Waste water oxidation lagoon studies were conducted at Oregon State University to establish criteria for their use in the maritime climates of the Pacific Northwest. An experimental facility was constructed consisting of two cells, each one acre in surface area and three feet deep on which studies were conducted. Emphasis was placed on determination of basic factors influencing lagoon use under various conditions. These include surface reaeration mechanics, sludge accumulation and respiration, bacteriological quality, and disinfection requirements, together with other problems as defined in this report. (Author)