The ovipositional response of Culex quinquefasciatus to water from 2 areas in a salt marsh impoundment receiving wastewater, holding pond water and distilled water was tested in a large screened outdoor enclosure. Gravid females did not significantly prefer water from the wastewater discharge point into an impoundment to water from a holding pond. They did prefer these 2 sources over both water taken 600 m into that impoundment and to distilled water. Nitrate or orthophosphate levels alone were not sufficient to determine relative ovipositional preference to these water sources.