Quality of greywater based on economic class and generation time (a case study of Ciliwung watershed, Indonesia)

University of Indonesia, Civil and Environmental Engineering Department, 16424 Depok, Indonesia

^* Corresponding author: adhiragapratama@ui.ac.id

Abstract

Community activities highly influence the generation of greywater, whereas community activities vary from time to time. The difference in economic class of households will also affect the lifestyle, sanitation facilities, and source of clean water used which will impact the quality of greywater. Hence, this study aimed to investigate whether differences in sampling time and economic class of households in developing countries, in particular Indonesia, will affect the quality of greywater generated. Based on laboratory analysis of greywater samples at 15 households at two different times, the results obtained were pH 5.77 - 9.52, DO 0.9 - 5.7 mg/l, COD 42 - 2190 mg/l, Ammonia 0.95 - 22.5 mg/l, and fecal coliform 1.7x10² – 1.7x10⁷ MPN/100ml. These results were analyzed using the t-test to determine the significance of the data on greywater generation between morning and afternoon as well as differences in lower middle and higher middle-class. From this analysis, it was discovered that from each parameter there was no significant difference between the greywater quality data shown in the morning and the evening. There was a significant difference in the parameters of DO and COD between samples taken at households with lower middle and higher middle economic classes.