Qionghai Heshui Reservoir Water Conservancy Scenic Area

Qionghai Heshui Reservoir Water Conservancy Scenic Area

Qionghai Heshui Reservoir Water Conservancy Scenic Area is a national AAA-level tourist attraction and a national water conservancy scenic area.

Qionghai City’s Heshui Reservoir is located in Futian Town within the city’s Xinyuan water system. It was constructed in October 1965 as a homogeneous earth dam, with the main dam crest stretching 950 meters in length and one auxiliary dam measuring 325 meters long. In 1966, the earth dam reached its designed elevation. The upstream slope protection of the earth dam utilized three types: 50×50×10 cm precast concrete blocks, 10 m × 1 m × 10 cm cast-in-place concrete slabs, and 30 cm-thick mortar-laid stone (with a 15 cm-thick sand and gravel cushion layer). The dam is situated in a strong typhoon-prone area, posing significant threats to its safety. Between 1970 and 1972, the dam and its slopes suffered multiple damages. The most severe destruction occurred during Typhoon No. 20 in 1972, when all precast concrete slope protections were washed away, and 350 meters of the earth dam on the left bank of the spillway collapsed severely. During Typhoon No. 14 in 1973, the pedestrian bridge at the first bay on the right bank of the spillway was also pushed downstream by 5 cm due to the typhoon. In 1976, the slope was rebuilt with mortar-laid stone protection, and a 1-meter-high mortar-laid stone wave wall was also constructed. Since then, it has been operating safely.

The reservoir is close to the sea, and the sea breeze contains salt and alkali, which can corrode metal structural equipment and lead to easy damage.

The spillway is located in the middle of the main dam and features a broad-crested weir controlled by six 6×3.2 m flat steel gates. It has a mortar-laid stone steep slope, with an anti-scour concrete facing poured at the bottom for energy dissipation through bottom flow. The mortar-laid stone base plate had serious leakage issues. In 1982, four transverse and two longitudinal seepage drainage ditches were reconstructed to divert and discharge seepage water, reducing uplift pressure on the base plate. In 1980, a concrete seepage cutoff wall was also built in front of the gate chamber.

The designed irrigation area is 1,633 hectares. There are currently two main canals, totaling 20.1 km in length (including 2.4 km of concrete pipes and 4.2 km of concrete seepage prevention), and branch canals spanning 86.5 km (including 2.1 km of concrete pipes and 24 km of concrete seepage prevention). The canal embankments have 11 km of drivable mileage. The current irrigated area is 1,167 hectares.