Lau Shui Heung Reservoir, built in 1968 as part of the Plover Cove Reservoir engineering programme, is a reservoir located within the boundary of Pat Sin Leng Country Park in the eastern part of North District, New Territories, Hong Kong, located at the northeast area of Bird's Hill, at the northeast end of Sheung Shui-Fanling Plain.

It was suspected that the nearby Lung Shan Tunnel Project had drained the groundwater.

[5] Until the beginning of June that year, due to the influence of the outer rainbands associated with Tropical Storm Ewiniar, nearly 100 mm of rainfall had fallen in the past 3 days, which was more than 10 mm more than the total rainfall of the past two months.

At the same time, more than 200 mm of rainfall was recorded in the past 24 hours in the northern New Territories, enough to fill the reservoir with a capacity of 170,000 m3 and restore the title of "mirror of the sky".

Many fish species can be found in the reservoirs, including Channa asiatica, which is uncommon in Hong Kong.