EFFICACY AND EFFICIENCY OF LAGOON WASTEWATER TREATMENT AND THE EFFLUENT QUALITY WITH FOCUS ON BIOLOGICAL INDICATORS AT BARATON COMMUNITY, NANDI COUNTY, KENYA.

Abstract

Lagoon waste-water system is one of the wastewater treatment methods mostly used in semi-urban areas due to its low cost of establishment and high purification qualities (Steinmann. C., Weinhart. S., & Melzer. A., 2003). When a lagoon waste-water treatment system is properly constructed and used; the system is effective in eliminating any contaminants and pollutants in the waste-water. Poor sitting, construction and use of a lagoon waste-water treatment system poses a grave danger of pollution to the environment (EPA, 2011). The independent variable is the standard total coliform count the dependent variable is the observed total coliform count in MPN per ml. An observational descriptive cross-sectional study design was used to conduct this research. Data was collected using an observational checklist. Bacterial waste-water analysis of the waste-water was carried out in a microbiology lab and the results recorded in a wastewater sampling form. Following the descriptive analysis of the data it was observed that the total coliform count remain stagnant at 11.547MPN/ml from inlet until the last stage of treatment in this system which is the tertiary pond where there is a drastic 25% drop in total coliform count to 4.082MPN/ml. it is expected that the ponds maintain a maximum MPN/ml total coliform count of 10MPN/ml throughout the ponds during treatment and the total coliform count of the final effluent should be at a maximum of 4MPN/ml. There is a significant difference between the observed total coliform count and the expected total coliform count at a p value of 0.046 which is significant at p=0.05. In conclusion, there is increased coliform count within the ponds as observed compared to the expected coliform count at each pond hence non efficient and effective operation of the baraton lagoon waste-water treatment plant. It is recommended that the structural standards like proper construction of the ponds as well as the operational standards like controlled retention time achieved through improved standard structures of the research facility to be effected so as to optimize efficiency and efficacy of the system.