Planning and evaluation of sewage management in Simokerto District (Indonesia)

Simokerto District has 45 units of communal wastewater treatment plant (WWTP), but their operations still face several problems such as effluent that does not meet the quality standards, poorly maintained physical conditions of the buildings, unsuitable designs, and some residents are not yet managing their domestic wastewater. Therefore, the communal WWTPs in Simokerto District need to be evaluated and appropriate strategies for future domestic wastewater management need to be determined. The evaluation and planning in this research, refer to technical, social, and financial aspects based on quantitative and qualitative analysis results from primary and secondary data collection. Primary data collection was done through direct observation and interviews with questionnaires for all Simokerto residents. Primary data collection includes the existing conditions of domestic wastewater management, existing conditions of WWTPs, as well as the social and financial conditions of Simokerto residents. The results of the technical aspect evaluation indicate that the communal WWTPs on Sidoyoso Wetan still has the potential to increase their service until 238 people, but requires a redesign by adding 1 compartment of UAF and disinfection process by adding chlorine tablet in effluent pipe. Meanwhile, the communal WWTP on Granting still needs a leakage reparation, the construction of new dedicated domestic wastewater channel, and a redesign of the WWTP by enlarging the overall dimensions of the WWTP and disinfection process by adding chlorine tablet in effluent pipe. The planning for the development of domestic wastewater management services in Simokerto District can be done by building 245 units of new communal WWTP with 35.10 m3 capacity with ABR as a treatment unit. The strategy from the evaluation of the social aspects indicates the need to increase residents’ interest in managing domestic wastewater by planning communal WWTP, which the treated water can be reused by the residents. The strategy from the evaluation of the financial aspects indicates that the Surabaya City Government requires funds amounting to Rp. 13,478,435,077 for the construction of 245 new communal wastewater treatment plants to assist residents of Simokerto who are not yet using communal wastewater treatment plants.