BG&E was engaged by the Department of Planning and Environment to conduct a thorough structural condition assessment of Catherine Hill Bay Jetty. The current concrete and steel structure, erected in 1974 to replace the historic timber jetty, has suffered neglect since 2009 when mining operations ceased. This assessment had two primary goals: evaluating adaptive reuse possibilities and considering demolition options.

BG&E, in collaboration with subcontractors, conducted a comprehensive structural engineering and durability assessment.

This work involved extensive on-site works including

• Conducting reality modelling and high- resolution imaging via UAV.
• Cleaning of steel piles in the tidal zone.
• Thickness testing of steel elements.
• Strength and integrity testing of concrete elements.

Following the on-site data collection phase, extensive structural engineering modelling and calculations were undertaken to determine the current load capacity of the jetty and whether strengthening was required. Durability modelling, to determine if there was any remaining life of structural elements, was also conducted.

Three options were explored in this assessment

1. Partial demolition over the land portion: based on the initial high- risk report, this option involved demolishing the heavily deteriorated landside jetty while retaining and maintaining the over-water portion.
2. Full demolition to the seabed: this option considered the complete removal of the jetty in manageable sections, utilising both landside and marine equipment.
3. Rectification of the full jetty: this extensive option involved the comprehensive remediation of both land and over-sea portions, including the demolition and replacement of various steel elements, such as landside columns, secondary steel framing, bracing, and multiple connections.

This structural assessment was delivered in 2023.