Set in the northwest New Territories, Tuen Mun River originates at an altitude of 480m, northeast of Kau Keng Shan (at an altitude of 507m), to the east of Tuen Mun. The main stream flows first northwest to a ravine, and then north into Lam Tei Irrigation Reservoir. To the west of Lam Tei Quarry it turns west at Fu Tei Ha Tsuen, and then southwest at Siu Hong Court before entering the Tuen Mun Valley, passing Tuen Mun New Town and finally flows into Tuen Mun Typhoon Shelter in Castle Peak Bay Deep Bay at Wu Shan Playground. The estuary of the old Tuen Mun River is between Pui To Road and Hau Kok Tin Hau Temple. The channel south of Pui To Road was artificially reclaimed from the shallow sea. The artificial channel south of Siu Hong Court is now known as Tuen Mun River Channel.


The basin of Tuen Mun River is divided into eastern and western sections by western ridge of Kau Keng Shan. The main stream makes a U-turn at Fu Tei Ha Tsuen that flows from the smaller eastern to larger western basin (Tuen Mun Valley). The eastern basin rises to Kau Keng Shan. To the west and east are the ridges of Kau Keng Shan, and to the north is an alluvial plain at Lam Tei. The western basin, where Tuen Mun Valley lies, is larger than the eastern basinl. To the north is the saddle between Yuen Tau Shan and Kung Um Shan, connecting to Yuen Long Plain. To the west is Castle Peak; to the east is the western ridge of Kau Keng Shan beside main stream.

The various streams originating from the headwater at Kau Keng Shan flow in different directions and form a typical radial drainage pattern. The main stream converges with other tributaries on the northern slope, creating a dendritic drainage pattern. Lo Fu Hang, eroding along a fault, has a rectangular drainage pattern formed by over ten tributaries flowing parallel from the east and west of the valley and entering the main stream at almost a right angle. The tributaries on the eastern side of Tuen Mun Valley form a rectangular drainage pattern, and those on the western side form individual dendritic drainage patterns. The main stream of Tuen Mun River stretches 8.7km, measured horizontally, at an average gradient of 0.056 (or 1:17.9). The river basin area is about 21km.


Source of Tuen Mun River on northern slope of Kau Keng Shan

Tuen Mun River Channel






Lo Fu Hang is eroding a course along a long straight fault

Tuen Mun Valley is connected to the alluvial plain of Yuen Long and Tin Shui Wai in the north

Copyright 2010 by Green Power All rights reserved.