Performance evaluation of the Nipa-Nipa treatment plant (Indonesia)

Based on the results of laboratory tests on the quality of wastewater from the Nipa-Nipa Sludge Treatment Plant (STP) effluent, several parameters were still found that were not in accordance with the standards. In this context, the analysis of the design criteria of the plant was carried out in this study. Furthermore, Net Present Value (NPV), the Benefit Cost Ratio (BCR), and the Internal Rate of Return (IRR) were calculated to assess the economic feasibility of the current operations as well as possible retrofit of STP. The Force Field Analysis (FFA) was used to address the institutional aspects of the STOP management. The results indicate that the STP process units are operational and are able to reduce contaminant levels to below the quality standards, however with some modifications on the anaerobic ponds and Imhoff tank without the need for expansion. The rest of the plant needs only to be pushed to its design capacity. Furthermore, the financial situation of the STP will recover with the addition of the new customers and from the sales of dry sludge or manure. The study revealed opportunities for institutional development from The Regional Technical Service Unit (RTSU) institutional form to an institutional form with the Financial Management Pattern of the Regional Public Service Agency (FMP-RPSA).