The determination of DO and BOD levels were carried out on samples of water collected from three selected streams in Anambra state using Winkler’s method. The surface water bodies are Ezigbekwu stream in Achalla, Awka North Local Government Area, Ogobu stream in Aguluezechukwu, Aguata Local Government Area, and Ogbanta stream in Ajalli, Orumba North Local Government Area. Ezigbekwu stream gave a range of DO values from 24.5 mg /l to 37.1 mg/ l. Also, the BOD for Ezigbekwu ranged from 5.8 mg/l to 29.6 mg/l. Ogobu has DO values that range from 8.5 mg/l to 37.1 mg/l and BOD that ranges from 5.0 mg/l to 15.0 mg/l. Ogbanta stream which has a stretch of more than 2km had DO values that vary between 18.8 mg/l to 33.5 mg/l. These values were then compared with the highest desirable and maximum permissible levels set by the World Health Organization (WHO) and National Environmental Standards and Regulations Enforcement Agency (NESREA) for wastes to be discharged into natural water bodies. Most of the BOD values were below the maximum permissible limit of 40 mg/l and 30 mg/l respectively for both WHO and NESREA though they are above the standard level for potable water as stipulated by WHO. The DO values are mostly above the level critical for normal aquatic life (7.5 mg/l) indicating a nearby pollution source. The oxygen sag curves of the three streams were presented and they showed minor some differences . They were directly comparable to those of standard oxygen sag curve downstream. Thus characteristic decline and restoration of water quality of a stream can be expressed in terms of the DO and BOD levels. As these streams are water supplies for several communities along their courses in all the localities where they drain, the DO and BOD values will be useful in the design of treatment facilities as well as restoration facilities for these streams in the respective communities for the purpose of public water supply. Keywords: Self Purification, Dissolved Oxygen, Biochemical Oxygen Demand, Stream

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