Dissolved organic carbon (DOC) and coliform bacteria in underground waters in areas around Nairobi.

ABSTRACT

Most people in areas surrounding Nairobi use untreated underground waters for their domestic chores. A study was carried out during the wet season (April-June) and the dry season (September-November) of the year 1994 to find out if these untreated underground waters contain dissolved organic carbon (DOC) and coliform bracteria. Out of the 40 sites sampled during both the wet and dry seasons, 11 contained colifrorm bacteria during the wet season, while only 2 contained the microbes during the dry season. The microbes were detected only in the wells. DOC was detected in 37 sites during the wet season and in 31 sites during the dry season within a range of 2.0-30.8 mg L(-1 ). DOC which mainly consists of humic and fulvic acids was quantified by measuring their absorbance at 360nm by UV-VIS spectrophotometry. The presence of coliform bacteria was detected by use of microbiological techniques.