• 상하수도학회지
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• 제23권5호
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• pp.637-645
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• 2009

To understand the financial situation of waterworks, the revenue and operation cost from 1996 have been analyzed. The budget of waterworks was 3,775 billion won in 1996 and grew up to 5,774 billion won in 2007. The budget has grown about 1.53 times during 11 years. Based on 2007, total cost for supplying water, rehabilitating old facilities and returning debt and its interest was 4146 billion won. The cost was recovered by 2,825 billion won of water revenue, 827 billion won of various fees revenue, 571 billion won of financial grant and 89 billion won of loan. Until 2007, the 15.3% of operation cost for waterworks was covered by government grant and loan. The renovation cost for old non-efficient facilities was 1,356 billion won in 1996 and was 1,486 billion won in 2007. The renovation cost was not increased remarkably during 10 years. Since the total operation cost was increased about 1.5 times, the percentage for renovating old facilities was decreased from 36% to 25.7%. This trend need to be alerted because the renovation has been slow down when the facilities for water supply need more rehabilitation.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.260-266
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• 2009

본 연구는 지방상수도 배급수 관망의 유수율을 향상시키기 위하여 수량관리를 위한 블록시스템 구축을 통한 구역화 계량, 누수의 정량화를 위한 야간최소유량 측정을 통한 누수평가지표 및 국제 누수지수ILI(Infrastructure Leakage Index)의 도입, 압력제어를 통한 누수저감 효과분석, 장기적인 계획수립을 위하여 노후수도관의 잔존수명 예측 등 누수를 평가 관리할 수 있는 기술을 개발, 제안하였다. N시 야간최소유량 측정을 통하여 주거지역과 상업지역에서 정량적인 누수평가지표로 관길이당, 급수전당의 허용기준누수량을 산정하였다. 이는 관망정비가 완료된 주거, 상업지역을 각각 대상으로 UK water industry에서 제안한 방법을 이용하여 실측을 통한 야간최소유량을 분석함으로써 유수율을 대신할 수 있는 허용누수량 산정식을 개발하였다. 압력제어를 통한 누수저감효과는 감압변의 설치를 통하여 수행되는데, 사천시 우티 배수구역을 대상으로 압력관리 구역을 4개로 분할하고 감압밸브 3개소, 가압펌프 1개소를 설치하여 압력을 조절한 결과 약 $466\;m^3/day$의 누수를 저감시킬 수 있을 것으로 나타나 압력관리를 통하여 연간 113백만의 비용절감효과가 기대되었다. 노후 상수관로의 부식속도 및 잔존수명 예측 연구에서는 매설년도, 토양 또는 수질특성에 따른 관체의 부식속도를 평가함으로써 잔존두께를 예측할 수 있는 모델을 개발하였으며 또한 부식으로 인한 공식특성에 따른 잔존강도 등을 평가할 수 있는 비선형회귀 모형을 개발, 수도관의 잔존수명예측에 활용하여 장단기 노후관 개대체 계획수립에 활용할 수 있도록 제안하였다. 본 연구의 결과들은 지방상수도의 유수율 제고 및 관망정비사업에 적극적으로 활용할 수 있는 누수평가 및 관리기법을 제안할 수 있을 것으로 기대된다.

• 상하수도학회지
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• 제35권3호
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• pp.237-246
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• 2021

The ILI, developed by the IWA (International Water Association), has been used in many countries as an indicator of water leakage. In Korea, the revenue water has been used as a performance indicator for waterworks although there is an opinion to replace it with the ILI. Hence, it has been necessary to investigate whether the ILI can replace the revenue water in Korea. The four main operating indicators (i.e., water service population, profit-loss ratio, fiscal self-reliance, and aged pipe rate) of 162 Korean waterworks were compared with the ILI with the linear regression method. Local water authorities with more than 1 million water service population, with more than 60% profit-loss ratio, more than 40% and less than 60% fiscal self-reliance, and more than 20% aged pipe rate showed meaningful correlation between the four parameters and the ILI. In the remaining cases, their correlations were little or weak. This means that using the ILI may not be an efficient method to represent the performance of the water supply system in Korea because of the lack of UARL (Unavoidable Annual Real Losses) data accuracy. To use the ILI in Korea, it will be required to carry out an additional research to accumulate reliable CARL (Current Annual Real Losses) and UARL data in the future.

• Water Engineering Research
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• 제2권2호
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• pp.103-112
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• 2001

Issues and problems in formulating South Korea's water resources policy are discussed in terms of water quantity and quality. South Korean needs both water conservation and water supply capability for the growing population and economic activities. The government has attempted to build more large-scale dams to store and supply water for residential, farming and industrial uses, but the environmentalists who emphasize conservation and environmental protection oppose the government. The environmentalists are popular among the general public. Water quality has been deteriorating from point- ad non-point sources. urban and farm runoffs are serious pollutants. All want by preserve water quality. There is no dispute on this matter between the government and the environmentalists. Money is hard to come by to preserve water quality. Economic and financial crises and no self-sufficient local governments' revenue structure are pessimistic. Basic survey on water resources, hydrology and hydraulic is badly needed for the future water resources planning.

• 상하수도학회지
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• 제31권2호
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• pp.149-159
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• 2017

It is considered necessary to renewal a considerable number of water supply facilities in Korea because they began to be intensively buried in the period of rapid economic growth. Accordingly, local water providers are required to take measures against this situation, but they have currently been caught in a vicious circle of the lack of budget spent in renewing water supply facilities because county-based small-scale local water supply cannot afford to cover annual expenditures with their revenues from water rates. Therefore, this study developed an optimal renewal planning model capable of achieving a balance of financial revenue and expenditure in local water supply using nonlinear programming and furthermore of minimizing the total cost incurred during the analysis. To this end, this study selected the water supply area located in County Y as a research area to build the financial revenue and expenditure and used Solver function provided by Microsoft Excel to use nonlinear programming. As a result, this study developed an optimal renewal planning model minimizing incurred costs in consideration of 6 items in the financial revenue and expenditure. The optimal renewal plan was modeled according to the available annual budget. As a result, this study proposed SICD, a scenario to minimize total costs from the perspective of water suppliers, and SITS, a scenario to minimize the increase in water rates from the perspective of consumers. It can be said that the method proposed in this study is the core of the optimal financial and renewal plans as a final stage of asset management for water supply facilities. Therefore, it is considered possible for local water providers to use the method proposed in this study according to circumstances for the asset management of water supply facilities.

• 상하수도학회지
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• 제28권5호
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• pp.509-516
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• 2014

This study describes a reasonable planning method for water meter replacement which can minimize the metering under-registration for an increasement of revenue water. The increment analysis of real water usage was used to establish a replacement plan. The meter replacement database collected from K City was used as the basis of this analysis. The database included 964 connections of domestic and non-domestic consumers that had their meter replaced by aging at 2011. The result showed that the corelation between unregistered water volume and water meter age was lower than commonly expected where the current criteria of replacement is only water meter age(8 years) excluding the meters older than 13 years. And in the analysis result of water usage for 8 years, the total amount and increment of water usage had a significant effect on unregistered water volume. However the relation was different tendency as a total volume and slope of increment. In case of total water volume was larger than 10,000, larger than 7,000 and increment of 0.0 ~ -0.3, larger than 6,000 and increment more than -0.3 were analysed to need a replacement because of metering under-registration.

• 한국습지학회지
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• 제22권3호
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• pp.200-216
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• 2020

Many studies conducted in Kenya regarding water resource governance have focused on the mandate of Water Resource Users Associations (WRUAs) with less attention being accorded to their effectiveness in conservation of wetlands. This study assessed the effectiveness of WRUA committees, and challenges faced in conservation of Rwamuthambi Sub-catchment. The study employed exploratory descriptive research design. Data was collected through questionnaires, semi-structured interviews, observations and review of secondary data. Chi square and descriptive statistics was used to analyze the data. The survey results revealed that only 15% of WRUA committee understood water resources management while 35% were aware of relevant legislations. Factors of wetland degradation showed significant association with existence of WRUA (χ2 (4, N=180) = 20.46, p< .01) where (χ2- chi square (degrees of freedom, N = sample size) = chi-square statistic value, p = p value), although WRUA contributions were perceived differently per agro-ecological zone (χ2 (8, N=147) = 15.51, p>.05). Challenges unearthed were inadequate financial and human resources, lack of understanding, ineffective collaborative governance, poor support from county government and private ownership of riparian land reserve. There is need for WRUAs to embrace collaborative governance for effective conservation of wetlands. Integration of sub catchment management plan with county land use plans and policy review is also required.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.160-160
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• 2019

Water is a limited source that needs to be properly managed and distributed to the ever-growing population of the world. Rapid urbanization and development have increased the overall water demand of the world drastically. However, there is loss of billions of liters of water every year due to leakages in water distribution systems. Such water loss means significant financial loss for the utilities as well. World bank estimates a loss of $14 billion annually from wasted water. To address these issues and for the development of efficient and reliable leakage management techniques, high efforts have been made by the researchers and engineers. Over the past decade, various techniques and technologies have been developed for leakage management and leak detection. These include ideas such as pressure management in water distribution networks, use of Advanced Metering Infrastructure, use of machine learning algorithms, etc. For leakage detection, techniques such as acoustic technique, and in recent yeats transient test-based techniques have become popular. Smart Water Grid uses two-way real time network monitoring by utilizing sensors and devices in the water distribution system. Hence, valuable real time data of the water distribution network can be collected. Best results and outcomes may be produced by proper utilization of the collected data in unison with advanced detection and management techniques. Long term reduction in Non Revenue Water can be achieved by detecting, localizing and repairing leakages as quickly and as efficiently as possible. However, there are still numerous challenges to be met and future research works to be conducted in this field.

• 상하수도학회지
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• 제24권5호
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• pp.495-508
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• 2010

The aim of this study is to develop a quantified water loss Index to evaluate and manage leakage scientifically for the reduction of non-revenue water in water distribution systems. For the purpose, unavoidable background leakage suggested from UK water industry and IWA, and allowable water leakage in accord with the concept of allowable water loss are proposed by analyzing the inflow into two study water districts and the short-term water use of each customer in the districts. The study distribution areas are selected among the metered districts with good maintenance of leakage after improvement activities in Nonsan, medium sized city in Korea. Estimation models of allowable leakage are developed by metering and analyzing the minimum night flow at residential and commercial areas in the city. In the results of the investigation, it is estimated that background night flow in residential area was larger than that of commercial area where the types of business shows small water use characteristics. Meanwhile, night flow and background water loss on internal plumbing systems show great differences for each district which is influenced much by the water use characteristics and facilities scale. Based on metering water use data in various districts, leakage management criteria can be established under the consideration of domestic conditions in Korea by analyzing separated real water use and background leakage and it is possible to apply into presentation of optimal leakage level and reasonable time for working activities for leakage reduction.

• 한국수자원학회논문집
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• 제45권12호
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• pp.1201-1211
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• 2012

본 논문은 순차적인 일국 CGE 모형을 구축하여 국가의 온실가스 저감정책과 연계한 물산업 지원 정책의 경제적 파급효과를 분석하였다. 모형은 물산업과 에너지 부문을 세분화하였으며, 온실가스 저감수단으로 탄소세를 도입하였다. 시나리오는 탄소세수를 가계에 이전하는 경우와 물산업에 지원되는 경우로 구축해 모의결과를 비교분석 하였다. 분석결과 물산업 지원 정책은 GDP 기준 약 0.1% 수준의 온실가스 저감 비용을 절감하고 소비와 투자를 확대하는데 기여하는 것으로 나타났다. 그러나 물산업의 에너지 집약도가 높기 때문에 탄소세 부과로 인한 에너지 대체, 비에너지 집약적 산업구조 전환에의 기여도는 미미하였다. 따라서 온실가스 저감정책 하에서 물산업 발전을 위해 에너지 효율개선, 친환경 에너지 개발 및 활용 증진 등 비용효율적인 물산업 정책 추진이 중요할 것이다.