Access to safe drinking water is still a challenge, mainly in resource-poor regions where the quality of their water source usually goes uninspected. This paper describes a low-cost, portable water-monitoring system designed to sense a few important parameters like pH, turbidity, TDS, and gas levels. It uses an Arduino UNO microcontroller with sensors interfaced to it. An innovative visual feedback mechanism using LED indicators (green, yellow, and red) simplifies the interpretation of water quality for individuals with minimal technical expertise. Quantitative testing of the system demonstrated high reliability and accuracy. For instance, pH measurements were accurate within ± 0.1 units, turbidity readings within ± 5 NTU, TDS reading within ± 2 ppm, and gas (CO \(_2\) , sulfur) sensors effectively identified variations in gas levels within a 5% margin of error. Sample testing is done on a wide variety of local water sources, including rural, urban, and industrial areas to ensure robustness. The samples were of different contamination levels, ranging from clean water sources to those with moderate to heavy pollution. This makes it a practical tool for improving public health and promoting environmental stability.