Dave Papworth Katherine Mante Sasha Verghese Raewyn Davie-Martin

PORT NIKAU

Port Nikau links the Whangarei City to the Harbour and beyond linking the outreaching district to Northland, Auckland and future growth to the future Port City at Marsden point.

HISTORY

CONTEXT POPULATION DENSITY

TOPOGRAPHY

HYDROLOGY

ECOLOGY

TRANSPORT

CASE STUDY

SUMMARY

REFERENCES

HISTORY

Manaia House Early Settler House Whangarei Heads

The Whangarei District is situated in the Eastern Region of Northland covering 270,000 hectares and includes the island groups Poor Knights, Hen and Chickens.At approximately 150 kilometres or two hours drive north of Auckland, Whangarei is the Commercial and Urban centre of Northland. South is the Portland Cement Works and Marsden Point with the Oil Refinery and is the site for further development for the Port for Whangarei and future urban expansion. The Whangarei Port supports a marine industry which has fluctuated in economic strength.Port Nikau is a Waterfront Development location on the Whangarei Harbour side basin a ‘central stage iconic position’. It is situated between the Whangarei Harbour, Onerahi to the North and Marsden Point in the South. The 106 Hectare development opportunity with deep water access has mixed use potential-commercial, retail, residential and industrial. Its is located in the middle of Central Whangarei Business Districtwith transport connections of arterial roads, rail, within reach of 3 airports. This premier location links the Whangarei city to the Harbour and beyond, linking to further parts of the Northland and Auckland regions.

Currently, the site is being considered in a planing process that is designed to add flexibility to the area, with a view towards providing amenities in keeping Whangarei’s 25-year growth predictions.This premier location links the Whangarei city to the Harbour and beyond, linking to further parts of the Northland and Auckland regions.

CONTEXT

POPULATION DENSITYMaori came in the first long boats in 950 B.C., tribal Ngapuhi and Te Parawhau. Early Settlers arrived in the mid 1800’s. Today, the Whangarei district has a population of 80,500. The urban centre has 52,500 people with surrounding coastal communities.

The District contains a high density of vegetation types that include Hikurangi Swamp, volcanic broad leaf forest remnants clothing scoria cones and soils, Pukenui Forest and Whangarei Harbour mangrove forests and estuarine tidal flats.

Grassland areas support rolling pastoral farmlands with beef, dairy and sheep farming being the main productive uses. There are productive horticultural blocks consisting of Avocado, sub-tropical and kiwifruit production. Soils within the rolling hill country consist of a variety of different types of clay and loam.

One of the most important features is the presence of volcanic broad leaf forest dominated by taraire, a nationally rare forest type.The native forest includes Podocarp broad leaf, Kauri and Kanuka patches, some of which are made up of forest.

Other nationally important vegetation types in the Ecological District are riverine forests, freshwater wetlands, and estuarine systems.

Areas within the district that have priority for protection include volcanic broad leaf forests, freshwater wetlands, riverine flood forests, estuarine systems, and areas of kiwi habitat, which are administered by the Department of Conservation, the Queen Elizabeth II National Trust and the Whangarei District Council.

Below Left: Shows the waters edge on the eastern edge of the site.

Below right: Shows the poor water quality in one of the man made swale on the edge of the road, located in the southern part of the site.

TOPOGRAPHY

Erosion on the coast will be affected by climate change. The expected tidal change will cause about .5m rise in the Sea level by 2100.100mm per year rise after 2100 is the expected height change after 2100. Erosion pressure on the coast will effect sand supply but sand replenishment by natural means may keep up with the erosion. Short term fluctuations on the shore line is expected to change the soft shore and dune stability of the outer coastal areas.

Climate change will affect the weather patterns. Storm events are expected to be more often so higher runoff levels in storm events will affect the water erosion caused silt,contamination of the waterways.Tsunami events although rare could see inundation of the southern reaches of our site. Tsunami could cause up to 3 meter surges on the southern tip of Port Nikau and this would have to be considered in our design.

SLOPE

Looking at the aspect of the site on a regional and catchment scale we can see that the surrounding hills have north, northwest, northeast slopes which are suitable to build on as you get great views of the city.

Most of the site is almost flat and the slightly elevated areas on the northern edges of our site have a Southern aspect. As it is a very minor slope facing south, it does negatively effect the building area as it actually works like a stage showcasing the amazing view of the harbour in the south.

This image illustrates the incredible southern views of Port Nikau Harbour.

ASPECT

The regional and catchment scale maps show the different zones of the greater Whangerei area. These include business, living, town basins, airport and Port Nikau zones.

On the GIS map of the site, it shows 2 main zones. The Business 4 zone and Port Nikau. Business 4 zone is classed as a heavy industrial area and Port Nikau is a marine area. The use of heavy machinery and nature of the current and historic industry’s impact on the land and waterways is very evident.

The site plan provided by PORT NIKAU Joint Venture shows the existing areas of land use.

ZONING

The regional and catchment scales shows that most of the land is classed as high and medium risk of being unstable in terms of development. The green coloured area indicated on the regional map shows the lowest risk of unstable land in the area and is where the majority of the built up area lies.

The majority of the site is reclaimed land. The coastal edge of the site is classed as high risk, this area includes man made rock sea walls, natural coastal mangrove /habitats. The core of the site is classed as medium risk and according to Orson from Reset Urban Design, the Geotechnical report found that as it was reclaimed so long ago, it is now stable enough for up to 6 story buildings.

SOIL INSTABILITY RISK

The site and surrounding area has been under treat from a number of different environmental factors. Being a industrial development has effected environmental conditions to which the site functions. Precipitation levels can vary greatly from season to season in Whangarei. The average precipitation is 1,490mm paThe tidal movement flushes the harbour and inlets naturally. The harbour waterways are clean until heavy rains wash contaminates into the water affecting ecological species. Contaminants are washed into the estuaries and inlets with storm water. They come from forestry, farming, fertilizer, sewerage spills, metals and biocides from the industry e.g. boating.

Work has been completed to upgrade the Sewerage plant at Whangarei Heads. This cleans and outputs grey water through Limeburner’s bay in a constructed cleansing system. Man made swales contribute to a natural management of wastewater and tidal fluctuations, which impose upon the land.Coastal flooding of the catchment and local coastal communities can be addressed by ensuring the finished floor levels are 2.5m above the ‘One Tree Point Datum Levels’. This will also mitigate any sea level rise up to 0.5m and spring tides/storm events. In the case of a Tsunami event local areas of up to 3 meters will be submerged.

HYDROLOGY

Recreational vessels north of site,mangrove fringe Northern waterway north,tidal wth mangroves,native vegetation

The purpose of the protected marine areas is to increase biodiversity and public awareness, whilst providing a ‘wet library’ for both study and recreation. These areas also look to complement and connect with existing land reserves that are already in place. They help protect and sustain the different habitats and channel areas that are evident within the harbour entrance.

MARINE MANAGEMENT

ECOLOGYThe Whangarei Ecological district is part of the Eastern Northland Ecological Region which is situated in the centre of Northland and includes the Whangarei Harbour.The greater Whangarei district consists of lifestyle and pastoralfarming, diverse horticultural blocks that include avocado, kiwifruitand sub tropical planting. The vegetation found in this district is veryrich and diverse, and includes a very significant sized volcanic broadleaf forest dominated commonly known as Taraire that is not foundin any other such large forest setting, anywhere else in the country. The Taraire tree has an form with large glossy dark leaves and large purple fruit in Autumn, which is an important food source for wood pigeons. Other important vegetation types in the districtInclude riverine forests, freshwater wetlands and estuarine systems.Estuaries in Northland grow and supply a wide range of food for birds and animals, fish and crustaceans. The main growth are being the marshes and mud flats this includes sedges, rushes, mangroves, bottom-dwelling algae, sea lettuce and eel grass.Northland has over 6300 hectares of mangroves and is spread over the 5 harbours, Rangaunu, Bay of Islands, Hokianga, Kaipara andWhangerei. Northland and Auckland are the only regions in new Zealand that have forests of large mangrove trees. There are over 70 species worldwide however NZ only has one, Avicennia marinaMangrove forests are crucial in Northland to its culture, heritage and survival of many native birds. Mangroves are protected in Northland, consent can be obtained from the council for the management of mangrove forests, especially when it comes to removal of seedlings in vital transport corridors or places of historical significance.

TRANSPORTATION Whangarei has a substantial transportation network that consist both of public and private uses. A railway line connects Auckland to Northland in and was established 1925 and mainly supports the commercial industry and burgeoning forestry .An arterial roading network provides links and connects parts of the region. The outcome of the development plan looks to create accessibility through providing an efficient roading network with provision for alternate modes of transport in relation to the councils strategy and direction.Three Domestic airports with the closest at Onerahi just 10 minutes away by vehicle.Sea access provides links to Marsden Point, Tourism in Northland, Recreational opportunities and further access links to the Airport at Onerahi.

New Bridge north of Port Nikau- under construction

Railway line through site

Site wharf site-existing

Poplars,Mangroves,Pampas,Grasses with Exotic Cypress Hedge on site

Sea level rise/ tsunami risk

The sea level is projected to rise by .55 meters by 2079

Victoria Dockside, Australia.A sustainable sewerage system, self sufficient to the site. The system is buried underground.A composter system of worms and beetles digest the waste from the sewerage, thus no sludge is produced. Water is not necessary in this environment and any produced from the waste/grey water is treated and reused on site in the public toilets or garden irrigation etc thus no waste water is sent into the wetlands.

Rainwater can be used on site, collected for drinking, household use and connected a drainage network, reducing waste water out flow

Conclusion A sustainable ecologically designed compost system can be used at a small or large city scale. Sewerage, a soil fertility adjunct can be a resource, along with rainwater catchment can be an efficient use of resources for sustainability.

CASE STUDY

Whangarei Sewerage Treatment Plant

‘A hub that takes advantage of Northland’s moderate climate, relaxed lifestyle whilst addressing environmental conditions and allowing for a commercial return.’ The Future outlook is for a mixed use development that provides a major focus for the growth of Whangarei and its Business District.This premier location links the Whangarei City to the Harbour and beyond, linking this region to other parts of Northland and Auckland as a Satellite city.

SUMMARY

REFERENCESWebsites:http://www.wdc.govt.nz/Pages/Default.aspxhttp://www.doc.govt.nz/parks-and-recreation/places-to-visit/northland/kaitaia-area/te-paki/features/natural-features/http://www.nrc.govt.nz/For-Schools/School-information-packs/Estuaries/https://www.niwa.co.nz/our-science/coasts/research-projects/restoration-of-seagrass-beds-in-whangarei-harbourhttp://www.nrc.govt.nz/Resource-Library-Summary/Research-and-reports/Coastal/Seagrass-in-Whangarei-Harbour/www.greengeek.ca/on site treatment-at-new-green victoria-developmentwww.urbanhotels.com/blog/sewage-system-set-to-green-htmlwww.china.org.cn/environment/2011-03/16/content_2215500.htmwww.sustainablebuild.co.uk/sustainabledesignsewage.htmwww.nzgeographic.co.nzwww.doc.govt.nzwww.whangareinz.comen.wikipedia.org/wiki/Whangareiwww.wdc.govt.nzwww.localcouncils.govt.nzwww.wdc.govt.nzbb.blogspot.comaucklandcity.govt.nz111.emergency.co.nzHerb Kane Print www.floistudios.comCoastal Erosion Hazard Zone review,Whangarei District Council

PDF’s from websites:Niwa Taiaro Nukuarangi, Numerical Modelling of Tsunami Inundation, Northland Regional Council 2007State of the Enironment Report: Whangarei District Plan -Part D-Environment Rules-Port Nikau tenix brochure (port nikau)Feasibility study to investigate the replenishment/reinstatement of seagrass beds in Whangarei Harbour – Phase 1_upload_3108_Feasibility study for the replenishment of seagrass in the Whangarei Harbour - Phase 1.pdfBiodiversity values and opportunities for restoration at whangarei heads whangarei_hds_restoration_plan_0.pdf50-Port-Nikau-Environment.pdf