The scope of works included open trenching along the existing wastewater main to remove the existing 150mm Earthenware pipe and replace with a new 225mm PVC main. Mainline installation depths varied between 1.0 to 2.5m below ground level, with the ground conditions requiring the use of trench shield and dewatering.

Specialist subcontractors were engaged to replace the residential lateral connections using pipe bursting, minimising the disruption to residents, pedestrians and existing pavement infrastructure. A niche component of the project involved the replacement of the existing wastewater line which passes through a large (1350 diameter) Stormwater structure in 2 locations. This required removing the existing concrete pipework and installing new steel casings to accommodate the new PVC main. Hunter Civil completed all the open trenching, new mainline installation (including casings through stormwater structures), dewatering activities and Traffic management for the project.This project required extensive stakeholder and resident communication, particularly as a portion of the works directly affected the access to Westfield Riccarton Mall, necessitating coordination to minimise impacts on businesses and the public.

Hunter Civils engaged with residents and key stakeholders early on to understand their requirements, adjusting the Traffic management plans and sequencing of works to minimise the overall impact of the project.