• Journal of Korean Society of Water and Wastewater
• /
• v.26 no.3
• /
• pp.479-486
• /
• 2012

Runoff characteristics of pollutant loads of the lower Han River was studied before full implementation of Total Pollution Load Management System(TPLMS). Magnitude of macroscopic(annual) fluctuation was in the order of Namhan River > Han River > Bukhan River, gross weight TP > gross weight TN > gross weight BOD, gross weight deviation > concentration deviation. Flux variation was higher than that of concentration. Microscopic(weekly) fluctuation showed similar pattern to macroscopic scale. TP showed the highest deviation resulting in the lowest reliability. 60% of annual flux passed during summer 3months resulting in 43-46% pass of gross weight at the lower Han River. Strong correlation was found between flux and gross weight especially in gross weight TN. Gross weight pollution increased as high as 400% while passing Seoul area due to the concentration. The deviation from moving average increased during summer season in the gross weight TP and BOD. Seasonal tendency was confirmed especially in gross weight TN and TP using autocorrelation function.

• Journal of Korean Society on Water Environment
• /
• v.23 no.1
• /
• pp.161-168
• /
• 2007

The main aim of this work is focus on the Geum river water quality evaluation of pollution data obtained by monitoring measurement during the period 2001-2005. The complex data matrix 19 (entire monitoring stations)*13 (parameters), 60 (month)*13 (parameters) and 20 (season)*13 (parameters) were treated with different multivariate techniques such as factor analysis/principal component analysis (FA/PCA). FA/PCA identified two factor (19*13) classified pollutant Loading factor (BOD, COD, pH, Cond, T-N, T-P, $NH_3$-N, $NO_3$-N, $PO_4$-P, Chl-a), seasonal factor (water temp, SS) and three Factor (60*13, 20*13) classified pollutant Loading factor (BOD, COD, Cond, T-N, T-P, $NH_3$-N, $NO_3$-N, $PO_4$-P), seasonal factor (water temp, SS) and metabolic factor (Chl-a, pH). Loadings of pollutant factor is potent influence main factor in the Geum river which is explained by loadings of pollutant factor at whole sampling stations (71.16%), month (52.75%) and season (56.57%) of main water quality stations. Result of this study is that pollutant loading factor is affected at Gongju 1, 2, Buyeo 1, 2, Gangkyeong, Yeongi stations by entire stations and entire month (Gongju 1, Cheongwon stations), April, May, July and August (buyeo 1) by month. Also the pollutant Loading factor is season gives an influence in winter (Gongju 1, buyeo 1) from main sampling stations, but Cheongwon characteristic is non-seasonal influenced. This study presents necessity and usefulness of multivariate statistic techniques for evaluation and interpretation of large complex data set with a view to get better information data effective management of water sources.

• Korean Journal of Ecology and Environment
• /
• v.40 no.4
• /
• pp.503-510
• /
• 2007

The purposes of the study were to analyze the seasonal effects on the fish fauna and compositions including trophic guilds and tolerance guilds. For the study, we collected fish samples twice in June as premonsoon period and early September 2007 as monsoon periods in five sampling sites of the Gap Stream, and then biological oxygen demand (BOD), nutrients (TN, TP) and suspended solids (SS) were compared with the guild data along the gradient of upstream-to-downstream. Chemical water quality, based on BOD, TP, and TN degraded gradually from the upstream to downstream reach and there were about 3 fold difference between S1 and S5. Water quality was worse in the premonsoon than the monsoon, and the heavy monsoon resulted in a dilution of the polluted river by rain water, especially, in the downstream reach. Total number of fish species, based on the catch per unit effort (CPUE), showed a distinct difference between the two seasons; 30 species were sampled in premonsoon, but 23 species were sampled in the monsoon, indicating a seasonal difference in the fish fauna. Tolerant species dominated the fish community (48.3%) in the stream, and the proportions prior to physical disturbance by the monsoon rain were evidently greater in the downstream reach than the upstream. This reflected the characteristics of urban stream polluted by nutrient enrichment as shown in the BOD and TP values. Sensitive species in the premonsoon decreased from the gradient of upstream-to-downstream reach. Such seasonal modifications in the trophic and tolerance guilds were evident. In the analysis of trophic guild and habitat guild, during the premonsoon the proportion of insectivore and riffle-benthic species were largely greater in the upstream reach than the downstream, whereas the proportions were opposite along the gradient of the stream in monsoon. Thus, the patterns of chemical water quality along the longitudinal gradients reflected the premonsoon conditions of insectivores and tolerant species, indicating that summer monsoon data of fish may not match with water quality due to large physical disturbance by flow regime. Seasonal monsoon in this region as well as the chemical pollution may act as a key role influencing the fish compositions of trophic and tolerance guilds and fauna. The data collected during the premonsoon rather than the monsoon, thus, may be better predictor for a diagnosis of stream health conditions.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.8
• /
• pp.3726-3734
• /
• 2012

This study evaluated the behavior of pollutants based on the seasonal change by selecting the branch river's factors that influence the outflow of pollutants in Soyang lake basin. The analysis method was the factor analysis that classified the factors of the drainage area influencing the outflow of pollutants, and evaluated selected representative factors. As a result of the study, SS and T-P factors should be classified as similar factors to the storm water runoff, and the improvement of water must be strived through managing source of pollution at the time of no rain. Second, as the result of the influence from the factors, spring and winter seasons usually exert 36% influence and summer and fall exert over 90% significant influence that the improvement of water through managing source of water seems possible. At last, the prediction about delivery pollution load considering the outflow characteristic of pollutants at the drainage area based on seasonal change by regarding selected factors as independent variables is possible.

• Korean Journal of Environmental Agriculture
• /
• v.39 no.3
• /
• pp.197-203
• /
• 2020

BACKGROUND: Most lakes have increased concerns about water pollution due to the inflow of non-point sources caused by human activities. Therefore, the lake water quality survey was conducted in order to propose effective plans for water quality management by analyzing the characteristics of lakes and the change of water quality. METHODS AND RESULTS: In order to investigate the physicochemical water quality in Daedong lake, water quality analysis was undertaken from July 2018 to June 2019. Water temperature was ranged from 7.8 to 34.3℃ and pH varied from 6.9 to 10.2. The concentration of Dissolved oxygen, Suspended solid, Biochemical Oxygen Demand (BOD), and Chemical Oxygen Demand (COD) were 5.6 ~ 17.2 mg/L, 2.4 ~ 35.3 mg/L, and 4.5 ~ 15.1 mg/L, and 0.9 ~ 2.8 mg/L, respectively. The Total Nitrogen (T-N) concentration ranged from 0.974 ~ 2.126 mg/L, and Total Phosphorus (T-P) concentration ranged from 0.014 ~ 0.057 mg/L. The Chlorophyll-a (Chl-a) ranged from 2.7 ~ 37.9 mg/㎥. Through Carlson TSIm assessment using T-P and Chl-a results, evaluating trophic state, Daedong lake was evaluated as mesotrophic. CONCLUSION: Water pollution management plan needs such as nutrient removal technology and nonpoint source management for prevention of eutrophication in Daedong lake.

• Membrane and Water Treatment
• /
• v.10 no.5
• /
• pp.339-352
• /
• 2019

Long term water quality change was analyzed to evaluate the effect of the Total Maximum Daily Load (TMDL) policy. A trend analysis was performed for biochemical oxygen demand (BOD) and total phosphorus (TP) concentrations data monitored at the outlets of the total 41 TMDL unit watersheds of the Nakdong River in the Republic of Korea. Because water quality data do not usually follow a normal distribution, a nonparametric statistical trend analysis method was used. The monthly mean values of BOD and TP for the period between 2004 and 2015 were analyzed by the seasonal Mann-Kendall test and the locally weighted scatterplot smoother (LOWESS). The TMDL policy effect on the water quality change of each unit watershed was analyzed together with the results of the trend analysis. From the seasonal Mann-Kendall test results, it was found that for BOD, 7.8 % of the 41 points showed downward trends, 26.8 % and the rest 65.9% showed upward and no trends. For TP, 51.2% showed no trends and the rest 48.8% showed downward trends. From the LOWESS analysis results, TP began to decrease in most of the unit watersheds from mid-2010s when intensive chemical treatment processes were introduced to existing wastewater treatment plants. Overall, for BOD, relatively more points were improved in the main stream compared to the points of the tributaries although overall trends were mostly no trend or upward. For TP, about half of the points were improved and the rest showed no trends.

• Journal of Korean Society of Water and Wastewater
• /
• v.21 no.2
• /
• pp.225-233
• /
• 2007

Road runoff water is one of the non-point sources (NPSs) of pollution negatively influencing drinking water source. Numerous road runoff NPS waters have been studied for over the last decade. However, the sources of pollution can be conditional, seasonal, or accidental. Therefore, measurement of pollutant loadings in different site is necessary to estimate the effect of road runoff water. The objective of this study was to examine the quality of road runoff water from a city bridge in Seoul, Korea. This study was conducted for two years to assess annual discharge pollution loads. In this study, key water quality parameters including chemical oxygen demand ($COD_{Cr}$), biochemcial oxygen demand ($BOD_5$), total nitrogen (T-N), total phosphorus (T-P), and suspended solid (SS) were measured at 18 different events. The results showed that typically the pollutant concentrations are higher at the beginning of each event and decrease afterwards. The first 20% of the volume of the runoff from each event is transporting 46% ($COD_{Cr}$), 48% ($BOD_5$), 50% (T-N), 34% (T-P), 30% (SS), respectively. The event mean concentrations (EMCs) were $COD_{Cr}$ (199 mg/L), $BOD_5$ (41.2 mg/L), T-N (7.97 mg/L), T-P (0.42 mg/L) and SS (113 mg/L). Although the results were consistent with the previous study (Barbosa and Hvitved-Jacobsen, 1999), $COD_{Cr}$, $BOD_5$, T-N exhibit a stronger first flush effect compared to the other contaminants.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1995.10a
• /
• pp.94-100
• /
• 1995

In recent years it has become necessary to design water management system to minimize water consumption as well as satisfy more stringent environmental requirements. This is mainly due to the seasonal water shortage and environmental problems on water pollution that have taken place at many industrialized regions in Korea. Accordingly, membrane technology in Korea is finding increasing application in the water industry because it has been found to be effective and economic treatment method compared with conventional technology. The membrane processes with the greatest potential for water and wastewater treatment are microfiltration(MF), ultrafiltration(UF), nanofiltration(NF) and reverse osmosis (RO), which utilize pressure differentials.

• 한국해양학회지
• /
• v.3 no.2
• /
• pp.47-54
• /
• 1968

Monthly mean values for EDTA hardness in the Han River water were determined for March 1966 through May 1967. The hardness was retained a range of 22-59 mg/L the maximum value of 59 mg/L was approached in the months of mid-winter, indicating a seasonal variation. The annual ranges of Ca and Mg were 3.7-9.1 mg/L, 1.5-10.4 mg/L, respectively. The annual range of Mg:Ca ratio was 0.18-2.60. And the hardness correlated closely with Mg volume. In Korea, fortunately, most river waters are not yet suffering from damaging pollution. We must try to establish our water quality criteria based on scientific data, and make research recommendations for the following water uses; public water supplies, aquatic life and wildlife, industry, recreation and aesthetics.

• Journal of Korean Society on Water Environment
• /
• v.37 no.1
• /
• pp.20-31
• /
• 2021

In this study, an analysis of the characteristics of organic matter and nitrogenous oxygen demand (NOD) of 17 sewage effluent and wastewater treatments was conducted. High CODMn and carbonaceous biological oxygen demand (CBOD) concentrations were observed in the livestock treatment plants (LTP), wastewater treatment plants(WTP), and night soil treatment plants (NTP), but the highest NOD concentration and contribution rates of NOD to BOD5 were found in sewage treatment plants (STP). There was no significant difference in the CBOD/CODMn ratio for each of the six pollution source groups, but the LTPs, WTPs, and NTPs all showed relatively high CODMn concentrations in their effluent samples, indicating that they are facilities which discharge large amounts of refractory organic matter. The seasonal change of NOD in all facilities' effluent was found to be larger than the seasonal change of CBOD, and data results also revealed an elevation of NOD and NH3-N concentration from December to February, when the water temperature was low. There was no significant difference in NH3-N concentration in relation to pollution source group (p=0.08, one-way ANOVA), but the STP, which had a high NOD contribution rate to BOD5 of 48%, showed a high correlation between BOD5 and NOD (r2=0.95, p<0.0001). These results suggest that the effect of NOD on BOD5 is an important factor to be considered when analyzing STP effluent.