The WSD retained CDM to study, design, procure, supervise construction, and commission the 230 million liters/day (MLD) Ngau Tam Mei water treatment works. The HK$1.8 billion (US$227 million) project is the first water treatment plant worldwide to use dual-stage biological filtration with granular activated carbon to remove ammonia-replacing break-point chlorination-and will treat wastewater-contaminated raw water from the Dongjiang River. Ozone provides pre-oxidation and primary disinfection.
CDM conducted a 14-month pilot study to confirm design criteria and optimize overall processes, and collaborated with the WSD to implement a comprehensive solution tailored to client needs while meeting long-term environmental goals. The facility makes optimal and aesthetic use of limited site through a compact modular layout—the triple-deck sedimentation tank reduces land use by 60 percent, incorporates a SCADA system to reduce labor costs and improve plant management, and is expandable to 450 MLD.
This project won the Superior Achievement Award from the American Academy of Environmental Engineers in 2001.
CLIENT: Water Supplies District
LOCATION: Hong Kong