ONSITE HOUSEHOLD WASTEWATER TREATMENT FOR DISPOSAL BY LAWN SPRINKLING

A simple, inexpensive and reliable wastewater treatment system, requiring no mechanical aeration, has been developed that will allow surface spray irrigationof a homeowner's lawn with the household's wastewater. Septic tank effluent passes through a specifically designed sand filter for aerobic degradation and clarification. The treated wastewater from a holding reservoir is sprayed on the lawn through pop-up sprinklers by an electric pump.;Nutrient balances of both phosphate and nitrogen applied to the lawns and removed by grass clippings are compared.;This system would allow disposal of treated wastewater regardless of soil type or landscape. A homeowner in arid regions could enjoy a beautiful lawn without the use of additional city water.;The water quality of the irrigated water is shown to be environmentally safe and constitutes no health problem, having an average BOD of less than 5 mg/l and a suspended solids of less than 1 mg/l. Die-off studies of coliform organisms on the irrigated lawn are compared with a control lawn irrigated at the same hydraulic loading with potable water and with a nonirrigated lawn. The water quality of stormwater runoff from the irrigated lawn is shown to compare favorably with the controls runoff and is much better than average urban runoff.