• Journal of Wetlands Research
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• v.20 no.4
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• pp.304-313
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• 2018

Agricultural land reclamation in Saemangeum tidal land project is mostly planned to be completed by 2020. Irrigation water for the land is required to be prepared by that time. However, water quality for the irrigation sources is barely meet the target concentration. This paper described the reduction effect of and policy consideration for best management practices (BMPs) which were fertilizer prescription by soil test (SO#1), mixed application of SO#1 and 3 (SO#2), drainage gate control (SO#3), time-release fertilizer application (SO#4), and control (CT). Reduction of paddy runoff was relatively higher in SO#3 (25%) and SO#1 (27%) while lower in SO#4 (9%) and SO#2 (7%) than that in CT. In addition, farmers promised to follow the BMP guidelines but they didn't because of the several problems caused for the BMPs implementation. Thus, it recommended developing an automated control of irrigation gate and paddy water depth and supporing farmers for NPS pollution control and irrigation water reduction.

• Journal of Wetlands Research
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• v.21 no.2
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• pp.173-180
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• 2019

This study was conducted to understand factors affecting TSS and heavy metals transport on the road, parking lot and roof. During storm events, heavy metals, which were mostly attached to TSS, were also transported when TSS was washed off in the road, parking lot and roof. This finding may be supported by the significant correlations between TSS load and total and soluble heavy metals load including Cr, Fe, Cu, and Pb (Pearson r value: 0.52 to 0.73; probability p value<0.01). Generation and transport of TSS and heavy metals were greater in the road and parking lot compared to the roof due to vehicular activities, slope and greater catchment areas of these sites. It was found that TSS transport during peak flows of storm events ranges from 65% to 75% implying that by controlling peak flows, TSS transportation to nearby water bodies may be decreased. Depending on the target TSS and heavy metal reduction, sizing of low impact development (LID) technologies and green infrastructures (GI) such as infiltration trench, tree box filter, and rain garden may be calculated. Future researchers were recommended to assess the limitations of the systems and determine the design considerations for these types of facilities.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.48-48
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• 2011

본 연구에서는 미래 기후변화가 하천 및 호소수질에 미치는 영향을 평가하고자 유역 수문-수질 모의가 가능한 SWAT(Soil and water assessment tool) 모형과 호소수질 모의가 가능한 WASP(Water Quality Simulation Program) 모형을 연계운영하여 충주호를 포함하는 충주댐 유역($6,642.0km^2$)에 적용하였다. 이를 위해 IPCC(Intergovernmental panel on climate change)에서 제공하는 A1B 배출시나리오를 포함하는 MIROC3.2 hires 모형의 결과로부터 충주댐 유역의 총 6개 기상관측소에 대한 과거 30년(1997~2006) 실측자료를 바탕으로 미래 온도와 강수에 대한 편이보정(Bias correction) 및 Change Factor Method로 상세화(Downscaling)하여 미래 기후자료(2020s, 2050s, 2080s)를 생산하였다. 미래 연평균 온도는 기준년도인 2000년에 비해 최대 $+4.8^{\circ}C$(2080s)의 온도증가를 보였으며, 강수량의 경우 여름과 가을 강수량이 다소 감소하였으나 연평균 강수량은 최대 +34.4%(2080s) 증가하는 것으로 전망되었다. 먼저, SWAT 모형을 이용한 기후변화에 따른 댐 유입량은 39.8%(2080s) 증가는 것으로 분석되었으며 유역의 유출특성 변화로 인한 유사량은 지표유출변화에 기인하여 봄과 겨울에 증가하는 경향과 함께 -14.5%(2020s) ~ +27.3%(2080s)의 변화를 보이는 것으로 분석되었다. 영양물질에 대한 오염부하량은 2080s에서 T-N이 증가추세를 보이며 최대 87.3% 까지 증가하는 반면, T-P는 유사량과 유사한 변화패턴을 보이며 최대 48.4%까지 감소하는 것으로 분석되었다. 호소수질 모델링을 위한 충주호의 Segment 구성은 충주댐1 지점에서부터 충주댐4 지점까지 전체 수표면적 $65.7km^2$에 대하여 상층과 하층 총 760개로 구성하였으며, SWAT 모형에 의한 충주호 유입하천 소유역에서의 미래 유출 및 영양물질 자료를 WASP 모형의 초기값으로 입력하여 수체 내의 BOD, Chl-a, T-N, T-P 변화 분석을 실시하였다. 이와 같이 지구 온난화에 의한 기후변화는 강우특성 변화에 따른 가뭄과 홍수 등 극한 기상현상의 발생, 유역 물순환 체계 변화를 야기 시키므로서 수자원 부존량 변화에 영향을 미칠 뿐만 아니라 기온상승에 따른 수온변화, 비점오염물질의 거동에도 변화를 초래하여 하천 및 호소 수질에 큰 영향을 미칠 것으로 판단된다.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.210-215
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• 2004

The Purpose of this study are to develop the simulation(Tank model, Rainfall-runoff model) for the estimation of wily river discharge and for evaluation of wily pollutant loads from the watersheds of the objected basin area. As apply this constructed Tank model to Nakdong river region, we evaluated the wily river discharge of Nakdong river from use-land conditions, precipitation and evaporation data of 3 years(from 1998 to 2000) and investigate the seasonal fluctuation of SS, COD, TN, TP inflowing into Nakdong river. The result shows that summer has high pollutant level than winter in seasonal characteristic and the down stream has high pollutant level than the upper stream. The annual average of SS, COD, TN, TP flawing in Nakdong river(Samranjin) was estimated each 691ton-COD/year, 1854.2ton-SS/year, 382.8ton-TN/year and 13.0ton- TP/year.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.30-33
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• 2001

This study was carried out to estimate the runoff pollutant loadings for water quality management in Boryung freshwater reservoir watershed. The hydrological monitoring system were operated for water level measurement during $1999{\sim}2000$ and temporal variation of water quality constituents such as pH, EC, total nitrogen, total phosphorus were analysed, periodically. Monthly runoff volumes by TANK model and potential pollutant loadings calculated by unit method were compared with measured values.

• Journal of Korean Society of Rural Planning
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• v.9 no.1 s.18
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• pp.77-83
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• 2003

This study was carried out to provide the basic information for the water quality management of the Sumjin River Basin. The Chooryeongchon stream watershed was selected and the parameters representing water quality were investigated from May 1999 to September 2002, periodically. Yearly mean runoff ratio to the rainfall amount of the watershed was analysed as $26.6{\sim}58.8%$. Temporal variation of water quality constituents such as water temperature, pH, EC, total nitrogen, total phosphorus were analysed. The result showed that pH ranged $5.7{\sim}7.7$, EC $54{\sim}167\;{\mu}S/cm$, COD $0.8{\sim}18.1\;mg/L$, respectively. Total-N and total-P concentration ranged from 0.89 to 5.19 mg/L and from 0.0004 to 0.030 mg/L, respectively. The relationships between runoff and mass load were derived and showed high linear relationships.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1393-1397
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• 2005

홍수유출을 저감시키기 위해서 유역의 저류기능을 강화시킬 수 있는 댐 건설은 이수적인 측면에서 안정적인 용수공급을 보장해주는 수단으로 겸용되어 왔으며, 특히 다목적댐이 건설되면서 하도의 첨두홍수유출량을 줄이는데 크게 기여해 왔다. 하지만 그로 인해 물의 흐름이 막히는 정체수역이 증가하고 있으며, 생활오수, 산업폐수의 발생은 정체수역에서의 영양염류 부하량을 증가시켜 부영양화를 초래하고 있다. 수생식물은 태양빛을 받아 광합성 작용을 하여 수중에서 성장하면서 수중의 유$\cdot$무기물질을 영양소로 섭취함으로써 수질을 정화시키는 작용을 하게 된다. 영양염류 부하량이 큰 정체수역의 오염된 물은 식물의 성장활동에 의해서 어느 정도 정화시킬 수 있으며, 이와 같이 수중에 식물을 식재하기 위해서는 식물이 하상에 쉽게 그리고 지속적으로 성장하고 번식활동을 할 수 있는 여건이 필요하다. 따라서 본 연구에서는 Mattress/Filter를 정체수역에 설치함으로써 이러한 식물의 성장과 번식을 도와줄 수 있는 환경조건을 제안하였다. 연구결과, Mattress에 식재한 갈대, 줄 및 애기부들의 피도는 $60-80\%$ 정도로 나타났다. 각 Mattress의 식물군집에는 초기 식재한 식물의 우점도가 가장 높았으나 갈대와 줄 군락의 경우 다른 종이 많이 출현하는 것으로 나타났다. 갈대 군락에서는 갈대가 크게 우점하였으나 그 외에 돌피, 하늘지기, 여뀌바늘 등이 우점하는 것으로 나타났다. 또한 줄 군락에서는 역시 줄이 크게 우점하였으나 방동사니, 돌피, 조개풀 등이 출현하였다. 애기부들 군락에서는 애기부들외에 세모고랭이와 미국가막사리 두가지 종만 출현한 것으로 나타났다. 갈대와 줄 군락의 출현 종수는 각각 7과 11이었으며, 다양도지수가 1.67, 2.18로 식물다양성이 크게 증가한 것으로 나타났다. 수질은 BOD 10mg/L, TN 15mg/L, TP 2.0mg/L이하로 이를 유등천 상류부에 공급할 경우 유등천의 수질은 BOD 6.7mg/L, TN 9.80mg/L, TP 0.90mg/L를 나타낼 것으로 예측된다. 고도처리시설의 도입 후 금강 합류점에서 갑천의 예측 BOD는 7.4mg/L로 현재 9.0mg/L에 비하여 개선되지만 이는 금강수계 오염총량 관리계획의 시$\cdot$도 경계지점 목표수질인 5.9mg/L를 만족시키지 못하므로, 이를 만족시키기 위해서는 방류수 BOD 7.2mg/L이하로 처리해야 할 것으로 판단된다.which support only concepts or image features.방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$로 나타났다.천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술적 교정을 해줌으로써 좋은 성적을 기대할 수 있음을 보여주었다.특히 교사들이 중요하게 인식하는 해방적 행동에 대한 목표를 강조하여 적용할 필요가 있음을 시사하고

• Journal of Korea Water Resources Association
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• v.31 no.6
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• pp.709-725
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• 1998

The characteristics of storm and water quality are investigated based on the measuring data of the test river, the Hongje. the water quality of the test river is generally good comparing to other urban rivers in Seoul, because of the interception of sewer flow. But this system makes the river dry up for 3-4 months in winter. On the other hand, in rainy period the storm from the combined sewer system causes rapid increasing pollutants loads. In order to simulate the urban storm and water quality of the trest basin, the models such as SWMM, ILLUDAS, STORM, HEC-1 were applied and the results are compared in its applicability and accuracy aspects. All models discussed here have shown good results and it seems that SUMM is the most effective model in simulating both quantity and quality. Also, regression relations between the water quantity and quality were derived and their applicabilities were discussed. This regression model is a simple effective tool for estimating the pollutant loads in the rainy period, but if the amount of discharge is bigger than measuring range of raw data, the accuracy becomes poor. This model could be supplemented by expanding the range of collecting data and introducing the river characteristics. The HEC-1 would be anther effective model to simulate storm runoff of a river basin including urban area.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.3
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• pp.152-158
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• 2015

This paper investigated the membrane fouling potential at the state of passive adsorption which is no permeation with the test modules on COD (Chemical oxygen demand) loading rates, examined the recovery rate and resistance on membrane fouling by three cleaning manners of hydrophobic membrane in a bioreactor. The results showed that high COD loading led to the increase of extra-cellular polymeric substances and filtration resistance. The permeability resistance from 1st day to 63rd day was getting increased, however, the value of permeability resistance after 63th day during the operation period was almost same level at three COD loading rates, it was due that the biomass adhesion on membrane surface at the state of passive adsorption reached to the critical state. Also, the final recovery rates after three cleaning manners were 78%, 72% and 69% at the COD loading concentrations of 250 mg/L, 500 mg/L and 750 mg/L respectively, and then recovery rate by physical cleaning at Run 2 and Run 3 was decreased after 40th day, it proved that biomass cake, which is not easily removed, was formed on the membrane surface because of high COD loading rate and EPS concentration.

• Journal of Korea Water Resources Association
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• v.36 no.4
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• pp.521-531
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• 2003

Pollutant load to Yongdam Reservoir considering rainfall effect is estimated using data collected during dry and wet days between Dec 1998 and Oct. 1999. Limit of significant rainfall was assumed to be as 10 mm/day and numbers of days of significant rainfall for each month were counted using 10 years of meteorological data of the study area. Water quality input concentrations were estimated by taking weighted averages of concentrations in dry and wet days in each month. The resulting concentrations were used as inputs for water quality modeling of Yongdam Reservoir. When rainfall effect was included average reservoir concentrations of BOD, TN and TP were increased by 70％, 5％ and 27％, respectively Considering the fact that Korea is under the significant influence of monsoon effect during the summer, it should be important to include rainfall effect in estimating pollutant input to receiving waters. This method is expected to increase reliability of annual water quality modeling results by providing realistic input data.