Drainage Services Department

To acquaint the public with knowledge of the causes of flooding and of the Government's strategy to tackle flooding in Hong Kong, the Drainage Services Department (DSD) has engaged "GREEN POWER" to co-organize “Encounter with Rivers – Yuen Long Bypass Floodway Public Guided Tour” leading the public to visit Yuen Long Bypass Floodway, Yuen Long Bypass Floodway Engineered Wetland (opened in November and December every year only), Kam Tin River and Ramsar Site to allow members of the public gaining a deeper understanding of river ecology and biodiversity in Hong Kong through observing elements of preservation of ecosystems in rivers incorporated into DSD's flood prevention works.

Yuen Long Bypass Floodway is a 3.8 kilometres long drainage channel built at the south of Yuen Long Town. Different from the traditional river training works which increase the flow capacity of the rivers by straightening, widening and deepening the river channels, Yuen Long Bypass Floodway (YLBF) adopts the method of interception, intercepts 40% of the runoff in the Yuen Long Catchment, and then discharges the intercepted flow to the Deep Bay without passing through the Yuen Long Town, which reduces the flood risk of Yuen Long significantly.

DSD strives to revitalize water bodies by incorporating green and eco-conservation elements into a number of projects in hopes of beautifying river environment and promoting ecological conservation while actively providing Hong Kong with a high degree of flood protection. The Bypass Floodway has incorporated a series of environmental designs, its flow is not carried straight to the sea but passing through different regimes including bends, shallow ponds and wetland. The channel bottom and slope are covered by different species of herbaceous plants to provide a natural riverbank with aesthetic and ecological value. A system of dry weather flow pumping station and inflatable dam is provided at the downstream end to control the water level in the Bypass Floodway and to prevent polluted water in the downstream from flowing back into the Bypass Floodway. 

For details about Yuen Long Bypass Floodway, please click here.

Yuen Long Bypass Floodway Guided Tour
Applications of Yuen Long Bypass Floodway Guided Tour are accepted all year round. 
This guided tour will take you to the San Tin Stormwater Pumping Station, Low Flow Pumping Station and Inflatable Dam located at Yuen Long Bypass Floodway, Mangroves of Kam Tin River and Nam Sang Wai Kam Tin River Estuary throughout the itinerary. The entire visit takes about 1.5 hours.

Available Visiting Date and Time:
From 10:00 AM to 11:30AM or 2:30PM to 4:00PM
From Mondays to Saturdays, except Public Holidays

Yuen Long Bypass Floodway Eco Tour
Yuen Long Bypass Floodway Eco Tours are only opened on designated dates from November to December.
This guided tour will take you to the San Tin Stormwater Pumping Station, Low Flow Pumping Station and Inflatable Dam located at Yuen Long Bypass Floodway, Yuen Long Bypass Floodway Engineered Wetland, Mangroves of Kam Tin River and Nam Sang Wai Kam Tin River Estuary throughout the itinerary. The entire visit takes about 2 hours.

Available Visiting Date and Time:
From 10:00 AM to 12:00PM or 2:30PM to 4:30PM
From Mondays to Saturdays, except Public Holidays

Virtual Tour
In addition to our-site guided tour, virtual tour of “Encounter with Rivers – Yuen Long Bypass Floodway Guided Tour” is also available to allow public to explore flood prevention facilities from multiple perspectives through the Internet and to learn more about DSD’s works in ecological conservation incorporated in flood prevention projects anytime and anywhere.

Theme 1: Yuen Long Bypass Floodway Guided Tour
Theme 2: Yuen Long Bypass Floodway Eco Tour

While you maintaining social distance and reducing outdoor activities during the coronavirus pandemic, you can still learn more about DSD comfortably at home.

Applications of Virtual Tour are accepted all year round. Schools and organisations are welcome to apply the guided tour in according to their interests and teaching needs through the prior application. The entire visit takes about 45 minutes to 60 minutes.

Available Visiting Date and Time:
From 10:00 AM to 5:00PM
From Mondays to Saturdays, except Public Holidays

For details of visit application and latest update, please visit the following websites:

GREEN POWER – “Encounter with Rivers – Yuen Long Bypass Floodway Public Guided Tour”

GREEN POWER – “Encounter with Rivers – Yuen Long Bypass Floodway Public Guided Tour” Facebook Page

GREEN POWER – “Encounter with Rivers – Yuen Long Bypass Floodway Public Guided Tour” Instagram

Connection point between Yuen Long Bypass Floodway and Yuen Long Nullah	Connection point between Yuen Long Bypass Floodway and Yuen Long Nullah
Low Flow Pumping Station	Inflatable Dam
Mangroves of Kam Tin River	Mangroves of Kam Tin River
Nam Sang Wai Kam Tin River Estuary	Nam Sang Wai Kam Tin River Estuary
Yuen Long Bypass Floodway	Inflatable Dam at Yuen Long Bypass Floodway
Yuen Long Bypass Floodway Engineered Wetland	Yuen Long Bypass Floodway Engineered Wetland
Nam Sang Wai Kam Tin River Estuary	Yuen Long Bypass Floodway Engineered Wetland
Ramsar Site at Deep Bay	Nam Sang Wai Kam Tin River Estuary

For inquiries, please contact GREEN POWER at 9746 1725 or DSD at 2594 7140.