Page - 551 - in Book of Full Papers - Symposium Hydro Engineering

Discharge Jan Feb Mar Apr May Jun Jul Ags Sep Oct Nov Dec (m3/s) Q > 9,5 75 120 36 16 12 0 5 6 7 8 16 16 Q > 29 0 8 1 0 0 0 0 0 0 0 0 0 Q> 46,8 0 5 0 0 0 0 0 0 0 0 0 0 The Frequency of Occurrence (time) Table 4 Flood Frequency in One Year at Sukamahi Dam Fig. 5 Flood Frequency in One Year at Sukamahi Dam From the data above, it can be known that the wet season pattern starts from November to April and dry season is May to October. 3. ANALYSIS OF FLOOD CONTROL IN CIAWI AND SUKAMAHI DAM As stated previously, Ciawi Dam and Sukamahi Dam are planed as flood control measures. To optimize the flood reduction, the reservoir water level should be in low condition, where the water flows freely through tunnel. Flood routing calculation result for flood return period 2 yr, 5 yr, 10 yr, 20 yr, 25 yr, 50 yr, 100 yr and QPMF at Ciawi Dam and Sukamahi Dam in fully opened tunnel condition as presented in the next figure. 551