Development and Evaluation of the Hydropower Reservoir Rule Curve for a Sustainable Water Supply

Abstract

The Seoul metropolitan area in the Han River basin is searching for sustainable water supply options after recently experiencing an extreme drought. Building a new reservoir is a common way to alleviate water shortage, but this comes at a great environmental cost. The South Korean government granted permission to add on a water supply function for the Hwacheon Reservoir, the largest hydropower reservoir in Korea, for the first time in the history. This study develops a new rule curve for the Hwacheon Reservoir to supply water and generate energy at the same time, considering the status of other reservoirs in the Han River basin. The simulation model uses two scenarios, with scenario 1 simulating historic operation and scenario 2 applying the deficit supply method. The new rule curve was formulated based on the results from scenario 2. Time-based and volumetric reliability increased by 33% and 4%, respectively, and resiliency more than doubled compared to the historic reservoir operation. This is the first case study in South Korea that demonstrates how to successfully integrate a water supply function into an existing hydropower reservoir. This study can be applied and extended to other river basins in an attempt to alleviate water shortages by adding new functions to existing reservoirs.

Optimal Operation of Nashe Hydropower Reservoir under Land Use Land Cover Change in Blue Nile River Basin

“…In reservoir system analysis, the basic modeling approaches utilized to provide quantitative information that can improve operational water management are descriptive simulation, prescriptive optimization, and hybrid models [30]. Optimization algorithms have been used to solve water resource management problems, and to find the best rule curves, optimize the storage and release by minimizing total penalty functions at designated locations throughout the water resource network [31,32]. The descriptive simulation models describe reservoir system performance under a given set of control actions [30,33].…”

Flood Vulnerability Assessment of an Urban Area: A Case Study in Seoul, South Korea

“…The growing impervious surface area in Seoul has resulted in inundation damage almost every year, as the terrain conditions are unfavorable for draining rainwater during storm events [31][32][33][34]. During heavy storms, Seoul faces casualties and property losses [35].…”

Development of an Optimal Water Allocation Model for Reservoir System Operation

“…Several studies have aimed to estimate the volume of water that the Hwacheon Reservoir could provide with a 95% reliability for water supply. This initiative led to the development of a Hwacheon Reservoir rule curve specifically for drought conditions [21]. Another study proposed estimating the water supply capacity for an individual reservoir by incorporating operational aspects of hydropower reservoirs into a reservoir operation model [22,23].…”