MISSION STATEMENT Merging agricultural processes within an urban fabrication: retaining the land’s sustainability and ecological values of Puhinui whilst providing urban space for the rising Auckland population.
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Contents CONTEXT Introduction to Puhinui Our Rationale Phase 1: Design Driver Phase 1: Proposed Strategy Phase 2: Site Selection
3 4 5 6 7
ANALYSIS Elevation Slope Aspect Hydrology Noise Considerations Viewshed Existing Vegetation
9 10 11 12 13 14 15
DEVELOPMENT Masterplan & 3D Modelling Circulation Building Footprints Vegetation Hydrology Productive Land Public Open Space
17 19 20 21 21 23 24
REFERENCES
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Introduction to Puhinui
Puhinui is presently a 1100 hectare rural backdrop in South Auckland. Situated on a peninsula that extends into the Manukau Harbour, the area is consistant in the coastal characterictics of the Auckland Ithsmus.
PAPATOETOE
The landscape is comprised of small pockets of agricultural and rural land that border commercial and residential areas, the result of an accumulation of physical and cultural processes acting in the area. A brief investigation into the site’s topography reveals a relatively flat landscape prominent in large open spaces of paddock areas, fields, shelter belt planting, outstanding outlooks, and low density rural housing.
PUHINUI
AUCKLAND AIRPORT
The Puhinui area faces significant pressure for urbanisation due to its close proximity to the Auckland International Airport and large adjacent urban centres. MANUKAU HARBOUR
SCALE: 1:30,000
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Our Rationale The Puhinui landscape is a primary agricultural base for Auckland City – siting one of the last remaining food production areas close to the CBD. Values of rural land tend to be overlooked when planning new suburban areas, as taking over vast ‘empty’ landscapes is regarded as the only answer for a city requiring more space for sprawl. However productive rural land is also the key to keeping our city alive – a rising population means an increased need for local food productivity. Thus our objective is to analyse both existing and potential features of the site. Taking into consideration the agricultural processes and ecological habitats present, we aim to develop an urban strategy for Puhinui that will merge agriculture within a new urban realm.
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Phase 1: Design Driver - Multiple Nuclei Model The exploration of a Multiple Nuclei Urban Model is the design driver behind our proposed development strategy. Our intention is to be able to create a selfsufficient urban village in a polycentric environment. A Multiple Nuclei model is an ecological urban model based on planning cities around multiple nodes of activity, rather than sprawling out from one focal point (eg. Auckland’s current CBD). The idea behind this is to create areas of different activities that are appropriate to each others’ functions, and over time the nodes begin to merge to create a single urban area that allows an even spread of both land and urban resources amongst the sprawling city. The diagram shows an example of a Multiple Nuclei urban model, where there are several different nodes located on the landscape which are circulated respectively by commercial zones, and high, medium and low density residential areas. Using a similar model for Puhinui will ensure an even distribution of urban resources in the area while retaining sustainable communities and exisitng land ecologies. 5
Commercial Zone
High Density Residential
Medium Density Residential
Low Density Residential
Phase 1: Proposed Strategy SCALE: 1:30,000
Using the Multiple Nuclei model, we have located our main commercial node towards the centre of the Eastern fringe of Puhinui, extending the current industrial and commercial area that exists in Wiri (on the otherside of the motorway). A second smaller node is located approximately 14 ha to the Southwest of the initial hub. Both nodes are surrounded by high density housing, progressing to medium density housing which extends all the way to the Puhinui Reserve boundary (refer to map). The addition of a second main transport route running through these urban areas and adjacent to the current Puhinui Road, will provide direct access to the new urban and commercial area for residents, workers and passer-by’s alike. The development of new roading infrastructure also allows the opportunity for a proposed light rail link to the airport which can be formed on the existing Puhinui Road. Low-density housing will be located around the rim of Crater Hill - adjacent to Mangere’s existing urban zone. This will be zoned as Residential 3 under the Auckland Unitary Plan, allowing the Outstanding Natural Feature status of Crater Hill to be preserved. Puhinui Reserve will be maintained and protected, with several new urban reserves created on Crater Hill and extending from the Manukau Memorial Gardens - creating green space for wildlife and people alike, as well as enhancing native planting and trees in Puhinui. The important agricultural productivity of the landscape will be preserved, with majority of current productive areas kept for agricultural processes, as seen on the map. 6
Phase 2: Site Selection Further development of a 75 hectare site will be investigated during Phase 2 of the Puhinui Urban Development Strategy. The selected site is outlined in the adjoining images, and demonstrates a mixture of intersecting features from our initial proposal stratgey including: high and medium density residential areas, a commercial zone, a transport hub, and several ecological area’s.
PUHINUI
PHASE 2 SITE
Aerial image of 75ha site showing connectivity to existing land-uses of Puhinui.
In-depth analysis of this focused site, as well as additional research, will assist in the creation of an urban development masterplan for Puhinui.
MANUKAU HARBOUR
SCALE: 1:30,000
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Site in context with the proposed design strategy
Elevation
This analysis demonstrates landform elevation of the site as contour groups, showing an elevation range of 0 - 20.5m above sea level. The North-eastern corner of the site is the highest, but also the flattest terrain as shown by the 1.5m contour lines. While two areas on the Western side of the site illustrate land that is steeper and also closest to sea level - consistant with stream environments.
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SCALE: 1:4,000
Slope Analysis
SCALE: 1:4,000
A GIS slope analysis is broken up into 3 categories: 0-4o slopes and 4-8o slopes are ideal for building on, while 8-15o slopes are generally considered unsuitable for building footprints. This slope map reveals that most of the site is flat and therefore ideal for development; while the few steep zones (shown in orange) are areas where building plans should be retired and riparian planting should become the focus instead.
SCALE: 1:30,000
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Aspect
The following aspect analysis shows all north-facing sites in red - exposing spaces which receive the most sun and are thus generally warmer and drier than the southfacing area’s (shown in blue). It is typical to build houses with living areas north or northwest facing to maximise on the natural warmth provided by the sun, while southfacing spaces are commonly reserved for rooms in the house that are rarely used ie the garage, or the kitchen which provides its own warmth through the use of oven’s etc.
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SCALE: 1:4,000
Hydrology
SCALE: 1:4,000
Hydrology is a major process occurring on site. There are several drainage catchments apparent on the land, as well as an intricate network of flow accumulation paths, and two larger stream environments which dominate the western side of the site. It is important to note flow accumulation detailed on the map. These paths are where water collects as shallow, transitory tributaries, which then flow down the sloping landscape into larger stream systems, and subsequently out into the Manukau Harbour. This natural accumulation and deposition of water into a wider water body is a significant process to take into consideration when developing a stormwater system to ultimately manage and clean water from all areas of the site.
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Noise Considerations
Puhinui’s close proximity to the Auckland International Airport creates noise issues which restrict how the area can be developed residentially. The red zone on the map indicates the path where aircraft noise will be the loudest, showing where we are unable to situate residential housing. Prospective commercial buildings can be constructed in this zone but are limited to an 8 metre maximum height restriction, and also require particular acustic insulation to ensure the outside noise level inside each building does not exceed 40 decibels when all windows and doors are closed.
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SCALE: 1:4,000
Viewshed
SCALE: 1:4,000
The basic viewshed analysis shows area’s of the land that are visible from an average person’s eye level, if they were standing in the centre of the site. Viewshed’s are generally important when it comes to deciding where to generate buildings, as preserving views of the natural landscape is an appealing apsect to any potential home buyer.
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Existing Vegetation
Existing vegetation on the site is predominantly open pastural land, with 2 small pockets of cropland apparent on the Eastern side protected by tall shetler belts. Due to the lack of development on the landscape thus far, the stream environments are not protected with native riparian planting, and there is currently no native bush or woodland in the area. Vegetative buffers will be necessary along the stream edges to protect and enhance the natural ecology of these spaces. Natural shelter belts like the ones shown in the aerial image would be ideal for the division of space on site between different proposed uses eg. commercial and agricultural zones.
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SCALE: 1:4,000
Masterplan The design has a strong focus on a small built footprint, with the intent of maximising three key elements of urban design: ecological corridors, land productivity, and a sense of community.
SCALE: 1:5,000
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1. Ecological Corridors: allowing ecological functionality of the Puhinui area through the retention of open reserve land and the revegetation of spaces where water naturally collects as a stream system - ultimately generating a green network throughout the landscape. The vegetated patches will be further connected through residential and street planting, forming corridors across the site which also branch out to the wider landscape, encouraging and protecting a biodiversity of indigenous wildlife inhabiting the area.
Stormwater Systems
Revegatation
Productive Land
2. Land Productivity: retaining and re-distributing parcels of agricultural land within the urban development strategy - continuing to maximise the land’s productive, arable soils. Urban agriculture is an important feature to consider for this project as Puhinui sites the last remanining agricultural area still within the city limits of Auckland, and a rising population will mean an increased need for sustainable and locally grown produce.
3. Sense of Community: creating an urban residential area that draws on a strong sense of community and social interaction. A close-knit community is a safe community, thus both high and medium density housing is designed to encourage the interaction of people. Small open spaces and a path network around the site also accentuate interaction and activity for the residents, with walkability of the site a key feature.
Public Open Space
Building Footprints
Circulation
Masterplan
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Circulation
The main road cross-axis sits in the centre of the site, for use by cars, pedestrains and cyclists alike. These main roads will have one lane leading in each direction, with the intention that only residents and visitors use the roads. Trucks and other industrial vehicles heading to or from the airport will be routed along Puhinui Road instead (north of the site), to avoid heavy flows of large vehicles passing through the neighbourhood. Local vehicular circulation is provided for by a road network which tries to minimise the road surface area in order to curtail the total impermeable surfaces on site. On-street carparking is available only along the main street by the retail hub, while all dwellings have their own off-street parking facilities to allow narrower road surfaces on subsidiary streets. Pedestrian and bicycle circulation is supported by a path network running along all the roads, as well as extended paths between residential plots that delivers access to open spaces and shortcuts to other streets, allowing easy walkabliltiy of the area. A boardwalk also ventures through a revegated ecological zone, providing a walking track through native bush for people to enjoy. 19
Building Footprints
The design is made up of a combination of building typologies (apartment blocks, courtyard terraced housing, single dwellings) which radiate out from the commercial/ retail centre as per the Multiple Nuclei Model. Apartment blocks are maximum 3 storey structures (to coincide with airport height restrictions) and are centred around the retail hub. There are two apartment blocks per 2000m2 plot, allwoing a total of 18 homes per plot as well as off-street parking for the residents. Garden courtyard terraced housing is also situated on 2000m2 plots, with a configuration of 10 houses per plot allowing a central, communial courtyard for mixed use by all the residents - creating smaller neighbouring communities within the wider community. Single dwellings are 350m2 plots, and are thus considered medium density housing. These dwellings are located furtherest from the commercial node, and back onto the vegetated ecological zones. Total development can support an estimated 1500 people. 20
Vegetation
Urban development occuring across Puhinui poses a serious threat to any exisitng ecological systems presently on site. It is important to preserve these ecological habitats from fragmentation, and where possible, to also enhance such areas to allow both flora and fauna to thrive. A 15m native vegetated riparian buffer surrounding each stream will provide a habitat for wildlife, as well as protect the water environments from contaminated urban runoff. Tree’s lining all of the roads as well as open public space will further connect the patches of ecological revegation on site - creating a strong network of green corridors for a diversity of ecologies apparent on site. Vegetation will all be native, in the form grasses, shurbs and broafleaf low land tree’s (ie. kahikatea, pohutukawa, karaka, nikau) to encourage native birds and insects to inhabit the area and help support the wider flora and fauna network through pollination.
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Hydrology
Stormwater on site will be managed through a series of Low Impact Urban Design installations which aid in mitigating the amount of urban pollutants in stormwater runoff before the water reaches the streams. Swales, raingardens and street trees planted along all road edging will help to filter road runoff. Buildings (especially commercial ones due to their siting on impermeable surfacing with carparking), will have green roofs to provide a permeable surface which catches and slows down water flow. Stormwater detention ponds along the streams will store water runoff from impermeable surfaces, and ultimately slow down flow into the streams. Stream edges will be properly buffered with a 15m native riparian planting scheme to further aid filtration and the cleansing of the urban runoff before it reaches wider water systems.
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Productive Land
Following up on merging agriculture with the urban fabric from the Phase1 Strategy, tracts of land have been retained for the continuation of intensive agricultural processes in the area. The preservation of Puhinui’s arable soils for food productivity ensures that the area becomes sustainable through providing locally grown produce for the community (and wider Auckland area), as well as ensuring that Puhinui’s historic productive character is maintained. The introdution of “urban agriculture’ (a form of permaculture) to the development will occur through pockets of land amongst the high denisty residential zone being set aside for communtiy gardens and orchards. This form of urban agriculture will encourage the community to get inolved in learning about sustainability and making connections to their environment, as well as providing an activity which will bring the commnunity together and create a strong sense of place for residents.
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Public Open Space
Public open space designed to service a neighbourhood is an important ammenity in any urban development - providing value to the areas people reside in. Several small open spaces have been reserved between each housing typology, to allow people an open green space for both active and passive use - promoting healthy recreational opportunitues. Open public space also encourages the interaction of people, helping to secure a connected community.
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References BACKGROUND INFORMATION AND STATISTICS: Auckland Unitary Plan, Auckland Council Document. Retrieved from http://www.aucklandcouncil.govt.nz
Harris and Ullman’s Multiple Nuclei Model. Retrieved from http://angelicaavila.weebly.com/multiple-nuclei-model.html
Urban Planning Theories and Models. Geofrey Yator. Retrieved from http://www.slideshare.net/bgeffa/urban-models-23134278
Neighbourhoods for Living: a guide for residential design in Leeds. Leeds City Council. (Dec 2003). PDF
Exploring New Housing Choices. Christchurch City Council. (n.d) PDF
Case Studies of Intensive Urban Residential Development Projects. Boffa Miskell. (2010) PDF
Designing an Urban Eco Village. The Nature of Cities. (2012). Retrieved from http://www.thenatureofcities.com/2013/06/30/ how-would-you-design-an-urban-eco-village/
The Native Plant Centre. Retrieved from http://www.nznativeplants.co.nz/shop/Native+Trees.html
Dense and Beautiful Stormwater Management. The Ped Shed. (May 2010). Retrieved from http://pedshed.net/?p=270
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