​​Following is a question by the Hon Kenneth Lau and a written reply by the Secretary for Development, Ms Bernadette Linn, in the Legislative Council today (September 10):

Question:

     The Hong Kong Observatory has recently issued the Black Rainstorm Signal on multiple occasions. It is learnt that consecutive rainstorms have caused serious flooding in a number of rural areas, including South Lantau Road on Lantau Island, Ham Tin Kau Tsuen and Ham Tin San Tsuen (Ham Tin Tsuen), Shap Long Kau Tsuen and Shap Long San Tsuen (Shap Long Tsuen), and Yung Shue Wan on Lamma Island. After the consecutive black rainstorms, I have visited Ham Tin Tsuen and Shap Long Tsuen, where a relatively large number of elderly persons reside. Local villagers have relayed that flooding into houses occurred during every rainstorm, causing all their electrical appliances and wiring to be soaked and posing dangers; however, when villagers telephoned the relevant government departments for assistance, no immediate handling was provided, resulting in heavy losses on their part and leaving them at a loss. In this connection, will the Government inform this Council:

(1) of the numbers of flooding reports from villages in South Lantau received by the authorities in each of the past five years; the main causes for the occurrence of flooding in such cases; the handling time required and outcome for each case respectively;

(2) regarding the situation of flooding into houses and damage to wiring and electrical appliances occur during every rainstorm relayed by the aforesaid villagers, of the immediate or long-term remedial measures that the Government will adopt;

(3) whether it has regularly (for example, annually or quarterly) inspected and cleared the drainage channels in the aforesaid areas to ensure proper functioning of the drainage systems; if so, of the situation of blockage of drainage channels found during the inspections, as well as the respective numbers of relevant inspections and clearances; and

(4) in the face of increasingly frequent extreme weather events, of the measures in place to assist villagers in the aforesaid areas (especially elderly persons) to enhance their capabilities in coping with rainstorms and flooding; whether it will strengthen the support for them under rainstorms and flooding in future (for example, setting up a dedicated hotline or a response team)?

Reply:

President,

     In coping with extreme weather, the Government has developed a forward-looking Integrated Flood Management Strategy under a framework of advanced emergency preparedness, enhanced early warning, decisive emergency response and speedy recovery, to combat the impacts brought by climate change. This strategy aims to integrate adaptation, response, and management to enhance the overall flood resilience of Hong Kong. Regarding the situation in rural areas, in addition to carrying out improvement works to local drainage systems, the Government is also continuously strengthening related flood management work to enhance the flood protection abilities.

     My respective replies to the various parts of the Hon Kenneth Lau's question are as follows:

(1) Over the past five years (from 2020 to August 2025), the Drainage Services Department (DSD) has confirmed seven flooding cases in South Lantau. The details are as follows:
 

Year	No. of Confirmed Flooding Case
2025 (up to August)	2
2024	2
2023	0
2022	0
2021	2
2020	1

     According to the investigation results, the aforementioned flooding cases were primarily caused by heavy rainfall, during which a large amount of fallen leaves and debris were washed into low-lying roadside gullies, intakes, and drainage channels, leading to blockages. This hindered the natural flow of rainwater into the downstream stormwater collection and drainage systems, leading to flooding. All of these flooding cases were handled and resolved within one to two hours.

(2) to (4) The DSD conducts regular inspections, cleansing, and maintenance of public stormwater drainage systems. For example in South Lantau, the department has completed 28 inspections and cleansing operations for the public stormwater drainage system as of August this year.

     The DSD maintains close collaboration with the Hong Kong Observatory (HKO). Before the onset of a heavy rainstorm, the department implements a "just-in-time clearance" arrangement. Manpower will be deployed to inspect and clear drains that are prone to blockages caused by fallen leaves and debris, so as to reduce the risk of flooding during heavy rain. Additionally, when the HKO issues a Red or Black Rainstorm Warning Signal, a Special Announcement on Flooding in the northern New Territories or a Tropical Cyclone Warning Signal of number 8 or above, the DSD will immediately activate its Emergency Control Centre and deploy emergency response teams to address public requests for assistance and handle flooding cases.

     Currently, there are approximately 240 drainage points in Hong Kong that are prone to blockage, more than half of which are located in the New Territories and Islands, including four in South Lantau. To further enhance the response capabilities of Emergency Control Centre during extreme weather conditions, the DSD has increased the number of emergency response teams from 160 last year to 180 this year. Additionally, over 30 emergency operation stations across the territories have been established. The emergency operation station at Mui Wo can quickly deploy emergency response teams to South Lantau, including areas such as Ham Tin Village and Shap Long Village to tackle flooding incidents.

     Following every heavy rainstorm, the DSD reviews the causes of each flooding case and collaborates with relevant departments to discuss and implement necessary drainage improvement works, aimed at mitigating flood risks. In response to recent flooding incidents caused by heavy rain, the Government plans to carry out drainage improvement works in Ham Tin Village and Shap Long Village, such as installing additional drainage pipes and providing technical support for residents to install flood barriers.

     The DSD has implemented several support measures to help the public to cope with flooding incidents. These include establishing a 24-hour hotline (2300 1110) to efficiently receive and swiftly handling flooding reports. In addition, relevant government departments, such as the Home Affairs Department, the Highways Department, and the Food and Environmental Hygiene Department, conduct regular inspections and cleansing of related stormwater drainage facilities. The DSD maintains close liaison with these departments to ensure the proper functioning of the public stormwater drainage system. The DSD will continue to liaise with the local community and gather feedback from citizens with a view to further reducing the flooding risks in the affected areas.

Ends/Wednesday, September 10, 2025
Issued at HKT 15:47

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