The watershed of Gohyeon Stream was divided into the 10 sub-basins, and 19 sampling points were
selected in their tributaries, which the characteristics of the water quality and pollution loads variance were
investigated for during the rainy and dry seasons. The results of water quality analysis revealed that the upper
watershed(T1~T8) of Gohyeon Stream had a feature of rural area, and its lower watershed(T9~T19) had a feature
of the municipal area. The non-point pollution loads of the tributaries were estimated with 2,063, 601, 365, and 45
ton/yr of SS, COD, DIN, and DIP, respectively. The pollution loads of the parameters except DIP were generated
about 60% during the rainy season, which suggested that a precipitation significantly influenced on the discharge of
non-point source pollution. Meanwhile, the non-point pollution load of DIP was generated about 60% during the
ordinary and dry seasons, which suggested that control of a phosphorus pollution source was significantly required
during these seasons. Pearson's correlation analysis revealed that SS pollution source of the upper watershed was
definitely different from that of the lower watershed, that is, the pollution load from the upper watershed was
mainly caused by the discharge of SS due to soil erosion in the farmland and forest land during the rainy season,
and that of the lower watershed by the discharge of sewage and municipal run-off.