Issue 04, Oct 2020

First Deployment of UV Disinfection Technology to Water Treatment Plant

A joint venture formed by ATAL Engineering Limited and Chun Wo – Ming Hing had won a contract from the Water Supplies Department, for in-situ reprovisioning of Sha Tin Water Treatment Works (STWTW) (South Works) – water treatment works and ancillary facilities. Representing the first water treatment plant by Water Supplies Department to deploy ultraviolet (UV) disinfection technology with total contract sum estimated at HK$4.5 billion, the project is due for completion in 2026.

ATAL is engaged in the design, build, testing and commissioning of all electrical and mechanical works. As the South Works has been in service for some 50 years, we will provide in-situ reprovisioning of water treatment process units featuring the latest technologies, such as lamellar sedimentation, two-stage filtration, ozonation, disinfection by UV light. When the new treatment works commence operation, it will be able to cope with increasing water demand arising from new housing developments in parts of Kowloon, Central and Western District on Hong Kong Island and Sha Tin District.

Over the years, ATAL has been striving for innovative solutions that can be implemented at its projects in order to achieve the best results. Traditional water treatment disinfection relies on chlorination. For the South Works of STWTW, a new approach will be adopted, i.e. ozone and UV plus traditional chlorination to achieve four-log disinfection. This new approach provides swift and effective inactivation of viruses and pathogens, making them incapable of reproduction and infection. The new disinfection technology, with high virus and pathogen inactivation rate of 99.99% across major process treatment lines, will go towards assuring water quality.

“We are excited to have won the contract which is a testament to our leading position in the environmental sector. The South Works provides the opportunities to demonstrate our continual development and adoption of the latest technologies to maintain the highest water quality standard, especially with rising hygiene awareness in the wake of COVID-19. It is our pleasure to participate in this significant project, which allows us to uphold our motto ‘We commit, we perform, we deliver’ while bringing better quality of life to the city,” said Mr Raymond Chan, Executive Director and Managing Director of ATAL Engineering Group.

The awarded contract belongs to the second phase of the reprovisioning of the South Works of STWTW. Phase one included site formation for administration building, construction of a logistics centre, hydropower plant, access roads and reprovisioning of power house which was completed early 2020 and ATAL was responsible for the design and construction of the E&M plant. The current phase two includes construction of residual management facility, South Works pumping station and treatment processing units, site formation for remaining works, construction of new access roads and improvement to existing access road.

Left: Aerial view of Sha Tin Water Treatment Works

Right: Contract signing ceremony

Tapping Technologies for Water Safety in the City
引入新技術 提升本港水質

Clean water is one of the essentials of life. It is the reason why we consider water treatment as an important social responsibility. ATAL employs highly effective water treatment processes, including coagulation and flocculation, pH adjustment, sedimentation, rapid gravity filtration, onsite chlorine generation, ultraviolet disinfection, ozonation and sludge treatment to ensure that only the best quality of water will be served.

A testament to our success and expertise in water treatment, as well as wealth of experience in potable water and sewage treatment, are the numerous projects entrusted with ATAL over the years, ranging from design and construction of water treatment facilities to pumping stations and seawater treatment systems. Our contributions to the advancement of water treatment works (WTW) can be found in both Hong Kong and mainland China. The former includes the Ngau Tam Mei WTW, Tai Po WTW and Ma On Shan WTW, while the latter includes the Shandong Weihai WTW, Jilin Changchun No. 5 WTW, Hebei Tangshan WTW and Hunan Hengyang WTW.

Among the Group’s recent accomplishments are Ngau Tam Mei and Tai Po Water WTWs, of which employ ozonation as a disinfectant and greatly reduce the use of chlorine. Ngau Tam Mei WTW, in particular, underscores our ability to optimally use limited land by incorporating specially designed landscaping features that also blend in with the natural environment.

Another example is Tai Po WTW, which is the first plant in Hong Kong to utilise a four-log disinfection treatment, achieving a 99.9% disinfection rate through ozonation. By adopting air flotation, biological filtration and rapid gravity filtration as primary treatment processes, Tai Po WTW’s treated water is better than the requirement as stated in the World Health Organisation’s (WHO) Guidelines for Drinking-water Quality. The project demonstrates our commitment to innovative sustainability, which results in better utilisation of resources and protection of the environment.

Left: ATAL employs highly effective water treatment processes to ensure the best water quality

Middle: Ngau Tam Mei WTW underscores ATAL’s ability to optimally use limited land by incorporating specially designed landscaping features

Right: Tai Po WTW’s treated water is better than the requirement as stated in WHO’s Guidelines