Evaluating the impact of the microbial properties of dumpsites leachate on groundwater quality in Awka, Anambra State and its environs

Chike Pius Nwachukwu; Chukwuemeka Obumneme Umobi; Victory Chukwudumebi Nwaorgu; Francis Chukwudalu Okwuosa; Promise Sonyeluchukwu Offoma

Authors

Chike Pius Nwachukwu Nnamdi Azikiwe University, Nigeria
Chukwuemeka Obumneme Umobi Nnamdi Azikiwe University, Nigeria
Victory Chukwudumebi Nwaorgu Nnamdi Azikiwe University, Nigeria
Francis Chukwudalu Okwuosa Nnamdi Azikiwe University, Nigeria
Promise Sonyeluchukwu Offoma Nnamdi Azikiwe University, Nigeria

Keywords:

Dumpsite, Groundwater, Leachate, Microbial properties, Permeable soil

Abstract

Groundwater contamination from dumpsite leachate presents significant environmental and public health concerns in Awka South Local Government Area (LGA), Anambra State, Nigeria. This study investigated the microbial characteristics of leachate from informal dumpsites and their effects on groundwater quality in six communities: Amawbia, Agu-Awka, Ifite, Okpuno, Amaenyi, and Amansea. Six groundwater and six leachate samples were collected using stratified sampling based on proximity to dumpsites. Microbial analyses were performed using Nutrient Agar for total bacterial counts (TBC) and Eosin Methylene Blue agar for total coliform counts (TCC), followed by incubation at 37°C for 24–48 hours, while bacterial identification was conducted using standard biochemical tests guided by Bergey’s Manual. Pathogens detected included Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Staphylococcus aureus, and Shigella flexneri. Results showed elevated microbial loads, with TBC ranging from 89 to 285 CFU/ml and TCC from 0 to 89 CFU/ml. Leachate samples consistently exhibited higher contamination, and similar pathogens in paired samples indicate leachate infiltration into groundwater. All samples exceeded World Health Organization standards for drinking water, highlighting the need for improved waste management, leachate treatment, routine monitoring, and public awareness to protect groundwater resources and public health.

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