Impacts of Upstream Structures on Downstream Discharge in the Transboundary Imjin River Basin, Korean Peninsula

Abstract

The transboundary river basin is a great challenge for water management and disaster reduction due to its specific characteristics. In this study, upstream impacts from natural and artificial sources on the downstream discharge on the Imjin river basin, the well-known transboundary region in the Korean peninsula, were evaluated using a hydrological model integrating a dam operation module at an hourly timescale. The module uses a concept of the AutoROM method as the operational rule to update the dam storage and decide water release. Dam storages were translated into water levels using a water level–storage curve. To quantify the impact of hydraulic structures on the Northern Imjin river basin, change in discharge was analyzed in four flood events (2009, 2010, 2011, and 2012). Dam failure scenarios were developed under conditions of the 2010 flood event, in which the releases of 100%, 80%, 50%, and 20% of water storage of Hwanggang dam were simulated. The results indicate that the amount of water released from upstream dams is the main cause of floods in the downstream region. To reduce the risk of floods in the downstream river basin, an optimal dam operation module and information on upstream dams play an important role and contribute to the effective use of water resources.

Identification and Apportionment of Potential Pollution Sources Using Multivariate Statistical Techniques and APCS-MLR Model to Assess Surface Water Quality in Imjin River Watershed, South Korea

“…South and North Korea on the Korean Peninsula have been divided since the Korean War (25 June 1950-27 July 1953; due to the special situation of the MDL, two countries have jointly occupied the Imjin River [39]. The Imjin River is the seventh largest river on the peninsula, originating from Duryu Mountain, Beopdong-gun, Gangwon Province, North Korea, passing through MDL, joining the Hantan River and Moonsan Stream, joining the Han River in Gimpo-si, Gyeonggi Province, and then flowing into the West Sea [38].…”

Effect of Discharge on Water Quality in Euphrates River Between Hit and Ramadi, Iraq

“…This result reflects the absence of a local discharge source within the study area, which may have reflected the decrease in upstream water resources and an absence or scarcity of local resources within the study area due to the lack of precipitation. Many authors have found that the large dams and reservoirs affect the Euphrates' downstream discharge and flow (Yang et al, 2015;Lee et al, 2019;Thu Ha et al, 2020).…”

“…Nitrate (NO3) concentrations were detected at the monitoring stations from 2.25 to 4.55 mg/L. Human Human activities that can increase nutrient levels in aquatic systems include Human activities that can increase nutrient levels in aquatic systems include atmospheric deposition of nitrogen from fossil fuel combustion, agriculture, and industrial activities (Thu Ha et al, 2020). An increase in nutrient concentration with a low-flow situation is particularly harmful if it occurs at a time of the biological activity of living organisms, such as in spring or summer (Lawrence & Gresens, 2004).…”

Sentinel-1 SAR Time Series-Based Assessment of the Impact of Severe Salinity Intrusion Events on Spatiotemporal Changes in Distribution of Rice Planting Areas in Coastal Provinces of the Mekong Delta, Vietnam

“…Such a situation is more severely affected during the dry season when rainfall decreases and river flows are insufficient to repel the saline water, a phenomenon characterized by the appearance in the dry season in coastal areas, but rarely in the upper part of the MD. In addition, the upstream dams influence the discharge through water control [32,33], such as storing water during the rainy season in order to ensure the normal operation of power generation during the dry season [49]. However, it may also impair downstream discharge and irrigation water resources during dry season [33,50].…”