• 환경영향평가
• /
• 제8권1호
• /
• pp.41-49
• /
• 1999

This study was carried out to estimate the runoff loading characteristics of the non-point source pollutions in the Youngsan river basins by the method of land-use types and rainfall. The lysimeter test, rainfall and stream flowmeter measurement were performed to develop the pollutant loading unit discharged from the non-point sources. As the non-point sources, the unit pollutant discharge rates were different from the land-use types such as paddy field, upland, forest, housing site and others. The pollutant loading units classified by land-use types in the Youngsan river basins are as follows: The total BOD loading rate is 15.3 ton/day and the housing site is discharged 50.6%, the total T-N loading rate is 6.0 ton/day and the paddy field and upland is discharged 77.6%, and the total T-P loading rate is 0.39 ton/day and the paddy field and upland is discharged 81.2%. The pollutant loadings by rainfall in the Youngsan river basins are about 7,425 ton/year of BOD, 324 ton/year of T-N and 118 ton/year of T-P, respectively.

• 한국농공학회논문집
• /
• 제55권1호
• /
• pp.17-29
• /
• 2013

Long-Term Hydrologic Impact Assessment (L-THIA) model which is a distributed watershed model was applied to analyze the spatial distribution of surface runoff and nonpoint source pollutant loading from Imha watershed during 2001~2010. L-THIA CN Calibration Tool linked with SCE-UA was developed to calibrate surface runoff automatically. Calibration (2001~2005) and validation (2006~2010) of monthly surface runoff were represented as 'very good' model performance showing 0.91 for calibration and 0.89 for validation as Nash-Sutcliffe (NS) values. Average annual surface runoff from Imha watershed was 218.4 mm and Banbyun subwatershed was much more than other watersheds due to poor hydrologic condition. Average annual nonpoint source pollutant loading from Imha wateshed were 2,295 ton/year for $BOD_5$, 14,752 ton/year for SS, 358 ton/year for T-N, and 79 ton/year for T-P. Amount of pollutant loading and pollutant loading rates from Banbyun watershed were much higher than other watersheds. As results of analysis of loading rate from grid size ($30m{\times}30m$), most of high 10 % of loading rate were generated from upland. Therefore, major hot spot area to manage nonpoint source pollution in Imha watershed is the combination of upland and Banbyun subwatershed. L-THIA model is easy to use and prepare input file and useful tool to manage nonpoint source pollution at screening level.

• 한국습지학회지
• /
• 제8권4호
• /
• pp.33-40
• /
• 2006

The water of rivers and lakes in Korea is the main sources for drinking, industrial and agricultural purposes. However, various pollutants washed-off from watershed area make worse and worse the water quality. Particularly, the changes of land uses in watershed area is the main pollutant sources in many cases in Korea, it is usually called to nonpoint pollution sources. In this reason, the Ministry of Environment are programing the total maximum daily load for four major large rivers in order to improve the water quality by controlling the watershed area. Therefore, this research was performed to estimate the total pollutant input from watershed areas to lakes of Ganwol and Boonam located in Chungnamdo. The AGNPS water quality model and monitoring were used to estimate the pollutant loading rates with unit pollutant concentration of each land use. The main landuse of the research area are forest, wet and dry paddy field and small urban area. The research shows that the pollutant sources in Ganwol and Boonam lakes are from the various landuses. In this manuscripts, the results will provide important informations for mitigating the pollutants to the lakes.

• 한국물환경학회지
• /
• 제22권2호
• /
• pp.314-320
• /
• 2006

Diffuse pollution from an urban area contributes to the significant pollution loading to a receiving water body. In this paper, rainfall runoffs from an urban basin with combined sewer systems located in the city of Daejeon were monitored to measure the rainfall runoff discharge rates and pollutant concentrations. Strong first flush effects were observed for all monitored rainfall runoffs. The first flush effects were closely related to rainfall intensity, while suspended solids were closely related to pollutant constituents. The observed averaged Event Mean Concentrations (EMCs) of Combined Sewer Overflows (CSOs) were 536.1 mg SS/L, 467.7 mg CODcr/L, 142.7 mg BOD/L, 16.5 mg TN/L, and 13.5 mg TP/L. Storage volumes for containing the first flush to improve water quality of the receiving stream can be estimated based on suspended solid concentration. In this study, retainment of the first flush equivalent to 5mm of precipitation could reduce diffuse pollution loading induced by CSOs to a receiving water body by up to 80% of suspended solid loading.

• 상하수도학회지
• /
• 제32권3호
• /
• pp.221-233
• /
• 2018

Two climate change scenarios, the RCP (Representative Concentration Pathways) 4.5 and the RCP 8.5 in the fifth Assessment Report (AR5) by Intergovernmental Panel on Climate Change (IPCC), were applied in the Yocheon basin area using the SWAT (Soil and Water Assessment Tool) model to estimate changes in flow rates and pollutant loadings in the future. Field stream flow rate data in Songdong station and water quality data in Yocheon-1 station between 2013~2015 were used for model calibration. While $R^2$ value of flow rate calibration was 0.85 and $R^2$ value of water qualities were in the 0.12~0.43 range. The total study period was divided into 4 sub periods as 2030s (2016~2040), 2050s (2041~2070) and 2080s (2071~2100). The predicted results of flow rates and water quality concentrations were compared with results in calibrated periods, 2015s (2013~2015). In both RCP scenarios, flow rate and TSS (Total Suspended Solid) loadings were estimated to be in increasing trend while TN (Total Nitrogen) and TP (Total Phosphorus) loadings showed decreasing patterns. Also, flow rates and pollutant loadings showed larger differences between the maximum and the minimum values in RCP 4.5 than RCP 8.5 scenarios indicating more severe effect of drought and flood, respectively. Dependent on simulation period and rainfall periods in a year, flow rate, TSS, TN and TP showed different trends in each scenario. This emphasizes importance of considerations on time and space when analyzing climate change impacts of each variable under various scenarios.

• 한국습지학회지
• /
• 제9권2호
• /
• pp.9-20
• /
• 2007

환경부에서 국내 4대강에 도입한 수질오염총량관리제는 점오염원뿐만 아니라 비점오염원의 관리를 통해 주요 상수원수인 4대강의 수질을 개선하고자 함이다. 비점오염원의 주요 근원은 토지이용이며, 개발사업은 토지이용의 변화를 의미하고 비점오염물질의 유출 증가를 의미한다. 따라서 본 연구는 현재 국내에서 유일하게 수질 오염총량관리제가 도입되어 개발할당량이 주어져 있는 한강수계의 리조트 개발사업에서 개발계획에 따른 토지이용의 변화와 더불어 유출이 증가하는 비점오염물질의 양을 산정함으로써 효율적인 비점오염원 관리방안을 수립하고자 한다. 이러한 목적을 달성하기 위하여, 개발사업 전후의 토지이용에 따른 비점오염물질의 발생 및 배출부하량 변화를 산정하였으며, 이를 근거로 비점오염물질 유출 관리가 요구되는 토지이용을 선정하였다. 또한 그 결과를 이용하여 적정 비점오염물질 관리방안(최적관리방안)을 수립하고자한다.

• 상하수도학회지
• /
• 제25권6호
• /
• pp.949-957
• /
• 2011

This aim of study was to investigate the characteristics of discharge of pollutants as well as the correlation between flow rate and water quality constituents in a combined sewer system according to the characteristics of rainfall. For the loading rates for each pollutant, the median concentrations of all pollutants except T-N was increased when a CSO took place. The loading rates of BOD, COD, SS, T-N, T-P, Cu and Zn at the CSOs were 328-1255, 25-129, 83-2009, 4-12, 14-51, 5-11 and 5-13 times higher than the DWF (Dry Whether Flow), respectively. Especially, SS loading rate was found to be highest in all pollutants. On the other hand, the range of the first flush coefficient, b for water quality constituents such as BOD, COD, SS, T-N, T-P, Cu and Zn were 0.537-0.878, 0.589-0.888, 0.516-1.062, 0.852-1.031, 0.649-0.954, 0.975-1.015 and 0.900-1.114, respectively. In term of correlation between flow rate and pollutant concentrations, SS concentration was highly correlated to flow rate. However, there was an inverse correlation between EC (Electrical Conductivity) and flow rate because of the high dilution of flow rate. In case of correlation between pollutants, there was a high correlation between SS and T-P.

• 한국물환경학회지
• /
• 제20권6호
• /
• pp.631-640
• /
• 2004

This research was conducted to understand the magnitude and nature of the stormwater emissions with the goal of quantifying stormwater pollutant concentrations and mass emission rates of pollutants. Eight highway sites in Southern California area were monitored for three years with collecting of grab and flow-weighted composite samples, rainfall and runoff flow. Generally the EMCs cannot be determined by simple statistical averaging of measured pollutant concentrations because of random characteristics of runoff quality and quantity. Therefore, this manuscripts will show a new EMC determination method. The EMC ranges of 95% confidence intervals are 102.78-216.37mg/L for TSS, 104.53-251.79mg/L for COD, 5.42-10.58mg/L for oil & grease and 2.42-10.18mg/L for TKN. The ranges of washed-off mass loading are determined to $0.06g/m^2-17.27g/m^2$ for TSS and $0.1-3.23g/m^2$for COD.

• 한국물환경학회지
• /
• 제20권5호
• /
• pp.415-421
• /
• 2004

Litter wastes on highway runoff are gradually being considered one of the major pollutants of concern in protecting the integrity of receiving waters for beneficial use. The California State Water Resources Control Board has identified in their 303(d) list at least 36 water bodies where trash or litter is considered a pollutant of concern. The first TMDL adopted by the Region 4 (Los Angeles area) of the California State Water Quality Control Board was for trash in the Los Angeles River. The first flush characteristic study was developed to obtain first flush water quality and litter data from representative stormwater runoff from standard highway drainage outfalls in the Los Angeles area. Total captured gross pollutants in stormwater runoff were monitored at six Southern California highway sites over two years. The gross pollutants were 90% vegetation and 10% litter. Approximately 50% of the litter was composed of biodegradable materials. The event mean concentrations show an increasing trend with antecedent dry days and a decreasing trend with total runoff volume or total rainfall. Event mean concentrations were ranged 0.0021 to 0.259g/L for wet gross pollutants and 0.0001 to 0.027g/L for wet litters. The first flush phenomenon was evaluated and the impacts of various parameters such as rainfall intensity, drainage area, peak flow rate, and antecedent dry period on litter volume and loading rates were evaluated. First flush phenomenon was generally observed for litter concentrations, but was not apparent with litter mass loading rates. Litter volume and loading rates appear to be directly related to peak storm intensity, antecedent dry days and total flow volume.

• 한국습지학회지
• /
• 제8권4호
• /
• pp.23-31
• /
• 2006

환경부에서 국내 4대강에 도입한 수질오염총량관리제는 점오염원뿐만 아니라 비점오염원의 관리를 통해 주요 상수원수인 4대강의 수질을 개선하고자 함dl다. 비점오염원의 주요 근원은 토지이용이며, 개발사업은 토지이용의 변화를 의미하고 비점오염물질의 유출 증가를 의미한다. 따라서 본 연구는 수질오염총량관리제가 도입되어 있는 한강수계의 리조트 개발사업에서 개발계획에 따른 토지이용의 변화와 더불어 유출이 증가하는 비점오염물질의 양을 추정함으로써 관리방안을 수립하고자 한다. 이러한 목적을 달성하기 위하여, 개발사업 전후의 토지이용에 따른 비점오염물질의 발생 및 배출 부하량 변화를 산정하였으며, 이를 근거로 비점오염물질 유출 관리가 요구되는 토지이용을 선정하였다. 또한 그 결과를 이용하여 적정 비점오염물질 관리방안(최적관리방안)을 수립하고자 한다.