Field trip

Happy Valley Underground Stormwater Storage Scheme

Happy Valley is a low‐lying urban area located in the hinterland of the Wan Chai District and is surrounded by a hilly terrain. Serious flooding occurred in the Happy Valley catchment, in particular the Happy Valley Recreation Ground (HVRG), Hong Kong Jockey Club racecourse and nearby streets, during heavy rainstorms in 2000, 2006 and 2008. To address the flooding problem, Happy Valley Underground Stormwater Storage Scheme (HVUSSS) at the HVRG is constructed. The scheme would raise the flood protection level of the drainage system in Happy Valley to cater for rainstorms with a return period of 1 in 50 years, and in turn significantly reduce the risk of flooding in Happy Valley and areas in the vicinity.
      The HVUSSS greatly enhanced the flood protection level of the city and solved the flooding problems in Happy Valley and Wan Chai districts. The adoption of an innovative underground spillway energy dissipation and flow conveyance design, a system of smart and automatic movable weirs with real time control, water harvesting system and green building designs have created a more resilient and adaptable drainage system that blends harmoniously with the environment. It has been awarded the 2018 Dai Yu Science & Technology Medal of Chinese Hydraulic Engineering Society (“中國水利學會「大禹水利科學技術獎」”) for the outstanding achievements of the HVUSSS in the area of innovations and technology development.

Hong Kong West Drainage Tunnel (HKWDT) intakes

In the early 2000s, the Drainage Services Department proposed an innovative “upstream interception” scheme, namely The Hong Kong West Drainage Tunnel (HKWDT) to improve the flood protection standard for areas around Causeway Bay, Admiralty, Central and Sheung Wan.
     The engineering challenge was how to effectively intercept and transfer the supercritical (high speed) flow from the steep natural watercourses located in the densely‐populated Mid‐Levels district to the drainage tunnel located some 100 m below ground. The breakthrough was the development of a compact bottom rack and vortex intake system to stably decelerate the supercritical flow, with efficient energy dissipation, for smooth conveyance of flow from higher elevations to the deep drainage tunnel and discharge to the sea.
     Since commissioning of the HKWDT in 2012, the vortex intake system has been put to the test on many severe rainfall occasions, and successfully protected the downhill urban areas of Hong Kong Island from flooding. This system has set a global standard for reference and the new vortex intake design method has been adopted in many critical hydraulic infrastructure designs internationally.
     The supercritical vortex intakes for the Hong Kong West Drainage Tunnel (HKWDT) won the First Prize of Construction Sustainability in Construction Innovation Award 2017 of the Hong Kong Construction Industry Council (CIC).

Smart Urban Water Supply Systems field testing facility

Smart Urban Water Supply Systems field testing facility, the first of its kind in Hong Kong and Greater China, is constructed at the Beacon Hill Intermediate Level Freshwater Reservoir in Kowloon Tong, next to Lung Cheung Road. The facility was designed and developed by HKUST with the support of the Hong Kong Water Supplies Department. This unique facility provides an opportunity to test in‐pipe wave propagation with a degree of realism not possible with laboratory experiments without interference to the normal supply of water to the public. A 250 m long pipeline network of 150 mm HDPE pipe has been constructed along the periphery of the site (covering a footprint of around 65 m x 65 m). The water supply is fed from the Beacon Hill reservoir at around 60 m of head; the flow is monitored by an electromagnetic flow meter, and the upstream pressure can be set with a Pressure Reducing Valve (PRV). A valve designed for rapid closure is installed at the downstream end of the system. Pressure transducers, branches and leaks can be installed at selected nodes. The facility permits field‐scale experiments on advanced, transient‐based, diagnostic methods for leakage/fault detection and pipeline wall condition assessment.