Water resources planning and management are, more and more, becoming important issue for water use and flood control due to the population increase, urbanization, and climate change. In particular, the estimating and the forecasting inflow of dam is the most important hydrologic issue for flood control and reliable water supply. Therefore, this study forecasted monthly inflow of Soyang river dam using VARMA model and 3 machine learning models. The forecasting models were constructed using monthly inflow data in the period of 1974 to 2016 and then the inflows were forecasted at 12- and 24-month ahead lead times. As a result, the forecasted monthly inflows by the models mostly were less than the observed ones, but the peak time and the variation pattern were well forecasted. Especially, the VARMA model showed very good performance in the forecasting. Therefore, the result of this study indicates that the VARMA model can be used efficiently to forecast hydrologic data and also used to establish water supply and management plan.

In this study, we identified heavy rain damage and rainfall characteristics for each region, and proposed Hazard-Triggering rainfall according to heavy rain damage scale focused on Gyeonggi-do. We classified the damage scale into three groups (total damage, over 100 million won, over 1 billion won) to identify the characteristics of heavy rain damage, and we determined criteria of the rainfall class for each rainfall variable (maximum rainfalls for the durations of 1, 3, 6, 12 hours) to identify the rainfall characteristics. We calculated the cumulative probability of heavy rain damage based on the rain criteria mentioned above to establish the Hazard-Triggering rainfall according to the heavy rainfall damage scale. Using the results, we establish the Hazard-Triggering rainfall for each rain variable according to heavy rain damage. Finally, this study calculated the assessment indicator (F1-Score) for classification performance to test the performance of the Hazard-Triggering rainfall. As the results, the classification performance of the Hazard-Triggering rainfall which proposed in this study was 11%, 30%, 10% higher than the criteria by KMA (Korea Meteorological Administration).

The Science and Technology process focuses on a number of areas where science and technology development provides a major opportunity to innovate water resources management. A number of areas have been carefully selected and are described below. Main focus 1: Efficient water management Today’s water management continues to be highly inefficient in many respects, seriously hampering the sustainable management of water resources, delivery of services and the protection of human health and the environment. In the years to come, major efforts will need to be made to improve water efficiency as a means to secure water resources, adapt to climate change, or operate water services systems at lower costs. Sub Focus: Urban water efficiency, Agricultural water efficiency, Industrial water efficiency, Energy efficiency in water and waste water systems Main focus 2: Resource recovery from water and waste-water systems Increasingly, water and waste-water systems are recognized as potential sources of recovering water, energy, nutrients and other materials. At the same time, the re-use of waste water in agricultural, industrial and urban applications is gaining momentum. The development of re-use and recycling within the water and waste-water sectors provides major opportunities for improving environmental performance, creating climate benefits and reducing costs. Sub Focus: Water re-use and recycling technologies, Energy recovery and production from water and waste water cycles, Nutrients recovery from waste water Main focus 3: Water and Natural disasters As the devastating impact of recent natural disasters such as the flood occurred in Thailand in 2011, indicates, mankind is vulnerable to extreme weather events in developing and even in developed countries. Clearly, such extreme events have always been part of our life and may be caused by climate change. This makes water related problems, especially, such as floods and droughts, more difficult to analyze and predict. Climate change is predicted to have a range of serious consequences, some of which will have impact over the longer term, like droughts, while some have immediate and obvious impacts, such as intense rain and flooding. Floods and droughts are major natural disasters involving loss of life and the destruction of property. So, we may need advanced technologies and measures in order to cope with natural disasters. Sub Focus: Climate change : impact assessment and adaptation, Drought analysis and management, Urban floods and damage reduction studies, RS and GIS applications for natural hazards Main focus 4: Smart technology for Water Water management is increasingly influenced by developments in Smart Technology(ST). Better use of this ST in measuring, monitoring and distributing water can lead to a significant contribution in overcoming water management challenges in the 21st century. Bridging the ‘divide’ between the water and ST sectors will be important in the development and (wide-scale) application of new smart technologies in the water sector. Sub Focus: Urban and Irrigation water management and ST, Integrated and intelligent river basin water management and ST, Design and implementation of smart water grid, Water resources management and Big Data Main focus 5: Understanding and managing ecosystem services for water Ecosystems provide valuable services underpinning water security and the sustainable management of water resources. In recent years, major advances have been made in understanding the role of ecosystems in, for example, reducing floods, recharging aquifers, or protecting and improving water quality. Sub Focus: The science and technology of natural and green infrastructure management, The economic valuation of ecosystem services for water, The payment for ecosystem services for water quality and delivery

본 연구에서는 기상청 산하 30년 이상의 관측치를 갖고 있는 기상관측소 58개 지점을 대상으로, 과거 관측자료 및 대표농도경로(RCP) 시나리오에 의한 강수량 자료를 이용하여 지점 및 지역 확률강수량을 산정하였다. 기후변화 시나리오 자료의 편의를 제거하기 위하여 분위사상법(Quantile Mapping)과 이상치 검정을 실시하였다. 이를 통해 보정된 시나리오 값을 이용하여, 빈도해석을 통한 미래 목표기간별 확률강수량의 변화율을 살펴보았다. 기후변화에 따른 미래 확률강수량은 지속시간 24hr의 경우 현재에 대비하여 RCP 4.5시나리오 에서는 지점확률강수량 값은 평균 14~22%가 증가하였으며, 지역확률강수량 값은 평균 12~22% 증가하였다. RCP 8.5 시나리오에서는 지점확률강수량 값은 평균 8~27%가 증가하였고, 지역확률강수량 값은 7~27% 증가하는 것으로 분석되었다. 기후변화로 인한 강수량의 증가와 도시화에 따른 유출특성 변화로 자연재해 발생 및 피해는 더욱 증가할 것으로 예측된다. 이에, 본 연구에서 제시한 극치통계분석 및 확률강수량 자료는 미래 홍수 안전도 및 방재시설물 설계기준을 수립하는데 기초자료로 활용할 수 있을 것으로 기대된다.

습지는 수질정화, 재해관리, 생물서식처 제공, 기후변화 대응 등의 다양한 기능을 지닌다. 특히 습지는 환경적인 이수기능 뿐만 아니라 유속과 수위를 낮추는 치수기능 목적으로도 활용이 가능하므로 하천변 인공습지의 조성은 홍수조절을 위한 새로운 대안으로 제시되고 있다. 하지만 기존 연구들은 습지의 수질정화 기능과 종의 다양성 등에 생태적 기능에 관한 것이 대부분으로, 인공습지 조성에 따른 홍수조절효과에 관한 연구는 아직 미비한 실정이다. 본 연구에서는 안양천중류 유역에 속하는 목감천에 대하여 인공습지 조성 전과 후의 수리특성 변화를 검토하였다. 이를 위해 안양천중류 유역에 속하는 목감천을 대상유역으로 하여 HEC-HMS 모형을 통한 유출량을 산정하고 수리모형인 HEC-GeoRAS모형으로 가상의 인공습지를 모형화하여 습지 조성 전·후 수위와 유속의 시공간적 분포를 분석하였다. 결과자료를 토대로 대상유역의 인공습지 조성 전·후에 대한 수리특성을 검토하고 수위, 유속 변동에 따른 목감천의 홍수저감효과를 평가하였다. 본 연구는 인공습지 조성 사업 시 사업의 타당성을 평가하며, 설계 시 기초자료로 활용될 수 있을 것으로 기대된다.