Happy Valley Underground Stormwater Storage Scheme is designed to alleviate flood risk in the Happy Valley and Wan Chai area, the scheme involves construction of a 60,000m³ underground stormwater storage tank, a pump house, a fan room, a 650m long twin-cell box culvert and associated works including reinstatement of sports pitches and landscaping.
By applying the alternative foundation design, 2,000 tons of steel and 6,000m³ of grouting material has successfully abridged, it massively allows the project to shorten the construction period by 3 months and saved HKD$72M for the construction cost.
In addition, the treated harvested water would be reused on the sports pitches and public toilets, resulting a maximum of 220,000m³ potable water saved annually.
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Happy Valley Underground Storage Scheme commissioning ceremony
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The interior of the Happy Valley underground stormwater storage tank.
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The project incorporated the current largest water harvesting system in Hong Kong that collects groundwater, irrigation water and rainwater for toilet flushing and pitch irrigation purposes.