ASSESSMENT OF THE STATE OF SURFACE WATER QUALITY IN CAU GIAY DISTRICT, HANOI CITY

Abstract

The study evaluates the surface water quality in Cau Giay district by taking water samples of some rivers and lakes inside study area. 8 water samples from 5 lakes in the research area were taken and analyzed for 8 parameters including pH, Temperature, DO, BOD₅, COD, NO₃^-, NH₄⁺, Coliform, combined with Automatic monitoring data of To Lich river water quality which has been collected in the dry and rainy season (March and August) of 2023 to analyze parameters, Water Quality Index (WQI) calculations and compare with QCVN 08-MT:2023/BTNMT to evaluate water quality. The results indicated that (1) The source of water discharged into rivers and lakes in Cau Giay district is mainly domestic wastewater and production areas; (2) In dry season, there are 5 parameters including DO, BOD₅, COD, NH₄⁺, Coliform exceeding the allowable limit value according to QCVN 08-MT:2023/BTNMT, the WQI values ranging from 33.37-80.62; (3) In rainy season, there are 3 parameters including DO, BOD₅, COD that exceed the allowable limit value according to QCVN 08-MT:2023/BTNMT, the WQI values ranging from 84.48-95.69. Based on obtained results, this study proposes several solutions to enhance the effectiveness of local surface water management.