While all projects tell a story, some projects have a longer, more complex tale than others. The existing dwelling at Crest Lane was demolished after the 2011 earthquake. HGM joined the story in 2020 in a subcontract capacity to Morel Construction after an insurance rebuild attempt failed. HGM were engaged to provide design and methodology input on remedying the deficient work completed previously and completing the necessary slope retention work required to enable the build to proceed. Eventually, after a 2 year process, designs were finalised and approvals were given to proceed with the project. HGM were then engaged to carry out the physical work which included:
- Anchoring and installation of whalers to support the neighbours existing retaining wall above prior to excavation for the retaining walls.
- Removal of existing sub-par retaining walls and remediation of ground including engineered backfill
- Construction of 11 retaining walls in total over the site including one consisting of 6 x 600 dia holes 5.5m deep with pile cages and multiple timber pole walls.
- Excavation of steep slope behind the house and installation of temporary works anchors and matting to enable access to work below.
- Drainage installation, back filling and topsoiling behind retaining walls. Application of hydro seed.
The project presented significant technical and logistical challenges. The steep slope and proximity to the neighbouring property posed significant challenges which resulted in the requirement for stabilisation of the neighbours existing retaining wall before work could commence. At the same time, work was required in close proximity to the existing rebuilt dwelling while extensive repairs where being undertaken.
The complexity of the site demanded a carefully sequenced construction programme, with many stages dependent on the successful completion and verification of the previous one. Maintaining safety, minimising ground movement and ensuring engineering compliance were critical throughout the project. Throughout construction, ongoing monitoring of neighbouring structures and ground movement ensured that works progressed safely and in accordance with the project design requirements.
Through collaborative planning, technical expertise and precise execution, HGM successfully delivered all ground retention and enabling works, providing a stable platform for the residential rebuild to proceed.
After years of uncertainty and complex engineering challenges, the successful completion of these works marked a significant milestone, allowing the rebuild to continue and helping bring a long and challenging chapter to a close for the homeowners.
