소형저수지 안정성 평가를 위한 여유고 산정 = Calculation of Free Board for Evaluating Stability of Small Reservoirs

다국어 초록 (Multilingual Abstract)

Due to the recent climate change, damages such as river levees and reservoir overflows, flooding of agricultural land, and landslides caused by typhoons and local heavy rains have frequently occurred. According to the 2022 Statistical Yearbook of Agricultural Production Base Maintenance (2023), 14,877 out of about 17,066 agricultural reservoirs have been built for more than over 50 years old, and it is unlikely to respond to rainfall events caused by recent abnormal climates. Four reservoirs with at least 30 years old of weather observation data were selected among small reservoirs located in Chungcheongbuk-do, and since there are differences in the observation timing of weather data for each observatory, this study selected a period from 1973 to 2023 (51 years) to compare and analyze the results during the same period. To calculate the design flood amounts, the K-HAS (KRC Hydrology & Hydrology Analysis System) provided by the Korea Rural Community Corporation (KRC) was utilized. Flood amounts were calculated, and reservoirs were tracked using this system. The appropriateness of the target reservoirs was examined based on changes in design flood amounts and reservoir tracking results according to the set period. As a result of analyzing the design flood increase/decrease rate by collecting meteorological data on the target reservoir of this study from 1973 to 2023 and classifying CASE into four categories, the largest increase rate was found in Satteo Reservoir Case 3 (-4.33%), Sojuk Reservoir Case 3 (23.77%), Neolakgol Reservoir Case 4 (15.18%), and Gojabae Reservoir Case 4 (72.58%). It can be seen that the rainfall is gradually increasing even considering the regional specificity. In addition, as a result of examining whether the height of the dam cest for each reservoir is adequate by performing flood tracking of the reservoir based on the design flood calculated to examine the hydrological stability of the target reservoir, it was confirmed that the dam cest height of the Satteo Reservoir Case 3 (-0.50m), Sojuk Reservoir Case 2 (-1.06m), Neolakgol Reservoir Case 4 (-0.53m), and Gojabae Reservoir Case 4 (-0.92m) were found to be the most insufficient. In all this study, the lack of height of the reservoir embankment due to changes in design standards and the increased precipitation is confirmed, and accordingly, measures and operational management measures need to be established to improve the hydrological stability of small reservoirs. Key words: Probability rainfall, aging reservoir, K-HAS, flood volume, dam cest, freeboard * A thesis for the degree of Master of Engineering in February 2025.

목차 (Table of Contents)

• Ⅰ. 서 론 1
• 1.1 연구의 배경 및 목적 1
• 1.2 국내·외 연구 동향 3
• 1.3 연구 방법 및 범위 5
• Ⅱ. 수문학적 검토를 위한 이론적 배경 6
• 2.1 농업용 저수지 현황 6
• 2.2 농업용 저수지 설계기준 10
• 2.3 설계강우 및 홍수량 산정방법 14
• 2.3.1 설계강우 산정방법 16
• 2.3.2 홍수량 산정방법 20
• 2.3.3 저수지 홍수추적 방법 31
• Ⅲ. 대상 저수지 선정 및 자료구축 36
• 3.1 대상 저수지선정 36
• 3.2 저수지 기본자료 구축 37
• 3.2.1 샛터저수지(충북 보은군) 37
• 3.2.2 소죽저수지(충북 영동군) 38
• 3.2.3 느락골저수지(충북 제천시) 39
• 3.2.4 고자배저수지(충북 괴산군) 40
• 3.3 확률강우량 및 홍수량 산정 41
• 3.3.1 샛터저수지 확률강우량 및 홍수량 산정 42
• 3.3.2 소죽저수지 확률강우량 및 홍수량 산정 51
• 3.3.3 느락골저수지 확률강우량 및 홍수량 산정 60
• 3.3.4 고자배저수지 확률강우량 및 홍수량 산정 69
• Ⅳ. 홍수량 변동 및 저수지 홍수추적 78
• 4.1 홍수량 변동분석 78
• 4.2 저수지 홍수추적 82
• 4.3 분석결과 94
• Ⅴ. 결 론 97
• 참고문헌 99