GREYWATER IN INDONESIA: CHARACTERISTIC AND TREATMENT SYSTEMS

Abstract: Lacking in centralized wastewater treatment plant exist in all Indonesian cities. Drainage and river suffer from domestic wastewater contaminants. It also increases cost of water treatment plant operation if river used as water source. Using of greywater treatment system is believed as new solution. This paper will review application of greywater treatment in Indonesia. Some projects exist but most of them need supports from third party and their initial costs are high. Thus, low cost and reuse system in small community or household are important. Researches showed that constructed wetland is quite promising because the reduction of BOD concentration can reach 60-94%. However, land requirement and greywater generation could be the limitation and Anaerobic Baffled Reactor can be used as an alternative. Key words: domestic wastewater, greywater, reuse, decentralized wastewater treatment system, low cost treatment system, constructed wetland

Safely Managed On-Site Sanitation: A National Assessment of Sanitation Services and Potential Fecal Exposure in Indonesia

Sustainable Development Goal target 6.2 calls for universal access to adequate and equitable sanitation, setting a more ambitious standard for ‘safely managed sanitation services’. On-site sanitation systems (e.g., septic tanks) are widely used in low- and middle-income countries (LMICs). However, the lack of indicators for assessing fecal exposure risks presents a barrier to monitoring safely managed services. Furthermore, geographic diversity and frequency of disasters require a more nuanced approach to risk-informed decision-making. Taking Indonesia as an example, the purpose of this paper is to provide insights into current status and practices for on-site sanitation services in the contexts of LMICs. Using a dataset from a national socio-economic survey (n = 295,155) coupled with village census (n = 83,931), we assessed (1) household sanitation practices across Indonesia stratified by city-level population density and meteorological factors, (2) factors associated with septic tank emptying practice, and (3) inequalities in potential fecal exposure as measured by population density and WASH access by wealth quintile. We found a high reliance on on-site sanitation facilities (80.0%), almost half of which are assumed to be ‘uncontained’ septic tanks and one in ten facilities discharging untreated waste directly into the environment. The most densely populated areas had the highest rates of septic tank emptying, though emptying rates were just 17.0%, while in the lowest population density group, emptying was rarely reported. Multivariate regression analysis demonstrated an association between flooding and drought occurrence and septic tank emptying practice. Higher groundwater usage for drinking among poorer households suggests unsafe sanitation may disproportionally affect the poor. Our study underscores the urgent need to strengthen the monitoring of on-site sanitation in LMICs by developing contextualized standards. Furthermore, the inequalities in potential fecal exposure require greater attention and tailored support mechanisms to ensure the poorest gain access to safely managed sanitation services