DETERMINING OPERATION PERIODS FOR FLOOD CONTROL IN CA RIVER BASIN

Abstract

The Ca river basin is located in the North Central Coast climate. Therefore, the flood season in the basin is differentiated among regions and have a tendency on later appearance with a shorter duration from North to South. The paper has applied the classification and divergence method of floods at typical hydrological stations including Cua Rao, Nghia Khanh, Dua, Nam Dan, and Hoa Duyet to identify different flood periods including early floods, main floods, and late floods. This is the proposed basis for the operation mechanism of reservoirs in the Ca River basin in the reduction of downstream floods. As a result, Cua Rao station has an early flood period of 48 days, main flood period of 61 days, and late flood period of 44 days. Nghia Khanh station has an early flood period of 79 days, main flood period of 74 days, and late flood period of 15 days. Dua station has an early flood period of 50 days, main flood period of 98 days, and late flood period of 25 days. Nam Dan station has an early flood period of 50 days, main flood period of 109 days, and late flood period of 24 days. Hoa Duyet station has an early flood period of 69 days, main flood period of 90 days, and late flood period of 24 days.