In the paper the optimal operation of Hoabinh reservoir for flood control on Hong – Thaibinh river system is presented. The finddings show that in the flood season in 1996 if the operation of gates and outlets of Hoabinh reservoir was made base on the calculated release , the water level at Hanoi would be 12,3 m and the water level of Hoabinh reservoir would be 98 m. | Vietnam Journal of Mechanics, VAST, Vol. 30, No. 3 (2008), pp. 142 – 148 OPTIMAL OPERATION OF HOABINH RESERVOIR FOR FLOOD CONTROLON HONG-THAIBINH RIVER SYSTEM Ngo Huy Can, Nguyen Thanh Don, Nguyen Hong Phong, Nguyen Tuan Anh Institute of Mechanics, VAST, Vietnam Nguyen Van Que Airdefence and Airforce Academy Abstract. In the paper the optimal operation of Hoabinh reservoir for flood control on Hong – Thaibinh river system is presented. The finddings show that in the flood season in 1996 if the operation of gates and outlets of Hoabinh reservoir was made base on the calculated release , the water level at Hanoi would be 12,3 m and the water level of Hoabinh reservoir would be 98 m. So the calculated release from Hoabinh reservoir in August 1996 can be considered as optimal in the mean that the water level at Hanoi can be controlled and the Hoabinh reservoir still have necessary pool for controlling the next floods. 1. INTRODUCTION Optimal operation of reservoirs system for flood control on Hong – Thaibinh river system is a big and complicated problem. In this article the optimal operation of Hoabinh reservoir for flood control on Hong – Thaibinh river system is considered. A linear programming model developed in [1] is applied here for the case of Hoabinh reservoir. It seems to be that the reservoir operation leading from this study is more optimal than the one performed in the flood occurred in 1996 [1], [2], [3]. 2. MATHEMATICAL MODEL The upstream of the Hong river consists of 3 rivers: Da , Thao and Lo. (Fig. 1) The flow in Da river contributes a significant part to flow in Hong river (In flood season 1996 the flow in Da river is about 70% total flow in Hong river). So up to now the Hoabinh reservoir plays a very important role in flood control on Hong -Thaibinh river system. We consider the simple model schematic, which simulate the flow from Tabu to ThaoDa confluence. (Fig. 2) The Hoabinh reservoir is divided into 2 zones, the lower S1 and the upper .
