Modification and application of Water Supply Capacity Index for daily drought monitoring of a reservoir

Jang Won Moon

doi:10.3741/JKWRA.2026.59.3.285

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2026 Vol.59, Issue 3 Preview Page Next Page

Research Article

Modification and application of Water Supply Capacity Index for daily drought monitoring of a reservoir 일 단위 저수지 가뭄 감시를 위한 물공급능력지수의 개선 및 적용

31 March 2026. pp. 285-294

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Abstract

This study evaluates supply-based drought characteristics of reservoir systems using a Water Supply Capacity Index (WSCI) derived from daily reservoir storage data. The WSCI represents the number of days that water supply can be sustained under the assumption of no additional inflow, providing an intuitive indicator of current supply capability. Daily WSCI values were calculated for 21 multipurpose and water-supply dams in South Korea. Cumulative distribution analyses were conducted to compare supply characteristics among dams, and a 90-day threshold was applied to assess drought risk. Reliability, vulnerability, and recovery characteristics (R-V- RC) were also quantified. The results show that large multipurpose dams generally exhibit high supply reliability, while several small and medium-sized dams display higher vulnerability and longer recovery periods. The proposed WSCI-based framework provides a practical indicator for identifying a golden time for drought response prior to severe supply shortages and can support proactive reservoir operation and drought management.

Keywords

Drought

WSCI

Reservoir

Supply-based drought

Drought management

본 연구에서는 일 단위 저수량 자료를 활용하여 물공급능력지수(Water Supply Capacity Index, WSCI)를 산정하고 이를 통해 댐의 공급 기반 가뭄 특성을 분석하였다. WSCI는 특정 시점의 저수량을 기준으로 추가 유입이 없다고 가정할 경우 공급 가능한 일수를 나타내는 지표로, 공급 관점의 가뭄 상황을 직관적으로 제시하는 지표이다. 국내 21개 다목적댐 및 용수전용댐을 대상으로 WSCI를 산정하고 누가확률분포 분석을 통해 댐별 공급능력 특성을 비교하였다. 또한 공급가능일수 90일을 임계값으로 설정하여 임계값 초과확률과 신뢰도, 취약도, 회복특성(R-V-RC)을 분석하였다. 그 결과, 대형 다목적댐은 전반적으로 높은 공급 안정성을 보였으며, 일부 중·소규모 댐에서는 공급 취약성이 뚜렷하게 나타나고 있음을 확인하였다. 본 연구에서 제시한 WSCI 기반 접근은 실제 물 공급 장애 발생 이전에 대응 조치를 준비할 수 있는 가뭄 대응의 ‘골든타임’을 제시한다는 점에서 의의가 있으며, 댐 운영 및 가뭄 대응 정책 수립을 위한 기초 자료로 활용될 수 있을 것으로 기대된다.

키워드

가뭄

물공급능력지수

저수지

공급 기반 가뭄

>가뭄 대응

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Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 59
No :3
Pages :285-294
Received Date : 2025-12-18
Revised Date : 2026-01-22
Accepted Date : 2026-01-27
DOI :https://doi.org/10.3741/JKWRA.2026.59.3.285

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

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