Sustainability indices and risk analysis of drinking water systems in Southwest Nigeria

Abstract

This study focused on designing a drinking water systems sustainability index for Integrated Water Resources Management in low-income countries. Water Supply Systems Sustainability Index (WSSI), a field assessment tool, was designed for rapid appraisal of drinking water systems in selected urban, peri-urban and rural Nigerian communities. The systems were classified into Highly Sustainable, Sustainable, Averagely Sustainable, and Unsustainable WSSI categories. Sanitary Risk Score (SRS) was assigned, classifying drinking water systems into Very High, High, Intermediate (Medium) and Low-Risk categories. WSSI results revealed that for urban systems, 90 are Highly Sustainable, 27 are Sustainable and 12 are Averagely Sustainable. For peri-urban systems, 13 are Highly Sustainable, 7 Sustainable and 1 Averagely Sustainable. Only urban hand-dug wells are in the Very High-Risk category. Public water supplies occurred only in the Low-Risk (17) and Intermediate-Risk (6) categories. Urban and rural boreholes had better quality than peri-urban boreholes. WSSI and SRS correlation result indicated strong positive correlation for urban hand-dug wells' (R2 = 0.5688, at p < 0.05) and weak positive correlation between peri-urban hand-dug wells' (R2 = 0.1847, at p < 0.05) and urban boreholes' WSSI and SRS (R2 = 0.2032, at p < 0.05). Findings showed that drinking water systems are, generally, sustainable and WSSI could be incorporated into community-level water supply assessment.

Water safety, antifungal-resistant aflatoxigenic aspergillus flavus and other pathogenic fungi in a community hand-dug wells

“…depth, land use, low construction standards, and proximity to multiple pollution sources (Brown et al, 2012;Odjegba et al, 2020). The fungal species isolated from hand-dug wells in this study are known as potentially pathogenic, allergenic, and toxigenic species that have been previously isolated from water (Novak Babič et 2017).…”

“…Fungal load in positive wells (91.3%) was rather very high compared with 100 CFU/ ml established by Swedish regulation and previously reported from groundwater as reviewed by Oliveira et al (2016). In Nigeria, hand‐dug wells are often exposed to contamination due to inappropriate well siting, shallow depth, land use, low construction standards, and proximity to multiple pollution sources (Brown et al, 2012; Odjegba et al, 2020). The fungal species isolated from hand‐dug wells in this study are known as potentially pathogenic, allergenic, and toxigenic species that have been previously isolated from water (Novak Babič et al, 2017).…”

“…This emanated from the government′s inability to meet the ever‐increasing water demand. The Nigerian population depends largely on groundwater as the primary source of water supply, due to the lack of provision of governmental potable pipe‐borne water (Aboh et al, 2015; Odjegba et al, 2020). These groundwater sources are easily susceptible to faecal contamination leading to the incidence and outbreak of waterborne diseases.…”

Failure mode effects and criticality analysis of water supply systems' risks: Path to water resources planning and policy

“…Residents of Ogun State rely mainly on hand‐dug wells, boreholes and the State owned public utility for their water supply needs (Oluwasanya et al, 2011). Increase in population and rapid expansion of towns have limited the adequate supply of potable water from the public utility (Odjegba, Oluwasanya, Idowu et al, 2020; Odjegba, Oluwasanya, Sadiq et al, 2020). Other factors include water shortage due to infrastructural break down, power failure and total absence of water supply in areas previously having water supply.…”

“…Previous studies on the assessment of water supply systems' risks in the study area (Oluwasanya et al, 2011; Odjegba, Oluwasanya, Idowu et al, 2020; Odjegba, Oluwasanya, Sadiq et al, 2020) focused on the use of sanitary risk inspection approach. Sanitary risk inspection is an easy to use visual survey method for assessing the risk factors that contribute to the contamination of water supply systems (Pond et al, 2020; Kelly et al, 2021).…”