• Journal of Korea Water Resources Association
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• v.45 no.9
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• pp.929-941
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• 2012

In recent years, interest in river environment such as riparian landscape, water quality and ecological conservation has been growing with increasing recreation on agricultural river watershed. That caused the increase of necessity of water resources development, one of solutions for the diversification of agricultural water demand and shortages. In this respects, heightening irrigation dam, as a part of the 4-major river restoration project, is necessary to secure not only additional agricultural water but also instream flow for water quality improvement. However, operation plan of irrigation dam still not be clear. In this study, additional storage which secured through heightening irrigation dam was estimated using SWAT model. And instream flow effects on water quality of downstream were evaluated. The findings show that the additional water supply will contribute positively to water quantity and quality of downstream. The results show a 2~10% water quality improvement effect on nutrients, as well as an 1~8% water quantity increasing effect. In particular, additional storage can be effectively supplied from February to April by the reservoir operation. However, maintaining better water quality in irrigation reservoirs is important because the water quality of irrigation reservoirs can be negatively impacts the water quality in downstream of reservoirs.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.538-547
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• 2017

Korea's water management system is typically a multi-ministerial system, so its efficiency is declining. In order to propose current state and improvement plan of the water management in Korea, this study discussed the improvement of central and local water management. The water management problems are lack of water policy coordination system, conflicts between ministries due to function of water quantity, water quality and agricultural water, redundant investment and inefficiency, insufficient recognition of water autonomy, concentrated central management and deepening regional disparities, lack of financial resources, etc. Hence, improvement to solve the problem includes strengthening the coordination of water management functions between ministries, transferring water management functions of central ministries and strengthening local capacity, and desirable role allocation of central and local governments. In addition, improvement at the local include efforts to change awareness of the water detailed and get water autonomy, integrate management of the watershed, strengthen the local community, secure financial resources, etc.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.547-554
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• 2011

In small-scale water systems, the measurement of quality of raw water in running water is generally implemented when the quality of water is stable and frequency of measurement is low. However, units such as water temperature and pH, which are easily monitored, are frequently measured. In establishing an improvement plan for a water treatment system, the range of concentration of the target material present in the raw water of the running water provides relevant information. If the concentration of target material can be specified by the quality of water of data items that are measured daily, inverse estimation of the range of concentration is possible as well. In this paper, we took note of manganese in the raw water from Ogasawara-mura, Tokyo, and estimated the manganese concentration in the raw water of the running water for the past five years. Based on the results obtained, we have proposed a manganese removal system, considering the current situation and geographical conditions of Ogasawara-mura.

• Journal of Korean Society on Water Environment
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• v.30 no.2
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• pp.148-158
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• 2014

In order to assess the effect of TMDLs management and improve that in the future, it is necessary to analyze long-term changes in water quality during management period. Therefore, long term trend analysis of BOD was performed on thirty monitoring stations in Geum River TMDL unit watersheds. Nonparametric trend analysis method was used for analysis as the water quality data are generally not in normal distribution. The monthly median values of BOD during 2004~2010 were analyzed by Seasonal Mann-Kendall test and LOWESS(LOcally WEighted Scatter plot Smoother). And the effect of Total Maximum Daily Loads(TMDLs) management on water quality changes at each unit watershed was analyzed with the result of trend analysis. The Seasonal Mann-Kendall test results showed that BOD concentrations had the downward trend at 10 unit watersheds, upward trend at 4 unit watersheds and no significant trend at 16 unit watersheds. And the LOWESS analysis showed that BOD concentration began to decrease after mid-2009 at almost all of unit watersheds having no trend in implementation plan watershed. It was estimated that TMDLs improved water quality in Geum River water system and the improvement of water quality was made mainly in implementation plan unit watershed and tributaries.

• Proceedings of the Zoological Society Korea Conference
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• 1998.10b
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• pp.200.1-200
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• 1998

No Abstract, See Full Text

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.45-45
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• 2004

• Journal of Korean Society of Environmental Engineers
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• v.38 no.3
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• pp.117-127
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• 2016

In this study, analyzed scenarios of the environmental instream flow for water quality improvement in Saemangeum watershed. In order to get an environmental instream flow, Methodology is selected for Retention-Basin, reservoir expansion, new dam construction, Modification of water intake and drainage system, Rearrangement of plan for system which Yongdam and Seomjin river dam have been used water supply. The study composed of diverse scenario of Environmental instream flow increasement and analyzed the effect of improving the water quality by the QUAL2K model and calculation of runoff for saemangeum watershed by SWAT model. The following water quality indicators have been simulated in irrigation and non-irrigation period for BOD and T-P. When scenarios applied to water quality model, Improvement rate in the water quality for Total Maximum Daily loads of Mankyung B unit watershed during irrigation and non-irrigation period is BOD (28.70%), T-P (17.09%) and BOD (28.51%), T-P (28.68%) respectively. Dongjin A unit watershed during irrigation and non-irrigation period is BOD (14.39%), T-P (14.59%) and BOD (15.54%), T-P (19.46%) similary. Simulation results is to quantify the constribution of the improvement in the water quality. In particular, It was demonstrative that improving effect for water quality was evaluated to be great in non-irrigation period.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.1
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• pp.73-82
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• 2000

Large quantitive of polllutants are washed into reservoirs during storm events. These polllutants contribute to eutrophication, such as algal blooms and fish kills. This study was conducted for the purpose of assessing the pollutant removal possibilities of sedimentation pool formed by deep dredging of a reservoir inlet. Water quality data were collected in the Masan reservoir, whose inlet has been dredged deep like sedimentation pool. The average concentration of chemical oxygen demand(COD) , toatal nitrogen(T-N) and total phosphrous(T-P) in the deep dredged area were 8.7 ~20.5mg/ι (T-N), 0.17~0.84mg/ι(T-P), which were 4.9%(COD), 29.0%(T-N) and 44.8%(T-P) higher than those of middle part of the reservior. The texture of sediment in the dredged area was silty loam, while that of the middle part was sandy clay loam. Organic matter contents, T-N and T-P of the bottom soil in the dredge area showed higher values than the middle part of the reservoirs. From these results, it was considered thedeep dredged area in the inlet of reservoir might play a key role to settle pollutant particulate. Based on the result of water quality analysis, deep dredging of the reservoir inlet could be assessed to reduce T-N and T-P of the reservoir about 6.5% , 8.3%, respectively. However, the effect of the sedimentation pool would be raised if the settled particles were taken into account in assessing water quality improvement for the reservoir. Accordingly, dredging of a reservoir inlet to make a shape of sedimentation pool is recommended for water quality improvement of reservoir in the stage of dredging plan.

• Journal of Korean Society on Water Environment
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• v.37 no.1
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• pp.32-46
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• 2021

South Korea has been divided into quantities and water quality, and due to a revision of the Government Organization law in June 2018, the controversial water management system was integrated into the Ministry of Environment. The total Maximum Daily Loads System has been called the flower of water quality control, and since 2004, all three major river systems which have been introduced into the Han River system, despite its various difficult environments, and subsequently leading to all of the four major rivers undergoing obligatory implementation since 2013. Currently, the target TMDL (Han River Phase 1 and Other Water Systems Phase 3) for the 2020 stage has been implemented. The domestic TMDL established a basic plan for calculating the load which complies with the unit watershed's target water quality, as well as an implementation plan for annual load management, both which have been institutionalized in order to evaluate load compliance on a repeated annual basis. Local governments ask external organizations to conduct investigations every year in order to assess the transition, which thereby requires tens of millions of won every year. Therefore, an assessment and management model that can be easily operated at the TMDL personnel level is required. In this study, when the Han river Water System TMDL was implemented in earnest, we confirmed the the water quality improvement effect when TMDL was introduced to major inflow tributaries (TancheonA, JungnangA, AnyangA) under the Seoul City's jurisdiction through the use of the total amount control unit basin evaluation technique. By presenting customized management measures, we propose the guidelines that are necessary for determining more effective water environmental policies.

• Journal of Korean Society on Water Environment
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• v.39 no.5
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• pp.377-389
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• 2023

Chungcheongnam-do has been measuring the flow rate and water quality of streams in the province once a month since 2011 in order to water environment policies. Based on the results, after evaluating the coefficient of variation and the tendency of the water quality trend by using the Mann-Kendall test and Sen's Slope for each stream, the streams subject to priority introduction of Total Pollution Load Management at Tributaries were selected through the Stream Grouping Method. The water quality trend analysis results for 125 streams using the Mann-Kendall test and Sen's Slope were evaluated as streams showing a tendency of deteriorating water quality Biochemical oxygen demand (BOD): 13 streams, Total Phosphorus (T-P): 16 streams). Streams with deteriorating water quality were classified into A-D groups using the Stream Grouping Method. Group A, which has a high flow rate and high water quality, is a stream that requires priority management, and was selected as a stream for introduction of Total Pollution Load Management at Tributaries. There are 7 streams that need to be introduced into the BOD category, and there are 7 streams that need to be introduced into the T-P category. In this study, based on flow and water quality monitoring data accumulated over a long period of time (2011-2022), statistical techniques are used to select watersheds in which water quality is deteriorating. Accordingly, it is expected that it will be useful in establishing a water quality improvement plan in the future.