• 한국물환경학회지
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• 제29권5호
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• pp.630-640
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• 2013

It is one of the most critical steps identifying impaired waterbodies exactly in the selection of target water quality indicators for the management of Total Maximum Daily Loads (TMDLs). Excess ratio and excess level were applied and analyzed by the stream zone basis in order to evaluate water impairment for Nakdong, Geum, Youngsan and Seomjin rivers. Each river basin was divided into stream zones in the light of its watershed and waterbody characteristics. Selected water quality parameters discussed in this study were pH, DO, BOD, COD, SS, T-P, T-Coli and F-Coli. The excess ratios of the water quality parameters were used to discriminate water bodies that did not meet water quality standards. The excess levels were used to classify the degradation of water quality. The excess ratios and the excess levels to the water quality criteria of the medium influence areas were used for each stream zone. The results indicate that the excess ratios and the excess levels are varied on the stream zone in each river basin. Three parameters, pH, DO and SS, met water quality standards in all stream zones. The other five parameters indicated very high excess ratios in most waterbodies, and especially T-P and T-Coli revealed to be very high excess levels in some waterbodies. These parameters could be considered as major target indicators for the management of TMDLs.

• 한국물환경학회지
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• 제30권2호
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• pp.128-137
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• 2014

The land use of the unit watersheds should be maintained appropriately in order to keep the load allotment stable for the management of Total Maximum Daily Loads (TMDLs). This study classified the land area in four types and analyzed the use of each land type and its changing pattern by calculating the occupation and conversion ratios for the unit watersheds in three river basins. The forest land showed the greatest occupation ratio with 63.0%, followed by the farm land with 23%, the other area with 8.0% and the site area with 6.0% in 2003. The occupation ratio of the site and the other area increased by 0.4% and 0.2% respectively, and that of the farm and the forest land decreased by 0.4% and 0.2% respectively in 2007. The conversion ratio for the site area ranged from 1.65% to 1.97%, for the farm land from -0.47% to -0.33%, for the forest land from -0.10% to -0.04% and for the other area from 0.17% to 1.97%. It can be inferred that the decrease in the farm and the forest land contributed to the increase in the site area and that the increase in the other area was mainly made by the decrease in the forest land. It could be more effective to take into account the changes in the site area and in the forest land in the process of developing the TMDL plans.

• 한국수자원학회논문집
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• 제36권1호
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• pp.117-128
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• 2003

본 연구에서는 소유역에서의 오염총량을 추정하기 위하여 위성영상 카테고리분류 인공신경망 모형과 지리정보시스템 기반의 오염총량모의시스템(Total maximum daily Loads simulation System, TOLOS)을 개발하였으며, 발안유역의 HP#6 소유역을 시험유역으로 선정하여 유역 수문·수질 모니터링을 수행하였고, 시험유역의 도형 자료를 구축하여 TOLOS의 적용성을 평가하였다. TOLOS의 오염총량추정 모듈인 SWAT 모형은 논에서의 지표배수량을 고려하여 구성하였다. TOLOS을 이용하여 일별 측정 자료인 유출량, 유사량, 그리고 영양물질에 대하여 SWAT 모형의 보정과 검정을 실시하였으며, 그 결과 적용 가능성이 있는 것으로 나타났다.

• Ecology and Resilient Infrastructure
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• 제9권3호
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• pp.174-182
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• 2022

수질오염총량관리제도 추진 절차 중 시행계획 이행평가 사업의 대가는 기존 환경부 용역비 지원기준에 따라 산정하고 있다. 그러나 용역비 지원기준은 기본금에 해당 유역면적과 인구 규모에 따른 가산금을 합산하여 대가를 산정하도록 구성되어 있어 사업의 특성을 상세히 반영한 대가를 산정하기 어려운 구조이다. 따라서 본 연구에서는 이행평가의 상세 업무별 영향을 미치는 요인으로 단위유역별 면적, 인구, 축산 두수, 폐수배출업소 등을 반영한 표준품셈을 적용하여 대가산정 방안을 제안하고 그 적정성을 검증하였다.

• 한국물환경학회지
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• 제25권1호
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• pp.125-135
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• 2009

Reliable long-term flows by SWAT-K model were applied to the relationship between stream flow and pollutant load derived from 8-day measured data of Ministry of Environment (MOE) in order to obtain continuous loadograph and evaluate accuracy in water quality modeling for the Chungju dam watershed. The measured flow were compared with flow duration curve from the model, and it showed that measured values corresponded to the almost full range of stream flow conditions except at Odae A. And there was significant relationship ($R^2=0.60{\sim}0.97$) between measured flow and water quality load at all unit-watersheds. Applying this relationship to simulated flows, continuous loadograph was obtained and compared with modeled pollutant loads. Although there were some differences during some dry and flood seasons, those were not significant and overall trend showed a good agreement. From the results, we would be able to derive a continuous loadograph based on measured data at total maximum daily loads (TMDLs) unit-watersheds on a national scale, in which stream flow and water quality have been measured at 8-day intervals since 2004, and this could be helpful to utilize distributed water quality models with difficulty in calibrating and validating parameters from lack of measured data at present.

• 한국물환경학회지
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• 제24권4호
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• pp.452-457
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• 2008

Nonpoint source (NPS) pollution is caused by rainfall moving over and through the ground. As the runoff moves, it picks up and carries away various pollutants from NPS. The discharge pattern of NPS pollutant loads is affected by the distribution of the rainfall during the year. This study analysed relationship between the rainfall event and the stream flow rate, and estimated the rainfall discharge ratio on the specific design flow which can be used as nonpoint discharge coefficient for the estimation of NPS pollution load. It is considered that nonpoint discharge coefficient can be effectively used for the calculation of NPS pollution load at the time of water quality modelling for the management of Total maximum daily load (TMDL).

• 한국물환경학회지
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• 제25권6호
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• pp.972-978
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• 2009

This study modifies the present total maximum daily load (TMDL) system of Ministry of Environment and applies to the Anyangcheon watershed. Hydrologic Simulation Program-FORTRAN (HSPF) model is used to simulate both runoff and non-point source pollution, simultaneously, instead of QUAL2E. The drought flow (355th daily flow) is proposed for the target water quantity since it is easier to satisfy low flow (275th daily flow) for the target water quality than drought flow. The increase of discharge is more than the increase of pollutant load except for the period under low flow. The measured unit loads for non-point source are used to consider the regional runoff characteristics. The measured water quantity and quality data are used since the ministry of environment supports only water quality. This analysis results show some reasons for the improvement of the present TMDL system of Korea.

• 한국물환경학회지
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• 제26권4호
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• pp.648-653
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• 2010

Discharged pollution load for the management of Total Maximum Daily Loads (TMDLs) is calculated on the basis of rainfall data for reference year. Rainfall has an influence on discharged pollution load in unit watershed with combined sewer system. This study reviewed the status of discharged pollution load and rainfall conditions. We also investigated rainfall effects on discharged pollution load by analyzing change of the load in accordance with increase of rainfall. The change ratio of discharged pollution load was 18.6% while inflow load only 5.8% for 5 years from 2004 to 2008 in Daejeon district. The greatest rainfall and rain days were over 2 times than the least during the period. This change in rainfall could have great effect on discharged pollution load. The analysis showed that discharged pollution load increased 2.1 times in case rainfall increased 2 times and 1.2 times in case rain days increased 2 times. Rainfall effects, therefore, should be considered to make resonable evaluation of discharged pollution load in the assessment of annual performances.

• 한국물환경학회지
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• 제24권6호
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• pp.676-681
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• 2008

The evaluation of the effluent water quality of sewage treatment plant is one of the most important factor in calculating total maximum daily loads (TMDLs). Current method to calculate 95% upper limit of effluent water quality of sewage treatment plant assuming normal distribution of data needs to be implemented in case of non-normal distribution. We have investigated the applicability of percentile ranking method as a non-parametric statistical analysis in case of non-normal distribution of data.

• 환경영향평가
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• 제18권1호
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• pp.1-9
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• 2009

Even though the center of Cheongju city needs redevelopment because of a doughnut phenomenon, it has to be permitted within the environmental carrying capacity like a target water quality proposed on the Total maximum daily loads(TMDL) of Musim and Miho river watersheds. The aim of in this study is to identify the limit of redeveloping Cheongju downtown after analyzing its environmental carrying capacity using QUAL2E model. As a result of modeling various scenarios, the water quality of Musin river was shown that $BOD_5$ is 2.3mg/L which is the target water quality in the double of existing development plan of the Cheongju downtown. The water quality of Miho river was $BOD_5$ 3.97mg/L which is less than the target water quality of Miho B watershed in the same condition. Therefore, this means that the limit of redevelopment within the environmental carrying capacity of cheongju downtown was estimated to be the double of existing development plan.