KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Estimation of the Hydrological Design Frequency of Local Rivers Using Bayesian Inference and a Sensitivity Analysis of Evaluation Factors

평가인자 가중치에 대한 베이지안 추론과 민감도 분석을 통한 적정 하천설계빈도 결정

  • 유재희 (한양대학교 대학원 건설환경시스템공학과) ;
  • 김지은 (한양대학교 대학원 건설환경시스템공학과) ;
  • 이진영 (한국농어촌공사 통합물관리추진단) ;
  • 박경운 (한양대학교 대학원 건설환경시스템공학과) ;
  • 김태웅 (한양대학교(ERICA) 건설환경공학과)
  • Received : 2022.01.05
  • Accepted : 2022.05.28
  • Published : 2022.10.01
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Abstract

In Korea, annual precipitation and its variability have gradually increased since modern meteorological observations began, and the risk of disasters has also been increasing due to significant regional variations and recent abnormal climate conditions. Given that damage from storms and floods mainly occurs around rivers, it is crucial to determine the appropriate design frequency for river-related projects. This study examined existing design practices used to determine hydrological design frequencies and suggested a new method to determine appropriate design frequencies. The study collected available data pertaining to seven evaluation factors, specifically the basin areas, shape parameters, channel slopes, stream orders, backwater effect reaches, extreme rainfall frequencies, and urbanized flood inundation areasfor 413 local rivers in Chungcheongnam-do in Korea. The estimated weights for areas of extreme rainfall frequencies and urbanized flood inundation were found to be 18, having a great effect on determining the design frequency. Compared with the established design frequency in previous government reports, the estimated design frequency increased for 255 rivers and decreased for 158 rivers.

우리나라는 기상관측 이래 연평균 강수량과 변동성은 점진적으로 증가하는 추세이고, 지역 간 편차가 크다. 또한, 최근의 이상기후로 인하여 재해에 대한 위험도가 증가되고 있는 실정이다. 풍수해의 피해는 주로 하천주변에서 발생하기 때문에 하천기본계획을 수립하기 위해서는 우선적으로 적정한 설계빈도를 결정하는 과정이 반드시 필요하다. 본 연구에서는 설계빈도 결정에 대한 기존 방법론을 분석하여 문제점 및 개선 방향에 대해 제시하였다. 충청남도에 위치한 지방하천 중 자료구축이 가능한 하천인 413개소를 대상으로, 7개의 평가인자(유역면적, 형상계수, 하도경사, 수계차수, 배수영향 구간, 이상강우 발생빈도, 시가화 침수면적)를 선정하고, 베이지안 추론을 통해 가중치를 산정하였다. 그 결과, 이상강우 발생빈도 및 시가화 침수면적의 가중치가 각각 18로 가장 크게 산정되어, 하천 설계빈도 결정에 큰 영향을 미치는 것으로 판단된다. 이러한 가중치를 통해 설계 빈도를 추정한 결과, 기수립 설계빈도보다 본 연구에서 추정된 설계빈도가 증가하는 하천은 255개이고 감소하는 하천은 158개로 나타났다.

Keywords

Acknowledgement

본 연구는 행정안전부 극한재난대응기반기술개발사업(2020-MOIS33-006)의 지원을 받아 수행되었습니다.

References

  1. Chen, Z. M., Yeh, Y. L. and Chen, T. C. (2018). "Assessment of a regional flood disaster indicator via an entropy weighting method." Natural Hazards Review, Vol. 19, No. 2, 05018002. https://doi.org/10.1061/(ASCE)NH.1527-6996.0000280
  2. Chungcheongnam-do (2017). Determination of the optimal return period for river design in Chungcheongnam-do (in Korean).
  3. Joo, H. J., Lee, T. W., You, Y. H., Wang, W. J., Kim, S. J. and Kim, H. S. (2019). "Determination of investment priority for flood control using flood risk and economic assessments." Journal of The Korean Society of Hazard Mitigation, KSHM, Vol. 19, No. 6, pp. 291-301 (in Korean).
  4. Lee, E. H., Choi, H. S. and Kim, J. H. (2015). "Determination of flood risk considering flood control ability and urban environment risk." Journal of Korea Water Resources Association, KWRA, Vol. 48, No. 9, pp. 757-768 (in Korean). https://doi.org/10.3741/JKWRA.2015.48.9.757
  5. Lee, J. H., Jun, H. D., Choi, J. W. and Park, J. B. (2018). "Evaluation of urban small watershed relative flood risk using multi criteria decision making method." Journal of The Korean Society of Hazard Mitigation, KSHM, Vol. 18, No. 2, pp. 431-438 (in Korean).
  6. Ministry of Land, Infrastructure and Transport (MOLIT) (2016). Comprehensive water resources plan (in Korean).
  7. Ministry of Land, Infrastructure and Transport (MOLIT) (2018). List of rivers in Korea (in Korean).
  8. Ministry of Land, Infrastructure and Transport (MOLIT) (2019). River design standards and commentary (in Korean).
  9. Ministry of Land, Transport and Maritime Affairs (MLTM) (2008). Guideline for basinwide flood mitigation plan (in Korean).
  10. Ministry of the Interior and Safety (MOIS) (2019). Disaster annual report (in Korean).
  11. Ryu, J. H., Kim, J. E., Lee, J. Y., Kwon, H. H. and Kim, T. W. (2022). "Estimating optimal design frequency and future hydrological risk in local river basins according to RCP scenarios." Water, Vol. 14, No. 6, 945. DOI: https://doi.org/10.3390/w14060945.
  12. Ryu, J. H., Lee, J. Y., Kim, J. E. and Kim, T. W. (2018). "Determination of the optimal return period for river design using Bayes theory." Journal of the Korean Society of Civil Engineers, KSCE, Vol. 38, No. 6, pp. 793-800 (in Korean). https://doi.org/10.12652/KSCE.2018.38.6.0793
  13. Yoo, S. W. and Kim, I. G. (2020). "A study on the estimation of launch success probability for space launch vehicles using Bayesian method." Journal of the Korean Society for Aeronautical & Space Sciences, Vol. 48, No. 7, pp. 537-546 (in Korean).