The quality of water from protected springs in Katwe and Kisenyi parishes, Kampala city, Uganda

Background: In the sub-urban areas of Kampala city, springs are a major source of water for domestic use. Though spring water is considered to be aesthetically acceptable for domestic use, presence of poorly designed pit latrines, poor solid waste management as well as poor and inadequate spring protection, may lead to contamination of spring water with pathogenic bacteria. Objectives: The objectives of the study were to examine the bacteriological quality of water from ten springs in Katwe and Kisenyi parishes of Kampala, and to identify and quantify risks for spring water contamination with faecal bacteria. Methods: A cross-sectional sanitary risk assessment using a standardised format was carried out in ten randomly selected springs in the parishes of Katwe and Kisenyi parishes in Kampala. A total of 80 samples of water from these springs were collected from December 2001 to March 2002. The samples were analysed for indicators of faecal contamination: total coliforms, faecal coliforms and faecal streptococci. Physico-chemical parameters were measured. Results: Aggregate qualitative sanitary risk scores ranged from medium to high. The total coliform counts in 90% of the samples exceeded the WHO guideline for drinking water. All the samples had faecal coliform counts above the WHO guideline. A strong correlation (r2= 887) was observed between the median faecal coliform counts and the sanitary risk score. Sixty percent of the samples had nitrate levels above the WHO recommended limit. There was no correlation between the levels of chlorides and nitrates and levels of indicators of faecal bacterial contamination. Conclusions: The sanitary risk assessment score is a reliable tool for predicting the likely levels of bacterial contamination of spring water. Water from the ten protected springs studied is unsuitable for drinking without treatment