Harakeke Heights

Summary

• Harakeke Heights is a major residential development on the Kāpiti Coast, encompassing the Ti Kouka and Homestead Dunes Neighbourhoods in the Ngārara Zone area.
• Covering around 33 hectares and providing approximately 450 lots, it sits amid high-value ecological areas, such as natural wetlands, dunes, and other open spaces rich in wildlife.  
• Awa Environmental was project manager for the concept design and consenting phase, working alongside development manager, Devcorp.
• In this lead role we integrated RMA planning, civil and stormwater engineering, and flood modelling to design the foundations of the development.  
• Supported by specialist subconsultants, we guided the project to a major consenting milestone, with a design that maximises value for all parties.
• Stages 1 and 2 of the Ti Kouka Neighbourhood are fully consented and “shovel ready”, with regional council, land use, and subdivision consents in place.  
• The Greater Wellington Regional Council has granted earthworks and stormwater consents for the whole development.

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Challenges

• For private developers, maximising financial return from a residential development is a central challenge.  
• At Harakeke Heights, this goal intersected with broader objectives shared by multiple stakeholders, including Te Āti Awa o Rongotai, Kāpiti Coast District Council, Greater Wellington Regional Council, the QEII National Trust, future residents, and the wider Kāpiti Coast community.  
• Beyond financial return, the project needed to:  
  
  • Protect and enhance ecological values  
  • Manage flood risk and water infrastructure demand
  • Create a sustainable, thriving community.  
• Some of these goals are prescribed by regulations and public plans and baked into the consenting process.  
• In relation to stormwater management, the Ngārara Development area plan required a low-impact design with a water treatment component, and on-site runoff retention.  
• Additionally, a QEII covenant over significant wetlands on site and adjacent meant that the design need to support their protection and regeneration.  

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Solutions

Project and Design Management  

• Since mid-2022, Awa Environmental has managed the project, coordinating and collaborating closely with specialist subconsultants, including planners, urban designers, ecologists, geotech engineers, and groundwater experts.  
• We also led consultation with Te Āti Awa o Rongotai iwi on the development design.

Civil and Stormwater Engineering Design & RMA Planning

• Awa Environmental delivered the full engineering design for resource consent, encompassing three waters, roading, earthworks, walkways, parks, access around wetlands, and other elements.  
• This overall civil design enhances development value while upholding RMA, district plan, regional plan, and QEII covenant principles, meeting stakeholder goals, and allowing for future challenges such as climate change.  
• A central way it does this is through an innovative, integrated stormwater system and earthworks design.  
• The latter raises the ground level to enable the wetland groundwater to “breathe” as it fluctuates.  
• The stormwater system leverages the natural benefits of well-drained sandy soils to minimise the impacts of runoff and keep it onsite, reducing reliance on the public network.  
• Solutions include open spaces for stormwater storage and drainage via low maintenance biofiltration techniques: vegetated swales, bioretention swales, and rain gardens.  
• These integrate with public infrastructure, such as roads, footpaths, and playgrounds, and will capture, convey, treat, and infiltrate stormwater runoff.  
• Other system features include:
  
  • Overland flow paths to direct runoff away from houses
  • Narrower streets to reduce impervious areas  
  • Rain tanks and soak pits on private sections, preventing dwellings from discharging directly into the wider drainage system during high- to medium-frequency storms
  • A well-positioned, low-impact bridge linking the Ti Kouka and Homestead neighbourhoods.  
• In a first for Greater Wellington and among the first in New Zealand, consent was granted under the National Environmental Standard for Freshwater Management for the removal of newly formed wetlands.  
• The design integrated the development with the natural ecology of the site, and the removal of these wetlands was managed through the proposed establishment of new, larger areas of wetland protected under the QEII covenant.  

Flood Modelling

• Flood modelling was integral to engineering design and consenting.  
• Our modelling specialists provided flood risk assessments, flood hazard mapping, and stormwater quality engineering assessments, which fed into the design.  
• Notably, proposed earthworks were added to the model to demonstrate the design had less than minor effects.  

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Benefits

Integrated outcomes

• Awa Environmental’s integrated planning, engineering design, and modelling, alongside close collaboration with others, produced a concept design that maximises value for all parties - balancing financial return with ecological protection, cultural values, and community wellbeing.
• For councils and iwi, the design supports their long-term visions for their respective communities and the environment.
• Future residents will enjoy enhanced built and natural environments, with high-value open spaces and ecological resources at their doorstep.  
• The design safeguards wetlands, improves water quality, and creates new habitats.
• It also provides redundancy for climate change, which is important for this low-lying coastal area.

Stormwater system advantages

• The innovative stormwater design reduces upstream and downstream flood risks, lowering potential damage, clean-up and rebuild costs, and insurance premiums.
• The low-impact design delivers lower construction and maintenance costs compared to traditional stormwater network and treatment solutions.  

Water efficiency

• Our water efficiency experts showed that 4,500L tanks, rather than the prescribed 10,000L tanks, were sufficient to meet District Council goals of reducing potable water demand by 40%.  
• This reduced future development costs while meeting a key goal of an important stakeholder.  
• For residents, the result is improved water efficiency and lower bills.  

Working with Awa

• The client benefited from a single trusted partner managing the complexities of the project.  
• Our predominantly senior staff delivered with responsiveness, adaptability, and technical excellence, ensuring critical consenting milestones were achieved efficiently.  

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