NSW Office of Environment and Heritage (OEH)
Sydney Harbour National Park, Watsons Bay, NSW

Geotechnical walkover assessment & investigation.

JK Geotechnics completed an assessment of the risks associated with potential cliff face instability and the impacts on the proposed walking track upgrades and existing heritage structures.

Project challenges

Two of the major constraints to the proposed cliff-top walking track upgrade were a number of overhangs immediately below the cliff-top crest and large areas of ‘floaters’ (detached blocks of sandstone) along sections of the cliff-top crest, which posed a significant threat to the stability of existing heritage military structures and the Hornby Lighthouse.

Our solutions

JK Geotechnics completed risk assessments and analyses of engineering geological factors impacting on the existing structures and sections of the proposed walking track. We identified appropriate set-back distances from the cliff top for the walking track and identified the heritage structures that were unsuitable for inclusion in the upgrade works due to stability concerns.