Long Bay, New Zealand
Background
Northwest Vaughans is an area of geologically demanding land within the Long Bay development under construction by client Long Bay Communities Limited. This portion of the development comprises two stages; a small high density zone on a narrow finger of land bound by a natural stream below and an escarpment above, and a larger lifestyle block zone situated on a broader ridge above the high density zone.
Scope
A number of previous consultants undertook investigations at the site during a protracted approved process. In addition, CMW undertook an intensive, targeted investigation, across the two areas, to prepare geological sections to model the proposed development.
Due to the highly faulted rock mass in this localised area, and the demanding zoning and access requirements for the site, a number of geotechnical remediation designs options were assessed for effectiveness, constructability, safety, consenting issues and costs. The adopted final design incorporated a range of solutions including formation of reinforced earth slopes, subsoil drainage networks, in-ground walls and key undercuts.
Findings/Challenges
Planning and design of the subdivision incorporated an intensive period of ongoing collaborative design between geotechnical requirements, civil requirements, land use yield and consenting requirements. As such CMW was required to update designs through several iterations and provide commentary to peer reviewers and Council to satisfy consenting requirements. Having staff competent with software such as AutoCAD Civil and SLIDE to quickly assess design changes and work alongside the civil consultants helped with this iterative process. Construction commenced in November 2016 with completion due by late 2018.