Project Overview

Siding Springs Observatory is located on the edge of the Warrumbungle National Park near Coonabarabran, NSW. The facility is the largest optical observatory in Australia and is an important site for astronomy, astrophysics and space science.

The main access road to the observatory was significantly deteriorated and had subsided following an intensive storm event, raising safety concerns of further landslip. Complex was engaged to remediate the site, constructing gabion retaining walls up to 3.5m high, concrete lined stormwater drainage and full depth asphalt pavement.

The works involved significant cutting in high strength basalt bedrock materials adjacent to steep batters. Multiple large trees were cleared for construction of the gabion retaining wall with strict environmental considerations within the National Park. On completion of the retaining wall, guardrail was installed and the road widened and pavement reconstructed.

All works were undertaken to allow the roadway to be trafficable outside of working hours and in the event of an emergency. Complex completed the works ahead of the proposed delivery timeframe without any safety, environmental or quality incidents.

Project Features

• Remote works with restricted communications
• Coordination with major stakeholders
• Extensive clearing of trees and shrubs
• Demolition of existing road pavements
• Excavation in rock to form profile for gabion wall
• Installation of gabion wall up to 3.5m
• Placement of engineered fill
• Reinstatement of flexible pavement
• Traffic Control Devices
• Installation of guard rail
• Landscape rehabilitation