This study was done at Cam Gia commune in Thai Nguyen city. The result showed that surface water quality at Cam Gia was contaminated by oil, some heavy metals, COD, BOD5 due to the effects of waste water from factories in the area: concentration of oil exceeds 1.8 times
Pb exceededs 6.4 times, Fe exceeds from 1.12 to 1.44 times, COD exceededs from 1.23 to 1.66 times, BOD exceededs 1.84 times the Vietnamese standard (TCVN5942: 1995(B)). This source of water is hazardous, threatening to health of people here and makes environmental pollution.