| Title |
A Study on the Variation of Water Quality and the Evaluation of Target Water Q uality U sing L DC i n Major Trib utaries of N akdong R iver B asin |
| Authors |
이상수 ( Sangsoo Lee ) ; 강준모 ( Junmo Kang ) ; 박혜림 ( Hyerim Park ) ; 강정훈 ( Jeonghun Kang ) ; 김신 ( Shin Kim ) ; 김진필 ( Jin-pil Kim ) ; 김경훈 ( Gyeonghoon Kim ) |
| DOI |
https://doi.org/10.15681/KSWE.2020.36.6.521 |
| Keywords |
Flow duration curve; Load duration curve; Percentile Method; Target water quality; Water Quality |
| Abstract |
In this study, the variation of water quality was analyzed for six sites in major tributaries of the Nakdong River Basin. Standard-FDC (Flow Duration Curve) was developed using PM (Percentile Method), one of the statistical FDC estimation methods. The LDC (Load Duration Curve) was obtained using the developed FDC. The current method and the LDC evaluation method were compared and analyzed to evaluate the achievement of TWQ (Target Water Quality). Regarding the monthly flow rate variation, the five sites showed the distribution of the lowest flow rate between May and June, indicating a high probability of dry weathering of the streams. The variation of water quality confirmed the vulnerable timing of flow rate in each site, and it is therefore deemed necessary to plan to reduce T-P and TOC. A comparison and evaluation of TWQ showed that there was a difference between the TWQ values achieved by the two techniques. In addition, the margin ratio to the 50% excess ratio can be found in the LDC evaluation. The results of the LDC evaluation by section and by month showed whether or not the water quality was exceeded by flow conditions, along with the vulnerable sections and timing. Accordingly, it is judged that this method can be used for water quality management in TMDLs (Total Maximum Daily Loads). |