Socioeconomic Based Design Flow Factors for Small Sewerage Systems

In this study, a simulation model is developed to generate synthetic wastewater flow hydrographs resulting from a community with specific socio-economic conditions. The synthetic hydrographs are developed while retaining their commonly observed random behavior. The socioeconomic characteristics of a community are accounted for by the composition of the community and its social categories, the water use pattern of every category during the various daily activities (weekday and weekend), and the water use facilities (fixtures and appliances) available to the community. The model utilizes different water use patterns by every social group for every appliance during the different day types e.g. weekday and weekend. The use patterns account for the stochastic nature of use in terms of number of uses, duration of use and times of use in the day. Randomly generated hydrographs are generated for weekdays and weekends. The daily sewer hydrographs are transformed by hydraulic routing through the sump -pump to daily pumped flow hydrographs conveying wastewater to the treatment plant.