Assessment of water quality and the use of sanitary surveys in identifying water source risk factors in Kisii County

Abstract

Safe drinking water is defined by the World Health Organization (WHO) as water that meets WHO guidelines or national standards for physical, chemical and microbial characteristics. Microbial contamination of drinking water can cause diarrheal and other waterborne diseases that cause morbidity and even mortality. Sanitary surveys which are observational checklists highlighting potential risks of contamination can be used because they are easier to implement than microbiological testing. The sources of contamination of water sources identified from sanitary surveys will help local authorities, develop corrective actions to prevent contamination and highlight key aspects of water source improvements. The study focused on the use of sanitary surveys in complementing water testing programmes where fecal coliform concentrations were measured, specific risk factors influencing microbiological water quality determined and household safe water management determined. This was achieved through a descriptive cross sectional study design and a stratified random sampling to arrive at the three administrative divisions of Kisii County (Keumbu, Mosocho and Kiogoro). A sanitary survey designed according to the WHO 1997 was used in collecting data and water samples were collected and analyzed in the laboratory using membrane filtration technique. A total of 25 springs, 20 wells and 16 rainwater tanks were sampled. Wells had the highest levels of contamination by fecal coliform (median=2.4CFU/100ml) and highest concentrations of TDS and turbidity compared to other sources. The median Risk of Contamination (ROC) score for wells was the highest at 59.5%. There were no significant relationships between fecal contamination concentrations and increasing risk of contamination score. Springs were predominantly used as the main source of water with 97% of the households using them and over half (58%) of the sampled households never treated their drinking water. The research study presented an up to date evidence based dataset testing microbiological water quality against source type and potential risk factors of water sources. Basic treatment of the water at the community or household level should be promoted and creation of awareness on the possibilities of spring water being contaminated should also be carried because of the assumption that spring water is safe and does not need to be treated.