Journal of the Sanitary Engineering Division · 1971 · 10 citations · 0 references
EngineeringEnvironmental EngineeringEnvironmental SciencesUrban Water ManagementWaste ManagementWastewater TreatmentMunicipal Solid Waste ManagementOrganic Waste ManagementWaste CharacterizationWaste Management SystemsWaste TreatmentWastewater CharacterizationFrequency SamplingOrganic Loading RatePollution Load AssessmentSampling Frequency Selection
Short-term loading fluctuations in waste treatment system are ignored in design because of the difficulty in obtaining meaningful data. Statistical analyses of hourly COD values from a combined sewer system within the Minneapolis–St. Paul Sanitary District were performed to characterize the data. Once the periodic components were removed, the data were found to be random, stationary, ergodic and normally distributed. The minimum sampling frequency necessary to properly characterize the data was found to be from 1–1/2 hr to 2 hr.