Land Treatment for Primary Sewage Effluent: Water and Energy Conservation

Abstract

Land treatment of secondary municipal wastewater is an economical and aesthetic method of upgrading water quality, if hydrologic and geologic conditions are favorable. Costly conventional secondary treatment, which requires large quantities of electrical energy, can be bypassed by applying the primary effluent directly to the land. Soil- denitrifying bacteria use the organic carbon in the primary effluent as an energy source for biodenitrification and nitrogen removal. Laboratory and field studies indicated the quality of renovated wastewater meets standards for unrestricted irrigation and recreational uses. Considerable savings, both in capital and energy costs, can be realized by land treatment of primary effluent.