Methodology for assessing the state of environmental safety of drinking water supply in rural residential areas

Ensuring the environmental safety of rural drinking water supplies is a critical issue in modern ecology and water resource management. Ecosystem changes, growing human impact, and inadequate rural infrastructure degrade drinking water quality. Water resources in these regions are often polluted by improper land use, untreated sewage discharge, and excessive agrochemical use. Drinking water quality directly affects public health, making the evaluation of water supply systems essential. The problem is compounded by inadequate monitoring, assessment, and management of water resources in rural areas. This study addresses several important scientific tasks, including developing methods and models for monitoring water’s ecological status, identifying human health risks, and formulating integrated approaches to water quality management. Practical measures include improving water supply infrastructure, drafting recommendations for reducing water source pollution, and enhancing public awareness and participation in water resource conservation. The study aims to develop and substantiate methodological foundations for assessing the ecological safety of rural drinking water supply systems. This approach will facilitate identifying and preventing environmental risks while ensuring acceptable water quality for the population. The key methodological approach for assessing the ecological safety of drinking water supply systems in rural settlements is system analysis, which conceptualises rural water supply as a system with specific input and output parameters. Based on an empirical analysis of rural drinking water supply, a “black box” model of rural water systems was developed. This model includes input factors influencing groundwater quality and criteria for assessing drinking water quality. Influential factors (GQ) were categorized into subsets: agriculture (A), urbanization (U), industrial activity (I), environmental conditions (E), and public ecological awareness (EC). Each subset is further broken down into specific parameters, such as fertilizer use, waste disposal, and hydrological phenomena. The study also defines drinking water quality (QW) using organoleptic, microbiological, and toxicological indicators. Evaluation criteria (ADWQ) include water quality classes, total quality indices, comprehensive pollution coefficients, and Hamming distance metrics for rapid and objective assessments. Research conducted in rural areas of the Zhytomyr region revealed critical nitrate pollution in 59% of water samples, attributed to intensive agricultural practices. A mathematical model for assessing water quality was developed and validated, showing a strong correlation (r = 0.87) between real and predicted data. The study also found a relationship between nitrate content and health risks, highlighting high or critical risk zones, especially for children and infants. The study confirms the utility of systemic, multi-criteria approaches in assessing drinking water quality, particularly in rural areas. The developed methodology facilitates effective decision-making to mitigate health risks and improve water quality, ensuring better access to safe drinking water in rural communities. Keywords: rural water supply, drinking water, system analysis, drinking water quality, nitrates, total iron, public health.