This study estimated response of water quality and pollutant behavior according to the discharge and reuse of treated wastewater by three-dimensional eco-hydrodynamic model, and suggest plan that water quality management and environmental restoration in the coastal area including urban stream of Yeosu, Korea. Dispersions of low-saline water and COD by treated wastewater loads (design facility capacity, about 110,000 m3/d) were very limited in near of effluent site. Nutrients, however, increase compared to the other water quality factors, especially total nitrogen was very sensitive to input loads. When reuse some of treated wastewater to Yeondeung stream, nitrogen was big influence on estuarine water quality. Although current characteristics of treated wastewater such as discharge and water quality were negligible to the change of marine environment, effluent concentration of COD, TN and TP, especially 40% of TN, are reduced within the allowable pollutant loads for satisfy environmental capacity and recommended water quality criteria. Also, controls of input point/non-point sources to Yeondeung stream and base concentration of pollutants in coastal sea itself are very necessary.

Water pollution in enclosed water bodies such as lake and river has become a serious problem over the world. Domestic wastewater is responsible for more than 60 % pollution load in public water area in Korea. Effluent of the treated domestic wastewater at low removal level is abundantly fed rivers and lakes and thus be an serious cause of lake pollution. Therefore, effective implement of domestic wastewater treatment in basin of lake and river must be prepared. The septic tank is one of the effective domestic wastewater treatment equipment and used in individual treatment for a unit of household. The purpose of septic tank as biological treatment system is simultaneously to remove BOD, T-N, T-P and reduce turbidity from influent. Accordingly, the appropriate control of functional microorganisms is important subject for the establishment of stability and economy of the biological treatment method. Especially, microanimals as a high-ranked microorganisms of food-chain are important, because microanimals control the other microorganisms especially various bacteria and effect on function of treatment. Therefore, it is necessary that functional predator like rotifers are attached in wastewater treatment process. In this study, the methods for attachment high density the rotifer to and improvement of transparency in the effluence by a dense rotifer was examined using laboratory scale biological treatment reactor simulated septic tank and real one.

금번 연구에서는 낙동강 유역내 주요하천을 대상으로 자연도 평가와 수질을 분석하였다. 하천 자연도의 종합평가 결과는 의 1등급과 4등급으로 평가되었으며, 부문별 평가 결과는 하천형태의 평가지수가 로 2등급에서 4등급으로, 하천환경의 평가지수는 의 1등급에서 4등급으로 평가되었다. 수질 평가 결과는 수소이온농도는 이었으며, 생물화학적 산소요구량은 , 용존산소량 , 부유물질은 이었다. 하천 자연도 평가 지표의 독립성과 유사성을 판단하기 위하여 하천 자연도

본 논문에서는 두 가지 대표적인 하천수질모형을 비교분석하였다. 정상상태 모형으로는 QUAL2E, 비정상상태 모형으로는 CE-QUAL-RIV1을 선택하여 동일한 반응계수 및 경계조건 하에서 두 모형의 계산결과를 서로 비교해 보았다. 각 모형에 대하여 수질변동을 계산하기 위해 적용된 방정식을 서로 비교하였으며, 두 가지 수질모형을 이용하여 대청댐 이하 금강본류의 수질을 모의하였다. 두 모형은 기본 알고리듬이 매우 유사하므로, 모형구축에 필요한 입력자료도 매

하천을 따라 분포된 비점 오염원을 하천 수질모형의 매개변수들과 동시에 추정하는 체계적인 방법을 제안하였다. 수립된 방법을 QUAL2E 모형과 함께 충주댐 하류의 남한강 구간에 적용하여 모형의 반응계수와 비점 오염 부하량에 대한 최적 추정을 수행하였다. 민감도 분석 결과로부터 선정된 반응계수들에 대한 초기 추정 결과에 따르면 하천 시스템에 대한 질량수지가 만족되기 위해서는 질소와 인의 비점 오염 부하량의 입력이 필요한 것으로 나타났다. 이에 따라 총질소와

갈수기 동안 우리나라 하천의 자정능력은 상류 댐으로부터 공급되는 하천유지유량에 큰 영향을 받으므로, 하천과 저수지시스템의 운영은 수량공급측면뿐만 아니라 하천의 수질과 생태계를 동시에 고려해야 한다. 본 연구에서는 수질사고와 악화에 취약한 갈수기 동안 다양한 댐 방류 대안이 하류 수질에 미치는 영향을 평가하기 위한 비정상상태 하천수질모형인 KORIV1-WIN을 개발하고 금강수계에 위치한 대청댐 하류구간을 대상으로 2002년 9월과 10월에 실측한 유량과

본 연구에서는 최근 환경재료로서 관심이 모아지고 있는 다공성 콘크리트를 하천구조물(보 및 하상재료)에 적용함으로써 수질을 개선하고자 수행하였다. 먼저, 물리ㆍ화학적 특징을 평가해 본 결과, 공극률 10% 및 30%의 다공성 콘크리트의 압축강도는 일반 콘크리트의 최저 압축강도(180 kgf/)를 상회하여 하천구조물에 적용 가능하였고, 알칼리 용출에 의한 부착 미생물에의 영향도 거의 없을 것으로 판단되었다. 또한, 일반 콘크리트와 다공성 콘크리트로 하천구조

It is the purpose of this study to investigate the change of stream water quality in upper stream of Dongjin river, and to give the basic information for the conservation of water quality. Water samples were taken periodically at 9 sampling sites during 8 months from March to October in 2002. The results of this study were as follows : 1. The water temperature and pH of stream water were ranged 9.0~29.4℃, 6.48~9.33, respectively. The COD values of stream water was ranged from 0.60 to 19.06. The contents of T-N and T-P mainly affected by the livestock wastes, and agricultural activity were 1.88~6.74 mg/L, ND(not deleted)~0.50 mg/L, respectively. 2. The SS, DO and BOD values of stream water were ranged 0.4mg/L~274.0mg/L, 0.5~6.0 mg/L, and 7.3~13.7 mg/L respectively. 3. The cation is one of the important components in analysis of stream water quality. The contents of analysis, Ca++, Mg++, Na+ and K+ were ranged 1.96~11.08 mg/L, 1.21~6.16 mg/L, 3.38~18.44 mg/L, 1.12~7.96 mg/L, respectively. SAR was ranged 0.31~1.63 below 2.0. The contents of cation showed in the order Na++>Ca++>K+>Mg+. 4. The contents of heavy metal Zn, Cu, and Pb were ND~0.071 mg/L, ND~0.012 mg/L, and ND~0.043 mg/L, respectively. Cd was not detected in all samples. 5. As a result of these researches showed water quality in upper stream watershed of Dongjin river more affected by livestock wastes and living sewage than agricultural activity.

도시하천 하류부에서의 하상퇴적토 준설에 따른 수직개선효과를 검토하기 위해 유한차분법을 사용하여 목표년도 하수의 차집율에 따라 목표수질 달성에 대한 기여정도를 분석하였다. 도시를 관류하고 있는 11.2km의 하천구간내에 21개 지점을 선정하여 시추를 실시하였으며, 용출시험을 통한 하상퇴적토의 오염정도을 조사하였다. 하상퇴적토 준석에 따른 주요지점별 COD 변화를 갈수량, 저수량 및 평수량에 대해서 검토하였고, 그 결과 오염된 하상퇴적토의 준설이 수질개선에

This study aims at the development of the model for a forecasting of water quality in river basins using artificial neural network technique. Water quality by Artificial Neural Network Model forecasted and compared with observed values at the Sangju 1 and Dalsung stations in Nakdong river basin. For it, a multi-layer neural network was constructed to forecast river water quality. The neural network learns continuous-valued input and output data. Input data was selected as BOD, DO, discharge and precipitation. As a result, it showed that method Ⅲ of three methods was suitable more than other methods by statistical test(ME, MSE, Bias and VER). Therefore, it showed that Artificial Neural Network Model was suitable for forecasting river water quality.

The studies on physico-chemical factors and phytoplankton at the 3 rivers in the Taejon city were conducted from November 1997 to May 1998. The Results were as follows; In the water quality, the down streams were generally worse than the upper streams. Water temperature was varied from 2.4℃ to 23.0℃; DO from 1.80㎎/ℓ to 17.6㎎/ℓ ; pH from 4.7 to 10.4 ; BOD from 0.78㎎/ℓ to 8.80㎎/ℓ; COD from 0.32㎎/ℓ to 8.26㎎/ℓ ; SS from 2.0㎎/ℓ to 43.0㎎/ℓ ; total phosphate was from 0.001㎎/ℓ to 0.709㎎/ℓ ; total nitrogen 0.01㎎/ℓto 11.69㎎/ℓ . In phytoplankton species, they were identified as total 191 taxa composed of 8 classes, 18 orders, 35 families, 74 genera, 152 species, 35 varieties and 4 forms. The dominant species were Synedra ulna in Taejon-chon, Diatoma vulgare in Yudong-chon, Oscillatoria princeps, Scenedesmus gadricauda, Synedra ulna, and Diatom vulgare in Gap-chon. Standing crops of phytoplankton were from 2,076 cells/㎖ to 97,356 cells/㎖.

농촌 소하천의 수리학적 및 수질특성을 반영한 모형을 개발하였다. 모형구조 설계시 제어체적 기법을 활용하여 하천 형상, 수질 및 유량의 변화가 심한 농촌 유역의 소하천에 대한 수질의 모의하였다. 개발한 모형에 난수발생기법을 도입하여 최적 반응계수와 모형구조를 추정하였다. 또한 모형 보정기준의 일반화를 위해 동의지표와 효율계수를 도입하여 매개변수추정의 신뢰성 향상을 도모했다. 모형의 적용성을 검증하기 위해 경남 김해시 한림면 용덕천에서 수질을 채취하여 분석

In order to manage the water quality from the flowing streams in Cheju Island, the characteristics of water quality was investigated from August, 1996 to May, 1997 and the pollutant loadings for future were estimated from the watershed at each stream. Comparing the mean concentrations of each water quality with the criterion of water quality in river, it was under I class except for Changgo Stream, for DO, under I class at the whole station for SS and under Ⅱ class for BOD. As the pollutant loadings at each stream in 2020 is compared with those in 1996, the estimated results are as follows : 1) for BOD, 59% at Donghong Stream, 24% at Yeonoe Stream, 44% at Ohngpo Stream and 57% at Changgo Stream. 2) for T-N, 91% at Donghong Stream, 76% at Yeonoe Stream, 63% at Ohngpo Stream and 89% at Changgo Stream. 3) for T-P, 69% at Donghong Stream, 42% at Yeonoe Stream, 45% at Ohngpo Stream and 73% at Changgo Stream The point source loadings discharged through combined sewer could be treated at sewage treatment plant. However, the expected slow decreasing rate of BOD, T-N, and T-P loadings is due to the part of untreated nonpoint source loadings. Nonpoint source loading overflow typically occurs when the flow of stormwater combined with sewage exceeds the capacity of the interceptor sewers. Since most of the sewers used in Cheju Island are the combined sewers, the combined overflow sewage is bypassed into the receiving water area after a rainstorm. Therefore, a means to control nonpoint source loadings should be considered for the river and marine water quality management.

This study was carried out to develop the stream water quality model for the intaking station of Kongju waterworks in the Keum River system. The monthly water quality(total nitrogen and total phosphorus) with periodicity and trend were forecasted by multiplicative ARIMA models and then the applicability of the models was tested based on 7 years of the historical monthly water quality data at Kongju intaking site. The parameter estimation was made with the monthly observed data. The last one year data was used to compare the forecasted water quality by ARIMA model with the observed one. The models are ARIMA(2,0,0)×(0,1,1)_12 for total nitrogen, ARIMA(0,1,1)×(0,1,1)_12 for total phosphorus. The forecasting results showed a good agreement with the observed data. It is implying the applicability of multiplicative ARIMA model for forecasting monthly water quality at the Kongju site.

The purpose of this study was to investigate the pollutions of water qualities in 30 water samples from Nakdong River, Western Nakdong River, and Suyoung Stream. COD, BOD, T-N and negative ions(F-, Cl- NO3-, SO42-) of water samples were analyzed and the correlationships between water qualities were examined. The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were the highest in the water sample of Suyoung Stream among the three streams and those of F-(0.25ppm), Cl-(27.70ppm), and SO2-(37.66ppm) in Western Nakdong River, that of NO_3,(10.81ppm) in Nakdong River. The water quality of Suyoung Stream was the worst among the three streams in Pusan area. The correlationships between water qualities were as follows ; BOD and COD showed very high correlationship(correlation coefficient, r=0.97), SO42- and NO3- did high one(0.75), and NO3- and COD, BOD did relatively high ones(0.56 and 0.48, respectively).

The purpose of this study is to analyze structural and ecological characteristics of streams in rural village. The methods used in this study were measuring the section and surveying the vegetation of the stream at three points(upstream, inner village, downstream ) of 10 rural villages. The major findings of this study can be summarized as follows : 1) The average width of streams is 9 m, and the height of banks 3.1 m. the downstreams are the widest(average 10 m), and the inner-villages are the narrowest (average 8 m), and the slopes of basin are 7.33 %, 2.67 %, 1.39 % at upstream, inner-village, downstream respectively. 2) The downstreams are more contaminated than upstreams due to the sewage from the residents, especially livestock wastewater. 3) The dominant species in the streams are Persicaria thunbergii H. Gross (average Cover 17.76 %) and cumulus japonicas Sieb et. Zucc (average Cover 7.75 % ). 4) The average area covered by vegetation is 53.31 % the downstreams are covered 65.7 %, but inner-village area covered by vegetation is 46.6 %. 5) The problem found in this study are severe water contamination, poor accessibility to stream and poor vegetation of inner-village area, etc.