Over 97.5 percent of Earth's water is saline, with only 0.8 percent accessible as freshwater through aquifers, rivers, and lakes. Rapid population growth has increased the demand for clean water, resulting in higher pollution levels from industrial waste and agricultural runoff. This pollution leads to eutrophication, degrading aquatic ecosystems. Therefore, it is essential to monitor water quality to mitigate such effects. We have developed a low-cost and low-power IoT system for real-time turbidity monitoring. This system uses LoRa (Long Range) technology to transmit data collected by a high-capacity microcontroller to a database for graphical visualization. We tested the prototype for low energy consumption, extended communication range, and quality of turbidity measurement. The results demonstrate the system's effectiveness in continuous, real-time monitoring. This system is ideal for widespread deployment across lakes for early warning detection and assessing water quality issues.