Field Study of Shing Mun River Handbook for Tour Guides and Primary School Teachers Contents Page 1. Notes on Field Study of Rivers 2 2. Shing Mun River and Fieldwork Sites 3 3. About Shing Mun River 4 4. Ecology 8 5. Cultural Heritage 9 6. Fieldwork Site A: Tai Shing Stream 10 7. Fieldwork Site B: Shing Mun Catchwater 12 8. Fieldwork Site C: Gorge Dam, 14 Upper Shing Mun Reservoir 9. Fieldwork Site D: Heung Fan Liu 16 10. Fieldwork Site E: Man Lai Court 18 11. Fieldwork Site S1: Che Kung Temple 20 12. Fieldwork Site F: Estuary 22 13. Fieldwork Exercises 24 Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 1 1 Notes on Field Study of Rivers Safety Measures 1. Wear a long-sleeved shirt and trousers to reduce the chance of insect bites and to avoid cuts and stings from vegetation; 2. Wear slip-resistant shoes; and 3. Leave the vicinity of the river immediately if there is a sudden rise in water level or an increase in the turbulence and turbidity of the stream flow. Code of Conduct 1. Protect the countryside and its environment. Do not pollute rivers or leave litter. 2. Do not disturb vegetation, or wildlife and their habitats. 3. Respect villagers and do not damage private property, crops, or livestock. Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 2 Shing Mun River and Fieldwork Sites 2 Map 2.1: Shing Mun River Catchment and Fieldwork Sites • Tai Shing Stream（大城石澗） A • Shing Mun Catchwater（城門引水道） B • Gorge Dam, Upper Shing Mun Reservoir C （上城門水塘主壩） • Heung Fan Liu（香粉寮） D • Man Lai Court（文禮閣） E • Che Kung Temple（車公廟） S1 • Estuary（河口） F Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 3 About Shing Mun River 3 1. About Shing Mun River Shing Mun River flows through the central New Territories, southeast of Tai Mo Shan (大帽 山). Its main stem originates from the south of Tai Mo Shan’s summit, at an altitude of 930m – the highest headwater for a river in Hong Kong. The highest section of the main stem, Tai Shing Stream (大城石澗), initially flows northeast from the headwater. The stream then turns southeast and flows down into Upper Shing Mun Reservoir (上城門水塘), situated in a valley towards the southwest. From there, the river flows southeast through Shing Mun Gorge (城門峽), where Upper Shing Mun Reservoir’s Gorge Dam is located, and enters Lower Shing Mun Reservoir (下城門水塘), formerly a river valley. After passing the main dam of Lower Shing Mun Reservoir, it zigzags northeast through Tai Wai and becomes Shing Mun River Channel, before converging with Kwun Yam Shan Stream (觀音山溪), Siu Lek Yuen Nullah (小瀝源明渠), and Fo Tan Nullah (火炭明渠), and finally entering Sha Tin Hoi, or Tide Cove (沙田海), at Sha Tin Sewage Treatment Works. The former estuary of the Shing Mun River is situated near the Hong Kong Heritage Museum. The river channel located from the museum to Sha Tin Sewage Treatment Works was artificially reclaimed from a shallow sea. The horizontal length of Shing Mun River’s main stem is 16.5km with an average gradient of 0.056 (or 1:17.7). The catchment area is about 58km2. Map 3.1: Shing Mun River Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 4 Figure 3.1: Headwater of Shing Mun Figure 3.2: The highest section of River at the summit of Tai Mo Shan Shing Mun River’s main stem (near the Civil Aviation Department is known as Tai Shing Stream Radar Station) Figure 3.3: The reclaimed former estuary of Shing Mun River “Rivers@HK Database” [Shing Mun River > Shing Mun River Location and Catchment > About Shing Mun River] https://bit.ly/3gtJPcX Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 5 2. River Management Since the 1920s, Shing Mun River has undergone major works, including the construction of catchwaters, water intakes, and reservoirs. The completion of Shing Mun Reservoir separated the upper and lower course of the Shing Mun River hydrologically and ecologically, indirectly impacting agricultural activities around Sha Tin. Later, large-scale reclamation for new town development also led to drastic alterations to the river’s estuary and tributaries. Irrigation In the past, residents of Sha Tin Valley relied on hill streams and wells for water. Even in the 1980s, some Sha Tin villages lacked tap water, making streams and wells essential for inhabitants. Villagers also influenced the river through other activities, for example, by building weirs to store stream water for irrigation. Waterworks In 1923, the government launched the large-scale Shing Mun Water Supply Scheme. Running over 16 years, the scheme resulted in the construction of Upper Shing Mun Reservoir, Kowloon Reception Reservoir, Shek Lei Pui Water Treatment Works, and several water tunnels. The Lower Shing Mun Reservoir was completed later in 1964. These works collected river water from Shing Mun Valley and Sha Tin Valley, diverting it to the aforementioned reservoirs. New Town Development The original mouth of Shing Mun River was situated at Sha Tin Tau. In the 1970s, construction of the current Shing Mun River Channel, which flows through the town centres of Tai Wai, Sha Tin, and Fo Tan, took place after large-scale reclamation of the shallow sea beyond the former estuary. Channelisation saw the downstream Shing Mun River at Tai Wai become the Tai Wai Nullah, and other tributaries in Sha Tin Valley either channelised or converted to culverts. Improvement of Water Quality The drastic reduction of flow as a consequence of river works lowered the self-purifying capacity of the lower course, making Shing Mun River Channel susceptible to water pollution, along with foul-smelling sedimentation and red tides. The Water Pollution Control Ordinance and Livestock Waste Control Scheme, sludge treatment from water treatment works, introduction of dry-weather flow inceptors, Tolo Harbour Sewerage Master Plan, Tolo Harbour Effluent Export Scheme, and Shing Mun River Improvement Works have together resulted in a remarkable improvement in the overall water quality of Shing Mun River. Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 6 Figure 3.4: Upper Shing Mun Reservoir Figure 3.5: Sha Tin New Town Figure 3.6: Shing Mun River Channel River Revitalisation In 2019, the Drainage Services Department announced a proposal to revitalise Fo Tan Nullah and Tai Wai Nullah. Under the proposal, the channelised section will be transformed into a green open space to enhance connectivity between rivers and human communities, with the feasibility of allowing public access for water-friendly activities also being explored. The revitalisation projects are expected to commence in 2024. “Rivers@HK Database” [Shing Mun River > Shing Mun River Location and Catchment > River Management] https://bit.ly/3gtJPcX Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 7 Ecology 4 As the upper course of Shing Mun River falls into water gathering grounds and country park areas, natural streams there have largely been preserved. With dense vegetation cover and excellent water quality, the area is home to a wide variety of freshwater fish, amphibians, insects, and aquatic invertebrates. The Fung Shui Wood located in the northern Shing Mun Valley is of particular note, being designated a Site of Special Scientific Interest (SSSI) due to its high biodiversity, with over 70 tree species recorded. However, water discharged into the lower course of Shing Mun River, has reduced drastically, as much of the river water in the upper and middle courses is now being intercepted by or diverted to reservoirs via waterworks, breaking down hydrological linkage and causing freshwater habitats to deteriorate. In addition, large-scale river training and reclamation works carried out in Sha Tin New Town have significantly changed the lower course and estuary, transforming these areas into artificial, concrete-lined channels of low ecological value. Figure 4.1: Black-banded Gossamerwing Figure 4.2: Predaceous Chub (Euphaea decorata) (Parazacco spilurus) “Rivers@HK Database” [Shing Mun River > Ecology] https://bit.ly/2U5YbHv Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 8 Cultural Heritage 5 Sha Tin was formerly known as Lek Yuen (瀝源), which refers to sources of clean water. Endowed with a plentiful water supply from Shing Mun River and fertile soil, people settled and farmed in Sha Tin Valley as early as the Ming Dynasty. A number of villages were established, including Tin Sum Wai (田心圍) and Chik Chuen Wai (積存圍). By the Qing Dynasty, a rural alliance known as the Nine Yeuks (沙田九約) was set up to foster a close relationship between the villages. Today, while much of the rural landscape has disappeared as a result of new town developments, some cultural heritage sites can still be found, including Tsang Tai Uk (曾大屋) and Che Kung Temple (車公廟). Figure 5.1: Tsang Tai Uk Figure 5.2: Che Kung Temple “Rivers@HK Database” [Shing Mun River > Cultural Heritage] https://bit.ly/3vyUNC2 Field Study of Shing Mun River: Handbook for Tour Guides and Primary School Teachers 9 6 Fieldwork Site A: Tai Shing Stream Tai Shing Stream, which flows from Tai Mo Shan to Upper Shing Mun Reservoir, forms part of the upper course of Shing Mun River. Large boulders scattered along the stream are a typical feature. As the stream is located in the water gathering ground and a country park, it remains largely pristine with abundant flow, providing habitats for a wide variety of freshwater creatures, such as the Hong Kong Newt (Paramesotriton hongkongensis).