Yuen Long Effluent Polishing Plant

The existing Yuen Long Sewage Treatment Works (YLSTW), constructed in the mid-1980s, is a secondary sewage treatment plant in Hong Kong that has been providing treatment for the Yuen Long Industrial Estate and parts of Yuen Long town for over 30 years. Commissioned by the Drainage Services Department of the HKSAR Government to cope with increasing demands from the growing population, we upgraded the treatment capacity of YLSTW from 70,000 cubic metres (m³) per day at secondary sewage treatment level to 150,000 cubic metres (m³) per day.  Meanwhile, to realize the Government’s and our commitment to decarbonization, we designed the new facilities to maximize the use of renewable energy and strive towards energy and carbon neutrality. 

Going green with renewable energy and green technology for environmental sustainability

While turning the biogas harvested from the treatment process into electrical energy for its daily operations, YLEPP is the first wastewater treatment plant in the city to adopt aerobic granular sludge (AGS) process for biological treatment, which demands less energy while improving efficiency.

Having over 5,000 monocrystalline-type PV panels on most of its roofs to generate solar energy, the buildings of YLEPP also include skylights and solar pipes to bring in more natural lighting.  Lastly, treated sewage effluent will be reused for cooling to lower energy and water demand.

Integrates public areas to promote community engagement

Besides its environment features, a part of the site will be transformed into a public co-use area to better engage the community.  An education corridor will provide visitors with information about sewage treatment and renewable energy, while a roof garden with bird hide provides a relaxing open area for visitors to rest and enjoy.

Our work for YLEPP includes investigation study, preliminary and detailed design, impact assessments on the environment, drainage, geotechnical, traffic and other aspects, and associated site investigation works and supervision. We also facilitate public engagement and consultation with relevant stakeholders; and assist the client in the preparation of tender documents, assessment of tenders, contract administration and construction supervision.