The client

Cashmere Park Limited is a family run company owned by a local structural and civil engineer, Warren and his wife, Marrianne Lewis. Warren approached us in 2018 to assist with developing farmland located in Cashmere, Christchurch and owned for over 30 years into a bespoke residential subdivision. The company, Cashmere Park Ltd construct architecturally designed homes complete with landscaping ready to present to the open market for purchase. Keeping within the family, Warren’s son, Steve Lewis is the Construction Manager. The small team comprises of further family members, and employs a Site Foreman, two carpenters and construction support.

The development forms part of the regional new neighbourhood area development with a specified density of 15 lots per hectare. The sections range in size from 400sm – 550sm.

The challenge

The site, with wet, soft ground, posed challenges with stormwater management namely the retention and treatment of stormwater. Additionally, the water table was higher than predicted meaning some plant species selected for the extensive wetland planting would not be suitable.

Eliot Sinclair provided services throughout the entire process from consenting, design, and construction to the cadastral surveying for the issuing of titles.

The solution

We worked with our client to develop concept plans for the site including the subdivision layout and road design, reserve areas and the size of the allotments. Engineered drawings were then prepared to show the construction of the new roads and services, including stormwater management, high pressure water, and utilities. Box drains on the site were removed and replaced to ensure adequate drainage.

Detailed designs with the street tree plan and planting design were drawn. Our three waters engineers created stormwater modelling and we designed the stormwater management areas in shapes that would adequately handle the water run-off. One of the basins was designed with pools at different heights to reflect the variable water level and a separate stormwater treatment area was included.

Tree pits, high in clay soil and slow to drain, were turned into large water containers. We adjusted the selection of tress to be planted to species that could handle the conditions sufficiently.

Once the plans were approved by Council and the contractors had been selected by our client, we ran the construction contract through to the completion of the project. We completed cadastral surveys of the site for the titles to be issued.

Our client is offering design and build packages and managing the construction themselves. Each stage of the development is being subdivided separately with 5-6 lots being released at a time as the construction is completed. This is a unique way for us to work through the subdivision process, and we will work with our client to provide the cadastral surveying for each stage only as and when it is needed.

The recreational reserve on the site is adjacent to a council owned reserve. During the process of planning the site layout, the council was encouraged to reinvigorate the adjacent reserve at the same time as the development. Our design of the recreational reserve positively informed the redesign of the existing reserve.

Despite a challenging site with difficult ground conditions, we provided our client good design that minimised the amount of filling required onsite, reducing construction costs. The close collaboration between our teams ensured a streamlined process, with quick decision making.

Client
  • Cashmere Park Ltd.
Services
  • Land surveying
  • Landscape architecture
  • Urban design
  • Three waters engineering
  • Civil engineering
  • Planning
  • Geotechnical engineering
  • Environmental science

View the full project video.