As a result of extreme wet weather that impacted the Northern Rivers of NSW in February 2022, three landslips occurred on the riverbanks immediately downslope of the 200ML off-stream storage dam, and facility sludge ponds. With concerns of landslip regression resulting in damage to Kyogle water storage facility, LRC Geotechnical were engaged to complete geotechnical analysis and design for the remediation of the landslip sites. Through collaboration with Public Works, Aldersons Associate and Kyogle Council and with consideration of environmental impacts, construction access and existing site infrastructure, a permanent remediation design of landslips through a combination of tiered MassBloc Graviti TM walls with a porous rock engineering backfill was adopted. Analysis a design to remove and relocate the existing sludge ponds away from the slip site was also designed. The ‘for construction’ design was issued in November 2025. The upgrade works are currently package for tender submission and should commence in 2026. The geotechnical services provided for the project include: Interpretation of existing geotechnical reports, survey and investigations results to develop geotechnical models of each landslip site. Geotechnical analysis including back analysis to determine slip causation and current FoS of the Richmond riverbank at various locations within the impoundment facility. Geotechnical analyses using limit equilibrium and finite element analysis to inform (30%, 80% and 100%) design development. Geotechnical stability analysis of construction stages, including construction of access roads, use of cranes, as well as removal and relocation of the existing sludge ponds. Input into safety and design reports and construction staging. Preparation of construction documentation and project specifications. Construction supervision and hold point inspections (on-going).