A Study on Seasonal Pollutant Distribution Characteristics of Contaminated Tributaries in Nakdong River Basin

Abstract

This study has performed comparative analysis on characteristics of contaminated 35 tributaries on seasonal variation/point discharge load/pollutant distribution of water quality factors(8) in order to understand the effect of the watershed in Nakdong River Basin. As a results, the water quality of BOD 5 (Biochemical Oxygen Demand), Chl-a(Chlorophyll a) and Fecal E. Coli shows Ⅱ grade at tributaries of more than 50% without COD(Chemical Oxygen Demand), TP(Total Phosphate), TOC(Total Oxygen Carbon) and TN(Total Nitrogen) factors. The specific discharge(Q) were occupied about 54.4% (19 sites) as 0.05 m 3 /sec/km 2 value. Among these results, the contaminant level of Dalseocheon, Hyeonjicheon, Seokkyocheon 1, Uriyeongcheon and Dasancheon was also high, which has to consider a discharged pollutant load(kg/day). The 35 major tributaries of Nakdong River were included in 7 mid-watershed, such as Nakdong Waegwan, Geumho River, Nakdong Goryung, Nakdong Changnyung, Nam River, Nakdong Milyang, Nakdong River Hagueon. Especially, the discharged pollutant load of Nam River and Geumho River also was high according to the amount of discharge such as Kachang dam, Gongsan dam and Nam river dam. Seasonal difference of the water quality factors such as BOD 5 , TN, SS and Q was observed largely, on the other hand

Relationship between Coliform Bacteria and Water Quality Factors at Weir Stations in the Nakdong River, South Korea

“…Lee et al [9] also mentioned the impact of polluted tributaries on the Nakdong River mainstream for coliform bacteria. In addition, Yu et al [38] and Na et al [39] reported that highly contaminated secondary tributaries, which enter the Geumho River, could affect the water quality of the mid-and downstream section where Nongong station is located. Therefore, the rapid increase in the concentration of coliform bacteria at Nongong station was likely caused by pollutants carried by the Geumho River.…”