person per year in construction” Winstones Quarry 2012

Quarrying rocks and minerals has been an important resource for building human infrastructure for thousands of years but this industrial-scale quarrying of substances places great stresses on the environment and people are more aware of the environmental impact of quarrying. Quarrying is essentially a temporary use of land, although with rock quarries such use may span the working life of a generation. As minerals are depleted these disturbed landscapes are abandoned.


Puketutu Island was one of only a few sites in the Auckland area where Maori used stone extensively for their building foundations, gardens and other structures. Although most physical evidence has been removed by European activities an important remnant on the western side of the island has been protected by Winstone Aggregates and the Kelliher Trust. Quarrying began on the island in the 1950s and Puketutu’s scoria cones were heavily quarried for fill to extend nearby Auckland Airport and the sewage treatment ponds. Now at the end of its life, Puketutu Island operates as a distribution centre and clean fill before Watercae’s proposed biosolids operations begins 2014.


4.1 Quarry Industry

Biosolids Treatment Process Source: are-biosolids.php

4.2 Biosolids

allows the grit (sand, silt and gravel etc) to settle out. The organic solids remain in suspension. The grit is collected in hoppers and is removed by screw conveyor and is trucked off-site.


Sedimentation tanks The 12 large sedimentation tanks are designed to allow the wastewater to flow slowly through in a smooth motion, free from turbulence, so that the organic solids settle to the bottom. The sludge is collected by scrapers that move continuously along the sloping floors of the tanks. The sludge is pushed into a hopper where it is removed by new centrifugal pumps. Scum, which rises to the surface, is directed by water jets to a rotary scraper and then conveyed to the sludge sump. Sludge and scum are pumped via gravity thickeners and gravity belt thickeners to anaerobic sludge digesters for secondary biological treatment.

Biosolids is treated sewage sludge solid or semi solid which has been collected from the wastewater treatment process (raw sewage and grey water). What you flush down the toilet and plug-holes in your house eventually requires treatment at a sewage treatment plant. A typical sewage treatment plant uses a range of treatment processes to produce recycled water and biosolids. (Opposite page)


Biosolids are produced primarily from the treatment of sewage. Sewage consists of used water from household activities such as washing dishes and clothes, taking a shower, flushing the toilet and even cleaning your teeth. Industry also discharges into the sewerage system. This discharge is usually regulated and limits are set so that any potentially dangerous compounds are not allowed in the sewer at levels that might cause harm to the environment or people. During sewage treatment, microorganisms digest (eat) the sewage, completely breaking down the original organic solids that have been discharged into the sewerage system. This leaves a low solids effluent and a solids component known as biosolids. The water content of the solids is then reduced, usually by passing through mechanical processes. The resultant product is biosolids. Biosolids comprise dead micro-organisms, a small portion of active microorganisms, and any inert solids such as sand which have come down the sewer. Strict state and national guidelines in Australia and New Zealand specify the way in which specific biosolids can be used. The Australian and New Zealand water industries use some of the most advanced wastewater treatment and biosolids production technology and quality assurance programs in the world. This goes toward ensuring the safe and sustainable management of biosolids. The Mangere Wastewater treatment plant use primary (mechanical), secondary (biological) and tertiary (filtration and ultraviolet radiation) methods to treat wastewater comprising of domestic and industrial waste.


Pre-treatment occurs when wastewater from Auckland’s interceptors (main sewers) enters a mixing chamber at the start of the processing. Air is blown into the wastewater to keep it aerobic and to prevent solids from settling out. Odorous air and gases are extracted at this point (and at numerous stages throughout the treatment process) and passed through odour control filters. The wastewater flows into six channels, each capable of taking 2,700 litres per second.


Screening is the first line of treatment at the entrance to the wastewater treatment plant. Here six fine screens intercept solid debris (plastic, paper, leaves, wood etc) from the waste stream. The six revolving drum-shaped, three millimetre screens, are constructed of stainless steel and replaced the old-technology, 19 millimetre screens. The screenings (up to eight tonnes per day) are extracted by screw conveyors, washed and dewatered and transported to a large waste skip which is trucked daily to an off site landfill.


Primary treatment is mechanical and essentially involves separating solids from the liquid waste stream. Grit removal Primary treatment begins after screening in 12 sets of pre-aeration grit removal tanks. Air pumped into the tanks generates a rotary motion which reduces the effective density of the wastewater and


Reactor/clarifiers and biological nutrient removal (BNR) At the heart of the treatment plant lies the land-based secondary treatment system. Secondary treatment is carried out in nine large, circular reactor/clarifiers. Each reactor/clarifier has the capacity to hold 31.3 million litres, equivalent to the wastewater treatment requirements of 200,000 people. The secondary treatment system is known as biological nutrient removal (BNR) and uses a process known as ‘activated sludge’ (sludge with high levels of bacteria.) The system relies on the controlled growth of populations of bacteria to biologically ‘strip out’ organic pollutants (in this case nitrogen and ammonia), and reduce its biochemical oxygen demand (BOD) of the wastewater. BOD is a measure of the strength or pollution potential of the wastewater. In each unit, eight reactor compartments (four anoxic and four aerobic) are arranged concentrically around an inner clarifier. Effluent from the primary sedimentation tanks is fed proportionately (via the interstage pumping station and splitter boxes) into the anoxic compartments of the reactor. Activated sludge recycled from the clarifier is fed into the first anoxic compartment where it is mixed with the incoming primary effluent. This so-called ‘mixed liquor’ then flows through the reactor compartments. Oxygen levels in the different compartments are raised (aerobic) or lowered (anoxic) to select populations of specific bacteria, which break down organic pollutants and remove nitrogen. The effluent is then passed to the central clarifier where the heavier solids, including bacteria, settle to the bottom. This is then collected and recycled back to the reactor to enable the bacteria to go to work again. Discharged waste activated sludge (or WAS) is passed to the dissolved air flotation (DAF) units for thickening. The clarified effluent from the clarifier is then conveyed to the filtration and disinfection plant for tertiary treatment.


Gravity thickeners After primary treatment the sludge, still in very liquid form (about 1.5 percent solids), is passed to the gravity thickeners. As sludge enters the thickener tank the heavier sludge gravitates to the bottom (hence ‘gravity thickeners’). Inside the tank a ‘picket fence’ mechanism slowly rotates, breaking up scum mats, releasing entrapped gas and conditioning the sludge. Once full, the top layer of sludge, which is the most liquid (the supernatant), is decanted over a weir and conveyed via the interstage pumping station to the reactor/clarifiers. The remaining settled sludge is sent to the gravity belt thickeners for further thickening before being fed to the digesters. Dissolved air flotation (DAF) thickeners Secondary sludge or waste activated sludge is discharged from the reactor/clarifiers. Before passing to the digesters it is thickened in the DAF (dissolved air flotation) system. The DAF thickening process works on the opposite principle to the primary gravity thickeners. In the DAF system, waste activated sludge, still in highly liquid form (with a solids content of only 0.2 percent), enters saturation tanks where it is mixed with compressed air and pumped under pressure to the floor of the DAF tank where it is released. The sudden release of pressure causes the air to come out of the solution. Microscopic bubbles adhere to the sludge particles which are then transported to the surface to form a floating blanket. Here a slowly rotating arm skims the top layer of thickened sludge into a float or

Australia’s use of biosolids 2011

Comparison in the end use of biosolids between New Zealand and Australia 2011. Source: are-biosolids. php

New Zealand’s use of biosolids 2011

off-takes compartment. The DAF thickening process increases the solids contents to three per cent – a factor of 15. The thickened sludge is then piped to the gravity belt thickeners (GBTs) for further thickening, while the liquid effluent is passed back to the reactor/clarifiers. Anaerobic digesters There are seven digesters each with an effective volume of 7,450 cubic metres. Sludge digestion is a complex biological process in which the sludge is heated to 37.0oC. Acid-forming bacteria break down the organic materials into organic acids, which are in turn converted into methane and carbon dioxide gases by methane-forming bacteria. Special pumping and mixing equipment within the digesters means the sludge is well mixed and conditioned. The sludge remains in the digesters for approximately 20 days. Gas production Gas production from the seven digesters is 35,000 cubic metres per day. The biogas is a valuable fuel, supplying four 1.7MW gas engine/generators which can also run on natural gas. These engine/ generators contribute to the plant’s electricity demand during normal operation and provide all the heat required for the treatment process.


Ultraviolet (UV) disinfection The land-based tertiary treatment process is carried out in the filtration and UV disinfection plants. The UV disinfection facility at Mangere is one of the largest in the Southern Hemisphere. The plant, which contains the latest UV disinfection technology, is designed to reduce pathogens in the effluent stream significantly. This ensures a very high quality treated effluent entering the harbour. Prior to the disinfection process, secondary treated wastewater from the clarifiers will pass through large anthracite coal filters. Filtration down to a level of 15 microns removes any remaining larger particles to clean the treated wastewater, further enabling maximum UV light penetration. At the heart of the disinfection system is a high performance mercury vapour lamp rated 300 watts covered with a hard quartz tube. There are 12 channels each with three banks of multiple UV lamps – altogether 7,776 UV lamps. The filtered treated wastewater will pass through these channels enabling UV light to kill off remaining pathogens in the water. Intertidal storage basin After UV treatment, the wastewater will be conveyed via the distribution channel, which runs along the causeway to Puketutu Island. Here it will enter the 17 hectare intertidal storage basin from which it will be discharged twice a day, passing through the discharge pump station at a rate of 25 cubic metres per second.


Dewatering plant After approximately 20 days in the digesters, the sludge, reduced in volume by 50 percent, is piped to the dewatering plant. The dewatering plant complex consists of two sludge tanks, a gallery of progressive cavity pumps, a polymer dosing plant, six centrifuges, a conveyor and load-out system. In order to help thicken the sludge and aid its dewatering, a polymer solution is added to encourage the solids to flocculate or stick together in the centrifuges. The surplus liquid (centrate) from the centrifuge process is returned to the front end of the plant via the Western Interceptor. The limed, dewatered sludge now known as process biosolids is conveyed to the adjacent biosolids storage building where it is held in concrete bunkers prior to disposal. The storage building is designed to hold up to four days production of biosolids (1200 tonnes). Biosolids are disposed of onsite in a rehabilitation site, Pond 2. As Pond 2 is filling up fast, Watercare have had to look at alternative sites for the storage of their biosolids. Watercare consider Puketutu Island as a prime location and without the availability of the

island the company would have to truck biosolids to landfills a considerable distance from the plant involving higher costs, safety issues and inconvenience to neighbours. While the lease price for the island is $27 million, there would be an extra saving of up to $22 million over the 35 year project under this agreement as well as the huge benefit to the local residents, with the 30 less trucks a day travelling through the associated nuisances of noise, dust and road damage.

Puketutu April 2012 taken by Author

4.3 Contaminants in Biosolids HEAVY METALS

Biosolids are mainly a mix of water and organic materials that are a by-product of the sewage treatment processes. Most wastewater comes from household kitchens, laundries and bathrooms, which may contain macro nutrients, such as nitrogen, phosphorus, potassium and sulphur and micro nutrients, such as copper, zinc, calcium, magnesium, iron, boron, molybdenum and manganese. In order of importance domestic source of metals is shown below: Cadmium: Chromium: Copper: Lead: Nickel: Zinc:

faeces > bath water > laundry > tap water > kitchen laundry > kitchen > faeces > bath water > tap water faeces > plumbing > tap water > laundry > kitchen plumbing > bath water > tap water > laundry > faeces > kitchen faeces > bath water > laundry > tap water > kitchen faeces > plumbing > tap water > laundry > kitchen

Biosolids may also contain traces of synthetic organic compounds and metals, including arsenic, cadmium, chromium, lead, mercury, nickel and selenium. These contaminants limit the extent to which biosolids can be used. Modern disposal of biosolids can be applied as a fertiliser to improve and maintain productive soils and stimulate plant growth. They are also used to fertilise gardens and parks and reclaim mining sites. (Ministry, 2003) In Australia and New Zealand, biosolids have been used for cogeneration/power production/energy recovery, land application in agriculture (vine, cereal, pasture, olive), road base, land application in forestry operations, land rehabilitation (including landfill capping), landscaping and topsoil, composting, Incineration, landfill, oil from sludge (experimental). Other uses overseas include bricks and construction material, vitrification (glass manufacture), biofuel, fuel substitute (cement works), additive to road base, jewellery. Biosolids are graded according to chemical composition and the level of pathogens remaining after production. Not all biosolids can be used for all applications. Lower qualities are typically used for road bases and mine site rehabilitation. Only the highest grade of biosolids can be used to grow crops for human consumption. Regulators, such as State departments of Health and Environment strictly control the production, quality and application of biosolids in New Zealand. (Ministry, 2003) The total biosolids production of New Zealand is approximately 58,000 tonnes per year of dry solids. The average solids content of biosolids is 20-25% and this equates to around 0.25-0.3 million tonnes of biosolids in dewatered form (also called wet). • • • • • • •

Agriculture: for biosolids which is applied to land for its fertiliser value without value added processing Composting: for biosolids which processed through a composting facility and used for landscaping or other horticultural use; Forestry: for biosolids which is applied to plantation forests to aid tree growth; Landfill: for biosolids which is disposed to landfill; Sea: for biosolids which is discharged to the ocean; Stockpile: for biosolids which is stored, pending future planning, processing or use; Unspecified: for plants which did not respond or for which the end use could not be identified.

Elements that are frequently called heavy metals such as zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb), as well as many that are not often thought of as being (or may not be) metals, such as arsenic (As) and selenium (Se). However, this definition leaves out elements that are usually included when talking about heavy metals such as iron (Fe), mercury (Hg), chromium (Cr) and nickel (Ni).




The Drill Hall Amphitheatre

Geological walk through time





1. Eden Project Sculpture 2. Eden Project 3. Independent Quarry, shows quarries geological walk through time Source: project_synopsis.pdf 4. Eden Project Sculpture 5.Halswell 6. Halswell Quarry 7. Independant Quarry

5.1 Quarry Case Studies Eden Project, Bodelva, Cornwall, United Kingdom opened 17 March 2001. A disused Chin Clay pit is the most popular attraction in Cornwall, with more than a million visitors a year. Two enormous ‘biomes’ built against the pit walls are the main attraction, but with the addition of the incredibly popular Ice Rink in winter months and open air concerts in milder months the site offers so much all year round. The Eden Project is very keen on promoting conservation and the environment and they have fabulous facilities for young visitors to play and learn. Numerous café’s, shops and facilities make this a whole day our for all the family. Thanks to Tim Smit’s vision, he has accomplished the worlds largest conservatories ‘The Eden Projects’ iconic biomes. Inside the biomes are plants collected from around the world, while on the outside you’ll find planted landscapes including vegetable gardens and eye catching sculptures including the famous giant bee and towering robot (opposite page).


After almost 140 years, Halswell Quarry has turned its motors off, ceased operation and begun its transformation into the current Halswell Quarry Park in 1990. Located near Christchurch in a rural setting this 60.4 hectare park provides opportunities for recreation, passive activities, live entertainment and historic sites. There are interpretive panels spread throughout the park explaining the natural and cultural history of the landscape With paths linking to its surroundings this offers a mixed use interest which is popular with the locals. The park includes a Japanese sister city garden, conservation area, quarry amphitheatre and old quarry buildings and it 5 is evident that it has the local support of the community. I see this as a very successful model as it shows a range of activities for different user groups, making it diverse and attracts a wider user group. The reuse of the quarry buildings is a nice touch in reconnecting the history and showing the underlying values the site has to offer.


A tired limestone island in the Isle of Portland is now a remarkable quarry restoration project bringing together artists and architects, naturalists, earth scientists and the local community. A World Heritage Site, the Portlands important for its geology and landform, with its limestone been used to produce some of the most iconic British Architecture including the Buckingham Palace. The project, ‘Living Quarry Landscape’, is centred around the Drill Hall and regeneration plans for Independent Quarry developed by the Portland Sculpture & Quarry Trust. This project represents Portland and everything that is rooted in its people, its landscape and its stone. It brings geology, ecology and culture together and shows how a community working in partnership with artists, designers, education providers and industry can jointly shape the design and sustainable after-use of the quarry landscape. The Isle of Portland has literally been shaped by its geology and 2,000 years of quarrying history, and holds the memory of both geological and human time. With a wide range of activities there is no doubt that the design has met with the needs for this site. This is an outstanding model based on education, culture and cooperation.


All three of these post industrial sites has taken an individual approach to engaging with the community, culture and respect for the land. They are all situated in rural or isolated areas and yet I found all three similar with regards to local community involvement and open space uses for different user groups. They all had exceptional connections to their history and I found the Independent Quarry to stand out the most with its design solutions involving the ex stonemasons in teaching traditions offering new skills of sculpture workshops for local and international students, keeping the traditions alive. The Eden Project has connected with a much wider community, offering spectacular iconic biomes as well as its famous sculptures, it has attracted an audience from around the world and caters for a particular user group interested in plants and art. Much like the Independent Quarry It has had great community support involving local community support and volunteers. Halswell a little closer to home offers a variety of spaces and provides a diverse experience of activities, I see this as one of the more successful case studies in New Zealand. With its amazing links to the wider community and design revealing the industrial past of the site I see this as a very successful example of revealing the geological history. Much like Eden Project it offers interactive experience throughout the park for a wide range of users. Although Eden Project stands above the rest with its high level of publicity it has become a famous spot for visitors from far and wide to enjoy. Independent Quarry I found to be missing a link in terms of ecological remediation yet it claims to be a living quarry landscape. But other than that it is successful bring geology and culture together and is a great example of how a community can come together and work in collaboration with artists. A good choice in case studies.




1. Rabbit Island 2. Fresh Kills



Biosolids from the Nelson regional wastewater treatment plant have been applied to a 1000-ha Pinus radiata plantation at Rabbit Island since 1996. Rabbit Island (Moturoa) is Crown Land that was vested to the Waimea County Council, now the Tasman District Council, in 1920 as a reserve. In addition to the plantation area, there is 300 hectares of recreation reserve. The Island is very flat (maximum altitude 10m) and is made up of predominantly Tahunanui Sand soils with naturally low nutrient and organic levels. The lack of nitrogen in particular, greatly limits Radiata Pine growth. Organic material is almost absent from soil profiles due to previous burning practices for re-establishment. The soils are permeable and provide free root access to the shallow ground water levels which are between 2 and 4 meters below the surface. The island is a very popular recreational asset with some of Nelsons finest beaches and is visited by around 150,000 people per year. Forestry activities are also very important and currently there is a sustainable cut of 20,000 tonnes per year which provides a significant source of income to the Tasman District Council to off-set rates. The biosolids application has been greatly beneficial to trees growing on this site. Effectively they have transformed it from a relative low productivity to a moderately high productivity forest site. However, as is generally found on more productive sites, the increased productivity has been accompanied by some negative influences on wood properties. On the right sites, there is potential for greater use of plantations for the management of biosolids both to solve a waste problem and enhance forest economics.


South Island iwi Ngai Tahu’s has shared its values and issues regarding waste, the key findings of this research reinforces the commonly held concerns by Maori about the direct disposal of waste (biosolids) to land and uncovers a diverse range of traditional practices and beliefs, contemporary issues and experiences as well as pragmatic alternatives and solutions that challenge current waste management practices. From this precedent, it informed me of the important values placed on traditional practices and beliefs in New Zealand are being disregarded in modern times to benefit a selected group of people.

SUMMARY OF BIOSOLID CASE STUDIES Due to the regulation of the biosolid varying from around the world I have only taken case studies from New Zealand. The use of biosolids for reconstruction is a relatively new concept in New Zealand and research is still current, therefore I have taken case studies such as Rabbit island and Tiaki to add to by body of knowledge and gather an understanding of how the public view this as a solution. Tiaki have very strong views on placing the biosolids near edible crops but have no concern with using them in the form of energy of agriculture. Rabbit Island proves that the level of nutrients in the biosolids increases the growth rate of the plants making them more productive. These where both very positive example but both studies avoided the response to the chemicals in the biosolids and potential risks that may occur.

5.3 Remediation Case Studies FRESH KILLS

A current project in New York transforming a public park that is safe, beautiful and accessible, from what was once a dumping site for manhattans waste including the rubble from September 11. The idea is to promote responsible and innovative strategies for environmental sustainability through demonstration, instruction and collaborative investigation as well as provide amenities and attractions that both distinguish the park and draw local, regional and international visitors. The project will be achieved by reconnecting the site to its natural history, local ecosystems and neighbouring communities. Although this is a brownfield site I was more interested in the phased approach that James Corner took in the Master Planning of Fresh Kills. I was able to see similarities in the approach taken to those need to be achieved at Puketutu Island. The management of Fresh Kills and braking it into manageable chunks as a temporal approach works really well, programming the park to be used by a varied user group at all times was very conscious of this when I was able to visit the site in 2010.


A group of scientist have been investigating the effects of plants and the available pool of heavy metal in soil treated with biosolids. I was able to contact Trang personally and discuss the potentials that Salix, a willow species proved to show excellent results in the uptake of chemicals in soils containing biosolid mater. Trang works closely with her team to produce experiment showing benefits in her short and long term studies.







1. Baemillumi Sculpture Park 2. Baemillumi Sculpture Park 3. Olympic Sculpture Park 4. Olympic Sculpture Park 5. Yorkshire Sculpture Park 6. Yorkshire Sculpture Park


In Bukdo-myeon, Ongjin-gun, Incheon Metropolitan City, the three islands of Shindo, Shido and Modo are connected by Yeondogyo (a continuous bridge). For this reason, the three islands are often referred to as the ‘Brother Islands.’ The final island in this series is Modo Island with its very popular Baemikkumi Sculpture Park. Modo Island is becoming famous for the Baemikkumi Sculpture Park located on Baemikkumi Coast. This sculpture park became famous around the country after it was selected as the filming spot for the movie ‘Sigan (Time)’ directed by Gi-Deok Kim. In the park, Sculptor Il-Ho Lee constructed his personal workroom, and on the lawn, he displayed more than 100 art pieces. Some of the pieces are so vivid that they seem to be walking toward the sea. The beach and ocean spread in front of the outdoor exhibition area to create a harmonious natural scene. As Incheon International Airport is located right in front of the park, visitors can see aeroplanes heading to various places around the world. If lucky, visitors can even take a picture of an aeroplane flying above a sculpture.


The Olympic Sculpture Park has transformed a nine-acre industrial site into open and vibrant green space for art. This new waterfront park gives Seattle residents and visitors the opportunity to experience a variety of sculpture in an outdoor setting, while enjoying the incredible views and beauty of the Olympic Mountains and Puget Sound. In late 1999, the Seattle Art Museum and The Trust for Public Land (TPL) announced the successful purchase of the former UNOCAL fuel storage and distribution facility as the site of a future sculpture park. TPL’s expertise in conservation real estate and its mission of creating open space for people were a perfect complement to SAM’s interest in developing a site for public art and sculpture. The nine-acre Olympic Sculpture Park begun in late 2005 when the City of Seattle transferred the former surface parking lot within the Alaskan Way right-of-way to the Department of Parks and Recreation as a park boulevard. This approximately two-and-a-half acre site was leased to SAM for two consecutive 25-year terms, so it can be developed and managed in a consistent manner as part of the Olympic Sculpture Park. Now complete, the waterfront parcel features shoreline plantings that support salmon restoration, an extension of the Elliott Bay Bicycle Trail to Broad Street and a new pedestrian boardwalk that offers a stronger visual and physical connection to Puget Sound.

YORKSHIRE SCULPTURE PARK WAKEFIELD, WEST YORKSHIRE, UNITED KINGDOM The only one of its kind, Yorkshire Sculpture Park is an international centre for modern and contemporary art, experienced and enjoyed by thousands of visitors every year.

Explore open-air displays by some of the world’s finest artists, enjoy fascinating exhibitions throughout four stunning galleries, be inspired by the natural beauty of an historic estate, and get involved in a dynamic line up of events and activities. Throughout its history YSP has organised a wide range of innovative events and activities under the broad heading of learning and community. With the launch of our new Learning Centre in 2011, our improved learning offer includes public sculpture workshops, practical hands-on sculpture courses, guided tours and talks, lectures, outreach projects and school visits. Last year over 40,000 people were engaged in education work at YSP.


From these three case studies I found Baemikkumi Sculpture Park to be similar to my study of Puketutu Island. Located near the airport Baemikkumi offers connections to international visitors offering them a glimpse of the park as they fly in and then a seamless connection to the park once landed. Yorkshire was more passionate about connecting with the public through education offering events with a learning centre for the public to get involved. A great use of interactive activities that engaged the public of a long period of time. All show a connection to the wider public as I found they had all been well marked and this has made them a success. High publicity is a key element to gaining a wider audience then to engage them once on site is a common attribute they all showed. Inspiring art that created with mix medias seems to attract a wider user group.

5.5 Case Study Reflection I found the concept of case studies to be a little disconnected from my project as a basic case study entails detailed and intensive analysis of a single case but in my circumstances I was very ambitious and broadened my study to many topics. I was able to relate to many examples and took key elements from these as a result.




1. Context map of the world 2. Context map of Auckland 3. Puketutu Island current open space and coastal walkways. Source: Auckland City Council


Puketutu Island exists from a series of volcanic eruptions in the Manukau harbour about 30,000 years ago forming the only significant Island in the Manukau Harbour. These eruptions spewed scoria and ash producing a 197 hectare from the remains of a basaltic volcano. It had a cluster of 8 volcanic cones and the island lay untouched by human hands for thousands of years prior to quarrying.

View from Puketutu Island, Mangere Mountain in the background. Taken April 2012 by Author Above: The isthmus of Auckland with the extinct volcanoes, Dr Ferdinand von Hochstetter, 1859. Auckland City Library


The map of the isthmus by Ferdinand von Hochsetter (opposite), portrays a extreme difference to what exists today. Many of the volcanic cones have been disturbed or have disappeared entirely due to the quarrying activities. The materials that have been moved from Puketutu Island have been a main contribution to the Auckland International Airport and the Mangere Sewage Treatment Plant near by.

Left:District Plan retrieved from Right:GIS mapping, aspect and slope of Puketutu Island

6.2 Site Context ISLAND

Puketutu is a small oval shaped volcanic island in the Manukau Harbour, settlement links to Mangere it is connected to the mainland by a causeway which provides the only access to the island. The tidal nature of the Manukau Harbour provides a constantly changing landscape context for Puketutu Island and comprises a series of sandbanks and mud flats at low tides to being fully submerged at high tide. From my observations I noted a lack of development along the mainland creating a sense of isolation at the island and saw a need to reconnect the island back to the mainland.

VEGETATION Source: Retrieved 2012 from http://joelcayford.blogspot.

During my countless site visits it was noted that the vegetation on the island was minimal. Exotic tree species are dominant on the western side of the island, with Pinus on the northwestern corner but due to the extensive quarrying over the years the vegetation has been depleted leaving only shelter belt on the surrounding edges of the island.


Open space is highly connected around the coastal edge from Ambury farm through to Stonefiels and offers great opportunities to link Puketutu into this connection. Coastal walkways are evident along the edge but a little disjointed to the rest of Mangere


From the district plan the entire island is classed under the Mangere Puhnui Heritage zone; a area of soil generally of high quality, have high landscape value, and significant natural and/or cultural heritage values. This also shows the entire island has the character of being waahi tapu, a sacred area and a recognised geological area. Living Earth Site Taken by Author 2012



1. Left over shells after tests on contaminats Taken by Author 2012 2. Sketches of stone walls and pa sites Source: Auckland City Council

6.3 History of Puketutu Island Puketutu, ‘Te Motu a Hiaroa’, the island of Hiaroa, was named after the sister of Rakataura. Puketutu was an important meeting place of iwi groups and was known as the island of Tohunga. The most sacred objects of the iwi were held on Puketutu and there are a number of important burials on the island. Ancestor Poutukeka, is buried there, these places are sacred and they must never be desecrated. Te Arai o Kaiwhare is an estury between Puketutu and the mainland. This was the sacred pathway of the ancestral taniwha Kaiwhare. The wellbeing of the taniwha was dependant on the wellbeing of the Manukau. The wellbeing of the Manukau and the wellbeing of the people must go hand in hand. Tapu can include spiritual restriction, putting something beyond ones power, placing a quality or condition on a person or an object or place; but whatever the context its contribution is establishing social control and discipline, and protecting people and property. Tapu’s were placed on land and areas that contained the bones of the tribal dead, trees and rocks used in the performance of special rites, the sacred schools of learning, tempory houses used for the sick and dying, temporary houses for the lying-in period of rangatira woman and the birth of there babies – any situation that requires the protection and services of the tohunga (specialists). Tapu as a form of social control is very effective. Its natural beauty and proximity to Auckland have made it a desirable asset. The deed books since 1845 reveal a cast of interesting characters including some of the most significant players in Auckland’s history. It is suggested in the studies in 1930 by archaeologist F.G. Fairfield that there was a substantial population on the island going back centuries. Details of an early population are rather sketchy however, with no written records to inform us. Yet recent archaeological investigation for a Resource Management application have suggested that the date of occupation for the island was between 1530 and 1635 AD and some evidence dates back to possible occupation as far as the 13th century. Maori’s communal ownership did not resemble western patterns. Boundary markers suggested arrangements within tribes but the overall ownership of the land, rested on the capacity to defend it. Numerous iwi and hapu today claim ancestral connection and ‘mana whenua’ status over the island including Te Waiohua, Te Akiyai, Te Ahiwaru, Ngati Te Ata, Ngati Tai and Te Kawerua a Maki. The nearest Marae today is Makaurau Marae on the mainland looking across to the island. Four men asserted their ownership of the island in 1845 including Apihai Te Kawau, his son Te Hira, his nephew Paora Tuhaere and another cheif Te Keene Tangaroa (Ngati Whatua chiefs), and sold the island Thomas Jackson with a deed dated 20th March 1845. The quarries significant activity begun with the Massey’s, with the lease being transferred to Wilkins and Davies in the early 1970’s. In the 1980s’ Winstone Aggregates took over. In the 1990’s the trust board came to the view that while intensive pasture use and quarrying had made sense in the 1950’s and 60’s, the islands greatest value now lay in long term environmental sustainability. Mangere sewage scheme started 1954 but had come under server pressure by the 1990’s as they silted up and became less effective. The oxidation ponds where removed by 2002-2003. By 2002 the Kelliher Charitable Trust has settled on a vision for Puketutu: that the effects of quarrying would be repaired and the island returned to farm and park land; and that the island become a regional farm park, available to all. The island of Puketutu is situated in the Manukau Harbour, and is separated from the mainland by a tidal estuary about a mile in width. It was formerly accessible, except at high water, by a hard shellbank spit, but this old-time pathway has now been replaced by a well-formed traffic roadway, thus

greatly facilitating access. The island consists of a group of several volcanic cones, each of which is more or less elaborately fortified according to the best ancient Maori methods. No doubt each of these hills had its particular name, but there does not now appear to be any record of such, if they ever were recorded. Topographically, even when closely viewed, these hills appear as if one. The western most and highest cone is the most conspicuous on the sky-line. It culminates in a graceful pinnacle, and hence no doubt the appropriate Maori name—Puke-tutu (Pinnacle-hill)







1. Paramount chieftain Kawau, of the powerful Ngatiwhatua tribe. Printed by Gottfried Lindauer, 1874. Auckland Art Gallery 2. Paora Tuhaere in later life, c.1870s photographed by C. Spencer. Auckland City Library 3. James Farmer (1852). James Farmer, c1867. Auckland War Memorial Museum, Album 69 4. John Campbell (1872?). John Campbell , c1899. Auckland City Library




5. Robert Hall (1895) – Robert Halls sons, James & Arthur 6. John Massy & sons, Wellesley & Alfred Charles (1913). John Massy. as president of the Auckland A&P Association, 1907/8 7. Harold & Kathleen Bull (1919). 8. Harold Carr Bull & Kathleen (Cassie) Bull 9. Henry (Harry) Killiher (1938-1940) £? – Kelliher Charitable Trust (1963) Opposite page: Weeks Island (Puketutu Island) c1910

Time line of Ownership for Puketutu Island

1945 -1948

Thomas Jackson (£15)

1848 - 1849

Henry Weeks (£200)

1849 - 1852

John Chadwick (£200)

1852 - 1852

James Farmer (£550)

1852 - 1895

John Logan Campbell (£?)

1895 - 1913

Robert Hall (£4,000)

1913 - 1917

A C Massey (£24,000)

1917 - 1919

John Massey

1919 - 1938

Harold Carr Bull (£26,000)

1938 - 1991

Henry J Kelliher

1991 - 2009

The Sir Henry J Kelliher Charitable Trust

2009 - 2012

Kelliher Charitable Trust


Watercare Services Limited ($25-27 Million lease)


Auckland City Council (management for 999 years)

THE CORE - 152,500 m2

THE GROVE - 120,000 m2

SOUTH STRIP - 222,300 m2

NORTH HILL - 218,500 m2

EAST PARK - 200,000 m2



First moves & concept

The Master Plan envisioned steady, intelligent and flexible growth, with public participation throughout the anticipated 30-year period of park development. Adopting a phasing approach to the Master Plan due to the huge scale and complexity of the site’s transformation means that the process will inevitably take time. Taking up to 30 years before the park is complete, at which that time a new phase in the park’s evolution may occur, as new uses and desires demand adaptation and modification of the park’s landscape.




Biosolids: introducing 4.5 million tonnes over the 30 year period

Remediation: the adverse effects that the site has experienced

Programmes: introducing new educational possibilities including cultural history and heritage trails

Structures: facilities that can accommodate a range of future uses.

Integration: preserved historic resources and new spaces

Once the layers were formed the area was broken down into five manageable areas, each with its own unique attributes and amenities. The Core begins the first stage of the Master Plan with 2,166,239m3 of biosolids deposited in the first 5 years. The core is expected to be fully functioning by the 10 year mark offering a distinct character to the area. Programming will include the use of the pond for low level water sports, recreational and open space for community days and markets. This space is a durable landscape, flexible to accommodate change. The Grove is the second areas of the Master Plan, offering a wide range of education opportunities to reveal the past and future stories the site has to tell. Interpretive trails take the visitor on a journey through time. South Strip creates a mixed use area ideal for quite peaceful leisure, picnicking and offers stunning views out over the manukau to the Waitakere Ranges. North Hill is later in the phased approach but a crucial stage to the master plan. This is one of the largest areas of biosolid deposit with 3,058,219 m3 over 5 years beginning 2029. The North Hill area is the most undulated of all 5 areas offering programmes such as mountain biking with its varied levels this is a ideal spot for recreation.


East Park is the flattest areas of the five offering a range of temporary activities form recreation, market days and community and school events. The goal is to focus on a single location and to program activities and improvements in all five areas in phases. Within the first 5 years surrounding access routes will be in use and within 5-10 years, visitors should be able to picnic in outer areas as well as have full functional use of The Core.



With in these phases, layers form to build the basis of the project. These layers will include: • Circulation and basic infrastructure: including roads, paths and trails that open up the site and extend new circuits of circulation

Puketutu April 2012 taken by Author



Design Investigation


The term ‘open space’ has many meanings. It can mean all land, public and private, that is not covered by buildings.‘open space’ is an area of land or a water body to which the public has a level of free physical or visual access. This definition encompasses both ‘public’ and ‘private’ open space recognising the role they both play in achieving the outcomes sought for the regional open space network.


Open space includes the ‘green spaces’ such as parks and reserves used for amenity purposes and for the protection of biodiversity and cultural heritage. It includes sports fields and recreation areas that may contain buildings and structures designed to facilitate physical activity. It includes the ‘blue spaces’ such as the region’s waterways and harbours. It includes the ‘grey spaces’ such as civic squares, streetscapes and the transport corridors. It also includes the open vistas and views that surround the city. Creating a variety of experiences and open space where visitors can learn from the ecological systems that would further an understanding of the dynamics of disturbed landscapes.


The estimated 4.5 Million Tonnes over 30 years is to be deposited into the quarry area and reconstruct it back to an original form. With a few calculations below and by working in cross section with the level changes I have worked out each area to accommodated this amount.


ton, register cubic meter (m3) 1 2.831685 10 28.31685 100 283.1685 4,500,000 tonnes x 2.831685 = 12,742,582.5 m3 Completed landform envisioned to be approximately 28 hectare footprint of biosolids. The maximin height of the final landform is anticipated to be 39m RL(restriction limit) in the north and fall to approximately 25 m RL in the west. The slop from the east to the west will be at 1 in 70 with a series of steps, and will facilitate for any of the surface water pooling.


Embankments surrounding the biosolid area will be built up with clean fill with a slope 1:4 to the outer edge. Biosolid placement will be inserted with in an engineered low permeability liner to stop any leachate generated by the biosolids. Stormwater from active placement areas will be collected and conveyed to the Waste Treatment Plant, once at a suitable quality this will be released into the environment.

1.Phyto - Volatilisation

Some plants take up volatile contaminants and release then into the atmosphere through transpiration. The contaminant is transformed or degraded within the plant to create a less toxic substance before and then released into the air.

2.Phyto - Degradation

3.Phyto - Stabilisation

Plants take up and break down contaminants through the release of enzymes and metabolic processes such as phytosynthetic oxidation/reduction. In this process organic pollutants are degraded and incorporated into the plant or broken down in the soil.



Some plants can sequester or immobilse contaminants by absorbing them into their roots and releasing a chemical that converts the contaminant to a less toxic state. The mechanism limits the migration of contaminants through water erosion, leaching, wind and soil dispersion.

4.Phyto - Extraction

Plants take up contaminants, mostly metals metaloids and radionuclide with their roots and accumulate them in large quantities within their stems and leaves. These plants have to be harvested and disposed as special waste.



Cd Cr Cu Pb Ni Zn Hg Se Fe Phytoremediation process Source: Retrieved 2012 from


Phytoremediation uses plants to remove pollutants from the environment. The use of metal accumulating plants to clean soil and water contaminated with toxic metals is the most rapidly developing component of this environmentally friendly and cost effective technologies (Raskin, 1997). This process can be carried out in four ways; phytoextraction, phytovolatilisation, phytostabilisation and phytodegradation. Phytoextraction is typically the accumulation of metals in plant material followed by the removal of contaminants from the site altogether. This is carried out by the use of plants known to be heavy metal hyperaccumulators (Reeves, 2006). Phytovolatilisation Phytosabilisation works by using plants to stabilise a contaminant within the soil profile, this is used to prevent leaching and reducing the chance of contact by organisms ( Phytodegradation is when a plant takes up and breaks down contaminants through the release of enzymes and metabolic processes such as photosynthetic oxidation/reduction. In this process organic pollutants are degraded and incorporated into the plant or broken down in the soil. The proportion of Heavy metal uptake into a plant can vary dramatically from species to species and is also dependant on the level of heavy metals that are found in the soil. Zinc is relatively labile and therefore easily taken up into plant tissue, however, Cu is more strongly sorbed to soil colloids (soil organic matter) and plant uptake is more limited (Smith, 2009). Heavy metal uptake is also dependent on the total concentration of metal in the soil, its bioavailability and soil physico-chemical properties (Smith, 2009). Phytoremediation is an innovative technology that is considered more cost effective than most conventional methods of cleaning up chemicals from soils or ground water. The smaller plants (seedlings) absorb chemicals at the surface while larger trees absorb the deeper contaminants with their larger root system. This method of phytoremediation provides a solution for the clean up of chemicals with minimal disturbance to the site. Less machinery, labour and equipment is required compared to other methods, as once established each plant does all the work. Not only does this method offer a cost effective solution but enhances the site aesthetically offering amenity values and clean air long after the clean up process is completed. Phytoremediation is a tested theory that has been proven for years. Plants take up the chemicals through their roots, stems and leaves and break them down into a less harmful form. The time for each clean up is depended on the site itself, level of toxic material in soil, number of plants and variety of plant species.


Tree shaping (also known as Pooktre, arborsculpture, tree training, and by several other alternative names) is the practice of training living trees and other woody plants into artistic shapes and useful structures. There are a few different methods[2] of achieving a shaped tree, which share a common heritage with other artistic horticultural and agricultural practices, such as pleaching, bonsai, espalier, and topiary, and employing some similar techniques. Most artists use grafting to deliberately induce the inosculation of living trunks, branches, and roots, into artistic designs or functional structures. To achieve these art forms, many different tree species have been used, but some trees are better suited than others. Tree shaping has been practiced for at least several hundred years, as demonstrated by the living root bridges built and maintained by the Khasi people of India. Early 20th century practitioners and artisans included banker John Krubsack, Axel Erlandson with his famous circus trees, and landscape engineer Arthur Wiechula. Contemporary designers include “Pooktre” artists Peter Cook and Becky Northey, “arborsculpture” artist Richard Reames, and furniture designer Dr Chris Cattle, who grows “grownup furniture”. This sculpture park offers a connection to a wider community providing a public space programmed to offer people opportunities to reconnect with the site. With the proximity to the airport, Mangere mountain this location is a prime opportunity to key into not only the locals but offers a world class sculpture park for tourism and revenue generation.





1. Manuka flower. Source: Retrieved 2012 from 2. Manuka shrub Source: Retrieved 2012 from 3. Salix x reichardtii Source: Retrieved 2012 from 4. Salix x reichardtii Source: Retrieved 2012 from 5. Salix matsudana showing the branches of the tree Source: Retrieved 2012 from 6 Salix matsudana, showing the leaf of the tree Source: Retrieved 2012 from




From my research into phytoremediation I found the willow family to be one of the most common plant species used for the uptake of chemicals in the soil. Two species in particular have been tested and were the most suited for the up take of chemicals in biosolids. Salix matsudana and Salix reichardtii which I found from a technical research report have both been trailed amongst a series of tests and stand out from the rest in the levels of chemicals they can take up. (Laidlaw, 2011) From here I stared to explore the opportunities in New Zealand native species to see if they could be used as well as the willow species. I was able to track down a recent study that proves the Manuka has similar qualities in chemical uptakes to those of the willows. (Prosser, 2011) Due to the coastal exposure of the island and its location within the Manukau Harbour opportunities and constraints of these plants. I was limited to a selected few as not only did they have to cover the criteria of coastal and phytoremediation qualities but also be able to be manipulated into forms of art such as sculptures (aroborscultpute).

MANUKA (Leptospermum scoparium) Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Myrtales Family: Myrtaceae Genus: Leptospermum Species: L. scoparium

Manuka, Leptospermum scoparium is a New Zealand native also commonly known as tea tree. This evergreen woody tree can be found throughout most of the country and grows to a height of 2-5 meters. (Perry et al., 1997; Stephens et al., 2005).

WILLOW (Salix reichardtii) Kingdom: Plantae Division: Magnoliopsida Class: Magmoliopsida Order: Malpighiales Family: Salicaceae Genus: Salix Species: S. reichardtii

Salix reichardtii is a semi-fast tree up to 10m, this multi-stemmed shrubby tree grows in conditions tolerant of dry salt winds and can handle acid soils. Ideal uses: include soil conservation and windbreaks.

WILLOW (Salix matsudana) TORTURED WILLOW, CORKSCREW WILLOW Kingdom: Plantae Division: Magnoliopsida Class: Magmoliopsida Order: Malpighiles Family: Salicaceae Genus: Salix Species: S. matsudana

A fast growing, upright, deciduous tree, with curiously twisted shoots. Leaves are bright green, lance-shaped, and also twisted. Bears yellow-green catkins. The shoots of this tree are often used in dried arrangements. A very striking tree, especially in winter, so give it a prominent place in the garden.


It is an extremely hardy species, tolerant of varying conditions including infertile and dry soil, or swamp-like habitats. Manuka’s hardy nature makes it a very good species for planting on sites planned for revegetation and rehabilitation, and being a pioneer species it encourages the subsequent colonisation of land with other indigenous plants.

7.3 Concept development

























The Strip

The Grove

East Park

The Core

North Hill

Maori Gardens

North Hill Bus Park

The Core


The Grove

Picnic area Pond Launching spot Toilets Maori gardens Coastal walk Car Park Existing Kelliher Homestead Educational trail Mountain bike trail Horse riding Educational cabins Information centre Restaurant/Cafe

Causeway to Mangere Puketutu Hill East Park

The Strip

Maori Gardens

Car Park

7.4 Design Development The master plan optimises connectivity, access and movement within and beyond the site, facilitating both local and regional access to major destinations in the park. Allow all areas of the park to be accessible to all people at all times. Integrate vehicular drives into the landscape creating slow (40 km/h), scenic driving experiences A variety of paths and trails allow for extensive movement and enhance the park experience with an extensive circulation network, including specially designated paths for walkers, cyclists, runners, mountain bikes, horse riding, hiking and boating access. All paths are separated from roads, with special pedestrian crossings as needed to facilitate safe passage. Use of roads and pathways to help orient visitors in the park through varied materials, signage and signature design Waterfront access is accommodated by numerous docks and launches around the waters edge. The Master Plan aims to promote the development of a mix of programs by creating settings for a wide range of activities. Over time, the park program will become increasingly diverse and focused as the community and school groups adaptivity manage the site to suit particular interests and needs. Create a distinctive programmatic identity for the park that is contemporary, productive, active, incorporating nature, art, leisure, recreation and education. Durable landscape framework that is flexible enough to accommodate change. Organise and stage park programming around existing natural resources and site features, including ongoing biosolids landfill closure, remediation planting, maintenance and monitoring operations. Identify opportunities for commercial programmes Living Earth, Mountain biking, Restaurants and cafes etc that will help generate revenue and sustain the park. Integrate facilities into the landscape so as not to detract from otherwise scenic settings. The plan proposes an innovative method of reuse of trees after remediation. Some structures provide the opportunity for artist participation using the remediation and sculpture techniques. Artists will be involved with many aspects of site design, furniture and signage and in the ongoing development and planning of cultural events.

A A The Core begins the first stage of the Master Plan with 2,166,239m3 of biosolids deposited in the first 5 years. The core is expected to be fully functioning by the 10 year mark offering a distinct character to the area. Programming will include the use of the pond for low level water sports, recreational and open space for community days and markets. This space is a durable landscape, flexible to accommodate change.




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B B North Hill is later in the phased approach but a crucial stage to the master plan. This is one of the largest areas of biosolid deposit with 3,058,219 m3 over 5 years beginning 2029. The North Hill area is the most undulated of all 5 areas offering programmes such as mountain biking with its varied levels this is a ideal spot for recreation.

B 2029


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The Core Opposite: The Core access ramp

North Hill mountain bike trail Opposite: Coastal walk

Horse Riding Opposite: North Hill mountain bike trail

I had no idea this project would have ended this way when I began this journey at the beginning of the year. My passion for the site made me think I could avoid the biosolids and come up with a solution for the island by avoiding further disturbance. But when it came down to reality I would be just pushing the problem somewhere else. Models local and international inspired me to unlock the past and to work with this new landform rather than to stick with traditional methods from the past. With my tests I tried to connect to a local community but as the project evolved it was evident that there was a wider community to connect to and show case the past and future disturbances. Using the surroundings to drive my design, was a crucial point in the phases. Understanding the level of integration and the purpose each small step plays a part in the final outcome became a challenge. I feel that I have come up with a model that links people from beyond the local community making this a destination that can offer a boost to the local economy as new structures appear and visitors are drawn in and embraces public in recreation, education and art engagement.

Puketutu April 2012 taken by Author


“It was unfortunate that the Island has such a hidden past and people are to ashamed to talk about it, I felt if I had the chance to dig into the issues and secret Puketutu had to reveal, the project would have had a very different outcome�.

Puketutu April 2012 taken by Author

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Corry, R.C, Lafortezza, R, Brown, R.D. (2011). Cultural Acceptability of Alternative Pit and Quarry Rehabilitation. Research Report Ecological Restoration 29:1-2 March/June 2011 pg 64-72.

Puketutu April 2012 taken by Author

Laidlaw, W.S, Arndt, T.T, Huynh, D, Gregory, D & Baker, J.M. (2010). Plant-induced changes in the bioavailability of heavy metals in soil and biosolids assessed by DGT measurements. Journal of Soils Sediments, Soils, Sec 3. Langhurst, J.W. (n.d). Rising from the ruins: Post industrial sites between abandonment and engagement. Magdi Selim, H. (2011). Dynamics and Bioavailability of Heavy Metals in the Rootzone. CRC press. United States Ministry for the Environment. (August 2003). Guidelines for the safe application of biosolids to land in New Zealand. Reeves, R.D. (2006). Hyperaccumulation of Trace Elements by Plants. Phytoremediation of Metal-Contaminated Soils. Netherlands: Springer. Raskin, I, Smith, R.D & Salt D.E. (1997). Phytoremediation of metals: using plants to remove pollutants from the environment. Perry, N.B., Brennan, N.J., Van Klink, J.W., Harris, W., Douglas, M.H., McGimpsey, J.A., Smallfield, B.M., & Anderson, R.E. 1997. Essential Oils from New Zealand Manuka and Kanuka: Chemotaxonomy of Leptospermum. Phytochemistry 44:1485-1494. Perry, N.B., Brennan, N.J., Van Klink, Brennan, N.J., Harris, W., Anderson, R.E., Douglas, M.H., Smallfield, B.M. 1997. Essential Oils from New Zealand Manuka and Kanuka Chemotaxonomy of Kunzea. Phytochemistry 45:1605-1612. Prosser, J. (2011). Manuka as a Remediation Species for Biosolids Amended Land. Thesis presentation for Masters of Science. Massey University, Manawatu, New Zealand. Salmon, J.T. (2001). Native Trees of New Zealand 1. Reed Books. Auckland, New Zealand. Stanley, R. (1991). Puketutu Island: A Brief History. University of Auckland. New Zealand Smith, S. (2009). A Critical Review of the Bioavailability and Impacts of Heavy Metals in Municipal Solid Waste Composts Compared to Sewage Sludge. Environmental International 35:142-156 Watercare Services. (2011). Serving the people of Auckland. : 2011 Annual Report. Watson, A. & O’Loughlin, C. (1985). Morphology, Strength, and Biomass of Manuka Roots and Their Influence on Slope Stability. New Zealand Journal of Forestry Science 15:337-348.

Puketutu island