Officials Visit Drainage Services Department to Boost Flood Prevention and Sewage Treatment Efforts in Hong Kong

CS and SCS visit Drainage Services Department

The Chief Secretary for Administration, Mr Chan Kwok-ki, and the Secretary for the Civil Service, Mrs Ingrid Yeung, visited the Drainage Services Department (DSD) this afternoon (December 16) to learn more about the department's daily operations and the latest progress on its drainage improvement works. They also toured the Stonecutters Island Sewage Treatment Works (SCISTW), which is the largest of its type in Hong Kong. The Permanent Secretary for the Civil Service, Mr Clement Leung, also joined the visit.

Mr Chan and other officials first met with the Director of Drainage Services, Mr Ringo Mok, together with the directorate staff and were briefed on the department's progress on the drainage improvement works in Hong Kong. The DSD is taking forward expeditiously seven drainage improvement works projects, covering Wong Tai Sin, Hong Kong Island East and other areas hit by severe floods in the past. Apart from adopting parallel tendering, the department also strives to shorten the duration of engineering design, procurement and construction for commencing and completing the improvement works as soon as possible to enhance the flood prevention ability of the districts concerned.

To cope with the more frequent extreme weather conditions in recent years, the DSD is dedicated to strengthening the operation of the Emergency Control Centre and the emergency response teams, and applying innovative technologies to enhance work safety and efficacy. For instance, the deployment of a desilting robot, "River Ranger", for emergency clearance works, with a view to allowing the community to resume normal operation within the shortest period of time, and an underground drainage inspection robot, "Tumbler Inspection Ball", and crawler-type survey robots to conduct surveying works to determine the status of underground pipelines. A "Tumbler Inspection Ball" robot can provide 360-degree all-round stable viewing, and then combine the 360-degree real-life pictures with artificial intelligence, which helps officers check the pipeline status accurately. In addition, the DSD has made advance arrangements by completing the "Strategic Planning Study on Flood Management Against Sea Level Rise and Extreme Rainfall" soon and formulating new and comprehensive territory-wide flood management strategies.

Mr Chan said that in the face of various challenges brought about by climate change, the Government is dedicated to implementing a pre-emptive strategic approach and stepping up preventive and contingency measures on various fronts to protect the lives and property of people. He stressed that all government departments are working at full steam to scale up their handling capabilities to minimise as far as possible the impact of inclement and even extreme weather conditions on the community, while the DSD plays a vital role in flood prevention and clearing blockages in drainage systems.

Mr Chan advised the DSD to get prepared for the future rainy and tropical cyclone season by deploying adequate manpower and resources, stepping up inspection of its drainage facilities, carrying out timely desilting work, ensuring the clearance of drainage channels across the territory and disseminating information to the public properly. He and Mrs Yeung encouraged DSD colleagues to stand fast at their posts, rise to the challenges ahead, maintain close communication with other relevant departments and organisations, and demonstrate professionalism and team spirit in order to make good preparations for inclement and even extreme weather conditions.

Mr Chan and other officials then visited the SCISTW Main Pumping Station and were briefed by the staff on the DSD's work in taking forward the sewage treatment initiatives such as the Harbour Area Treatment Scheme. They also met with duty officers at the Main Control Room of the SCISTW to learn more about the department's work in monitoring various sewage treatment processes around the clock as well as its contingency strategies in case of inclement and even extreme weather conditions.

They then viewed the SCISTW from a green roof, where they were briefed on the sewage treatment facilities as well as the operation of facilities such as Clean Harbour 2, an advanced vessel for the transportation of sludge from the SCISTW to Tuen Mun for turning waste into energy. Meanwhile, they also gained a better understanding of the department's progress in promoting the use of renewable energy at the SCISTW, including the installation of thin-film photovoltaic systems, which is expected to be completed next year and will be the largest of its kind in Hong Kong.

Mr Chan hoped that the DSD would continue to break new ground while upholding fundamental principles, and spare no effort to provide world-class wastewater and stormwater drainage services, and at the same time help to build a sustainable and better future for Hong Kong by utilising innovative technology and renewable energy.

Mrs Yeung also met with staff representatives from various grades to exchange views on issues of concern.

CS and SCS visit Drainage Services Department Source: HKSAR Government Press Releases

CS and SCS visit Drainage Services Department Source: HKSAR Government Press Releases

CS and SCS visit Drainage Services Department Source: HKSAR Government Press Releases

CS and SCS visit Drainage Services Department Source: HKSAR Government Press Releases

CS and SCS visit Drainage Services Department Source: HKSAR Government Press Releases

FEHD releases fourth batch of gravidtrap indexes for Aedes albopictus in May

The Food and Environmental Hygiene Department (FEHD) today (May 21) released the fourth batch of gravidtrap indexes and density indexes for Aedes albopictus in May, covering 12 survey areas, as follows:

District

Survey Area

May 2026

First Phase Gravidtrap Index

First Phase Density Index

Eastern

Shau Kei Wan and Sai Wan Ho

9.1%

1.4

Islands

Tung Chung

2.0%

1.0

Kowloon City

Hung Hom and To Kwa Wan

6.7%

1.5

Tai Po

Tai Po East

2.2%

2.0

Tai Po West

15.5%

1.0

Tuen Mun

Tuen Mun South

9.1%

1.4

District

Survey Area

May 2026

Area Gravidtrap Index

Area Density Index

Central and Western

Kennedy Town and Shek Tong Tsui

16.8%

1.3

Eastern

Chai Wan

15.4%

1.0

North Point and Quarry Bay

18.9%

1.4

Southern

Aberdeen and Ap Lei Chau

20.8%

1.7

Sha Tin

Sha Tin Town Centre and Fo Tan

18.3%

1.4

Tsuen Wan

Tsuen Wan Town

6.9%

2.3

The fourth batch of gravidtrap indexes for Aedes albopictus in May includes First Phase Gravidtrap Indexes covering six survey areas and Area Gravidtrap Indexes covering six survey areas. Among which, six survey areas recorded gravidtrap indexes above 10 per cent, while Aberdeen and Ap Lei Chau in Southern District recorded a gravidtrap index above 20 per cent. Meanwhile, the gravidtrap indexes of six survey areas, namely Kennedy Town and Shek Tong Tsui in Central and Western District; North Point and Quarry Bay in Eastern District; Shau Kei Wan and Sai Wan Ho in Eastern District; Aberdeen and Ap Lei Chau in Southern District; Tai Po East in Tai Po District; and Tuen Mun South in Tuen Mun District, have recorded a decrease as compared to the indexes recorded in the last survey period, reflecting the progress of relevant mosquito control work.

With reference to the data from the past few years, the gravidtrap indexes start to rise from April or May every year. The actual timing and extent of the rise are affected by factors like weather conditions and rainfall. The average temperature and rainfall recorded in April this year were higher than those in the same period last year, creating favourable conditions for mosquito growth and breeding. As a result, the rise in gravidtrap indexes occurred earlier this year. With the increase in rainfall in May, the gravidtrap indexes are expected to rise further.

For survey areas which recorded indexes exceeding 10 per cent, in accordance with the mechanism implemented by the FEHD in response to the chikungunya fever (CF) situation (i.e. strengthening mosquito control work in areas with a gravidtrap index between 10 per cent and 20 per cent, instead of 20 per cent or above under the original mechanism), the FEHD is collaborating with relevant departments and stakeholders to identify locations with high mosquito infestations and carry out intensive and targeted mosquito control measures. The FEHD has initiated two prosecutions against the relevant construction site contractors following the discovery of mosquito breeding at construction sites in Tai Po District and Southern District. Moreover, following the discovery of stagnant water or stagnant water containers in a park, a construction site, a private housing estate, a clinic and a private premises in Tai Po District, Central and Western District, as well as Southern District, the FEHD has issued five statutory notices to the responsible persons-in-charge, requiring the clearance of such items within a specified timeframe. The FEHD, the relevant departments and stakeholders are following up on the mosquito control work, and will also organise exhibitions, distribute leaflets and posters, and notify residential estates that have subscribed to the gravidtrap Rapid Alert System, advising property management agents and residents to stay vigilant and work together in taking mosquito prevention and elimination measures. In addition, the FEHD will strengthen the monitoring of the gravidtrap index in the areas to review the effectiveness of the mosquito control work.

Public participation is crucial to the effective control of mosquito problems. The FEHD appeals to members of the public to continue to work together in strengthening personal mosquito control measures, including:

tidy up their premises and check for any accumulation of water inside the premises;

remove all unnecessary water collections and eliminate the sources;

check household items (those placed in outdoor and open areas in particular), such as refuse containers, vases, air conditioner drip trays, and laundry racks to prevent stagnant water;

change water in flower vases and scrub their inner surfaces thoroughly, and remove water in saucers under potted plants at least once a week;

properly cover all containers that hold water to prevent mosquitoes from accessing the water;

properly dispose of articles that can contain water, such as disposable meal boxes and empty cans; and

scrub drains and surface sewers with alkaline detergent at least once a week to remove any mosquito eggs.

Starting in August 2025, following the completion of the surveillance of individual survey areas, and once the latest gravidtrap index and the density index are available, the FEHD has been disseminating relevant information through press releases, its website and social media. It aims to allow members of the public to quickly grasp the mosquito infestation situation and strengthen mosquito control efforts, thereby reducing the risk of CF transmission.

Following recommendations from the World Health Organization and taking into account the local situation in Hong Kong, the FEHD sets up gravidtraps in districts where mosquito-borne diseases have been recorded in the past, as well as in densely populated places such as housing estates, hospitals and schools to monitor the breeding and distribution of Aedes albopictus mosquitoes, which can transmit CF and dengue fever. At present, the FEHD has set up gravidtraps in 62 survey areas of the community, with a surveillance period of two weeks. During the surveillance period, the FEHD will collect the gravidtraps once a week. After the first week of surveillance, the FEHD will immediately examine the glue boards inside the retrieved gravidtraps for the presence of adult Aedine mosquitoes to compile the Gravidtrap Index (First Phase) and Density Index (First Phase). At the end of the second week of surveillance, the FEHD will instantly check the glue boards for the presence of adult Aedine mosquitoes. Data from the two weeks of surveillance will be combined to obtain the Area Gravidtrap Index and the Area Density Index. The gravidtrap and density indexes for Aedes albopictus in different survey areas, as well as information on mosquito prevention and control measures, are available on the department's webpage (www.fehd.gov.hk/english/pestcontrol/dengue_fever/Dengue_Fever_Gravidtrap_Index_Update.html#).

FEHD releases fourth batch of gravidtrap indexes for Aedes albopictus in May Source: HKSAR Government Press Releases

FEHD releases fourth batch of gravidtrap indexes for Aedes albopictus in May Source: HKSAR Government Press Releases

FEHD releases fourth batch of gravidtrap indexes for Aedes albopictus in May Source: HKSAR Government Press Releases

FEHD releases fourth batch of gravidtrap indexes for Aedes albopictus in May Source: HKSAR Government Press Releases

FEHD releases fourth batch of gravidtrap indexes for Aedes albopictus in May Source: HKSAR Government Press Releases