Puhinui Phase 2
Puhinui Ecolgical Connection
MISSION STATEMENT Merging agricultural processes within an urban fabrication: retaining the landâ€™s sustainability and ecological values of Puhinui whilst providing urban space for the rising Auckland population.
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 Phase 2 Development Strategy
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.
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 siteâ€™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.
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
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.
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. Aucklandâ€™s current CBD). The idea behind this is to create areas of different activities that are appropriate to each othersâ€™ 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
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-byâ€™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 Mangereâ€™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 areaâ€™s.
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.
Site in context with the proposed design strategy
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.
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.
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 areaâ€™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 ovenâ€™s etc.
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.
Puhinuiâ€™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.
Development on slopes of >15o can result in high erosion rates and the compound sedimentation of waterways, and should thus be avoided when planning a suburban subdivision. As the map illustrates in red, these steeper slopes are predominantly along the coastal edge and upper tributaries of streams on site â€“ providing a potential for the revegetation and enhancement of riparian edges whilst protecting the steep land from intense urban development. The rest of the Puhinui landscape largely sits at <4o, a gentle slope rendering the land suitable for both urban housing developments and agricultural processes.
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.
Phase 2: Puhinui Ecological Connection To enhance community connection and interaction with Ecology.
Puhinui Ecological Connection
The design driver was to follow the previous concept of multiple nuclei method, where urban development based on planning cities around multiple nodes of activity, rather than sprawling out from one focal point. This idea emulates the multiple nuclei method, except by basing urban development around of points of significance on site, such as ecological landmarks and transport networks. The focus was to enhance ecological functionality through re vegetation of water flows on site and a central core of bush where these small patches of vegetation are linked. A design that is ecologically driven, that will maintain green space for flora and fauna. Housing typologies include medium density standalone buildings, and high density apartment blocks which are surrounded by large areas of open green space, retaining the rural character of Puhinui. Residential areas are well connected through central pathways, giving easy access to transport networks and ecological areas, encouraging the use of public transport.
Puhinui Ecological Connection
Open Green Space 18
The land had minimal vegetation, prominent in rural flat areas of land, with very few shelter belts scattered along the site. The planting scheme was to vegetate areas that had high water flow, which had been identified in the flow accumulation data from gis, to create natural native forest across the site that is ecologically functional and a natural aesthetic. Planting in these water flows and stream areas include Native grasses and broadleaf mixes that can deal with both extreme wet/dry conditions. Street trees have been planted on the main axis giving queues for visitors that they are entering the settlement.
Native Forest & Wetlands Large Street Trees
The building footprint area is relatively small, to preserve as much open space to retain the rural character of Puhinui. A simplistic approach, utilizing two housing typologies, this included high-density 2-story apartment style buildings that are approximately 20 x 15m. Medium Density housing is more privatized, with a large sections single story with an area of 20 x 30m.
Commercial High Density Medium Density
This Productive land will be utilized for horticultural and agricultural mixed use. This area was selected for its high land use capability, indicating ideal soils for production.
Existing green space that has been preserved for its ecological values. There are specifically ecologically sensitive streams areas that have been avoided of any urban development to retain these ecological values and Puhinuiâ€™s rural character. Corridors of courtyard spaces, which will be mixed use, are linked via pathways allowing access from all areas of the subdivision.
Circulation The circulation consists of a single main road and two intersecting main roads that form join multiple shared roads that connect perindicular to the main arterial road where the transport hub and commercial areas are located. The shared pathways primarily run across inbetween sections of high density areas and acts as a link connecting the wider community to the central transport hub.
Transport Hub Shared Roads Shared Pathways Arterial Roads