The purpose of this research was to suggest the water quality improvement in streams by evaluating the distribution characteristics of organics and ammonia nitrogen discharged by pollution sources from human living. The public sewage treatment plants'(PSTPs) effluents and the waters from streams in Gyeonggi-do were sampled and analyzed. Nitrogenous oxygen demand (NOD) was measured for the stream waters as well as the PSTPs effluents, and the correlations of NOD and NH3-N, NH3-N and water temperature in the PSTPs effluents were confirmed. In the case of the stream waters, the ratios of NOD to BOD and NH3-N increased in the downstream sites after discharging the PSTPs effluents. As a result of statistical analysis of NH3-N concentrations for the national water quality monitoring streams in Gyeonggi-do, NH3-N showed the non-normal distribution which were biased to the left, but showed the considerable level because of higher coefficient of variation. Therefore, it is required to establish the water quality standard for the NH3-N as a new parameter for judging the quality of the streams. In addition, inducing complete nitrification and introducing a logical standard setting system are needed to improve the water quality of streams by identifying distribution of the nitrogen components from PSTPs effluents.

No abstract