Effectiveness in storing and reducing floods of the red river upstream reservoirs under the incident of Lienmac dyke

Abstract

The Red river and Thai Binh river’s dyke system includes 56 dikes classified from grade III to special grade with a total length of 2.207,75km which 37.709km of special grade, 553.70km of grade I, 502,43km of grade II and grade III. At the present, on the Red River and Thai Binh River systems, there are 230 existing weak locations, which have not been completely reinforced yet. It might cause unsafety situations of large flood flush and high water levels of rivers for a long time. Therefore, studying the solutions to support the response under unsafety situations of the dike system is a significant meaning topic. The present paper aims to evaluate the effectiveness of solutions using reservoirs at the Red river upstream in order to store and reduce floods in downstream. This also supports the effort to respond the urgent situations upstream such as huge floods, dyke failures in downstream and dyke failure at Lien Mac. In the scope of this paper, one and two-dimensional hydraulic simulation method was utilized, which describes the scenarios to regulate the upstream reservoir of the Red River and hydraulic calculation of the downstream river network. Then, the effectiveness of flood reduction in each scenario can be estimated. Simulation results show that depending on the calculation scenarios, the capacity of reservoirs can be 5.553 million m3 to cut and reduce flood for downstream. The flooded area might be decreased by 47.528 ha in case using a part of the capacity of the construction. The time when the reservoirs completely close the floodgates and do not discharge the flood into downstream is from 27 to 30 hours, this is an important time for the Lien Mac dike to be completely sealed within 24 hours. The time when the reservoirs completely close the floodgates and do not discharge the flood into downstream is from 27 to 30 hours, this is an important time for the Lien Mac dike to be completely closed within 24 hours.

1. Introduction

2. Data and Methodology

2.1. MIKE 11model

2.2. MIKE flood model

2.3. Simulation and calculation scenario

3. Results and discussion

3.1. Effectiveness of flood reduction at downstream

3.2. Effectiveness of reducing downstream flood as occurring Lien Mac dyke incident

3.2.1. Calculating the process of flood flush for reservoirs

3.2.2. Evaluation of the effectiveness of flood reduction in the downstream area

4. Conclusions

References

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► See detail:   Effectiveness in storing and reducing floods of the red river upstream reservoirs under the incident of Lienmac dyke

Dang Giap Nguyen¹, Cong-Binh Dao², Viet- Chinh Mai²,*

¹Key Laboratory of River and Coastal Engineering, Viet Nam Academy for Water
Resources, Hanoi 100000, Vietnam
²Department of Civil and Industrial Engineering, Institute of Techniques for Special
Engineering, Le Quy Don Technical University, Hanoi 100000, Vietnam
*Corresponding author’s e-mail: maivietchinh@lqdtu.edu.vn

IOP Conf. Series: Materials Science and Engineering 1289 (2023) 012099