VietNamNet Bridge – The latest research by the Northern Water Resource Planning and Survey Federation shows that arsenic in Hanoi’s water resources reaches 40 times more than allowed level.

Drilling and the overexploitation of water is the reason that Hanoi’s underground water resources are polluted.

The content of NH4 also exceeds the threshold by 20-30 folds in some places, while land depression is alarming in some sites in the capital city.

Dr. Nguyen Van Doanh, Chief of the Northern Water Resources Planning and Survey Federation, said that the quality of underground water resources is currently bad in some areas of Hanoi because of the exploitation of underground water resources.

According to Dan, Hanoi’s underground water resources are naturally clean, although the concentration of iron and manganese in the water is quite high. The most concerning issue at present is the content of arsenic and NH4, which are made from organic materials, dead animal bodies, and both liquid and solid waste, is too high.

The most seriously arsenic polluted areas are Dan Phuong (0.4 microgram/litre), 40 times more than allowed level (0.01 microgram/litre) and Nam Du (Thanh Tri District) (0.1-0.2 microgram/litre), 10-20 times more than permitted level.

Some other sites have high concentrations of NH4 in underground water that is up to 20-30 times more than the threshold, such as in the areas of Ha Dinh, Phap Van, Dinh Cong, Kim Giang, Bach Mai, Bach Khoa, Kim Lien and Quynh Mai.

The quality of water supply for some areas in the city, particularly in new residential areas, like Trung Hoa – Nhan Chinh, Dai Kim, Me Tri, Dinh Cong and Linh Dam, is said to be bad because water is contaminated with E.coli, Coliform, or has high concentration of iron.

Dr. Dan said drilling and the overexploitation of water is the reason that Hanoi’s underground water resources are polluted. Many unused private drilling wells are not filled in properly, and toxic substances go through these wells to pollute the underground water.

Research by the Northern Water Resource Planning and Survey Federation also revealed that the underground water level is significantly decreasing.

Dan said water exploitation and the existence of major construction projects is causing a depression in some areas of Hanoi. The Phap Van area is seeing a depression of over 3 cm per year.

According to the latest data about underground water in Hanoi, from 1991 until the present, from the Hanoi Institute for Science-Technology and Construction Economics, depression in some areas of the capital is up to 4 cm per year.

(Source: Tien Phong)