In this study, water quality levels were classified and water quality indices were calculated and analysed by using the water quality components of living environmental standards monitored 10 years (2008 ~ 2017) at four stations in the West Nakdong River. As a result of analyzing the monthly variation of the water quality components of the living environmental standards, the water quality in the West Nakdong River was worse downstream than upstream, and pollution at the WNR3 located in the downstream of the Jomangang was the most serious. As a result of classification of water quality levels, BOD and COD levels were the lowest, so water quality pollution in the West Nakdong River was found to be highly influenced by organic matters. The water quality index was the lowest in July and August at four stations, so water quality is showing the worst in summer. As a result of analyzing the correlation between the water quality components and the water quality index, the correlation between the TOC and the water quality index was high in the four stations, and the water quality index in the West Nakdong River was dominated by organic matters and nutrients.

In this study, the water quality components (pH, BOD, COD, TOC, SS, DO, TP) and the water quality, observed for 10 years (2008~2017) in the five tributaries of the Nakdong River with the highest flow rates, were analyzed. Monthly levels of the water quality components were estimated and regression functions were used to quantitatively explain the changes in the BOD and COD components, with respect to the TOC components. The results of analyzing the water quality levels in terms of the living environmental standards show that the lowest water quality was observed midstream (ST-3) and the highest water quality was observed upstream (ST-1 and ST-2). The regression function was estimated to be a linear function in all five tributaries, and the goodness of fit of the function was high upstream (ST-2), midstream (ST-3), and downstream (ST-4). According to the regression analysis using the observation data from 2008~2017, we found that the consumption of dissolved oxygen increased with an increase in organic matter in the major tributaries of the Nakdong River.

For the purpose of protecting the health of citizens and creating a delightful environment, the Government shall establish the environmental standards, and make such standards keep their propriety according to any changes in environmental conditions. The Special Metropolitan City, Metropolitan City or Do may, in case where deemed necessary in view of the speciality of regional environments, set forth the separate environmental standards which are more expanded and strengthened than the environmental standards by the Municipal Ordinance of the relevant City/Do. The purpose of this study was for the management of stream waters of Jeju Island and proposed the appropriate Jeju local river environmental standards. Jeju-Do and Daejeon-si applies the Local River Environmental Standards in Korea. While each nationʹ circumstances and environment are different, for the most part, environmental standards and purposes of use are similar to those in Korea. Proposed Jeju River Local Environment Standards followed The River Environment Standards of Nation(Korea) for Living Environment Standards. Newly Strengthened Value is Cd, Carbon tetrachloride, 1,2-dichloroethene, Tetrachloroethylene(PCE) and add Items is Fluorine, Selenium, Phenol and Toluene for Human Health Protection.