Page - 285 - in Book of Full Papers - Symposium Hydro Engineering

Table 5 Flushing Cost Calculation Discription Unit Volume Unit Price (Rp) Amount (Rp) Sediment FLushing = 350,865 m3 Loss of Water Service Fee (kWh) 969,000 167.0 161,823,000 Loss of Electricity Service (kWh) 969,000 1,352 1,310,088,000 Cost of Flushing Implementation Lump sum 1 133,330,000 133,330,000 Damage of Water Resource Infrastructure - Total Cost of Flushing 1,605,241,000 Table 6 Dredging Cost Calculation Description Explanation A. Land Acquisition Cost Land acquisition Rp 290,000/m2 Spoil bank can accommodate sediments 10 m high Land Acquisition Cost = 290,000 / 10 = Rp 29,000 / m3 Spoilbank Embankment Construction For the sediments of 1 m3 the volume of spoil bank embankment is = 1/3 = 0.333 m3 Unit price of embankment is Rp 40,930 / m3 Calculation see attachment 1 Spoil bank embankment construction cost = 0.333 x 40,930 = Rp 13,630 / m3 Sediment Dredging Costs Sediment dredging cost = Rp 64,100 / m3 Calculation see attachment 2 Dredging with Spoil Bank Disposal Costs = A + B + C = Rp 106,730 / m3 For dredging of 350.865 m3 of sediment cost = 350,865 x106,730 = Rp 37,454,838,750 Dredging with Riverine Disposal to Channel Below Costs = C = Rp 64,100 / m3 For dredging of 350.865 m3 of sediment cost = 350,865 x 64,100 = Rp 22,490,446,500 From the above table it can be concluded that flushing implementation is more effective than dredging. Flushing can save the cost of Rp. 35.85 billion (Rp 37,454,838,750 – Rp 1,605,241,000) compared to dredging with spoil bank disposal, while dredging with riverine disposal to channel below can save about Rp. 14.96 billion (Rp 37,454,838,750 – Rp 22,490,446,500) compared to the dredging with spoil bank disposal. 285