Water resources

Above ground water: The volume of water in rivers is rather great, estimated about 8,776 billion m3 and generated in the whole region. The water current is up to 118 litre/second/km2 in heavy rain areas. The same as the anunual rainfall, river current in Quảng Ninh Province is also divided into two distinct seasons. Rainy season is from May to September with the water volume accounting for 75-80% of the total water volume in a year, dry season is from October to April with 20-25% of water volume in a year.

Underground water: According to survey results, underground water reserve in Cẩm Phả region is 6.107 m3/day, in Cửa Ông - Cọc Sáu region 14.730 m3/day, Ha Long region 21.290 m3/day.
 
Taking advantage of these geographical figures nearly thirty big lake dykes have been built with the total capacity of 195.53 million m3 to serve socio-economic purposes in the province such as Yên Lập lake (118 million m3), Chúc Bài Sơn (11.5 million m3), Quất Đông (10million m3). Quảng Ninh has a total of 2,500 – 3,000 hectares of lake and pond surface which can be used to raise aquatic animals.