Deep Gravity Sewers Study

Project Title	Environmental study for the proposed Deep Gravity Sewers project at Sentosa
Project Description	An Environmental Study was commissioned by Sentosa Development Corporation (SDC) in July 2020 for the proposed Deep Gravity Sewers project at Sentosa (hereinafter referred to as the “Project”). This Project would involve the implementation of a pure gravitational Deep Gravity Sewers (hereinafter referred to as “DGS”) system on Sentosa to replace the island’s existing aging sewer network. The DGS system would be more efficient, reliable, and sustainable as a long-term solution for the next 100 years, in line with PUB’s implementation of the Deep Tunnel Sewerage System (DTSS).
Project Site Information
Environmental Study Summary	Following a preliminary assessment on the entire proposed DGS system, it was discussed with Technical Agencies that the key focus of the Environmental Study would be for above-ground construction worksites near identified Nature Areas (i.e., Mount Imbiah and Mount Serapong), as there would unlikely be environmental impacts during its underground operations. The summary of impact significance (with minimum controls) and the potential residual impact significance (after considering mitigation measures for moderate and major impact significance) for the construction phase are presented in the following table. A construction phase Environmental Monitoring and Management Plan (EMMP) was proposed to (1) ensure that any potential impacts arising from the project are within anticipated levels and (2) assess the effectiveness of the recommended minimum control measures and site mitigation measures in reducing identified environmental related impacts on key receptors. The EMMP will monitor construction activities and ensure appropriate monitoring and management procedures are in place. Further details can be found in the associated reports from the Environmental Study.
Environmental Study Report	(link to PDF)/place the PDF icon of the Summary, Environmental Study Report, Technical Note
Stakeholders Consulted	Relevant business establishments in Sentosa
Publication Date	17 February 2022
Feedback	This EIA report is open for feedback until 17 March 2022. We welcome your feedback at sustainability@sentosa.com.sg