Ngau Tam Mei Water Treatment Works

Opened in 2000, the Ngau Tam Mei Water Treatment Works stands as a testament to Hong Kong’s innovative approach to water management. This facility, nestled in Ngau Tam Mei, delivers treated water to Yuen Long, Tin Shui Wai, Ngau Tam Mei, and Mai Po. It boasts an impressive output of 230,000 cubic meters of treated water per day. The Ngau Tam Mei Water Treatment Works was the first in Hong Kong to utilize granular activated carbon biological filters enhanced by ozonation. This advanced technology allows for a more efficient and effective treatment process. The journey of water here begins far upstream in the Dongjiang River of Guangdong. The raw water undergoes a fascinating transformation at the Ngau Tam Mei Water Treatment Works. First, pre-ozone contact tanks oxidize impurities, control algae growth, and eliminate unwanted tastes and odors. Then, a mix of hydrated lime and alum is added in rapid mix tanks, causing impurities to coagulate. These larger particles settle as sludge in triple-deck sedimentation basins. This sludge is then collected and transferred to a thickening tank for further processing. The now clarified water then proceeds to intermediate ozone contact tanks for further oxidation and disinfection. Dissolved oxygen is enriched, prepping the water for its next stage. Gravity then pulls the water through dual media filters. These filters meticulously remove fine particles before it enters biological filters containing granular activated carbon. Here, with the help of added nutrients, ammonia and organic matter are biologically removed. The final step involves dosing the water with chlorine and hydrated lime in contact tanks for final disinfection and alkalinity adjustment. This protects the water from corrosion as it travels through pipes. The now purified water is stored in clear water tanks before being pumped to the primary service reservoir, ready for distribution. In 2001, the innovative design of the Ngau Tam Mei Water Treatment Works earned a prestigious award from the American Academy of Environmental Engineers. This award recognized its groundbreaking use of dual-stage filtration and ozone disinfection, a safer alternative to break-point chlorination. So, as you stand before this unassuming facility, remember the intricate processes happening within. The Ngau Tam Mei Water Treatment Works represents more than just clean water. It represents ingenuity, forward-thinking design, and the constant pursuit of providing a vital resource to the community.