Water Availability Modelling for Supplying Domestic Demand

Abstract

This research intends to build the water availability model for supplying the domestic demand in the Tambak Pocok small dam, Bangkalan, Indonesia. Domestic water demand is analyzed based on the population and the standard of water demand in the administrative service area. To estimate the eater availability from rainfall analyses is used the models of NRECA and F.J. Mock. However, for the process of water simulation and reservoir reliability during the 20 years projection period, the discharge data due to the F.J. Mock and NRECA is generated for 9 years by using the Thomas-Fiering method. Based on the simulation result of small dam reliability by carrying out the simulation process for every discharge data as the generated result along 20 years with the projection period during the 20 years, there is indicated that the discharge data by NRECA has been a failure on 2004, on 2007 with the reliability probability of 100%, and on 2026 with the reliability probability of 25%. However, the reliability probability is 100% from 2007 until 2026 for the whole discharge data simulation. Because there is no discharge data in the field, so the selection of discharge data is carried out by taking the Q_min for each discharge data of the two methods. Therefore, it is obtained that the small dam Q_min of F.J. Mock has a reliability degree of 100% from 2007 until 2026. However, for the small dam Q_min of NRECA, the small dam can still serve the whole population (100%) in 2007, for the next years is decreasing until 25% in 2026.

Keywords: National Rural Electric Cooperative Association, F.J. Mock, reservoir reliability.