• Proceedings of the Korea Water Resources Association Conference
• /
• 2018.05a
• /
• pp.305-305
• /
• 2018

저수지 상류부 환경변화 분석을 위해 환경변화 시나리오 적용 분석할 수 있는 수문모형(SWAT)을 선정하여 수양(함동)호 유역을 포함하는 송산관측소를 유역출구로 하여 유출량 자료가 있는 2015~2016년을 대상으로 모형을 검?보정하였다. 수양(함동)호는 댐 높이 13.5m에서 15.1m로 증고 되었으며 총저수량은 7,472 천$m^3$에서 11,926 천$m^3$로 증가하였다. 모형 검증결과 모형효율이 0.9로 모형 적용가능성을 확인하였으며 둑높이기 사업 전(2001-2010)과 사업 후(2015-2016)을 모의하여 사업 전?후의 수문요소(강우, 유출, 침투, 증발산, 침루, 토양수분, 지하수 증발, 지하수함양) 모의결과를 정리하였다. 사업 전(2001-2010) 평균 강수량 1549.8 mm, 유출량 907.9 mm, 침투량 615.4 mm, 증발산량 624.2 mm, 침루량 241.1 mm, 토양수분 355.7 mm, 지하수 함양량 222.5 mm로 모의 되었다. 사업 후(2015-2016) 평균 강우량 1100.1 mm, 유출량 370.4 mm으로 극심한 가뭄으로 나타났다. 사업 전 비슷한 강우량을 나타낸 2006년 지하수 함양량은 186.9 mm이고 2016년은 222.9 mm로 지하수 함양량이 사업 후 증가한 것으로 판단된다.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.4
• /
• pp.1389-1400
• /
• 2013

This study developed an operating rule curve (ORC) for multipurpose water supply (irrigation and environmental water) in heightened agricultural reservoir. Among the 20 reservoirs in improvement project of agricultural reservoir dam heightening, the 4 representative reservoirs (Ungyang, Gungchon, Yongam and Unam) were selected for the study according to the analysis of statistical characteristics. Available environmental water supply amounts during irrigation and non-irrigation periods, which is the range from release restricted water level to high water level were estimated by water balance analysis using reservoir operation model. Reliability, resiliency and vulnerability criteria for water system performance were used to assess the multiple water supply capacity. The ORC was presented as the percentile rank for the daily reservoir water level from the results of reservoir operation using the past couple of decades weather data. The water levels for each percentile were divided into 3 buffer sections representing drought (5~25%), normal (25~75%), and flood (75~95%) year to operate the heightened agricultural reservoir with ORC.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.560-560
• /
• 2015

우리나라 연평균 수자원 총량은 1,297억톤이고 이용가능한 수자원량은 58%(753억톤)이며, 이 중 바다로 유실되는 32%(420톤)를 제외하고 연간 26%(333억톤)을 이용하고 있다. 용도별로 보면 생활용수 75억톤, 공업용수 21억톤, 농업용수 159억톤 및 유지용수 78억톤 등으로 사용되며 농업용수가 약 48%로 가장 많은 양이 차지하고 있다. 농업용수는 국내 수자원 소비량 중 가장 많은 양을 차지하고 있으나, 주기적인 가뭄에 따른 용수 부족이 매년 심각한 문제로 대두되고 있는 실정이며, 이에 대한 대책으로 저수지 준설, 둑 높이기, 다단계 양수장 건설 등을 통한 저수량 확보 사업이 진행되고 있으나 준설 및 둑 높이기시 막대한 사업비와 양수장 조성 공간 부족 등으로 농업용수 확보에 어려움이 발생하고 있다. 국내에서는 수자원 개발 및 친수공간 조성을 목적으로 매년 1,000여건의 하천공사가 실시되고 있으며, 하천공사로 인해 가물막이의 설치 및 해체가 계속적으로 발생하고 있다. 하천공사시 가물막이 설치를 위해 중장비의 출입 반드시 필요하나 중장비 출입이 어려운 지역에서는 공사기간 지연 및 경제성 등의 문제로 어려움을 겪고 있는 실정이다. 이에, 본 연구에서는 휴대용 차수막의 구조개선을 통해 (1) 저수지 증고 및 하천 가물막이에 적합한 설계 및 설치 방법을 개발하고, (2) 수압 및 부유물질에 안전하도록 강도를 개선하였으며, (3) 내구성, 경제성, 유지관리성이 개선된 재이용이 가능한 휴대용 차수막을 개발하였다. 휴대용 차수막 개발로 인해 저수지 증고 및 하천 가물막이 뿐만 아니라 방재 및 레크레이션용도 등 다목적 활용이 높은 것으로 나타나 수자원 분야에 다수 적용될 것으로 기대된다.

• KCID journal
• /
• v.18 no.2
• /
• pp.66-75
• /
• 2011

Multivariate statistical analysis was applied to 110 dam heightening reservoir to classify the building conditions for waterfront centered around cultivated area using data of land cover, landscape, additional water quantity, local economic, tourism resources, and accessibility related variables. Five factors were extracted through factor analysis based on eigen value criteria of more than one. These five factors together account for 68.2% of the total variance. Characteristics of five factors for the downstream of dam heightening reservoirs are building conditions of waterfront, economic conditions, additional water quantity, eco-tours, and accessibility of tourism resources respectively. Five clusters were classified through cluster analysis based on factor score. The classified result shows that third cluster has remunerative terms for building waterfront.

• KCID journal
• /
• v.19 no.1
• /
• pp.30-39
• /
• 2012

In recent years, there have been a lot of severe flood and drought disasters and the rural environment have been worsened due to rapid industrialization and urbanization in the river basins of Korea. To prevent such disasters and to improve environment in the era of climate change, Korean Government carried out 110 projects to heighten irrigation dam in the rural area. The study has been carried out to evaluate the heightening work of the irrigation dam for the supply of reserved water and to derive optimal scheme to allocate the water resource for irrigation, domestic demand and environmental conservation as well as to contribute for the rural development in sustainable way. The study is focused on the Seoam Irrigation Dam which has been constructed in 2005 to be connected with the new Gami Reservoir which has been constructed since 2010. In addition, it was studied the contribution effect of the reservoirs for the adjacent comprehensive rural development projects which have been executed by local government. In the study, the principles and visions of sustainable development which have been derived by International Commission on Irrigation and Drainage is applied to estimate the sustainability of the irrigation dams in line with the adjacent comprehensive rural development projects. The project is estimated that the water resource in the reservoirs shall be used integratedly in cooperation with various stakeholders not only to conserve water environment but also to increase productivity of agricultural goods and ecological tour in the rural area.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.55 no.3
• /
• pp.51-62
• /
• 2013

The importance of environmental water has been risen in terms of river ecosystem soundness with preventing stream flow depletion in rural area, while enlarging agricultural reservoir project is conducted under the 4 main river restoration project for supplying more water to 4 main rivers. The aim of this study was to estimate the amount of environmental water release and analyze the release pattern during non-irrigation season in enlarged agricultural reservoirs. The 4 reservoirs (Dansan, Samga, Geumbong, Changpyeong) located on the upper region of Nakdong river were simulated applying the operation rule which was determined by release criteria curves. The simulated results indicated that the more environmental water could be released than the spillway release and continuous release was achieved with smaller range of fluctuation. In case of Changpyeong reservoir, average 506.0 thousand $m^3$ environmental water could be released on Feb., and it was about twice as much as the spillway release before the enlargement, and also, the 18 thousand $m^3$/day environmental water could be supplied to a stream consistently after enlargement. From the results, it was expected that the additional environmental water release will improve stream water flow during dry season in terms of quantity and quality of water.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.54 no.5
• /
• pp.17-24
• /
• 2012

The main purposes of the agricultural reservoir enlargement (ARE) project are to secure water supply reliability (WSR) for agriculture and to release environmental water during dry seasons. In this study, an operational rule that will simultaneously satisfy both the above issues was developed. Initial amount of water storage at the beginning of non-irrigation season (1st October) was divided into 3 stages, and the target level of water storage at the beginning of irrigation seasons (1st April) was set up. Required operational curves and release amounts were estimated based on the stages and target water levels. To evaluate the applicability of this rule, the amount of water released for environmental purposes and WSRs were analyzed for three reservoirs (Unam, Jangchi and Topjeong). The ratio between annual amount of release and additional amount of water storage were 1.6, 1.85, and 4.1 for the Unam, Jangchi, Tapjeong reservoirs, respectively. Also, the WSRs of all reservoirs were found to become higher than when the design standard was applied. Therefore, it is considered that the proposed rule is more suitable for the enlarged agricultural reservoirs operation as it satisfies the WSRs while securing the environmental water release.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.59 no.1
• /
• pp.31-43
• /
• 2017

Recent studies about irrigation water use have focused on agricultural reservoir operation in irrigation period. At the same time, it is significant to store water resource in reservoir during non-irrigation period in order to secure sufficient water in early growing season. In this study, Representative Concentration Pathways (RCP) 4.5, 8.5 scenarios with the Global Climate Model (GCM) of The Second Generation Earth System Model (CanESM2) were downscaled with bias correlation method. Cumulative precipitation during non-irrigation season, October to March, was analyzed. Interaction between cumulative precipitation and carry-over storage was analyzed with linear regression model for ten study reservoirs. Using the regression model, reservoir drought response ability was evaluated with expression of excess and deficiency. The results showed that future droughts will be more severe than past droughts. Especially in case of non-exceedance probability of 10%, drought in southern region seemed to be serious. Nine study reservoirs showed deficiency range from 10% to 55%, which turned out to be vulnerable for future drought. Only Jang-Chan reservoir was secure for early growing season in spite of drought with deficiency of 8% and -2%. The results of this study represents current agricultural reservoirs have vulnerability for the upcoming drought.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.528-532
• /
• 2017

영산강은 우리나라에서 호남평야 다음으로 넓은 나주평야에 농업용수를 공급하는 남도의 젖줄이며 영산강 유역민의 약 70%가 거주하는 약 150만의 광주광역시를 관통하는 우리나라 4대강의 하나이다. 그러나 영산강은 그 위상에 맞지 않게 우리나라 하천 중 수질이 가장 악화되어 있는 하천 중 하나이다. 영산강의 수질은 최근 10여 년 동안에 이루어진 수질오염총량관리제의 제 1단계(2004~2010년), 제 2단계(2011~2015년) 사업과 2012년 10월 광주광역시의 총인처리시설의 정상 가동, 영산강의 수질을 2급수(좋은 물) 목표로 4대강 사업의 일환으로 갈수기 유지유량 공급을 위하여 14개 농업용저수지의 둑 높이기 사업 등 배출오염부하량의 삭감노력과 하천유지유량의 증대계획 등으로 많이 개선되어 왔으나, 1~2급수를 유지하는 3대강 수준에 크게 못 미치는 3~4급수의 수질을 유지하며 상대적인 수질악화와 그 격차가 크게 차이를 보이며 고착화되고 있다. 따라서 본 연구에서는 4대강 사업의 일환으로 숭상이 이뤄졌고, 영산강의 수질에 비해 상대적으로 청수인 영산강유역의 4대호 담양댐, 광주댐, 장성댐, 나주댐의 호소수를 영산강에 추가로 방류할 경우 수질이 개선되는 정도를 분석하여 제시하였다. 수질개선효과를 분석하기 위하여 QUAL-MEV모델을 이용하여 영산강 수질모델을 구축하였고, 목표연도 2020년을 설정하여 4대호 방류구의 현재의 지리적 위치와 4대호의 수질자료를 모델에 직접 입력하여 추가 방류량의 변화에 따라 수질개선효과를 분석하여 그 문제점을 제시하였으며, 4대호 댐별로 영산강의 수질개선 기여도를 분석하여 제시하였다.

• Korean Journal of Ichthyology
• /
• v.36 no.1
• /
• pp.48-57
• /
• 2024

Distribution status and extinction threat evaluation of an endangered species, Cobitis choii, were investigated from 2015 to 2019. In 2015 and 2018, we investigated past appearance sites of C. choii. In 2015, 163 individuals from nine sites were collected by surveying 19 stations. In 2018, 19 individuals from five sites were collected by surveying 22 sites. In 2019, 156 individuals from 12 sites were collected as a result of a survey of 79 sites of past appearance and potential appearance of C. choii. Appearance regions were Mihocheon (Baekgokcheon (2 sites), Chopyeongcheon (1 sites)), Gapcheon (3 sites), Yugucheon (2 sites), Jicheon (4 sites), and Geumgang mainstream (2 sites). Among these appearing regions, Baekgokcheon, Yugucheon, and Mihocheon mainstreams showed a sharp decline in population. Baekgokcheon was estimated to have a habitat change due to a project to raise the bank of Baekgok Reservoir. Yugucheon was estimated to have a habitat disturbance due to flood-induced collapse and reconstruction of weir. Mihocheon mainstream was estimated to have water pollution and habitat disturbance. On the other hand, Chopyeongcheon and Geumgang mainstream were newly habitat identified and Gapcheon was noted to show an increase in the number of individuals. After performing extinction threat evaluation, C. choii was evaluated as Endangered (EN A2ac) due to its rapid population decline (more than 50%) in its habitats of Baekgokcheon, Yugucheon, and Mihocheon based on criteria A, while it was evaluated as Vulnerable (VU B1ab (iii,v) +B2ab +B2ab (iii,v)) due to its narrow extent of occurrence (EOO, 1,735 km²) and area of occupancy (AOO, 36 km²) in 6 locations with a continuous population decline based on criteria B. Therefore, the final threat of extinction grade was evaluated as Endangered (EN A2ac). In Baekgokcheon, Yugucheon, and Mihocheon mainstream where the population has declined rapidly recently, conservation measures are urgently required to increase its population.