In face of an increasing demand of land resource, the Hong Kong SAR government has been exploring different options of increasing land supply in Hong Kong. Rock cavern development is considered as one of the new sources of land supply. By relocating suitable government facilities to caverns, the original land as well as adjacent land can be released for other purposes.

AECOM was commissioned by the Drainage Services Department of Hong Kong  Special Administrative Region Government to conduct a feasibility study for relocating Sha Tin Sewage Treatment Works (STSTW) to caverns, which is the first  and foremost cavern study being carried out under this new  initiative.

With the daily capacity of 340,000 cubic meters, STSTW is the largest secondary sewage treatment works in Hong Kong, serving nearly a million people. AECOM investigated the suitability and technical feasibility of Nui Po Shan of A Kung Kok as the cavern site.
AECOM’s scope of works included preliminary technical and impact assessments, ground investigation, preparation of an outline design for the engineering works, formulation of implementation strategies and programmes, and public engagement. It also involved a planning review of the future land use of the existing STSTW for the purpose of establishing a business case for the relocation project. Meanwhile, AECOM’s geotechnical team was responsible for assessment and design development of the tunnel, cavern, foundation, slope and landslide hazard mitigation elements of the project.

The relocation project would be able to release about 28-hectare area of land for housing and other purposes that would enhance the living quality of the public and bring extended benefits to community and environment of Sha Tin.
With the innovative public engagement approach – “Experiential, Multi-platform and Iconic”, we have successfully helped the public and related stakeholders to understand more about the project and this project was named as the winner in the Marketing and Communications category in the 2014 International Water Association Global Project Innovation Awards competition.


  • International Exhibition of Inventions of Geneva – Silver medal – Resident Site Robotic Supervisor (RSRS)
  • Construction Sites Safety and Housekeeping Award Scheme (2020) – The Best Construction Sites Safety and Housekeeping Awards, Cat. (a) – Large scale civil works contracts (contract sum > $500M)
  • Construction Sites Safety and Housekeeping Award Scheme (2020) – The Grand Award
  • The Institution of Civil Engineers (ICE) Awards 2021 – Edmund Hambly Medal Winner
  • 26th Considerate Contractors Site Award Scheme (CCSAS) Award – Considerate Contractors Site Awards (CCSA) , Gold
  • 26th Considerate Contractors Site Award Scheme (CCSAS) Award – Outstanding Environmental Management and Performance Awards (OEMPA), Gold
  • 2020 CIC BIM Achievement – BIM Projects